Add output size as a uniform to compute shaders, as an integer; not just the inverse...
[movit] / effect_chain.cpp
1 #include <epoxy/gl.h>
2 #include <assert.h>
3 #include <math.h>
4 #include <stddef.h>
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <algorithm>
9 #include <set>
10 #include <stack>
11 #include <utility>
12 #include <vector>
13 #include <Eigen/Core>
14
15 #include "alpha_division_effect.h"
16 #include "alpha_multiplication_effect.h"
17 #include "colorspace_conversion_effect.h"
18 #include "dither_effect.h"
19 #include "effect.h"
20 #include "effect_chain.h"
21 #include "effect_util.h"
22 #include "gamma_compression_effect.h"
23 #include "gamma_expansion_effect.h"
24 #include "init.h"
25 #include "input.h"
26 #include "resource_pool.h"
27 #include "util.h"
28 #include "ycbcr_conversion_effect.h"
29
30 using namespace Eigen;
31 using namespace std;
32
33 namespace movit {
34
35 namespace {
36
37 // An effect whose only purpose is to sit in a phase on its own and take the
38 // texture output from a compute shader and display it to the normal backbuffer
39 // (or any FBO). That phase can be skipped when rendering using render_to_textures().
40 class ComputeShaderOutputDisplayEffect : public Effect {
41 public:
42         ComputeShaderOutputDisplayEffect() {}
43         string effect_type_id() const override { return "ComputeShaderOutputDisplayEffect"; }
44         string output_fragment_shader() override { return read_file("identity.frag"); }
45         bool needs_texture_bounce() const override { return true; }
46 };
47
48 }  // namespace
49
50 EffectChain::EffectChain(float aspect_nom, float aspect_denom, ResourcePool *resource_pool)
51         : aspect_nom(aspect_nom),
52           aspect_denom(aspect_denom),
53           output_color_rgba(false),
54           num_output_color_ycbcr(0),
55           dither_effect(nullptr),
56           ycbcr_conversion_effect_node(nullptr),
57           intermediate_format(GL_RGBA16F),
58           intermediate_transformation(NO_FRAMEBUFFER_TRANSFORMATION),
59           num_dither_bits(0),
60           output_origin(OUTPUT_ORIGIN_BOTTOM_LEFT),
61           finalized(false),
62           resource_pool(resource_pool),
63           do_phase_timing(false) {
64         if (resource_pool == nullptr) {
65                 this->resource_pool = new ResourcePool();
66                 owns_resource_pool = true;
67         } else {
68                 owns_resource_pool = false;
69         }
70
71         // Generate a VBO with some data in (shared position and texture coordinate data).
72         float vertices[] = {
73                 0.0f, 2.0f,
74                 0.0f, 0.0f,
75                 2.0f, 0.0f
76         };
77         vbo = generate_vbo(2, GL_FLOAT, sizeof(vertices), vertices);
78 }
79
80 EffectChain::~EffectChain()
81 {
82         for (unsigned i = 0; i < nodes.size(); ++i) {
83                 delete nodes[i]->effect;
84                 delete nodes[i];
85         }
86         for (unsigned i = 0; i < phases.size(); ++i) {
87                 resource_pool->release_glsl_program(phases[i]->glsl_program_num);
88                 delete phases[i];
89         }
90         if (owns_resource_pool) {
91                 delete resource_pool;
92         }
93         glDeleteBuffers(1, &vbo);
94         check_error();
95 }
96
97 Input *EffectChain::add_input(Input *input)
98 {
99         assert(!finalized);
100         inputs.push_back(input);
101         add_node(input);
102         return input;
103 }
104
105 void EffectChain::add_output(const ImageFormat &format, OutputAlphaFormat alpha_format)
106 {
107         assert(!finalized);
108         assert(!output_color_rgba);
109         output_format = format;
110         output_alpha_format = alpha_format;
111         output_color_rgba = true;
112 }
113
114 void EffectChain::add_ycbcr_output(const ImageFormat &format, OutputAlphaFormat alpha_format,
115                                    const YCbCrFormat &ycbcr_format, YCbCrOutputSplitting output_splitting,
116                                    GLenum output_type)
117 {
118         assert(!finalized);
119         assert(num_output_color_ycbcr < 2);
120         output_format = format;
121         output_alpha_format = alpha_format;
122
123         if (num_output_color_ycbcr == 1) {
124                 // Check that the format is the same.
125                 assert(output_ycbcr_format.luma_coefficients == ycbcr_format.luma_coefficients);
126                 assert(output_ycbcr_format.full_range == ycbcr_format.full_range);
127                 assert(output_ycbcr_format.num_levels == ycbcr_format.num_levels);
128                 assert(output_ycbcr_format.chroma_subsampling_x == 1);
129                 assert(output_ycbcr_format.chroma_subsampling_y == 1);
130                 assert(output_ycbcr_type == output_type);
131         } else {
132                 output_ycbcr_format = ycbcr_format;
133                 output_ycbcr_type = output_type;
134         }
135         output_ycbcr_splitting[num_output_color_ycbcr++] = output_splitting;
136
137         assert(ycbcr_format.chroma_subsampling_x == 1);
138         assert(ycbcr_format.chroma_subsampling_y == 1);
139 }
140
141 void EffectChain::change_ycbcr_output_format(const YCbCrFormat &ycbcr_format)
142 {
143         assert(num_output_color_ycbcr > 0);
144         assert(output_ycbcr_format.chroma_subsampling_x == 1);
145         assert(output_ycbcr_format.chroma_subsampling_y == 1);
146
147         output_ycbcr_format = ycbcr_format;
148         if (finalized) {
149                 YCbCrConversionEffect *effect = (YCbCrConversionEffect *)(ycbcr_conversion_effect_node->effect);
150                 effect->change_output_format(ycbcr_format);
151         }
152 }
153
154 Node *EffectChain::add_node(Effect *effect)
155 {
156         for (unsigned i = 0; i < nodes.size(); ++i) {
157                 assert(nodes[i]->effect != effect);
158         }
159
160         Node *node = new Node;
161         node->effect = effect;
162         node->disabled = false;
163         node->output_color_space = COLORSPACE_INVALID;
164         node->output_gamma_curve = GAMMA_INVALID;
165         node->output_alpha_type = ALPHA_INVALID;
166         node->needs_mipmaps = false;
167         node->one_to_one_sampling = false;
168         node->strong_one_to_one_sampling = false;
169
170         nodes.push_back(node);
171         node_map[effect] = node;
172         effect->inform_added(this);
173         return node;
174 }
175
176 void EffectChain::connect_nodes(Node *sender, Node *receiver)
177 {
178         sender->outgoing_links.push_back(receiver);
179         receiver->incoming_links.push_back(sender);
180 }
181
182 void EffectChain::replace_receiver(Node *old_receiver, Node *new_receiver)
183 {
184         new_receiver->incoming_links = old_receiver->incoming_links;
185         old_receiver->incoming_links.clear();
186         
187         for (unsigned i = 0; i < new_receiver->incoming_links.size(); ++i) {
188                 Node *sender = new_receiver->incoming_links[i];
189                 for (unsigned j = 0; j < sender->outgoing_links.size(); ++j) {
190                         if (sender->outgoing_links[j] == old_receiver) {
191                                 sender->outgoing_links[j] = new_receiver;
192                         }
193                 }
194         }       
195 }
196
197 void EffectChain::replace_sender(Node *old_sender, Node *new_sender)
198 {
199         new_sender->outgoing_links = old_sender->outgoing_links;
200         old_sender->outgoing_links.clear();
201         
202         for (unsigned i = 0; i < new_sender->outgoing_links.size(); ++i) {
203                 Node *receiver = new_sender->outgoing_links[i];
204                 for (unsigned j = 0; j < receiver->incoming_links.size(); ++j) {
205                         if (receiver->incoming_links[j] == old_sender) {
206                                 receiver->incoming_links[j] = new_sender;
207                         }
208                 }
209         }       
210 }
211
212 void EffectChain::insert_node_between(Node *sender, Node *middle, Node *receiver)
213 {
214         for (unsigned i = 0; i < sender->outgoing_links.size(); ++i) {
215                 if (sender->outgoing_links[i] == receiver) {
216                         sender->outgoing_links[i] = middle;
217                         middle->incoming_links.push_back(sender);
218                 }
219         }
220         for (unsigned i = 0; i < receiver->incoming_links.size(); ++i) {
221                 if (receiver->incoming_links[i] == sender) {
222                         receiver->incoming_links[i] = middle;
223                         middle->outgoing_links.push_back(receiver);
224                 }
225         }
226
227         assert(middle->incoming_links.size() == middle->effect->num_inputs());
228 }
229
230 GLenum EffectChain::get_input_sampler(Node *node, unsigned input_num) const
231 {
232         assert(node->effect->needs_texture_bounce());
233         assert(input_num < node->incoming_links.size());
234         assert(node->incoming_links[input_num]->bound_sampler_num >= 0);
235         assert(node->incoming_links[input_num]->bound_sampler_num < 8);
236         return GL_TEXTURE0 + node->incoming_links[input_num]->bound_sampler_num;
237 }
238
239 GLenum EffectChain::has_input_sampler(Node *node, unsigned input_num) const
240 {
241         assert(input_num < node->incoming_links.size());
242         return node->incoming_links[input_num]->bound_sampler_num >= 0 &&
243                 node->incoming_links[input_num]->bound_sampler_num < 8;
244 }
245
246 void EffectChain::find_all_nonlinear_inputs(Node *node, vector<Node *> *nonlinear_inputs)
247 {
248         if (node->output_gamma_curve == GAMMA_LINEAR &&
249             node->effect->effect_type_id() != "GammaCompressionEffect") {
250                 return;
251         }
252         if (node->effect->num_inputs() == 0) {
253                 nonlinear_inputs->push_back(node);
254         } else {
255                 assert(node->effect->num_inputs() == node->incoming_links.size());
256                 for (unsigned i = 0; i < node->incoming_links.size(); ++i) {
257                         find_all_nonlinear_inputs(node->incoming_links[i], nonlinear_inputs);
258                 }
259         }
260 }
261
262 Effect *EffectChain::add_effect(Effect *effect, const vector<Effect *> &inputs)
263 {
264         assert(!finalized);
265         assert(inputs.size() == effect->num_inputs());
266         Node *node = add_node(effect);
267         for (unsigned i = 0; i < inputs.size(); ++i) {
268                 assert(node_map.count(inputs[i]) != 0);
269                 connect_nodes(node_map[inputs[i]], node);
270         }
271         return effect;
272 }
273
274 // ESSL doesn't support token pasting. Replace PREFIX(x) with <effect_id>_x.
275 string replace_prefix(const string &text, const string &prefix)
276 {
277         string output;
278         size_t start = 0;
279
280         while (start < text.size()) {
281                 size_t pos = text.find("PREFIX(", start);
282                 if (pos == string::npos) {
283                         output.append(text.substr(start, string::npos));
284                         break;
285                 }
286
287                 output.append(text.substr(start, pos - start));
288                 output.append(prefix);
289                 output.append("_");
290
291                 pos += strlen("PREFIX(");
292         
293                 // Output stuff until we find the matching ), which we then eat.
294                 int depth = 1;
295                 size_t end_arg_pos = pos;
296                 while (end_arg_pos < text.size()) {
297                         if (text[end_arg_pos] == '(') {
298                                 ++depth;
299                         } else if (text[end_arg_pos] == ')') {
300                                 --depth;
301                                 if (depth == 0) {
302                                         break;
303                                 }
304                         }
305                         ++end_arg_pos;
306                 }
307                 output.append(text.substr(pos, end_arg_pos - pos));
308                 ++end_arg_pos;
309                 assert(depth == 0);
310                 start = end_arg_pos;
311         }
312         return output;
313 }
314
315 namespace {
316
317 template<class T>
318 void extract_uniform_declarations(const vector<Uniform<T>> &effect_uniforms,
319                                   const string &type_specifier,
320                                   const string &effect_id,
321                                   vector<Uniform<T>> *phase_uniforms,
322                                   string *glsl_string)
323 {
324         for (unsigned i = 0; i < effect_uniforms.size(); ++i) {
325                 phase_uniforms->push_back(effect_uniforms[i]);
326                 phase_uniforms->back().prefix = effect_id;
327
328                 *glsl_string += string("uniform ") + type_specifier + " " + effect_id
329                         + "_" + effect_uniforms[i].name + ";\n";
330         }
331 }
332
333 template<class T>
334 void extract_uniform_array_declarations(const vector<Uniform<T>> &effect_uniforms,
335                                         const string &type_specifier,
336                                         const string &effect_id,
337                                         vector<Uniform<T>> *phase_uniforms,
338                                         string *glsl_string)
339 {
340         for (unsigned i = 0; i < effect_uniforms.size(); ++i) {
341                 phase_uniforms->push_back(effect_uniforms[i]);
342                 phase_uniforms->back().prefix = effect_id;
343
344                 char buf[256];
345                 snprintf(buf, sizeof(buf), "uniform %s %s_%s[%d];\n",
346                         type_specifier.c_str(), effect_id.c_str(),
347                         effect_uniforms[i].name.c_str(),
348                         int(effect_uniforms[i].num_values));
349                 *glsl_string += buf;
350         }
351 }
352
353 template<class T>
354 void collect_uniform_locations(GLuint glsl_program_num, vector<Uniform<T>> *phase_uniforms)
355 {
356         for (unsigned i = 0; i < phase_uniforms->size(); ++i) {
357                 Uniform<T> &uniform = (*phase_uniforms)[i];
358                 uniform.location = get_uniform_location(glsl_program_num, uniform.prefix, uniform.name);
359         }
360 }
361
362 }  // namespace
363
364 void EffectChain::compile_glsl_program(Phase *phase)
365 {
366         string frag_shader_header;
367         if (phase->is_compute_shader) {
368                 frag_shader_header = read_file("header.comp");
369         } else {
370                 frag_shader_header = read_version_dependent_file("header", "frag");
371         }
372         string frag_shader = "";
373
374         // Create functions and uniforms for all the texture inputs that we need.
375         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
376                 Node *input = phase->inputs[i]->output_node;
377                 char effect_id[256];
378                 sprintf(effect_id, "in%u", i);
379                 phase->effect_ids.insert(make_pair(input, effect_id));
380         
381                 frag_shader += string("uniform sampler2D tex_") + effect_id + ";\n";
382                 frag_shader += string("vec4 ") + effect_id + "(vec2 tc) {\n";
383                 frag_shader += "\tvec4 tmp = tex2D(tex_" + string(effect_id) + ", tc);\n";
384
385                 if (intermediate_transformation == SQUARE_ROOT_FRAMEBUFFER_TRANSFORMATION &&
386                     phase->inputs[i]->output_node->output_gamma_curve == GAMMA_LINEAR) {
387                         frag_shader += "\ttmp.rgb *= tmp.rgb;\n";
388                 }
389
390                 frag_shader += "\treturn tmp;\n";
391                 frag_shader += "}\n";
392                 frag_shader += "\n";
393
394                 Uniform<int> uniform;
395                 uniform.name = effect_id;
396                 uniform.value = &phase->input_samplers[i];
397                 uniform.prefix = "tex";
398                 uniform.num_values = 1;
399                 uniform.location = -1;
400                 phase->uniforms_sampler2d.push_back(uniform);
401         }
402
403         // Give each effect in the phase its own ID.
404         for (unsigned i = 0; i < phase->effects.size(); ++i) {
405                 Node *node = phase->effects[i];
406                 char effect_id[256];
407                 sprintf(effect_id, "eff%u", i);
408                 phase->effect_ids.insert(make_pair(node, effect_id));
409         }
410
411         for (unsigned i = 0; i < phase->effects.size(); ++i) {
412                 Node *node = phase->effects[i];
413                 const string effect_id = phase->effect_ids[node];
414                 if (node->incoming_links.size() == 1) {
415                         Node *input = node->incoming_links[0];
416                         if (i != 0 && input->effect->is_compute_shader()) {
417                                 // First effect after the compute shader reads the value
418                                 // that cs_output() wrote to a global variable.
419                                 frag_shader += string("#define INPUT(tc) CS_OUTPUT_VAL\n");
420                         } else {
421                                 frag_shader += string("#define INPUT ") + phase->effect_ids[input] + "\n";
422                         }
423                 } else {
424                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
425                                 assert(!node->incoming_links[j]->effect->is_compute_shader());
426                                 char buf[256];
427                                 sprintf(buf, "#define INPUT%d %s\n", j + 1, phase->effect_ids[node->incoming_links[j]].c_str());
428                                 frag_shader += buf;
429                         }
430                 }
431         
432                 frag_shader += "\n";
433                 frag_shader += string("#define FUNCNAME ") + effect_id + "\n";
434                 if (node->effect->is_compute_shader()) {
435                         frag_shader += string("#define NORMALIZE_TEXTURE_COORDS(tc) ((tc) * ") + effect_id + "_inv_output_size + " + effect_id + "_output_texcoord_adjust)\n";
436                 }
437                 frag_shader += replace_prefix(node->effect->output_fragment_shader(), effect_id);
438                 frag_shader += "#undef FUNCNAME\n";
439                 if (node->incoming_links.size() == 1) {
440                         frag_shader += "#undef INPUT\n";
441                 } else {
442                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
443                                 char buf[256];
444                                 sprintf(buf, "#undef INPUT%d\n", j + 1);
445                                 frag_shader += buf;
446                         }
447                 }
448                 frag_shader += "\n";
449         }
450         if (phase->is_compute_shader) {
451                 frag_shader += string("#define INPUT ") + phase->effect_ids[phase->compute_shader_node] + "\n";
452                 if (phase->compute_shader_node == phase->effects.back()) {
453                         // No postprocessing.
454                         frag_shader += "#define CS_POSTPROC(tc) CS_OUTPUT_VAL\n";
455                 } else {
456                         frag_shader += string("#define CS_POSTPROC ") + phase->effect_ids[phase->effects.back()] + "\n";
457                 }
458         } else {
459                 frag_shader += string("#define INPUT ") + phase->effect_ids[phase->effects.back()] + "\n";
460         }
461
462         // If we're the last phase, add the right #defines for Y'CbCr multi-output as needed.
463         vector<string> frag_shader_outputs;  // In order.
464         if (phase->output_node->outgoing_links.empty() && num_output_color_ycbcr > 0) {
465                 switch (output_ycbcr_splitting[0]) {
466                 case YCBCR_OUTPUT_INTERLEAVED:
467                         // No #defines set.
468                         frag_shader_outputs.push_back("FragColor");
469                         break;
470                 case YCBCR_OUTPUT_SPLIT_Y_AND_CBCR:
471                         frag_shader += "#define YCBCR_OUTPUT_SPLIT_Y_AND_CBCR 1\n";
472                         frag_shader_outputs.push_back("Y");
473                         frag_shader_outputs.push_back("Chroma");
474                         break;
475                 case YCBCR_OUTPUT_PLANAR:
476                         frag_shader += "#define YCBCR_OUTPUT_PLANAR 1\n";
477                         frag_shader_outputs.push_back("Y");
478                         frag_shader_outputs.push_back("Cb");
479                         frag_shader_outputs.push_back("Cr");
480                         break;
481                 default:
482                         assert(false);
483                 }
484
485                 if (num_output_color_ycbcr > 1) {
486                         switch (output_ycbcr_splitting[1]) {
487                         case YCBCR_OUTPUT_INTERLEAVED:
488                                 frag_shader += "#define SECOND_YCBCR_OUTPUT_INTERLEAVED 1\n";
489                                 frag_shader_outputs.push_back("YCbCr2");
490                                 break;
491                         case YCBCR_OUTPUT_SPLIT_Y_AND_CBCR:
492                                 frag_shader += "#define SECOND_YCBCR_OUTPUT_SPLIT_Y_AND_CBCR 1\n";
493                                 frag_shader_outputs.push_back("Y2");
494                                 frag_shader_outputs.push_back("Chroma2");
495                                 break;
496                         case YCBCR_OUTPUT_PLANAR:
497                                 frag_shader += "#define SECOND_YCBCR_OUTPUT_PLANAR 1\n";
498                                 frag_shader_outputs.push_back("Y2");
499                                 frag_shader_outputs.push_back("Cb2");
500                                 frag_shader_outputs.push_back("Cr2");
501                                 break;
502                         default:
503                                 assert(false);
504                         }
505                 }
506
507                 if (output_color_rgba) {
508                         // Note: Needs to come in the header, because not only the
509                         // output needs to see it (YCbCrConversionEffect and DitherEffect
510                         // do, too).
511                         frag_shader_header += "#define YCBCR_ALSO_OUTPUT_RGBA 1\n";
512                         frag_shader_outputs.push_back("RGBA");
513                 }
514         }
515
516         // If we're bouncing to a temporary texture, signal transformation if desired.
517         if (!phase->output_node->outgoing_links.empty()) {
518                 if (intermediate_transformation == SQUARE_ROOT_FRAMEBUFFER_TRANSFORMATION &&
519                     phase->output_node->output_gamma_curve == GAMMA_LINEAR) {
520                         frag_shader += "#define SQUARE_ROOT_TRANSFORMATION 1\n";
521                 }
522         }
523
524         if (phase->is_compute_shader) {
525                 frag_shader.append(read_file("footer.comp"));
526                 phase->compute_shader_node->effect->register_uniform_ivec2("output_size", phase->uniform_output_size);
527                 phase->compute_shader_node->effect->register_uniform_vec2("inv_output_size", (float *)&phase->inv_output_size);
528                 phase->compute_shader_node->effect->register_uniform_vec2("output_texcoord_adjust", (float *)&phase->output_texcoord_adjust);
529         } else {
530                 frag_shader.append(read_file("footer.frag"));
531         }
532
533         // Collect uniforms from all effects and output them. Note that this needs
534         // to happen after output_fragment_shader(), even though the uniforms come
535         // before in the output source, since output_fragment_shader() is allowed
536         // to register new uniforms (e.g. arrays that are of unknown length until
537         // finalization time).
538         // TODO: Make a uniform block for platforms that support it.
539         string frag_shader_uniforms = "";
540         for (unsigned i = 0; i < phase->effects.size(); ++i) {
541                 Node *node = phase->effects[i];
542                 Effect *effect = node->effect;
543                 const string effect_id = phase->effect_ids[node];
544                 extract_uniform_declarations(effect->uniforms_image2d, "image2D", effect_id, &phase->uniforms_image2d, &frag_shader_uniforms);
545                 extract_uniform_declarations(effect->uniforms_sampler2d, "sampler2D", effect_id, &phase->uniforms_sampler2d, &frag_shader_uniforms);
546                 extract_uniform_declarations(effect->uniforms_bool, "bool", effect_id, &phase->uniforms_bool, &frag_shader_uniforms);
547                 extract_uniform_declarations(effect->uniforms_int, "int", effect_id, &phase->uniforms_int, &frag_shader_uniforms);
548                 extract_uniform_declarations(effect->uniforms_ivec2, "ivec2", effect_id, &phase->uniforms_ivec2, &frag_shader_uniforms);
549                 extract_uniform_declarations(effect->uniforms_float, "float", effect_id, &phase->uniforms_float, &frag_shader_uniforms);
550                 extract_uniform_declarations(effect->uniforms_vec2, "vec2", effect_id, &phase->uniforms_vec2, &frag_shader_uniforms);
551                 extract_uniform_declarations(effect->uniforms_vec3, "vec3", effect_id, &phase->uniforms_vec3, &frag_shader_uniforms);
552                 extract_uniform_declarations(effect->uniforms_vec4, "vec4", effect_id, &phase->uniforms_vec4, &frag_shader_uniforms);
553                 extract_uniform_array_declarations(effect->uniforms_float_array, "float", effect_id, &phase->uniforms_float, &frag_shader_uniforms);
554                 extract_uniform_array_declarations(effect->uniforms_vec2_array, "vec2", effect_id, &phase->uniforms_vec2, &frag_shader_uniforms);
555                 extract_uniform_array_declarations(effect->uniforms_vec3_array, "vec3", effect_id, &phase->uniforms_vec3, &frag_shader_uniforms);
556                 extract_uniform_array_declarations(effect->uniforms_vec4_array, "vec4", effect_id, &phase->uniforms_vec4, &frag_shader_uniforms);
557                 extract_uniform_declarations(effect->uniforms_mat3, "mat3", effect_id, &phase->uniforms_mat3, &frag_shader_uniforms);
558         }
559
560         string vert_shader = read_version_dependent_file("vs", "vert");
561
562         // If we're the last phase and need to flip the picture to compensate for
563         // the origin, tell the vertex or compute shader so.
564         bool is_last_phase;
565         if (has_dummy_effect) {
566                 is_last_phase = (phase->output_node->outgoing_links.size() == 1 &&
567                         phase->output_node->outgoing_links[0]->effect->effect_type_id() == "ComputeShaderOutputDisplayEffect");
568         } else {
569                 is_last_phase = phase->output_node->outgoing_links.empty();
570         }
571         if (is_last_phase && output_origin == OUTPUT_ORIGIN_TOP_LEFT) {
572                 if (phase->is_compute_shader) {
573                         frag_shader_header += "#define FLIP_ORIGIN 1\n";
574                 } else {
575                         const string needle = "#define FLIP_ORIGIN 0";
576                         size_t pos = vert_shader.find(needle);
577                         assert(pos != string::npos);
578
579                         vert_shader[pos + needle.size() - 1] = '1';
580                 }
581         }
582
583         frag_shader = frag_shader_header + frag_shader_uniforms + frag_shader;
584
585         if (phase->is_compute_shader) {
586                 phase->glsl_program_num = resource_pool->compile_glsl_compute_program(frag_shader);
587
588                 Uniform<int> uniform;
589                 uniform.name = "outbuf";
590                 uniform.value = &phase->outbuf_image_unit;
591                 uniform.prefix = "tex";
592                 uniform.num_values = 1;
593                 uniform.location = -1;
594                 phase->uniforms_image2d.push_back(uniform);
595         } else {
596                 phase->glsl_program_num = resource_pool->compile_glsl_program(vert_shader, frag_shader, frag_shader_outputs);
597         }
598         GLint position_attribute_index = glGetAttribLocation(phase->glsl_program_num, "position");
599         GLint texcoord_attribute_index = glGetAttribLocation(phase->glsl_program_num, "texcoord");
600         if (position_attribute_index != -1) {
601                 phase->attribute_indexes.insert(position_attribute_index);
602         }
603         if (texcoord_attribute_index != -1) {
604                 phase->attribute_indexes.insert(texcoord_attribute_index);
605         }
606
607         // Collect the resulting location numbers for each uniform.
608         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_image2d);
609         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_sampler2d);
610         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_bool);
611         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_int);
612         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_ivec2);
613         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_float);
614         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_vec2);
615         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_vec3);
616         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_vec4);
617         collect_uniform_locations(phase->glsl_program_num, &phase->uniforms_mat3);
618 }
619
620 // Construct GLSL programs, starting at the given effect and following
621 // the chain from there. We end a program every time we come to an effect
622 // marked as "needs texture bounce", one that is used by multiple other
623 // effects, every time we need to bounce due to output size change
624 // (not all size changes require ending), and of course at the end.
625 //
626 // We follow a quite simple depth-first search from the output, although
627 // without recursing explicitly within each phase.
628 Phase *EffectChain::construct_phase(Node *output, map<Node *, Phase *> *completed_effects)
629 {
630         if (completed_effects->count(output)) {
631                 return (*completed_effects)[output];
632         }
633
634         Phase *phase = new Phase;
635         phase->output_node = output;
636         phase->is_compute_shader = false;
637         phase->compute_shader_node = nullptr;
638
639         // If the output effect has one-to-one sampling, we try to trace this
640         // status down through the dependency chain. This is important in case
641         // we hit an effect that changes output size (and not sets a virtual
642         // output size); if we have one-to-one sampling, we don't have to break
643         // the phase.
644         output->one_to_one_sampling = output->effect->one_to_one_sampling();
645         output->strong_one_to_one_sampling = output->effect->strong_one_to_one_sampling();
646
647         // Effects that we have yet to calculate, but that we know should
648         // be in the current phase.
649         stack<Node *> effects_todo_this_phase;
650         effects_todo_this_phase.push(output);
651
652         while (!effects_todo_this_phase.empty()) {
653                 Node *node = effects_todo_this_phase.top();
654                 effects_todo_this_phase.pop();
655
656                 assert(node->effect->one_to_one_sampling() >= node->effect->strong_one_to_one_sampling());
657
658                 if (node->effect->needs_mipmaps()) {
659                         node->needs_mipmaps = true;
660                 }
661
662                 // This should currently only happen for effects that are inputs
663                 // (either true inputs or phase outputs). We special-case inputs,
664                 // and then deduplicate phase outputs below.
665                 if (node->effect->num_inputs() == 0) {
666                         if (find(phase->effects.begin(), phase->effects.end(), node) != phase->effects.end()) {
667                                 continue;
668                         }
669                 } else {
670                         assert(completed_effects->count(node) == 0);
671                 }
672
673                 phase->effects.push_back(node);
674                 if (node->effect->is_compute_shader()) {
675                         phase->is_compute_shader = true;
676                         phase->compute_shader_node = node;
677                 }
678
679                 // Find all the dependencies of this effect, and add them to the stack.
680                 vector<Node *> deps = node->incoming_links;
681                 assert(node->effect->num_inputs() == deps.size());
682                 for (unsigned i = 0; i < deps.size(); ++i) {
683                         bool start_new_phase = false;
684
685                         if (node->effect->needs_texture_bounce() &&
686                             !deps[i]->effect->is_single_texture() &&
687                             !deps[i]->effect->override_disable_bounce()) {
688                                 start_new_phase = true;
689                         }
690
691                         // Propagate information about needing mipmaps down the chain,
692                         // breaking the phase if we notice an incompatibility.
693                         //
694                         // Note that we cannot do this propagation as a normal pass,
695                         // because it needs information about where the phases end
696                         // (we should not propagate the flag across phases).
697                         if (node->needs_mipmaps) {
698                                 if (deps[i]->effect->num_inputs() == 0) {
699                                         Input *input = static_cast<Input *>(deps[i]->effect);
700                                         start_new_phase |= !input->can_supply_mipmaps();
701                                 } else {
702                                         deps[i]->needs_mipmaps = true;
703                                 }
704                         }
705
706                         if (deps[i]->outgoing_links.size() > 1) {
707                                 if (!deps[i]->effect->is_single_texture()) {
708                                         // More than one effect uses this as the input,
709                                         // and it is not a texture itself.
710                                         // The easiest thing to do (and probably also the safest
711                                         // performance-wise in most cases) is to bounce it to a texture
712                                         // and then let the next passes read from that.
713                                         start_new_phase = true;
714                                 } else {
715                                         assert(deps[i]->effect->num_inputs() == 0);
716
717                                         // For textures, we try to be slightly more clever;
718                                         // if none of our outputs need a bounce, we don't bounce
719                                         // but instead simply use the effect many times.
720                                         //
721                                         // Strictly speaking, we could bounce it for some outputs
722                                         // and use it directly for others, but the processing becomes
723                                         // somewhat simpler if the effect is only used in one such way.
724                                         for (unsigned j = 0; j < deps[i]->outgoing_links.size(); ++j) {
725                                                 Node *rdep = deps[i]->outgoing_links[j];
726                                                 start_new_phase |= rdep->effect->needs_texture_bounce();
727                                         }
728                                 }
729                         }
730
731                         if (deps[i]->effect->is_compute_shader()) {
732                                 // Only one compute shader per phase; we should have been stopped
733                                 // already due to the fact that compute shaders are not one-to-one.
734                                 assert(!phase->is_compute_shader);
735
736                                 // If all nodes so far are strong one-to-one, we can put them after
737                                 // the compute shader (ie., process them on the output).
738                                 start_new_phase = !node->strong_one_to_one_sampling;
739                         } else if (deps[i]->effect->sets_virtual_output_size()) {
740                                 assert(deps[i]->effect->changes_output_size());
741                                 // If the next effect sets a virtual size to rely on OpenGL's
742                                 // bilinear sampling, we'll really need to break the phase here.
743                                 start_new_phase = true;
744                         } else if (deps[i]->effect->changes_output_size() && !node->one_to_one_sampling) {
745                                 // If the next effect changes size and we don't have one-to-one sampling,
746                                 // we also need to break here.
747                                 start_new_phase = true;
748                         }
749
750                         if (start_new_phase) {
751                                 phase->inputs.push_back(construct_phase(deps[i], completed_effects));
752                         } else {
753                                 effects_todo_this_phase.push(deps[i]);
754
755                                 // Propagate the one-to-one status down through the dependency.
756                                 deps[i]->one_to_one_sampling = node->one_to_one_sampling &&
757                                         deps[i]->effect->one_to_one_sampling();
758                                 deps[i]->strong_one_to_one_sampling = node->strong_one_to_one_sampling &&
759                                         deps[i]->effect->strong_one_to_one_sampling();
760                         }
761                 }
762         }
763
764         // No more effects to do this phase. Take all the ones we have,
765         // and create a GLSL program for it.
766         assert(!phase->effects.empty());
767
768         // Deduplicate the inputs, but don't change the ordering e.g. by sorting;
769         // that would be nondeterministic and thus reduce cacheability.
770         // TODO: Make this even more deterministic.
771         vector<Phase *> dedup_inputs;
772         set<Phase *> seen_inputs;
773         for (size_t i = 0; i < phase->inputs.size(); ++i) {
774                 if (seen_inputs.insert(phase->inputs[i]).second) {
775                         dedup_inputs.push_back(phase->inputs[i]);
776                 }
777         }
778         swap(phase->inputs, dedup_inputs);
779
780         // Allocate samplers for each input.
781         phase->input_samplers.resize(phase->inputs.size());
782
783         // We added the effects from the output and back, but we need to output
784         // them in topological sort order in the shader.
785         phase->effects = topological_sort(phase->effects);
786
787         // Figure out if we need mipmaps or not, and if so, tell the inputs that.
788         phase->input_needs_mipmaps = false;
789         for (unsigned i = 0; i < phase->effects.size(); ++i) {
790                 Node *node = phase->effects[i];
791                 phase->input_needs_mipmaps |= node->effect->needs_mipmaps();
792         }
793         for (unsigned i = 0; i < phase->effects.size(); ++i) {
794                 Node *node = phase->effects[i];
795                 if (node->effect->num_inputs() == 0) {
796                         Input *input = static_cast<Input *>(node->effect);
797                         assert(!phase->input_needs_mipmaps || input->can_supply_mipmaps());
798                         CHECK(input->set_int("needs_mipmaps", phase->input_needs_mipmaps));
799                 }
800         }
801
802         // Tell each node which phase it ended up in, so that the unit test
803         // can check that the phases were split in the right place.
804         // Note that this ignores that effects may be part of multiple phases;
805         // if the unit tests need to test such cases, we'll reconsider.
806         for (unsigned i = 0; i < phase->effects.size(); ++i) {
807                 phase->effects[i]->containing_phase = phase;
808         }
809
810         // Actually make the shader for this phase.
811         compile_glsl_program(phase);
812
813         // Initialize timers.
814         if (movit_timer_queries_supported) {
815                 phase->time_elapsed_ns = 0;
816                 phase->num_measured_iterations = 0;
817         }
818
819         assert(completed_effects->count(output) == 0);
820         completed_effects->insert(make_pair(output, phase));
821         phases.push_back(phase);
822         return phase;
823 }
824
825 void EffectChain::output_dot(const char *filename)
826 {
827         if (movit_debug_level != MOVIT_DEBUG_ON) {
828                 return;
829         }
830
831         FILE *fp = fopen(filename, "w");
832         if (fp == nullptr) {
833                 perror(filename);
834                 exit(1);
835         }
836
837         fprintf(fp, "digraph G {\n");
838         fprintf(fp, "  output [shape=box label=\"(output)\"];\n");
839         for (unsigned i = 0; i < nodes.size(); ++i) {
840                 // Find out which phase this event belongs to.
841                 vector<int> in_phases;
842                 for (unsigned j = 0; j < phases.size(); ++j) {
843                         const Phase* p = phases[j];
844                         if (find(p->effects.begin(), p->effects.end(), nodes[i]) != p->effects.end()) {
845                                 in_phases.push_back(j);
846                         }
847                 }
848
849                 if (in_phases.empty()) {
850                         fprintf(fp, "  n%ld [label=\"%s\"];\n", (long)nodes[i], nodes[i]->effect->effect_type_id().c_str());
851                 } else if (in_phases.size() == 1) {
852                         fprintf(fp, "  n%ld [label=\"%s\" style=\"filled\" fillcolor=\"/accent8/%d\"];\n",
853                                 (long)nodes[i], nodes[i]->effect->effect_type_id().c_str(),
854                                 (in_phases[0] % 8) + 1);
855                 } else {
856                         // If we had new enough Graphviz, style="wedged" would probably be ideal here.
857                         // But alas.
858                         fprintf(fp, "  n%ld [label=\"%s [in multiple phases]\" style=\"filled\" fillcolor=\"/accent8/%d\"];\n",
859                                 (long)nodes[i], nodes[i]->effect->effect_type_id().c_str(),
860                                 (in_phases[0] % 8) + 1);
861                 }
862
863                 char from_node_id[256];
864                 snprintf(from_node_id, 256, "n%ld", (long)nodes[i]);
865
866                 for (unsigned j = 0; j < nodes[i]->outgoing_links.size(); ++j) {
867                         char to_node_id[256];
868                         snprintf(to_node_id, 256, "n%ld", (long)nodes[i]->outgoing_links[j]);
869
870                         vector<string> labels = get_labels_for_edge(nodes[i], nodes[i]->outgoing_links[j]);
871                         output_dot_edge(fp, from_node_id, to_node_id, labels);
872                 }
873
874                 if (nodes[i]->outgoing_links.empty() && !nodes[i]->disabled) {
875                         // Output node.
876                         vector<string> labels = get_labels_for_edge(nodes[i], nullptr);
877                         output_dot_edge(fp, from_node_id, "output", labels);
878                 }
879         }
880         fprintf(fp, "}\n");
881
882         fclose(fp);
883 }
884
885 vector<string> EffectChain::get_labels_for_edge(const Node *from, const Node *to)
886 {
887         vector<string> labels;
888
889         if (to != nullptr && to->effect->needs_texture_bounce()) {
890                 labels.push_back("needs_bounce");
891         }
892         if (from->effect->changes_output_size()) {
893                 labels.push_back("resize");
894         }
895
896         switch (from->output_color_space) {
897         case COLORSPACE_INVALID:
898                 labels.push_back("spc[invalid]");
899                 break;
900         case COLORSPACE_REC_601_525:
901                 labels.push_back("spc[rec601-525]");
902                 break;
903         case COLORSPACE_REC_601_625:
904                 labels.push_back("spc[rec601-625]");
905                 break;
906         default:
907                 break;
908         }
909
910         switch (from->output_gamma_curve) {
911         case GAMMA_INVALID:
912                 labels.push_back("gamma[invalid]");
913                 break;
914         case GAMMA_sRGB:
915                 labels.push_back("gamma[sRGB]");
916                 break;
917         case GAMMA_REC_601:  // and GAMMA_REC_709
918                 labels.push_back("gamma[rec601/709]");
919                 break;
920         default:
921                 break;
922         }
923
924         switch (from->output_alpha_type) {
925         case ALPHA_INVALID:
926                 labels.push_back("alpha[invalid]");
927                 break;
928         case ALPHA_BLANK:
929                 labels.push_back("alpha[blank]");
930                 break;
931         case ALPHA_POSTMULTIPLIED:
932                 labels.push_back("alpha[postmult]");
933                 break;
934         default:
935                 break;
936         }
937
938         return labels;
939 }
940
941 void EffectChain::output_dot_edge(FILE *fp,
942                                   const string &from_node_id,
943                                   const string &to_node_id,
944                                   const vector<string> &labels)
945 {
946         if (labels.empty()) {
947                 fprintf(fp, "  %s -> %s;\n", from_node_id.c_str(), to_node_id.c_str());
948         } else {
949                 string label = labels[0];
950                 for (unsigned k = 1; k < labels.size(); ++k) {
951                         label += ", " + labels[k];
952                 }
953                 fprintf(fp, "  %s -> %s [label=\"%s\"];\n", from_node_id.c_str(), to_node_id.c_str(), label.c_str());
954         }
955 }
956
957 void EffectChain::size_rectangle_to_fit(unsigned width, unsigned height, unsigned *output_width, unsigned *output_height)
958 {
959         unsigned scaled_width, scaled_height;
960
961         if (float(width) * aspect_denom >= float(height) * aspect_nom) {
962                 // Same aspect, or W/H > aspect (image is wider than the frame).
963                 // In either case, keep width, and adjust height.
964                 scaled_width = width;
965                 scaled_height = lrintf(width * aspect_denom / aspect_nom);
966         } else {
967                 // W/H < aspect (image is taller than the frame), so keep height,
968                 // and adjust width.
969                 scaled_width = lrintf(height * aspect_nom / aspect_denom);
970                 scaled_height = height;
971         }
972
973         // We should be consistently larger or smaller then the existing choice,
974         // since we have the same aspect.
975         assert(!(scaled_width < *output_width && scaled_height > *output_height));
976         assert(!(scaled_height < *output_height && scaled_width > *output_width));
977
978         if (scaled_width >= *output_width && scaled_height >= *output_height) {
979                 *output_width = scaled_width;
980                 *output_height = scaled_height;
981         }
982 }
983
984 // Propagate input texture sizes throughout, and inform effects downstream.
985 // (Like a lot of other code, we depend on effects being in topological order.)
986 void EffectChain::inform_input_sizes(Phase *phase)
987 {
988         // All effects that have a defined size (inputs and RTT inputs)
989         // get that. Reset all others.
990         for (unsigned i = 0; i < phase->effects.size(); ++i) {
991                 Node *node = phase->effects[i];
992                 if (node->effect->num_inputs() == 0) {
993                         Input *input = static_cast<Input *>(node->effect);
994                         node->output_width = input->get_width();
995                         node->output_height = input->get_height();
996                         assert(node->output_width != 0);
997                         assert(node->output_height != 0);
998                 } else {
999                         node->output_width = node->output_height = 0;
1000                 }
1001         }
1002         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
1003                 Phase *input = phase->inputs[i];
1004                 input->output_node->output_width = input->virtual_output_width;
1005                 input->output_node->output_height = input->virtual_output_height;
1006                 assert(input->output_node->output_width != 0);
1007                 assert(input->output_node->output_height != 0);
1008         }
1009
1010         // Now propagate from the inputs towards the end, and inform as we go.
1011         // The rules are simple:
1012         //
1013         //   1. Don't touch effects that already have given sizes (ie., inputs
1014         //      or effects that change the output size).
1015         //   2. If all of your inputs have the same size, that will be your output size.
1016         //   3. Otherwise, your output size is 0x0.
1017         for (unsigned i = 0; i < phase->effects.size(); ++i) {
1018                 Node *node = phase->effects[i];
1019                 if (node->effect->num_inputs() == 0) {
1020                         continue;
1021                 }
1022                 unsigned this_output_width = 0;
1023                 unsigned this_output_height = 0;
1024                 for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
1025                         Node *input = node->incoming_links[j];
1026                         node->effect->inform_input_size(j, input->output_width, input->output_height);
1027                         if (j == 0) {
1028                                 this_output_width = input->output_width;
1029                                 this_output_height = input->output_height;
1030                         } else if (input->output_width != this_output_width || input->output_height != this_output_height) {
1031                                 // Inputs disagree.
1032                                 this_output_width = 0;
1033                                 this_output_height = 0;
1034                         }
1035                 }
1036                 if (node->effect->changes_output_size()) {
1037                         // We cannot call get_output_size() before we've done inform_input_size()
1038                         // on all inputs.
1039                         unsigned real_width, real_height;
1040                         node->effect->get_output_size(&real_width, &real_height,
1041                                                       &node->output_width, &node->output_height);
1042                         assert(node->effect->sets_virtual_output_size() ||
1043                                (real_width == node->output_width &&
1044                                 real_height == node->output_height));
1045                 } else {
1046                         node->output_width = this_output_width;
1047                         node->output_height = this_output_height;
1048                 }
1049         }
1050 }
1051
1052 // Note: You should call inform_input_sizes() before this, as the last effect's
1053 // desired output size might change based on the inputs.
1054 void EffectChain::find_output_size(Phase *phase)
1055 {
1056         Node *output_node = phase->is_compute_shader ? phase->compute_shader_node : phase->effects.back();
1057
1058         // If the last effect explicitly sets an output size, use that.
1059         if (output_node->effect->changes_output_size()) {
1060                 output_node->effect->get_output_size(&phase->output_width, &phase->output_height,
1061                                                      &phase->virtual_output_width, &phase->virtual_output_height);
1062                 assert(output_node->effect->sets_virtual_output_size() ||
1063                        (phase->output_width == phase->virtual_output_width &&
1064                         phase->output_height == phase->virtual_output_height));
1065                 return;
1066         }
1067
1068         // If all effects have the same size, use that.
1069         unsigned output_width = 0, output_height = 0;
1070         bool all_inputs_same_size = true;
1071
1072         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
1073                 Phase *input = phase->inputs[i];
1074                 assert(input->output_width != 0);
1075                 assert(input->output_height != 0);
1076                 if (output_width == 0 && output_height == 0) {
1077                         output_width = input->virtual_output_width;
1078                         output_height = input->virtual_output_height;
1079                 } else if (output_width != input->virtual_output_width ||
1080                            output_height != input->virtual_output_height) {
1081                         all_inputs_same_size = false;
1082                 }
1083         }
1084         for (unsigned i = 0; i < phase->effects.size(); ++i) {
1085                 Effect *effect = phase->effects[i]->effect;
1086                 if (effect->num_inputs() != 0) {
1087                         continue;
1088                 }
1089
1090                 Input *input = static_cast<Input *>(effect);
1091                 if (output_width == 0 && output_height == 0) {
1092                         output_width = input->get_width();
1093                         output_height = input->get_height();
1094                 } else if (output_width != input->get_width() ||
1095                            output_height != input->get_height()) {
1096                         all_inputs_same_size = false;
1097                 }
1098         }
1099
1100         if (all_inputs_same_size) {
1101                 assert(output_width != 0);
1102                 assert(output_height != 0);
1103                 phase->virtual_output_width = phase->output_width = output_width;
1104                 phase->virtual_output_height = phase->output_height = output_height;
1105                 return;
1106         }
1107
1108         // If not, fit all the inputs into the current aspect, and select the largest one. 
1109         output_width = 0;
1110         output_height = 0;
1111         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
1112                 Phase *input = phase->inputs[i];
1113                 assert(input->output_width != 0);
1114                 assert(input->output_height != 0);
1115                 size_rectangle_to_fit(input->output_width, input->output_height, &output_width, &output_height);
1116         }
1117         for (unsigned i = 0; i < phase->effects.size(); ++i) {
1118                 Effect *effect = phase->effects[i]->effect;
1119                 if (effect->num_inputs() != 0) {
1120                         continue;
1121                 }
1122
1123                 Input *input = static_cast<Input *>(effect);
1124                 size_rectangle_to_fit(input->get_width(), input->get_height(), &output_width, &output_height);
1125         }
1126         assert(output_width != 0);
1127         assert(output_height != 0);
1128         phase->virtual_output_width = phase->output_width = output_width;
1129         phase->virtual_output_height = phase->output_height = output_height;
1130 }
1131
1132 void EffectChain::sort_all_nodes_topologically()
1133 {
1134         nodes = topological_sort(nodes);
1135 }
1136
1137 vector<Node *> EffectChain::topological_sort(const vector<Node *> &nodes)
1138 {
1139         set<Node *> nodes_left_to_visit(nodes.begin(), nodes.end());
1140         vector<Node *> sorted_list;
1141         for (unsigned i = 0; i < nodes.size(); ++i) {
1142                 topological_sort_visit_node(nodes[i], &nodes_left_to_visit, &sorted_list);
1143         }
1144         reverse(sorted_list.begin(), sorted_list.end());
1145         return sorted_list;
1146 }
1147
1148 void EffectChain::topological_sort_visit_node(Node *node, set<Node *> *nodes_left_to_visit, vector<Node *> *sorted_list)
1149 {
1150         if (nodes_left_to_visit->count(node) == 0) {
1151                 return;
1152         }
1153         nodes_left_to_visit->erase(node);
1154         for (unsigned i = 0; i < node->outgoing_links.size(); ++i) {
1155                 topological_sort_visit_node(node->outgoing_links[i], nodes_left_to_visit, sorted_list);
1156         }
1157         sorted_list->push_back(node);
1158 }
1159
1160 void EffectChain::find_color_spaces_for_inputs()
1161 {
1162         for (unsigned i = 0; i < nodes.size(); ++i) {
1163                 Node *node = nodes[i];
1164                 if (node->disabled) {
1165                         continue;
1166                 }
1167                 if (node->incoming_links.size() == 0) {
1168                         Input *input = static_cast<Input *>(node->effect);
1169                         node->output_color_space = input->get_color_space();
1170                         node->output_gamma_curve = input->get_gamma_curve();
1171
1172                         Effect::AlphaHandling alpha_handling = input->alpha_handling();
1173                         switch (alpha_handling) {
1174                         case Effect::OUTPUT_BLANK_ALPHA:
1175                                 node->output_alpha_type = ALPHA_BLANK;
1176                                 break;
1177                         case Effect::INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA:
1178                                 node->output_alpha_type = ALPHA_PREMULTIPLIED;
1179                                 break;
1180                         case Effect::OUTPUT_POSTMULTIPLIED_ALPHA:
1181                                 node->output_alpha_type = ALPHA_POSTMULTIPLIED;
1182                                 break;
1183                         case Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK:
1184                         case Effect::DONT_CARE_ALPHA_TYPE:
1185                         default:
1186                                 assert(false);
1187                         }
1188
1189                         if (node->output_alpha_type == ALPHA_PREMULTIPLIED) {
1190                                 assert(node->output_gamma_curve == GAMMA_LINEAR);
1191                         }
1192                 }
1193         }
1194 }
1195
1196 // Propagate gamma and color space information as far as we can in the graph.
1197 // The rules are simple: Anything where all the inputs agree, get that as
1198 // output as well. Anything else keeps having *_INVALID.
1199 void EffectChain::propagate_gamma_and_color_space()
1200 {
1201         // We depend on going through the nodes in order.
1202         sort_all_nodes_topologically();
1203
1204         for (unsigned i = 0; i < nodes.size(); ++i) {
1205                 Node *node = nodes[i];
1206                 if (node->disabled) {
1207                         continue;
1208                 }
1209                 assert(node->incoming_links.size() == node->effect->num_inputs());
1210                 if (node->incoming_links.size() == 0) {
1211                         assert(node->output_color_space != COLORSPACE_INVALID);
1212                         assert(node->output_gamma_curve != GAMMA_INVALID);
1213                         continue;
1214                 }
1215
1216                 Colorspace color_space = node->incoming_links[0]->output_color_space;
1217                 GammaCurve gamma_curve = node->incoming_links[0]->output_gamma_curve;
1218                 for (unsigned j = 1; j < node->incoming_links.size(); ++j) {
1219                         if (node->incoming_links[j]->output_color_space != color_space) {
1220                                 color_space = COLORSPACE_INVALID;
1221                         }
1222                         if (node->incoming_links[j]->output_gamma_curve != gamma_curve) {
1223                                 gamma_curve = GAMMA_INVALID;
1224                         }
1225                 }
1226
1227                 // The conversion effects already have their outputs set correctly,
1228                 // so leave them alone.
1229                 if (node->effect->effect_type_id() != "ColorspaceConversionEffect") {
1230                         node->output_color_space = color_space;
1231                 }               
1232                 if (node->effect->effect_type_id() != "GammaCompressionEffect" &&
1233                     node->effect->effect_type_id() != "GammaExpansionEffect") {
1234                         node->output_gamma_curve = gamma_curve;
1235                 }               
1236         }
1237 }
1238
1239 // Propagate alpha information as far as we can in the graph.
1240 // Similar to propagate_gamma_and_color_space().
1241 void EffectChain::propagate_alpha()
1242 {
1243         // We depend on going through the nodes in order.
1244         sort_all_nodes_topologically();
1245
1246         for (unsigned i = 0; i < nodes.size(); ++i) {
1247                 Node *node = nodes[i];
1248                 if (node->disabled) {
1249                         continue;
1250                 }
1251                 assert(node->incoming_links.size() == node->effect->num_inputs());
1252                 if (node->incoming_links.size() == 0) {
1253                         assert(node->output_alpha_type != ALPHA_INVALID);
1254                         continue;
1255                 }
1256
1257                 // The alpha multiplication/division effects are special cases.
1258                 if (node->effect->effect_type_id() == "AlphaMultiplicationEffect") {
1259                         assert(node->incoming_links.size() == 1);
1260                         assert(node->incoming_links[0]->output_alpha_type == ALPHA_POSTMULTIPLIED);
1261                         node->output_alpha_type = ALPHA_PREMULTIPLIED;
1262                         continue;
1263                 }
1264                 if (node->effect->effect_type_id() == "AlphaDivisionEffect") {
1265                         assert(node->incoming_links.size() == 1);
1266                         assert(node->incoming_links[0]->output_alpha_type == ALPHA_PREMULTIPLIED);
1267                         node->output_alpha_type = ALPHA_POSTMULTIPLIED;
1268                         continue;
1269                 }
1270
1271                 // GammaCompressionEffect and GammaExpansionEffect are also a special case,
1272                 // because they are the only one that _need_ postmultiplied alpha.
1273                 if (node->effect->effect_type_id() == "GammaCompressionEffect" ||
1274                     node->effect->effect_type_id() == "GammaExpansionEffect") {
1275                         assert(node->incoming_links.size() == 1);
1276                         if (node->incoming_links[0]->output_alpha_type == ALPHA_BLANK) {
1277                                 node->output_alpha_type = ALPHA_BLANK;
1278                         } else if (node->incoming_links[0]->output_alpha_type == ALPHA_POSTMULTIPLIED) {
1279                                 node->output_alpha_type = ALPHA_POSTMULTIPLIED;
1280                         } else {
1281                                 node->output_alpha_type = ALPHA_INVALID;
1282                         }
1283                         continue;
1284                 }
1285
1286                 // Only inputs can have unconditional alpha output (OUTPUT_BLANK_ALPHA
1287                 // or OUTPUT_POSTMULTIPLIED_ALPHA), and they have already been
1288                 // taken care of above. Rationale: Even if you could imagine
1289                 // e.g. an effect that took in an image and set alpha=1.0
1290                 // unconditionally, it wouldn't make any sense to have it as
1291                 // e.g. OUTPUT_BLANK_ALPHA, since it wouldn't know whether it
1292                 // got its input pre- or postmultiplied, so it wouldn't know
1293                 // whether to divide away the old alpha or not.
1294                 Effect::AlphaHandling alpha_handling = node->effect->alpha_handling();
1295                 assert(alpha_handling == Effect::INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA ||
1296                        alpha_handling == Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK ||
1297                        alpha_handling == Effect::DONT_CARE_ALPHA_TYPE);
1298
1299                 // If the node has multiple inputs, check that they are all valid and
1300                 // the same.
1301                 bool any_invalid = false;
1302                 bool any_premultiplied = false;
1303                 bool any_postmultiplied = false;
1304
1305                 for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
1306                         switch (node->incoming_links[j]->output_alpha_type) {
1307                         case ALPHA_INVALID:
1308                                 any_invalid = true;
1309                                 break;
1310                         case ALPHA_BLANK:
1311                                 // Blank is good as both pre- and postmultiplied alpha,
1312                                 // so just ignore it.
1313                                 break;
1314                         case ALPHA_PREMULTIPLIED:
1315                                 any_premultiplied = true;
1316                                 break;
1317                         case ALPHA_POSTMULTIPLIED:
1318                                 any_postmultiplied = true;
1319                                 break;
1320                         default:
1321                                 assert(false);
1322                         }
1323                 }
1324
1325                 if (any_invalid) {
1326                         node->output_alpha_type = ALPHA_INVALID;
1327                         continue;
1328                 }
1329
1330                 // Inputs must be of the same type.
1331                 if (any_premultiplied && any_postmultiplied) {
1332                         node->output_alpha_type = ALPHA_INVALID;
1333                         continue;
1334                 }
1335
1336                 if (alpha_handling == Effect::INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA ||
1337                     alpha_handling == Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK) {
1338                         // This combination (requiring premultiplied alpha, but _not_ requiring
1339                         // linear light) is illegal, since the combination of premultiplied alpha
1340                         // and nonlinear inputs is meaningless.
1341                         assert(node->effect->needs_linear_light());
1342
1343                         // If the effect has asked for premultiplied alpha, check that it has got it.
1344                         if (any_postmultiplied) {
1345                                 node->output_alpha_type = ALPHA_INVALID;
1346                         } else if (!any_premultiplied &&
1347                                    alpha_handling == Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK) {
1348                                 // Blank input alpha, and the effect preserves blank alpha.
1349                                 node->output_alpha_type = ALPHA_BLANK;
1350                         } else {
1351                                 node->output_alpha_type = ALPHA_PREMULTIPLIED;
1352                         }
1353                 } else {
1354                         // OK, all inputs are the same, and this effect is not going
1355                         // to change it.
1356                         assert(alpha_handling == Effect::DONT_CARE_ALPHA_TYPE);
1357                         if (any_premultiplied) {
1358                                 node->output_alpha_type = ALPHA_PREMULTIPLIED;
1359                         } else if (any_postmultiplied) {
1360                                 node->output_alpha_type = ALPHA_POSTMULTIPLIED;
1361                         } else {
1362                                 node->output_alpha_type = ALPHA_BLANK;
1363                         }
1364                 }
1365         }
1366 }
1367
1368 bool EffectChain::node_needs_colorspace_fix(Node *node)
1369 {
1370         if (node->disabled) {
1371                 return false;
1372         }
1373         if (node->effect->num_inputs() == 0) {
1374                 return false;
1375         }
1376
1377         // propagate_gamma_and_color_space() has already set our output
1378         // to COLORSPACE_INVALID if the inputs differ, so we can rely on that.
1379         if (node->output_color_space == COLORSPACE_INVALID) {
1380                 return true;
1381         }
1382         return (node->effect->needs_srgb_primaries() && node->output_color_space != COLORSPACE_sRGB);
1383 }
1384
1385 // Fix up color spaces so that there are no COLORSPACE_INVALID nodes left in
1386 // the graph. Our strategy is not always optimal, but quite simple:
1387 // Find an effect that's as early as possible where the inputs are of
1388 // unacceptable colorspaces (that is, either different, or, if the effect only
1389 // wants sRGB, not sRGB.) Add appropriate conversions on all its inputs,
1390 // propagate the information anew, and repeat until there are no more such
1391 // effects.
1392 void EffectChain::fix_internal_color_spaces()
1393 {
1394         unsigned colorspace_propagation_pass = 0;
1395         bool found_any;
1396         do {
1397                 found_any = false;
1398                 for (unsigned i = 0; i < nodes.size(); ++i) {
1399                         Node *node = nodes[i];
1400                         if (!node_needs_colorspace_fix(node)) {
1401                                 continue;
1402                         }
1403
1404                         // Go through each input that is not sRGB, and insert
1405                         // a colorspace conversion after it.
1406                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
1407                                 Node *input = node->incoming_links[j];
1408                                 assert(input->output_color_space != COLORSPACE_INVALID);
1409                                 if (input->output_color_space == COLORSPACE_sRGB) {
1410                                         continue;
1411                                 }
1412                                 Node *conversion = add_node(new ColorspaceConversionEffect());
1413                                 CHECK(conversion->effect->set_int("source_space", input->output_color_space));
1414                                 CHECK(conversion->effect->set_int("destination_space", COLORSPACE_sRGB));
1415                                 conversion->output_color_space = COLORSPACE_sRGB;
1416                                 replace_sender(input, conversion);
1417                                 connect_nodes(input, conversion);
1418                         }
1419
1420                         // Re-sort topologically, and propagate the new information.
1421                         propagate_gamma_and_color_space();
1422                         
1423                         found_any = true;
1424                         break;
1425                 }
1426         
1427                 char filename[256];
1428                 sprintf(filename, "step5-colorspacefix-iter%u.dot", ++colorspace_propagation_pass);
1429                 output_dot(filename);
1430                 assert(colorspace_propagation_pass < 100);
1431         } while (found_any);
1432
1433         for (unsigned i = 0; i < nodes.size(); ++i) {
1434                 Node *node = nodes[i];
1435                 if (node->disabled) {
1436                         continue;
1437                 }
1438                 assert(node->output_color_space != COLORSPACE_INVALID);
1439         }
1440 }
1441
1442 bool EffectChain::node_needs_alpha_fix(Node *node)
1443 {
1444         if (node->disabled) {
1445                 return false;
1446         }
1447
1448         // propagate_alpha() has already set our output to ALPHA_INVALID if the
1449         // inputs differ or we are otherwise in mismatch, so we can rely on that.
1450         return (node->output_alpha_type == ALPHA_INVALID);
1451 }
1452
1453 // Fix up alpha so that there are no ALPHA_INVALID nodes left in
1454 // the graph. Similar to fix_internal_color_spaces().
1455 void EffectChain::fix_internal_alpha(unsigned step)
1456 {
1457         unsigned alpha_propagation_pass = 0;
1458         bool found_any;
1459         do {
1460                 found_any = false;
1461                 for (unsigned i = 0; i < nodes.size(); ++i) {
1462                         Node *node = nodes[i];
1463                         if (!node_needs_alpha_fix(node)) {
1464                                 continue;
1465                         }
1466
1467                         // If we need to fix up GammaExpansionEffect, then clearly something
1468                         // is wrong, since the combination of premultiplied alpha and nonlinear inputs
1469                         // is meaningless.
1470                         assert(node->effect->effect_type_id() != "GammaExpansionEffect");
1471
1472                         AlphaType desired_type = ALPHA_PREMULTIPLIED;
1473
1474                         // GammaCompressionEffect is special; it needs postmultiplied alpha.
1475                         if (node->effect->effect_type_id() == "GammaCompressionEffect") {
1476                                 assert(node->incoming_links.size() == 1);
1477                                 assert(node->incoming_links[0]->output_alpha_type == ALPHA_PREMULTIPLIED);
1478                                 desired_type = ALPHA_POSTMULTIPLIED;
1479                         }
1480
1481                         // Go through each input that is not premultiplied alpha, and insert
1482                         // a conversion before it.
1483                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
1484                                 Node *input = node->incoming_links[j];
1485                                 assert(input->output_alpha_type != ALPHA_INVALID);
1486                                 if (input->output_alpha_type == desired_type ||
1487                                     input->output_alpha_type == ALPHA_BLANK) {
1488                                         continue;
1489                                 }
1490                                 Node *conversion;
1491                                 if (desired_type == ALPHA_PREMULTIPLIED) {
1492                                         conversion = add_node(new AlphaMultiplicationEffect());
1493                                 } else {
1494                                         conversion = add_node(new AlphaDivisionEffect());
1495                                 }
1496                                 conversion->output_alpha_type = desired_type;
1497                                 replace_sender(input, conversion);
1498                                 connect_nodes(input, conversion);
1499                         }
1500
1501                         // Re-sort topologically, and propagate the new information.
1502                         propagate_gamma_and_color_space();
1503                         propagate_alpha();
1504                         
1505                         found_any = true;
1506                         break;
1507                 }
1508         
1509                 char filename[256];
1510                 sprintf(filename, "step%u-alphafix-iter%u.dot", step, ++alpha_propagation_pass);
1511                 output_dot(filename);
1512                 assert(alpha_propagation_pass < 100);
1513         } while (found_any);
1514
1515         for (unsigned i = 0; i < nodes.size(); ++i) {
1516                 Node *node = nodes[i];
1517                 if (node->disabled) {
1518                         continue;
1519                 }
1520                 assert(node->output_alpha_type != ALPHA_INVALID);
1521         }
1522 }
1523
1524 // Make so that the output is in the desired color space.
1525 void EffectChain::fix_output_color_space()
1526 {
1527         Node *output = find_output_node();
1528         if (output->output_color_space != output_format.color_space) {
1529                 Node *conversion = add_node(new ColorspaceConversionEffect());
1530                 CHECK(conversion->effect->set_int("source_space", output->output_color_space));
1531                 CHECK(conversion->effect->set_int("destination_space", output_format.color_space));
1532                 conversion->output_color_space = output_format.color_space;
1533                 connect_nodes(output, conversion);
1534                 propagate_alpha();
1535                 propagate_gamma_and_color_space();
1536         }
1537 }
1538
1539 // Make so that the output is in the desired pre-/postmultiplication alpha state.
1540 void EffectChain::fix_output_alpha()
1541 {
1542         Node *output = find_output_node();
1543         assert(output->output_alpha_type != ALPHA_INVALID);
1544         if (output->output_alpha_type == ALPHA_BLANK) {
1545                 // No alpha output, so we don't care.
1546                 return;
1547         }
1548         if (output->output_alpha_type == ALPHA_PREMULTIPLIED &&
1549             output_alpha_format == OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED) {
1550                 Node *conversion = add_node(new AlphaDivisionEffect());
1551                 connect_nodes(output, conversion);
1552                 propagate_alpha();
1553                 propagate_gamma_and_color_space();
1554         }
1555         if (output->output_alpha_type == ALPHA_POSTMULTIPLIED &&
1556             output_alpha_format == OUTPUT_ALPHA_FORMAT_PREMULTIPLIED) {
1557                 Node *conversion = add_node(new AlphaMultiplicationEffect());
1558                 connect_nodes(output, conversion);
1559                 propagate_alpha();
1560                 propagate_gamma_and_color_space();
1561         }
1562 }
1563
1564 bool EffectChain::node_needs_gamma_fix(Node *node)
1565 {
1566         if (node->disabled) {
1567                 return false;
1568         }
1569
1570         // Small hack since the output is not an explicit node:
1571         // If we are the last node and our output is in the wrong
1572         // space compared to EffectChain's output, we need to fix it.
1573         // This will only take us to linear, but fix_output_gamma()
1574         // will come and take us to the desired output gamma
1575         // if it is needed.
1576         //
1577         // This needs to be before everything else, since it could
1578         // even apply to inputs (if they are the only effect).
1579         if (node->outgoing_links.empty() &&
1580             node->output_gamma_curve != output_format.gamma_curve &&
1581             node->output_gamma_curve != GAMMA_LINEAR) {
1582                 return true;
1583         }
1584
1585         if (node->effect->num_inputs() == 0) {
1586                 return false;
1587         }
1588
1589         // propagate_gamma_and_color_space() has already set our output
1590         // to GAMMA_INVALID if the inputs differ, so we can rely on that,
1591         // except for GammaCompressionEffect.
1592         if (node->output_gamma_curve == GAMMA_INVALID) {
1593                 return true;
1594         }
1595         if (node->effect->effect_type_id() == "GammaCompressionEffect") {
1596                 assert(node->incoming_links.size() == 1);
1597                 return node->incoming_links[0]->output_gamma_curve != GAMMA_LINEAR;
1598         }
1599
1600         return (node->effect->needs_linear_light() && node->output_gamma_curve != GAMMA_LINEAR);
1601 }
1602
1603 // Very similar to fix_internal_color_spaces(), but for gamma.
1604 // There is one difference, though; before we start adding conversion nodes,
1605 // we see if we can get anything out of asking the sources to deliver
1606 // linear gamma directly. fix_internal_gamma_by_asking_inputs()
1607 // does that part, while fix_internal_gamma_by_inserting_nodes()
1608 // inserts nodes as needed afterwards.
1609 void EffectChain::fix_internal_gamma_by_asking_inputs(unsigned step)
1610 {
1611         unsigned gamma_propagation_pass = 0;
1612         bool found_any;
1613         do {
1614                 found_any = false;
1615                 for (unsigned i = 0; i < nodes.size(); ++i) {
1616                         Node *node = nodes[i];
1617                         if (!node_needs_gamma_fix(node)) {
1618                                 continue;
1619                         }
1620
1621                         // See if all inputs can give us linear gamma. If not, leave it.
1622                         vector<Node *> nonlinear_inputs;
1623                         find_all_nonlinear_inputs(node, &nonlinear_inputs);
1624                         assert(!nonlinear_inputs.empty());
1625
1626                         bool all_ok = true;
1627                         for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
1628                                 Input *input = static_cast<Input *>(nonlinear_inputs[i]->effect);
1629                                 all_ok &= input->can_output_linear_gamma();
1630                         }
1631
1632                         if (!all_ok) {
1633                                 continue;
1634                         }
1635
1636                         for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
1637                                 CHECK(nonlinear_inputs[i]->effect->set_int("output_linear_gamma", 1));
1638                                 nonlinear_inputs[i]->output_gamma_curve = GAMMA_LINEAR;
1639                         }
1640
1641                         // Re-sort topologically, and propagate the new information.
1642                         propagate_gamma_and_color_space();
1643                         
1644                         found_any = true;
1645                         break;
1646                 }
1647         
1648                 char filename[256];
1649                 sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
1650                 output_dot(filename);
1651                 assert(gamma_propagation_pass < 100);
1652         } while (found_any);
1653 }
1654
1655 void EffectChain::fix_internal_gamma_by_inserting_nodes(unsigned step)
1656 {
1657         unsigned gamma_propagation_pass = 0;
1658         bool found_any;
1659         do {
1660                 found_any = false;
1661                 for (unsigned i = 0; i < nodes.size(); ++i) {
1662                         Node *node = nodes[i];
1663                         if (!node_needs_gamma_fix(node)) {
1664                                 continue;
1665                         }
1666
1667                         // Special case: We could be an input and still be asked to
1668                         // fix our gamma; if so, we should be the only node
1669                         // (as node_needs_gamma_fix() would only return true in
1670                         // for an input in that case). That means we should insert
1671                         // a conversion node _after_ ourselves.
1672                         if (node->incoming_links.empty()) {
1673                                 assert(node->outgoing_links.empty());
1674                                 Node *conversion = add_node(new GammaExpansionEffect());
1675                                 CHECK(conversion->effect->set_int("source_curve", node->output_gamma_curve));
1676                                 conversion->output_gamma_curve = GAMMA_LINEAR;
1677                                 connect_nodes(node, conversion);
1678                         }
1679
1680                         // If not, go through each input that is not linear gamma,
1681                         // and insert a gamma conversion after it.
1682                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
1683                                 Node *input = node->incoming_links[j];
1684                                 assert(input->output_gamma_curve != GAMMA_INVALID);
1685                                 if (input->output_gamma_curve == GAMMA_LINEAR) {
1686                                         continue;
1687                                 }
1688                                 Node *conversion = add_node(new GammaExpansionEffect());
1689                                 CHECK(conversion->effect->set_int("source_curve", input->output_gamma_curve));
1690                                 conversion->output_gamma_curve = GAMMA_LINEAR;
1691                                 replace_sender(input, conversion);
1692                                 connect_nodes(input, conversion);
1693                         }
1694
1695                         // Re-sort topologically, and propagate the new information.
1696                         propagate_alpha();
1697                         propagate_gamma_and_color_space();
1698                         
1699                         found_any = true;
1700                         break;
1701                 }
1702         
1703                 char filename[256];
1704                 sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
1705                 output_dot(filename);
1706                 assert(gamma_propagation_pass < 100);
1707         } while (found_any);
1708
1709         for (unsigned i = 0; i < nodes.size(); ++i) {
1710                 Node *node = nodes[i];
1711                 if (node->disabled) {
1712                         continue;
1713                 }
1714                 assert(node->output_gamma_curve != GAMMA_INVALID);
1715         }
1716 }
1717
1718 // Make so that the output is in the desired gamma.
1719 // Note that this assumes linear input gamma, so it might create the need
1720 // for another pass of fix_internal_gamma().
1721 void EffectChain::fix_output_gamma()
1722 {
1723         Node *output = find_output_node();
1724         if (output->output_gamma_curve != output_format.gamma_curve) {
1725                 Node *conversion = add_node(new GammaCompressionEffect());
1726                 CHECK(conversion->effect->set_int("destination_curve", output_format.gamma_curve));
1727                 conversion->output_gamma_curve = output_format.gamma_curve;
1728                 connect_nodes(output, conversion);
1729         }
1730 }
1731
1732 // If the user has requested Y'CbCr output, we need to do this conversion
1733 // _after_ GammaCompressionEffect etc., but before dither (see below).
1734 // This is because Y'CbCr, with the exception of a special optional mode
1735 // in Rec. 2020 (which we currently don't support), is defined to work on
1736 // gamma-encoded data.
1737 void EffectChain::add_ycbcr_conversion_if_needed()
1738 {
1739         assert(output_color_rgba || num_output_color_ycbcr > 0);
1740         if (num_output_color_ycbcr == 0) {
1741                 return;
1742         }
1743         Node *output = find_output_node();
1744         ycbcr_conversion_effect_node = add_node(new YCbCrConversionEffect(output_ycbcr_format, output_ycbcr_type));
1745         connect_nodes(output, ycbcr_conversion_effect_node);
1746 }
1747         
1748 // If the user has requested dither, add a DitherEffect right at the end
1749 // (after GammaCompressionEffect etc.). This needs to be done after everything else,
1750 // since dither is about the only effect that can _not_ be done in linear space.
1751 void EffectChain::add_dither_if_needed()
1752 {
1753         if (num_dither_bits == 0) {
1754                 return;
1755         }
1756         Node *output = find_output_node();
1757         Node *dither = add_node(new DitherEffect());
1758         CHECK(dither->effect->set_int("num_bits", num_dither_bits));
1759         connect_nodes(output, dither);
1760
1761         dither_effect = dither->effect;
1762 }
1763
1764 // Compute shaders can't output to the framebuffer, so if the last
1765 // phase ends in a compute shader, add a dummy phase at the end that
1766 // only blits directly from the temporary texture.
1767 //
1768 // TODO: Add an API for rendering directly to textures, for the cases
1769 // where we're only rendering to an FBO anyway.
1770 void EffectChain::add_dummy_effect_if_needed()
1771 {
1772         Node *output = find_output_node();
1773
1774         // See if the last effect that's not strong one-to-one is a compute shader.
1775         Node *last_effect = output;
1776         while (last_effect->effect->num_inputs() == 1 &&
1777                last_effect->effect->strong_one_to_one_sampling()) {
1778                 last_effect = last_effect->incoming_links[0];
1779         }
1780         if (last_effect->effect->is_compute_shader()) {
1781                 Node *dummy = add_node(new ComputeShaderOutputDisplayEffect());
1782                 connect_nodes(output, dummy);
1783                 has_dummy_effect = true;
1784         }
1785 }
1786
1787 // Find the output node. This is, simply, one that has no outgoing links.
1788 // If there are multiple ones, the graph is malformed (we do not support
1789 // multiple outputs right now).
1790 Node *EffectChain::find_output_node()
1791 {
1792         vector<Node *> output_nodes;
1793         for (unsigned i = 0; i < nodes.size(); ++i) {
1794                 Node *node = nodes[i];
1795                 if (node->disabled) {
1796                         continue;
1797                 }
1798                 if (node->outgoing_links.empty()) {
1799                         output_nodes.push_back(node);
1800                 }
1801         }
1802         assert(output_nodes.size() == 1);
1803         return output_nodes[0];
1804 }
1805
1806 void EffectChain::finalize()
1807 {
1808         // Output the graph as it is before we do any conversions on it.
1809         output_dot("step0-start.dot");
1810
1811         // Give each effect in turn a chance to rewrite its own part of the graph.
1812         // Note that if more effects are added as part of this, they will be
1813         // picked up as part of the same for loop, since they are added at the end.
1814         for (unsigned i = 0; i < nodes.size(); ++i) {
1815                 nodes[i]->effect->rewrite_graph(this, nodes[i]);
1816         }
1817         output_dot("step1-rewritten.dot");
1818
1819         find_color_spaces_for_inputs();
1820         output_dot("step2-input-colorspace.dot");
1821
1822         propagate_alpha();
1823         output_dot("step3-propagated-alpha.dot");
1824
1825         propagate_gamma_and_color_space();
1826         output_dot("step4-propagated-all.dot");
1827
1828         fix_internal_color_spaces();
1829         fix_internal_alpha(6);
1830         fix_output_color_space();
1831         output_dot("step7-output-colorspacefix.dot");
1832         fix_output_alpha();
1833         output_dot("step8-output-alphafix.dot");
1834
1835         // Note that we need to fix gamma after colorspace conversion,
1836         // because colorspace conversions might create needs for gamma conversions.
1837         // Also, we need to run an extra pass of fix_internal_gamma() after 
1838         // fixing the output gamma, as we only have conversions to/from linear,
1839         // and fix_internal_alpha() since GammaCompressionEffect needs
1840         // postmultiplied input.
1841         fix_internal_gamma_by_asking_inputs(9);
1842         fix_internal_gamma_by_inserting_nodes(10);
1843         fix_output_gamma();
1844         output_dot("step11-output-gammafix.dot");
1845         propagate_alpha();
1846         output_dot("step12-output-alpha-propagated.dot");
1847         fix_internal_alpha(13);
1848         output_dot("step14-output-alpha-fixed.dot");
1849         fix_internal_gamma_by_asking_inputs(15);
1850         fix_internal_gamma_by_inserting_nodes(16);
1851
1852         output_dot("step17-before-ycbcr.dot");
1853         add_ycbcr_conversion_if_needed();
1854
1855         output_dot("step18-before-dither.dot");
1856         add_dither_if_needed();
1857
1858         output_dot("step19-before-dummy-effect.dot");
1859         add_dummy_effect_if_needed();
1860
1861         output_dot("step20-final.dot");
1862         
1863         // Construct all needed GLSL programs, starting at the output.
1864         // We need to keep track of which effects have already been computed,
1865         // as an effect with multiple users could otherwise be calculated
1866         // multiple times.
1867         map<Node *, Phase *> completed_effects;
1868         construct_phase(find_output_node(), &completed_effects);
1869
1870         output_dot("step21-split-to-phases.dot");
1871
1872         assert(phases[0]->inputs.empty());
1873         
1874         finalized = true;
1875 }
1876
1877 void EffectChain::render_to_fbo(GLuint dest_fbo, unsigned width, unsigned height)
1878 {
1879         // Save original viewport.
1880         GLuint x = 0, y = 0;
1881
1882         if (width == 0 && height == 0) {
1883                 GLint viewport[4];
1884                 glGetIntegerv(GL_VIEWPORT, viewport);
1885                 x = viewport[0];
1886                 y = viewport[1];
1887                 width = viewport[2];
1888                 height = viewport[3];
1889         }
1890
1891         render(dest_fbo, {}, x, y, width, height);
1892 }
1893
1894 void EffectChain::render_to_texture(const vector<DestinationTexture> &destinations, unsigned width, unsigned height)
1895 {
1896         assert(finalized);
1897         assert(!destinations.empty());
1898
1899         if (!has_dummy_effect) {
1900                 // We don't end in a compute shader, so there's nothing specific for us to do.
1901                 // Create an FBO for this set of textures, and just render to that.
1902                 GLuint texnums[4] = { 0, 0, 0, 0 };
1903                 for (unsigned i = 0; i < destinations.size() && i < 4; ++i) {
1904                         texnums[i] = destinations[i].texnum;
1905                 }
1906                 GLuint dest_fbo = resource_pool->create_fbo(texnums[0], texnums[1], texnums[2], texnums[3]);
1907                 render(dest_fbo, {}, 0, 0, width, height);
1908                 resource_pool->release_fbo(dest_fbo);
1909         } else {
1910                 render((GLuint)-1, destinations, 0, 0, width, height);
1911         }
1912 }
1913
1914 void EffectChain::render(GLuint dest_fbo, const vector<DestinationTexture> &destinations, unsigned x, unsigned y, unsigned width, unsigned height)
1915 {
1916         assert(finalized);
1917         assert(destinations.size() <= 1);
1918
1919         // This needs to be set anew, in case we are coming from a different context
1920         // from when we initialized.
1921         check_error();
1922         glDisable(GL_DITHER);
1923         check_error();
1924
1925         const bool final_srgb = glIsEnabled(GL_FRAMEBUFFER_SRGB);
1926         check_error();
1927         bool current_srgb = final_srgb;
1928
1929         // Basic state.
1930         check_error();
1931         glDisable(GL_BLEND);
1932         check_error();
1933         glDisable(GL_DEPTH_TEST);
1934         check_error();
1935         glDepthMask(GL_FALSE);
1936         check_error();
1937
1938         set<Phase *> generated_mipmaps;
1939
1940         // We keep one texture per output, but only for as long as we actually have any
1941         // phases that need it as an input. (We don't make any effort to reorder phases
1942         // to minimize the number of textures in play, as register allocation can be
1943         // complicated and we rarely have much to gain, since our graphs are typically
1944         // pretty linear.)
1945         map<Phase *, GLuint> output_textures;
1946         map<Phase *, int> ref_counts;
1947         for (Phase *phase : phases) {
1948                 for (Phase *input : phase->inputs) {
1949                         ++ref_counts[input];
1950                 }
1951         }
1952
1953         size_t num_phases = phases.size();
1954         if (destinations.empty()) {
1955                 assert(dest_fbo != (GLuint)-1);
1956         } else {
1957                 assert(has_dummy_effect);
1958                 assert(x == 0);
1959                 assert(y == 0);
1960                 assert(num_phases >= 2);
1961                 assert(!phases.back()->is_compute_shader);
1962                 assert(phases.back()->effects.size() == 1);
1963                 assert(phases.back()->effects[0]->effect->effect_type_id() == "ComputeShaderOutputDisplayEffect");
1964
1965                 // We are rendering to a set of textures, so we can run the compute shader
1966                 // directly and skip the dummy phase.
1967                 --num_phases;
1968         }
1969
1970         for (unsigned phase_num = 0; phase_num < num_phases; ++phase_num) {
1971                 Phase *phase = phases[phase_num];
1972
1973                 if (do_phase_timing) {
1974                         GLuint timer_query_object;
1975                         if (phase->timer_query_objects_free.empty()) {
1976                                 glGenQueries(1, &timer_query_object);
1977                         } else {
1978                                 timer_query_object = phase->timer_query_objects_free.front();
1979                                 phase->timer_query_objects_free.pop_front();
1980                         }
1981                         glBeginQuery(GL_TIME_ELAPSED, timer_query_object);
1982                         phase->timer_query_objects_running.push_back(timer_query_object);
1983                 }
1984                 bool last_phase = (phase_num == num_phases - 1);
1985                 if (phase_num == num_phases - 1) {
1986                         // Last phase goes to the output the user specified.
1987                         if (!phase->is_compute_shader) {
1988                                 glBindFramebuffer(GL_FRAMEBUFFER, dest_fbo);
1989                                 check_error();
1990                                 GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
1991                                 assert(status == GL_FRAMEBUFFER_COMPLETE);
1992                                 glViewport(x, y, width, height);
1993                         }
1994                         if (dither_effect != nullptr) {
1995                                 CHECK(dither_effect->set_int("output_width", width));
1996                                 CHECK(dither_effect->set_int("output_height", height));
1997                         }
1998                 }
1999
2000                 // Enable sRGB rendering for intermediates in case we are
2001                 // rendering to an sRGB format.
2002                 // TODO: Support this for compute shaders.
2003                 bool needs_srgb = last_phase ? final_srgb : true;
2004                 if (needs_srgb && !current_srgb) {
2005                         glEnable(GL_FRAMEBUFFER_SRGB);
2006                         check_error();
2007                         current_srgb = true;
2008                 } else if (!needs_srgb && current_srgb) {
2009                         glDisable(GL_FRAMEBUFFER_SRGB);
2010                         check_error();
2011                         current_srgb = true;
2012                 }
2013
2014                 // Find a texture for this phase.
2015                 inform_input_sizes(phase);
2016                 find_output_size(phase);
2017                 vector<DestinationTexture> phase_destinations;
2018                 if (!last_phase) {
2019                         GLuint tex_num = resource_pool->create_2d_texture(intermediate_format, phase->output_width, phase->output_height);
2020                         output_textures.insert(make_pair(phase, tex_num));
2021                         phase_destinations.push_back(DestinationTexture{ tex_num, intermediate_format });
2022
2023                         // The output texture needs to have valid state to be written to by a compute shader.
2024                         glActiveTexture(GL_TEXTURE0);
2025                         check_error();
2026                         glBindTexture(GL_TEXTURE_2D, tex_num);
2027                         check_error();
2028                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
2029                         check_error();
2030                 } else if (phase->is_compute_shader) {
2031                         assert(!destinations.empty());
2032                         phase_destinations = destinations;
2033                 }
2034
2035                 execute_phase(phase, output_textures, phase_destinations, &generated_mipmaps);
2036                 if (do_phase_timing) {
2037                         glEndQuery(GL_TIME_ELAPSED);
2038                 }
2039
2040                 // Drop any input textures we don't need anymore.
2041                 for (Phase *input : phase->inputs) {
2042                         assert(ref_counts[input] > 0);
2043                         if (--ref_counts[input] == 0) {
2044                                 resource_pool->release_2d_texture(output_textures[input]);
2045                                 output_textures.erase(input);
2046                         }
2047                 }
2048         }
2049
2050         for (const auto &phase_and_texnum : output_textures) {
2051                 resource_pool->release_2d_texture(phase_and_texnum.second);
2052         }
2053
2054         glBindFramebuffer(GL_FRAMEBUFFER, 0);
2055         check_error();
2056         glUseProgram(0);
2057         check_error();
2058
2059         glBindBuffer(GL_ARRAY_BUFFER, 0);
2060         check_error();
2061         glBindVertexArray(0);
2062         check_error();
2063
2064         if (do_phase_timing) {
2065                 // Get back the timer queries.
2066                 for (unsigned phase_num = 0; phase_num < phases.size(); ++phase_num) {
2067                         Phase *phase = phases[phase_num];
2068                         for (auto timer_it = phase->timer_query_objects_running.cbegin();
2069                              timer_it != phase->timer_query_objects_running.cend(); ) {
2070                                 GLint timer_query_object = *timer_it;
2071                                 GLint available;
2072                                 glGetQueryObjectiv(timer_query_object, GL_QUERY_RESULT_AVAILABLE, &available);
2073                                 if (available) {
2074                                         GLuint64 time_elapsed;
2075                                         glGetQueryObjectui64v(timer_query_object, GL_QUERY_RESULT, &time_elapsed);
2076                                         phase->time_elapsed_ns += time_elapsed;
2077                                         ++phase->num_measured_iterations;
2078                                         phase->timer_query_objects_free.push_back(timer_query_object);
2079                                         phase->timer_query_objects_running.erase(timer_it++);
2080                                 } else {
2081                                         ++timer_it;
2082                                 }
2083                         }
2084                 }
2085         }
2086 }
2087
2088 void EffectChain::enable_phase_timing(bool enable)
2089 {
2090         if (enable) {
2091                 assert(movit_timer_queries_supported);
2092         }
2093         this->do_phase_timing = enable;
2094 }
2095
2096 void EffectChain::reset_phase_timing()
2097 {
2098         for (unsigned phase_num = 0; phase_num < phases.size(); ++phase_num) {
2099                 Phase *phase = phases[phase_num];
2100                 phase->time_elapsed_ns = 0;
2101                 phase->num_measured_iterations = 0;
2102         }
2103 }
2104
2105 void EffectChain::print_phase_timing()
2106 {
2107         double total_time_ms = 0.0;
2108         for (unsigned phase_num = 0; phase_num < phases.size(); ++phase_num) {
2109                 Phase *phase = phases[phase_num];
2110                 double avg_time_ms = phase->time_elapsed_ns * 1e-6 / phase->num_measured_iterations;
2111                 printf("Phase %d: %5.1f ms  [", phase_num, avg_time_ms);
2112                 for (unsigned effect_num = 0; effect_num < phase->effects.size(); ++effect_num) {
2113                         if (effect_num != 0) {
2114                                 printf(", ");
2115                         }
2116                         printf("%s", phase->effects[effect_num]->effect->effect_type_id().c_str());
2117                 }
2118                 printf("]\n");
2119                 total_time_ms += avg_time_ms;
2120         }
2121         printf("Total:   %5.1f ms\n", total_time_ms);
2122 }
2123
2124 void EffectChain::execute_phase(Phase *phase,
2125                                 const map<Phase *, GLuint> &output_textures,
2126                                 const std::vector<DestinationTexture> &destinations,
2127                                 set<Phase *> *generated_mipmaps)
2128 {
2129         // Set up RTT inputs for this phase.
2130         for (unsigned sampler = 0; sampler < phase->inputs.size(); ++sampler) {
2131                 glActiveTexture(GL_TEXTURE0 + sampler);
2132                 Phase *input = phase->inputs[sampler];
2133                 input->output_node->bound_sampler_num = sampler;
2134                 const auto it = output_textures.find(input);
2135                 assert(it != output_textures.end());
2136                 glBindTexture(GL_TEXTURE_2D, it->second);
2137                 check_error();
2138                 if (phase->input_needs_mipmaps && generated_mipmaps->count(input) == 0) {
2139                         glGenerateMipmap(GL_TEXTURE_2D);
2140                         check_error();
2141                         generated_mipmaps->insert(input);
2142                 }
2143                 setup_rtt_sampler(sampler, phase->input_needs_mipmaps);
2144                 phase->input_samplers[sampler] = sampler;  // Bind the sampler to the right uniform.
2145         }
2146
2147         GLuint instance_program_num = resource_pool->use_glsl_program(phase->glsl_program_num);
2148         check_error();
2149
2150         // And now the output.
2151         GLuint fbo = 0;
2152         if (phase->is_compute_shader) {
2153                 assert(!destinations.empty());
2154
2155                 // This is currently the only place where we use image units,
2156                 // so we can always start at 0. TODO: Support multiple destinations.
2157                 phase->outbuf_image_unit = 0;
2158                 glBindImageTexture(phase->outbuf_image_unit, destinations[0].texnum, 0, GL_FALSE, 0, GL_WRITE_ONLY, destinations[0].format);
2159                 check_error();
2160                 phase->uniform_output_size[0] = phase->output_width;
2161                 phase->uniform_output_size[1] = phase->output_height;
2162                 phase->inv_output_size.x = 1.0f / phase->output_width;
2163                 phase->inv_output_size.y = 1.0f / phase->output_height;
2164                 phase->output_texcoord_adjust.x = 0.5f / phase->output_width;
2165                 phase->output_texcoord_adjust.y = 0.5f / phase->output_height;
2166         } else if (!destinations.empty()) {
2167                 assert(destinations.size() == 1);
2168                 fbo = resource_pool->create_fbo(destinations[0].texnum);
2169                 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
2170                 glViewport(0, 0, phase->output_width, phase->output_height);
2171         }
2172
2173         // Give the required parameters to all the effects.
2174         unsigned sampler_num = phase->inputs.size();
2175         for (unsigned i = 0; i < phase->effects.size(); ++i) {
2176                 Node *node = phase->effects[i];
2177                 unsigned old_sampler_num = sampler_num;
2178                 node->effect->set_gl_state(instance_program_num, phase->effect_ids[node], &sampler_num);
2179                 check_error();
2180
2181                 if (node->effect->is_single_texture()) {
2182                         assert(sampler_num - old_sampler_num == 1);
2183                         node->bound_sampler_num = old_sampler_num;
2184                 } else {
2185                         node->bound_sampler_num = -1;
2186                 }
2187         }
2188
2189         if (phase->is_compute_shader) {
2190                 unsigned x, y, z;
2191                 phase->compute_shader_node->effect->get_compute_dimensions(phase->output_width, phase->output_height, &x, &y, &z);
2192
2193                 // Uniforms need to come after set_gl_state() _and_ get_compute_dimensions(),
2194                 // since they can be updated from there.
2195                 setup_uniforms(phase);
2196                 glDispatchCompute(x, y, z);
2197                 check_error();
2198                 glMemoryBarrier(GL_TEXTURE_FETCH_BARRIER_BIT | GL_TEXTURE_UPDATE_BARRIER_BIT);
2199                 check_error();
2200         } else {
2201                 // Uniforms need to come after set_gl_state(), since they can be updated
2202                 // from there.
2203                 setup_uniforms(phase);
2204
2205                 // Bind the vertex data.
2206                 GLuint vao = resource_pool->create_vec2_vao(phase->attribute_indexes, vbo);
2207                 glBindVertexArray(vao);
2208
2209                 glDrawArrays(GL_TRIANGLES, 0, 3);
2210                 check_error();
2211
2212                 resource_pool->release_vec2_vao(vao);
2213         }
2214         
2215         for (unsigned i = 0; i < phase->effects.size(); ++i) {
2216                 Node *node = phase->effects[i];
2217                 node->effect->clear_gl_state();
2218         }
2219
2220         resource_pool->unuse_glsl_program(instance_program_num);
2221
2222         if (fbo != 0) {
2223                 resource_pool->release_fbo(fbo);
2224         }
2225 }
2226
2227 void EffectChain::setup_uniforms(Phase *phase)
2228 {
2229         // TODO: Use UBO blocks.
2230         for (size_t i = 0; i < phase->uniforms_image2d.size(); ++i) {
2231                 const Uniform<int> &uniform = phase->uniforms_image2d[i];
2232                 if (uniform.location != -1) {
2233                         glUniform1iv(uniform.location, uniform.num_values, uniform.value);
2234                 }
2235         }
2236         for (size_t i = 0; i < phase->uniforms_sampler2d.size(); ++i) {
2237                 const Uniform<int> &uniform = phase->uniforms_sampler2d[i];
2238                 if (uniform.location != -1) {
2239                         glUniform1iv(uniform.location, uniform.num_values, uniform.value);
2240                 }
2241         }
2242         for (size_t i = 0; i < phase->uniforms_bool.size(); ++i) {
2243                 const Uniform<bool> &uniform = phase->uniforms_bool[i];
2244                 assert(uniform.num_values == 1);
2245                 if (uniform.location != -1) {
2246                         glUniform1i(uniform.location, *uniform.value);
2247                 }
2248         }
2249         for (size_t i = 0; i < phase->uniforms_int.size(); ++i) {
2250                 const Uniform<int> &uniform = phase->uniforms_int[i];
2251                 if (uniform.location != -1) {
2252                         glUniform1iv(uniform.location, uniform.num_values, uniform.value);
2253                 }
2254         }
2255         for (size_t i = 0; i < phase->uniforms_ivec2.size(); ++i) {
2256                 const Uniform<int> &uniform = phase->uniforms_ivec2[i];
2257                 if (uniform.location != -1) {
2258                         glUniform2iv(uniform.location, uniform.num_values, uniform.value);
2259                 }
2260         }
2261         for (size_t i = 0; i < phase->uniforms_float.size(); ++i) {
2262                 const Uniform<float> &uniform = phase->uniforms_float[i];
2263                 if (uniform.location != -1) {
2264                         glUniform1fv(uniform.location, uniform.num_values, uniform.value);
2265                 }
2266         }
2267         for (size_t i = 0; i < phase->uniforms_vec2.size(); ++i) {
2268                 const Uniform<float> &uniform = phase->uniforms_vec2[i];
2269                 if (uniform.location != -1) {
2270                         glUniform2fv(uniform.location, uniform.num_values, uniform.value);
2271                 }
2272         }
2273         for (size_t i = 0; i < phase->uniforms_vec3.size(); ++i) {
2274                 const Uniform<float> &uniform = phase->uniforms_vec3[i];
2275                 if (uniform.location != -1) {
2276                         glUniform3fv(uniform.location, uniform.num_values, uniform.value);
2277                 }
2278         }
2279         for (size_t i = 0; i < phase->uniforms_vec4.size(); ++i) {
2280                 const Uniform<float> &uniform = phase->uniforms_vec4[i];
2281                 if (uniform.location != -1) {
2282                         glUniform4fv(uniform.location, uniform.num_values, uniform.value);
2283                 }
2284         }
2285         for (size_t i = 0; i < phase->uniforms_mat3.size(); ++i) {
2286                 const Uniform<Matrix3d> &uniform = phase->uniforms_mat3[i];
2287                 assert(uniform.num_values == 1);
2288                 if (uniform.location != -1) {
2289                         // Convert to float (GLSL has no double matrices).
2290                         float matrixf[9];
2291                         for (unsigned y = 0; y < 3; ++y) {
2292                                 for (unsigned x = 0; x < 3; ++x) {
2293                                         matrixf[y + x * 3] = (*uniform.value)(y, x);
2294                                 }
2295                         }
2296                         glUniformMatrix3fv(uniform.location, 1, GL_FALSE, matrixf);
2297                 }
2298         }
2299 }
2300
2301 void EffectChain::setup_rtt_sampler(int sampler_num, bool use_mipmaps)
2302 {
2303         glActiveTexture(GL_TEXTURE0 + sampler_num);
2304         check_error();
2305         if (use_mipmaps) {
2306                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
2307                 check_error();
2308         } else {
2309                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
2310                 check_error();
2311         }
2312         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
2313         check_error();
2314         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
2315         check_error();
2316 }
2317
2318 }  // namespace movit