git.sesse.net Git - movit/blob - effect_chain.cpp

   1 #define GL_GLEXT_PROTOTYPES 1
   2
   3 #include <GL/glew.h>
   4 #include <assert.h>
   5 #include <locale.h>
   6 #include <math.h>
   7 #include <stddef.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <algorithm>
  12 #include <set>
  13 #include <stack>
  14 #include <vector>
  15
  16 #include "alpha_division_effect.h"
  17 #include "alpha_multiplication_effect.h"
  18 #include "colorspace_conversion_effect.h"
  19 #include "dither_effect.h"
  20 #include "effect.h"
  21 #include "effect_chain.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
  29 using namespace std;
  30
  31 EffectChain::EffectChain(float aspect_nom, float aspect_denom, ResourcePool *resource_pool)
  32         : aspect_nom(aspect_nom),
  33           aspect_denom(aspect_denom),
  34           dither_effect(NULL),
  35           num_dither_bits(0),
  36           finalized(false),
  37           resource_pool(resource_pool) {
  38         if (resource_pool == NULL) {
  39                 this->resource_pool = new ResourcePool();
  40                 owns_resource_pool = true;
  41         } else {
  42                 owns_resource_pool = false;
  43         }
  44 }
  45
  46 EffectChain::~EffectChain()
  47 {
  48         for (unsigned i = 0; i < nodes.size(); ++i) {
  49                 delete nodes[i]->effect;
  50                 delete nodes[i];
  51         }
  52         for (unsigned i = 0; i < phases.size(); ++i) {
  53                 resource_pool->release_glsl_program(phases[i]->glsl_program_num);
  54                 delete phases[i];
  55         }
  56         if (owns_resource_pool) {
  57                 delete resource_pool;
  58         }
  59 }
  60
  61 Input *EffectChain::add_input(Input *input)
  62 {
  63         assert(!finalized);
  64         inputs.push_back(input);
  65         add_node(input);
  66         return input;
  67 }
  68
  69 void EffectChain::add_output(const ImageFormat &format, OutputAlphaFormat alpha_format)
  70 {
  71         assert(!finalized);
  72         output_format = format;
  73         output_alpha_format = alpha_format;
  74 }
  75
  76 Node *EffectChain::add_node(Effect *effect)
  77 {
  78         for (unsigned i = 0; i < nodes.size(); ++i) {
  79                 assert(nodes[i]->effect != effect);
  80         }
  81
  82         Node *node = new Node;
  83         node->effect = effect;
  84         node->disabled = false;
  85         node->output_color_space = COLORSPACE_INVALID;
  86         node->output_gamma_curve = GAMMA_INVALID;
  87         node->output_alpha_type = ALPHA_INVALID;
  88
  89         nodes.push_back(node);
  90         node_map[effect] = node;
  91         effect->inform_added(this);
  92         return node;
  93 }
  94
  95 void EffectChain::connect_nodes(Node *sender, Node *receiver)
  96 {
  97         sender->outgoing_links.push_back(receiver);
  98         receiver->incoming_links.push_back(sender);
  99 }
 100
 101 void EffectChain::replace_receiver(Node *old_receiver, Node *new_receiver)
 102 {
 103         new_receiver->incoming_links = old_receiver->incoming_links;
 104         old_receiver->incoming_links.clear();
 105
 106         for (unsigned i = 0; i < new_receiver->incoming_links.size(); ++i) {
 107                 Node *sender = new_receiver->incoming_links[i];
 108                 for (unsigned j = 0; j < sender->outgoing_links.size(); ++j) {
 109                         if (sender->outgoing_links[j] == old_receiver) {
 110                                 sender->outgoing_links[j] = new_receiver;
 111                         }
 112                 }
 113         }
 114 }
 115
 116 void EffectChain::replace_sender(Node *old_sender, Node *new_sender)
 117 {
 118         new_sender->outgoing_links = old_sender->outgoing_links;
 119         old_sender->outgoing_links.clear();
 120
 121         for (unsigned i = 0; i < new_sender->outgoing_links.size(); ++i) {
 122                 Node *receiver = new_sender->outgoing_links[i];
 123                 for (unsigned j = 0; j < receiver->incoming_links.size(); ++j) {
 124                         if (receiver->incoming_links[j] == old_sender) {
 125                                 receiver->incoming_links[j] = new_sender;
 126                         }
 127                 }
 128         }
 129 }
 130
 131 void EffectChain::insert_node_between(Node *sender, Node *middle, Node *receiver)
 132 {
 133         for (unsigned i = 0; i < sender->outgoing_links.size(); ++i) {
 134                 if (sender->outgoing_links[i] == receiver) {
 135                         sender->outgoing_links[i] = middle;
 136                         middle->incoming_links.push_back(sender);
 137                 }
 138         }
 139         for (unsigned i = 0; i < receiver->incoming_links.size(); ++i) {
 140                 if (receiver->incoming_links[i] == sender) {
 141                         receiver->incoming_links[i] = middle;
 142                         middle->outgoing_links.push_back(receiver);
 143                 }
 144         }
 145
 146         assert(middle->incoming_links.size() == middle->effect->num_inputs());
 147 }
 148
 149 void EffectChain::find_all_nonlinear_inputs(Node *node, vector<Node *> *nonlinear_inputs)
 150 {
 151         if (node->output_gamma_curve == GAMMA_LINEAR &&
 152             node->effect->effect_type_id() != "GammaCompressionEffect") {
 153                 return;
 154         }
 155         if (node->effect->num_inputs() == 0) {
 156                 nonlinear_inputs->push_back(node);
 157         } else {
 158                 assert(node->effect->num_inputs() == node->incoming_links.size());
 159                 for (unsigned i = 0; i < node->incoming_links.size(); ++i) {
 160                         find_all_nonlinear_inputs(node->incoming_links[i], nonlinear_inputs);
 161                 }
 162         }
 163 }
 164
 165 Effect *EffectChain::add_effect(Effect *effect, const vector<Effect *> &inputs)
 166 {
 167         assert(!finalized);
 168         assert(inputs.size() == effect->num_inputs());
 169         Node *node = add_node(effect);
 170         for (unsigned i = 0; i < inputs.size(); ++i) {
 171                 assert(node_map.count(inputs[i]) != 0);
 172                 connect_nodes(node_map[inputs[i]], node);
 173         }
 174         return effect;
 175 }
 176
 177 // GLSL pre-1.30 doesn't support token pasting. Replace PREFIX(x) with <effect_id>_x.
 178 string replace_prefix(const string &text, const string &prefix)
 179 {
 180         string output;
 181         size_t start = 0;
 182
 183         while (start < text.size()) {
 184                 size_t pos = text.find("PREFIX(", start);
 185                 if (pos == string::npos) {
 186                         output.append(text.substr(start, string::npos));
 187                         break;
 188                 }
 189
 190                 output.append(text.substr(start, pos - start));
 191                 output.append(prefix);
 192                 output.append("_");
 193
 194                 pos += strlen("PREFIX(");
 195
 196                 // Output stuff until we find the matching ), which we then eat.
 197                 int depth = 1;
 198                 size_t end_arg_pos = pos;
 199                 while (end_arg_pos < text.size()) {
 200                         if (text[end_arg_pos] == '(') {
 201                                 ++depth;
 202                         } else if (text[end_arg_pos] == ')') {
 203                                 --depth;
 204                                 if (depth == 0) {
 205                                         break;
 206                                 }
 207                         }
 208                         ++end_arg_pos;
 209                 }
 210                 output.append(text.substr(pos, end_arg_pos - pos));
 211                 ++end_arg_pos;
 212                 assert(depth == 0);
 213                 start = end_arg_pos;
 214         }
 215         return output;
 216 }
 217
 218 Phase *EffectChain::compile_glsl_program(
 219         const vector<Node *> &inputs,
 220         const vector<Node *> &effects)
 221 {
 222         Phase *phase = new Phase;
 223         assert(!effects.empty());
 224
 225         // Deduplicate the inputs.
 226         vector<Node *> true_inputs = inputs;
 227         sort(true_inputs.begin(), true_inputs.end());
 228         true_inputs.erase(unique(true_inputs.begin(), true_inputs.end()), true_inputs.end());
 229
 230         bool input_needs_mipmaps = false;
 231         string frag_shader = read_file("header.frag");
 232
 233         // Create functions for all the texture inputs that we need.
 234         for (unsigned i = 0; i < true_inputs.size(); ++i) {
 235                 Node *input = true_inputs[i];
 236                 char effect_id[256];
 237                 sprintf(effect_id, "in%u", i);
 238                 phase->effect_ids.insert(make_pair(input, effect_id));
 239
 240                 frag_shader += string("uniform sampler2D tex_") + effect_id + ";\n";
 241                 frag_shader += string("vec4 ") + effect_id + "(vec2 tc) {\n";
 242                 frag_shader += "\treturn texture2D(tex_" + string(effect_id) + ", tc);\n";
 243                 frag_shader += "}\n";
 244                 frag_shader += "\n";
 245         }
 246
 247         vector<Node *> sorted_effects = topological_sort(effects);
 248
 249         for (unsigned i = 0; i < sorted_effects.size(); ++i) {
 250                 Node *node = sorted_effects[i];
 251                 char effect_id[256];
 252                 sprintf(effect_id, "eff%u", i);
 253                 phase->effect_ids.insert(make_pair(node, effect_id));
 254
 255                 if (node->incoming_links.size() == 1) {
 256                         frag_shader += string("#define INPUT ") + phase->effect_ids[node->incoming_links[0]] + "\n";
 257                 } else {
 258                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 259                                 char buf[256];
 260                                 sprintf(buf, "#define INPUT%d %s\n", j + 1, phase->effect_ids[node->incoming_links[j]].c_str());
 261                                 frag_shader += buf;
 262                         }
 263                 }
 264
 265                 frag_shader += "\n";
 266                 frag_shader += string("#define FUNCNAME ") + effect_id + "\n";
 267                 frag_shader += replace_prefix(node->effect->output_convenience_uniforms(), effect_id);
 268                 frag_shader += replace_prefix(node->effect->output_fragment_shader(), effect_id);
 269                 frag_shader += "#undef PREFIX\n";
 270                 frag_shader += "#undef FUNCNAME\n";
 271                 if (node->incoming_links.size() == 1) {
 272                         frag_shader += "#undef INPUT\n";
 273                 } else {
 274                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 275                                 char buf[256];
 276                                 sprintf(buf, "#undef INPUT%d\n", j + 1);
 277                                 frag_shader += buf;
 278                         }
 279                 }
 280                 frag_shader += "\n";
 281
 282                 input_needs_mipmaps |= node->effect->needs_mipmaps();
 283         }
 284         for (unsigned i = 0; i < sorted_effects.size(); ++i) {
 285                 Node *node = sorted_effects[i];
 286                 if (node->effect->num_inputs() == 0) {
 287                         CHECK(node->effect->set_int("needs_mipmaps", input_needs_mipmaps));
 288                 }
 289         }
 290         frag_shader += string("#define INPUT ") + phase->effect_ids[sorted_effects.back()] + "\n";
 291         frag_shader.append(read_file("footer.frag"));
 292
 293         phase->glsl_program_num = resource_pool->compile_glsl_program(read_file("vs.vert"), frag_shader);
 294         phase->input_needs_mipmaps = input_needs_mipmaps;
 295         phase->inputs = true_inputs;
 296         phase->effects = sorted_effects;
 297
 298         return phase;
 299 }
 300
 301 // Construct GLSL programs, starting at the given effect and following
 302 // the chain from there. We end a program every time we come to an effect
 303 // marked as "needs texture bounce", one that is used by multiple other
 304 // effects, every time an effect wants to change the output size,
 305 // and of course at the end.
 306 //
 307 // We follow a quite simple depth-first search from the output, although
 308 // without any explicit recursion.
 309 void EffectChain::construct_glsl_programs(Node *output)
 310 {
 311         // Which effects have already been completed?
 312         // We need to keep track of it, as an effect with multiple outputs
 313         // could otherwise be calculated multiple times.
 314         set<Node *> completed_effects;
 315
 316         // Effects in the current phase, as well as inputs (outputs from other phases
 317         // that we depend on). Note that since we start iterating from the end,
 318         // the effect list will be in the reverse order.
 319         vector<Node *> this_phase_inputs;
 320         vector<Node *> this_phase_effects;
 321
 322         // Effects that we have yet to calculate, but that we know should
 323         // be in the current phase.
 324         stack<Node *> effects_todo_this_phase;
 325
 326         // Effects that we have yet to calculate, but that come from other phases.
 327         // We delay these until we have this phase done in its entirety,
 328         // at which point we pick any of them and start a new phase from that.
 329         stack<Node *> effects_todo_other_phases;
 330
 331         effects_todo_this_phase.push(output);
 332
 333         for ( ;; ) {  // Termination condition within loop.
 334                 if (!effects_todo_this_phase.empty()) {
 335                         // OK, we have more to do this phase.
 336                         Node *node = effects_todo_this_phase.top();
 337                         effects_todo_this_phase.pop();
 338
 339                         // This should currently only happen for effects that are inputs
 340                         // (either true inputs or phase outputs). We special-case inputs,
 341                         // and then deduplicate phase outputs in compile_glsl_program().
 342                         if (node->effect->num_inputs() == 0) {
 343                                 if (find(this_phase_effects.begin(), this_phase_effects.end(), node) != this_phase_effects.end()) {
 344                                         continue;
 345                                 }
 346                         } else {
 347                                 assert(completed_effects.count(node) == 0);
 348                         }
 349
 350                         this_phase_effects.push_back(node);
 351                         completed_effects.insert(node);
 352
 353                         // Find all the dependencies of this effect, and add them to the stack.
 354                         vector<Node *> deps = node->incoming_links;
 355                         assert(node->effect->num_inputs() == deps.size());
 356                         for (unsigned i = 0; i < deps.size(); ++i) {
 357                                 bool start_new_phase = false;
 358
 359                                 // FIXME: If we sample directly from a texture, we won't need this.
 360                                 if (node->effect->needs_texture_bounce()) {
 361                                         start_new_phase = true;
 362                                 }
 363
 364                                 if (deps[i]->outgoing_links.size() > 1) {
 365                                         if (deps[i]->effect->num_inputs() > 0) {
 366                                                 // More than one effect uses this as the input,
 367                                                 // and it is not a texture itself.
 368                                                 // The easiest thing to do (and probably also the safest
 369                                                 // performance-wise in most cases) is to bounce it to a texture
 370                                                 // and then let the next passes read from that.
 371                                                 start_new_phase = true;
 372                                         } else {
 373                                                 // For textures, we try to be slightly more clever;
 374                                                 // if none of our outputs need a bounce, we don't bounce
 375                                                 // but instead simply use the effect many times.
 376                                                 //
 377                                                 // Strictly speaking, we could bounce it for some outputs
 378                                                 // and use it directly for others, but the processing becomes
 379                                                 // somewhat simpler if the effect is only used in one such way.
 380                                                 for (unsigned j = 0; j < deps[i]->outgoing_links.size(); ++j) {
 381                                                         Node *rdep = deps[i]->outgoing_links[j];
 382                                                         start_new_phase |= rdep->effect->needs_texture_bounce();
 383                                                 }
 384                                         }
 385                                 }
 386
 387                                 if (deps[i]->effect->changes_output_size()) {
 388                                         start_new_phase = true;
 389                                 }
 390
 391                                 if (start_new_phase) {
 392                                         effects_todo_other_phases.push(deps[i]);
 393                                         this_phase_inputs.push_back(deps[i]);
 394                                 } else {
 395                                         effects_todo_this_phase.push(deps[i]);
 396                                 }
 397                         }
 398                         continue;
 399                 }
 400
 401                 // No more effects to do this phase. Take all the ones we have,
 402                 // and create a GLSL program for it.
 403                 if (!this_phase_effects.empty()) {
 404                         reverse(this_phase_effects.begin(), this_phase_effects.end());
 405                         phases.push_back(compile_glsl_program(this_phase_inputs, this_phase_effects));
 406                         this_phase_effects.back()->phase = phases.back();
 407                         this_phase_inputs.clear();
 408                         this_phase_effects.clear();
 409                 }
 410                 assert(this_phase_inputs.empty());
 411                 assert(this_phase_effects.empty());
 412
 413                 // If we have no effects left, exit.
 414                 if (effects_todo_other_phases.empty()) {
 415                         break;
 416                 }
 417
 418                 Node *node = effects_todo_other_phases.top();
 419                 effects_todo_other_phases.pop();
 420
 421                 if (completed_effects.count(node) == 0) {
 422                         // Start a new phase, calculating from this effect.
 423                         effects_todo_this_phase.push(node);
 424                 }
 425         }
 426
 427         // Finally, since the phases are found from the output but must be executed
 428         // from the input(s), reverse them, too.
 429         reverse(phases.begin(), phases.end());
 430 }
 431
 432 void EffectChain::output_dot(const char *filename)
 433 {
 434         if (movit_debug_level != MOVIT_DEBUG_ON) {
 435                 return;
 436         }
 437
 438         FILE *fp = fopen(filename, "w");
 439         if (fp == NULL) {
 440                 perror(filename);
 441                 exit(1);
 442         }
 443
 444         fprintf(fp, "digraph G {\n");
 445         fprintf(fp, "  output [shape=box label=\"(output)\"];\n");
 446         for (unsigned i = 0; i < nodes.size(); ++i) {
 447                 // Find out which phase this event belongs to.
 448                 vector<int> in_phases;
 449                 for (unsigned j = 0; j < phases.size(); ++j) {
 450                         const Phase* p = phases[j];
 451                         if (find(p->effects.begin(), p->effects.end(), nodes[i]) != p->effects.end()) {
 452                                 in_phases.push_back(j);
 453                         }
 454                 }
 455
 456                 if (in_phases.empty()) {
 457                         fprintf(fp, "  n%ld [label=\"%s\"];\n", (long)nodes[i], nodes[i]->effect->effect_type_id().c_str());
 458                 } else if (in_phases.size() == 1) {
 459                         fprintf(fp, "  n%ld [label=\"%s\" style=\"filled\" fillcolor=\"/accent8/%d\"];\n",
 460                                 (long)nodes[i], nodes[i]->effect->effect_type_id().c_str(),
 461                                 (in_phases[0] % 8) + 1);
 462                 } else {
 463                         // If we had new enough Graphviz, style="wedged" would probably be ideal here.
 464                         // But alas.
 465                         fprintf(fp, "  n%ld [label=\"%s [in multiple phases]\" style=\"filled\" fillcolor=\"/accent8/%d\"];\n",
 466                                 (long)nodes[i], nodes[i]->effect->effect_type_id().c_str(),
 467                                 (in_phases[0] % 8) + 1);
 468                 }
 469
 470                 char from_node_id[256];
 471                 snprintf(from_node_id, 256, "n%ld", (long)nodes[i]);
 472
 473                 for (unsigned j = 0; j < nodes[i]->outgoing_links.size(); ++j) {
 474                         char to_node_id[256];
 475                         snprintf(to_node_id, 256, "n%ld", (long)nodes[i]->outgoing_links[j]);
 476
 477                         vector<string> labels = get_labels_for_edge(nodes[i], nodes[i]->outgoing_links[j]);
 478                         output_dot_edge(fp, from_node_id, to_node_id, labels);
 479                 }
 480
 481                 if (nodes[i]->outgoing_links.empty() && !nodes[i]->disabled) {
 482                         // Output node.
 483                         vector<string> labels = get_labels_for_edge(nodes[i], NULL);
 484                         output_dot_edge(fp, from_node_id, "output", labels);
 485                 }
 486         }
 487         fprintf(fp, "}\n");
 488
 489         fclose(fp);
 490 }
 491
 492 vector<string> EffectChain::get_labels_for_edge(const Node *from, const Node *to)
 493 {
 494         vector<string> labels;
 495
 496         if (to != NULL && to->effect->needs_texture_bounce()) {
 497                 labels.push_back("needs_bounce");
 498         }
 499         if (from->effect->changes_output_size()) {
 500                 labels.push_back("resize");
 501         }
 502
 503         switch (from->output_color_space) {
 504         case COLORSPACE_INVALID:
 505                 labels.push_back("spc[invalid]");
 506                 break;
 507         case COLORSPACE_REC_601_525:
 508                 labels.push_back("spc[rec601-525]");
 509                 break;
 510         case COLORSPACE_REC_601_625:
 511                 labels.push_back("spc[rec601-625]");
 512                 break;
 513         default:
 514                 break;
 515         }
 516
 517         switch (from->output_gamma_curve) {
 518         case GAMMA_INVALID:
 519                 labels.push_back("gamma[invalid]");
 520                 break;
 521         case GAMMA_sRGB:
 522                 labels.push_back("gamma[sRGB]");
 523                 break;
 524         case GAMMA_REC_601:  // and GAMMA_REC_709
 525                 labels.push_back("gamma[rec601/709]");
 526                 break;
 527         default:
 528                 break;
 529         }
 530
 531         switch (from->output_alpha_type) {
 532         case ALPHA_INVALID:
 533                 labels.push_back("alpha[invalid]");
 534                 break;
 535         case ALPHA_BLANK:
 536                 labels.push_back("alpha[blank]");
 537                 break;
 538         case ALPHA_POSTMULTIPLIED:
 539                 labels.push_back("alpha[postmult]");
 540                 break;
 541         default:
 542                 break;
 543         }
 544
 545         return labels;
 546 }
 547
 548 void EffectChain::output_dot_edge(FILE *fp,
 549                                   const string &from_node_id,
 550                                   const string &to_node_id,
 551                                   const vector<string> &labels)
 552 {
 553         if (labels.empty()) {
 554                 fprintf(fp, "  %s -> %s;\n", from_node_id.c_str(), to_node_id.c_str());
 555         } else {
 556                 string label = labels[0];
 557                 for (unsigned k = 1; k < labels.size(); ++k) {
 558                         label += ", " + labels[k];
 559                 }
 560                 fprintf(fp, "  %s -> %s [label=\"%s\"];\n", from_node_id.c_str(), to_node_id.c_str(), label.c_str());
 561         }
 562 }
 563
 564 void EffectChain::size_rectangle_to_fit(unsigned width, unsigned height, unsigned *output_width, unsigned *output_height)
 565 {
 566         unsigned scaled_width, scaled_height;
 567
 568         if (float(width) * aspect_denom >= float(height) * aspect_nom) {
 569                 // Same aspect, or W/H > aspect (image is wider than the frame).
 570                 // In either case, keep width, and adjust height.
 571                 scaled_width = width;
 572                 scaled_height = lrintf(width * aspect_denom / aspect_nom);
 573         } else {
 574                 // W/H < aspect (image is taller than the frame), so keep height,
 575                 // and adjust width.
 576                 scaled_width = lrintf(height * aspect_nom / aspect_denom);
 577                 scaled_height = height;
 578         }
 579
 580         // We should be consistently larger or smaller then the existing choice,
 581         // since we have the same aspect.
 582         assert(!(scaled_width < *output_width && scaled_height > *output_height));
 583         assert(!(scaled_height < *output_height && scaled_width > *output_width));
 584
 585         if (scaled_width >= *output_width && scaled_height >= *output_height) {
 586                 *output_width = scaled_width;
 587                 *output_height = scaled_height;
 588         }
 589 }
 590
 591 // Propagate input texture sizes throughout, and inform effects downstream.
 592 // (Like a lot of other code, we depend on effects being in topological order.)
 593 void EffectChain::inform_input_sizes(Phase *phase)
 594 {
 595         // All effects that have a defined size (inputs and RTT inputs)
 596         // get that. Reset all others.
 597         for (unsigned i = 0; i < phase->effects.size(); ++i) {
 598                 Node *node = phase->effects[i];
 599                 if (node->effect->num_inputs() == 0) {
 600                         Input *input = static_cast<Input *>(node->effect);
 601                         node->output_width = input->get_width();
 602                         node->output_height = input->get_height();
 603                         assert(node->output_width != 0);
 604                         assert(node->output_height != 0);
 605                 } else {
 606                         node->output_width = node->output_height = 0;
 607                 }
 608         }
 609         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
 610                 Node *input = phase->inputs[i];
 611                 input->output_width = input->phase->virtual_output_width;
 612                 input->output_height = input->phase->virtual_output_height;
 613                 assert(input->output_width != 0);
 614                 assert(input->output_height != 0);
 615         }
 616
 617         // Now propagate from the inputs towards the end, and inform as we go.
 618         // The rules are simple:
 619         //
 620         //   1. Don't touch effects that already have given sizes (ie., inputs).
 621         //   2. If all of your inputs have the same size, that will be your output size.
 622         //   3. Otherwise, your output size is 0x0.
 623         for (unsigned i = 0; i < phase->effects.size(); ++i) {
 624                 Node *node = phase->effects[i];
 625                 if (node->effect->num_inputs() == 0) {
 626                         continue;
 627                 }
 628                 unsigned this_output_width = 0;
 629                 unsigned this_output_height = 0;
 630                 for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 631                         Node *input = node->incoming_links[j];
 632                         node->effect->inform_input_size(j, input->output_width, input->output_height);
 633                         if (j == 0) {
 634                                 this_output_width = input->output_width;
 635                                 this_output_height = input->output_height;
 636                         } else if (input->output_width != this_output_width || input->output_height != this_output_height) {
 637                                 // Inputs disagree.
 638                                 this_output_width = 0;
 639                                 this_output_height = 0;
 640                         }
 641                 }
 642                 node->output_width = this_output_width;
 643                 node->output_height = this_output_height;
 644         }
 645 }
 646
 647 // Note: You should call inform_input_sizes() before this, as the last effect's
 648 // desired output size might change based on the inputs.
 649 void EffectChain::find_output_size(Phase *phase)
 650 {
 651         Node *output_node = phase->effects.back();
 652
 653         // If the last effect explicitly sets an output size, use that.
 654         if (output_node->effect->changes_output_size()) {
 655                 output_node->effect->get_output_size(&phase->output_width, &phase->output_height,
 656                                                      &phase->virtual_output_width, &phase->virtual_output_height);
 657                 return;
 658         }
 659
 660         // If all effects have the same size, use that.
 661         unsigned output_width = 0, output_height = 0;
 662         bool all_inputs_same_size = true;
 663
 664         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
 665                 Node *input = phase->inputs[i];
 666                 assert(input->phase->output_width != 0);
 667                 assert(input->phase->output_height != 0);
 668                 if (output_width == 0 && output_height == 0) {
 669                         output_width = input->phase->virtual_output_width;
 670                         output_height = input->phase->virtual_output_height;
 671                 } else if (output_width != input->phase->virtual_output_width ||
 672                            output_height != input->phase->virtual_output_height) {
 673                         all_inputs_same_size = false;
 674                 }
 675         }
 676         for (unsigned i = 0; i < phase->effects.size(); ++i) {
 677                 Effect *effect = phase->effects[i]->effect;
 678                 if (effect->num_inputs() != 0) {
 679                         continue;
 680                 }
 681
 682                 Input *input = static_cast<Input *>(effect);
 683                 if (output_width == 0 && output_height == 0) {
 684                         output_width = input->get_width();
 685                         output_height = input->get_height();
 686                 } else if (output_width != input->get_width() ||
 687                            output_height != input->get_height()) {
 688                         all_inputs_same_size = false;
 689                 }
 690         }
 691
 692         if (all_inputs_same_size) {
 693                 assert(output_width != 0);
 694                 assert(output_height != 0);
 695                 phase->virtual_output_width = phase->output_width = output_width;
 696                 phase->virtual_output_height = phase->output_height = output_height;
 697                 return;
 698         }
 699
 700         // If not, fit all the inputs into the current aspect, and select the largest one.
 701         output_width = 0;
 702         output_height = 0;
 703         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
 704                 Node *input = phase->inputs[i];
 705                 assert(input->phase->output_width != 0);
 706                 assert(input->phase->output_height != 0);
 707                 size_rectangle_to_fit(input->phase->output_width, input->phase->output_height, &output_width, &output_height);
 708         }
 709         for (unsigned i = 0; i < phase->effects.size(); ++i) {
 710                 Effect *effect = phase->effects[i]->effect;
 711                 if (effect->num_inputs() != 0) {
 712                         continue;
 713                 }
 714
 715                 Input *input = static_cast<Input *>(effect);
 716                 size_rectangle_to_fit(input->get_width(), input->get_height(), &output_width, &output_height);
 717         }
 718         assert(output_width != 0);
 719         assert(output_height != 0);
 720         phase->virtual_output_width = phase->output_width = output_width;
 721         phase->virtual_output_height = phase->output_height = output_height;
 722 }
 723
 724 void EffectChain::sort_all_nodes_topologically()
 725 {
 726         nodes = topological_sort(nodes);
 727 }
 728
 729 vector<Node *> EffectChain::topological_sort(const vector<Node *> &nodes)
 730 {
 731         set<Node *> nodes_left_to_visit(nodes.begin(), nodes.end());
 732         vector<Node *> sorted_list;
 733         for (unsigned i = 0; i < nodes.size(); ++i) {
 734                 topological_sort_visit_node(nodes[i], &nodes_left_to_visit, &sorted_list);
 735         }
 736         reverse(sorted_list.begin(), sorted_list.end());
 737         return sorted_list;
 738 }
 739
 740 void EffectChain::topological_sort_visit_node(Node *node, set<Node *> *nodes_left_to_visit, vector<Node *> *sorted_list)
 741 {
 742         if (nodes_left_to_visit->count(node) == 0) {
 743                 return;
 744         }
 745         nodes_left_to_visit->erase(node);
 746         for (unsigned i = 0; i < node->outgoing_links.size(); ++i) {
 747                 topological_sort_visit_node(node->outgoing_links[i], nodes_left_to_visit, sorted_list);
 748         }
 749         sorted_list->push_back(node);
 750 }
 751
 752 void EffectChain::find_color_spaces_for_inputs()
 753 {
 754         for (unsigned i = 0; i < nodes.size(); ++i) {
 755                 Node *node = nodes[i];
 756                 if (node->disabled) {
 757                         continue;
 758                 }
 759                 if (node->incoming_links.size() == 0) {
 760                         Input *input = static_cast<Input *>(node->effect);
 761                         node->output_color_space = input->get_color_space();
 762                         node->output_gamma_curve = input->get_gamma_curve();
 763
 764                         Effect::AlphaHandling alpha_handling = input->alpha_handling();
 765                         switch (alpha_handling) {
 766                         case Effect::OUTPUT_BLANK_ALPHA:
 767                                 node->output_alpha_type = ALPHA_BLANK;
 768                                 break;
 769                         case Effect::INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA:
 770                                 node->output_alpha_type = ALPHA_PREMULTIPLIED;
 771                                 break;
 772                         case Effect::OUTPUT_POSTMULTIPLIED_ALPHA:
 773                                 node->output_alpha_type = ALPHA_POSTMULTIPLIED;
 774                                 break;
 775                         case Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK:
 776                         case Effect::DONT_CARE_ALPHA_TYPE:
 777                         default:
 778                                 assert(false);
 779                         }
 780
 781                         if (node->output_alpha_type == ALPHA_PREMULTIPLIED) {
 782                                 assert(node->output_gamma_curve == GAMMA_LINEAR);
 783                         }
 784                 }
 785         }
 786 }
 787
 788 // Propagate gamma and color space information as far as we can in the graph.
 789 // The rules are simple: Anything where all the inputs agree, get that as
 790 // output as well. Anything else keeps having *_INVALID.
 791 void EffectChain::propagate_gamma_and_color_space()
 792 {
 793         // We depend on going through the nodes in order.
 794         sort_all_nodes_topologically();
 795
 796         for (unsigned i = 0; i < nodes.size(); ++i) {
 797                 Node *node = nodes[i];
 798                 if (node->disabled) {
 799                         continue;
 800                 }
 801                 assert(node->incoming_links.size() == node->effect->num_inputs());
 802                 if (node->incoming_links.size() == 0) {
 803                         assert(node->output_color_space != COLORSPACE_INVALID);
 804                         assert(node->output_gamma_curve != GAMMA_INVALID);
 805                         continue;
 806                 }
 807
 808                 Colorspace color_space = node->incoming_links[0]->output_color_space;
 809                 GammaCurve gamma_curve = node->incoming_links[0]->output_gamma_curve;
 810                 for (unsigned j = 1; j < node->incoming_links.size(); ++j) {
 811                         if (node->incoming_links[j]->output_color_space != color_space) {
 812                                 color_space = COLORSPACE_INVALID;
 813                         }
 814                         if (node->incoming_links[j]->output_gamma_curve != gamma_curve) {
 815                                 gamma_curve = GAMMA_INVALID;
 816                         }
 817                 }
 818
 819                 // The conversion effects already have their outputs set correctly,
 820                 // so leave them alone.
 821                 if (node->effect->effect_type_id() != "ColorspaceConversionEffect") {
 822                         node->output_color_space = color_space;
 823                 }
 824                 if (node->effect->effect_type_id() != "GammaCompressionEffect" &&
 825                     node->effect->effect_type_id() != "GammaExpansionEffect") {
 826                         node->output_gamma_curve = gamma_curve;
 827                 }
 828         }
 829 }
 830
 831 // Propagate alpha information as far as we can in the graph.
 832 // Similar to propagate_gamma_and_color_space().
 833 void EffectChain::propagate_alpha()
 834 {
 835         // We depend on going through the nodes in order.
 836         sort_all_nodes_topologically();
 837
 838         for (unsigned i = 0; i < nodes.size(); ++i) {
 839                 Node *node = nodes[i];
 840                 if (node->disabled) {
 841                         continue;
 842                 }
 843                 assert(node->incoming_links.size() == node->effect->num_inputs());
 844                 if (node->incoming_links.size() == 0) {
 845                         assert(node->output_alpha_type != ALPHA_INVALID);
 846                         continue;
 847                 }
 848
 849                 // The alpha multiplication/division effects are special cases.
 850                 if (node->effect->effect_type_id() == "AlphaMultiplicationEffect") {
 851                         assert(node->incoming_links.size() == 1);
 852                         assert(node->incoming_links[0]->output_alpha_type == ALPHA_POSTMULTIPLIED);
 853                         node->output_alpha_type = ALPHA_PREMULTIPLIED;
 854                         continue;
 855                 }
 856                 if (node->effect->effect_type_id() == "AlphaDivisionEffect") {
 857                         assert(node->incoming_links.size() == 1);
 858                         assert(node->incoming_links[0]->output_alpha_type == ALPHA_PREMULTIPLIED);
 859                         node->output_alpha_type = ALPHA_POSTMULTIPLIED;
 860                         continue;
 861                 }
 862
 863                 // GammaCompressionEffect and GammaExpansionEffect are also a special case,
 864                 // because they are the only one that _need_ postmultiplied alpha.
 865                 if (node->effect->effect_type_id() == "GammaCompressionEffect" ||
 866                     node->effect->effect_type_id() == "GammaExpansionEffect") {
 867                         assert(node->incoming_links.size() == 1);
 868                         if (node->incoming_links[0]->output_alpha_type == ALPHA_BLANK) {
 869                                 node->output_alpha_type = ALPHA_BLANK;
 870                         } else if (node->incoming_links[0]->output_alpha_type == ALPHA_POSTMULTIPLIED) {
 871                                 node->output_alpha_type = ALPHA_POSTMULTIPLIED;
 872                         } else {
 873                                 node->output_alpha_type = ALPHA_INVALID;
 874                         }
 875                         continue;
 876                 }
 877
 878                 // Only inputs can have unconditional alpha output (OUTPUT_BLANK_ALPHA
 879                 // or OUTPUT_POSTMULTIPLIED_ALPHA), and they have already been
 880                 // taken care of above. Rationale: Even if you could imagine
 881                 // e.g. an effect that took in an image and set alpha=1.0
 882                 // unconditionally, it wouldn't make any sense to have it as
 883                 // e.g. OUTPUT_BLANK_ALPHA, since it wouldn't know whether it
 884                 // got its input pre- or postmultiplied, so it wouldn't know
 885                 // whether to divide away the old alpha or not.
 886                 Effect::AlphaHandling alpha_handling = node->effect->alpha_handling();
 887                 assert(alpha_handling == Effect::INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA ||
 888                        alpha_handling == Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK ||
 889                        alpha_handling == Effect::DONT_CARE_ALPHA_TYPE);
 890
 891                 // If the node has multiple inputs, check that they are all valid and
 892                 // the same.
 893                 bool any_invalid = false;
 894                 bool any_premultiplied = false;
 895                 bool any_postmultiplied = false;
 896
 897                 for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 898                         switch (node->incoming_links[j]->output_alpha_type) {
 899                         case ALPHA_INVALID:
 900                                 any_invalid = true;
 901                                 break;
 902                         case ALPHA_BLANK:
 903                                 // Blank is good as both pre- and postmultiplied alpha,
 904                                 // so just ignore it.
 905                                 break;
 906                         case ALPHA_PREMULTIPLIED:
 907                                 any_premultiplied = true;
 908                                 break;
 909                         case ALPHA_POSTMULTIPLIED:
 910                                 any_postmultiplied = true;
 911                                 break;
 912                         default:
 913                                 assert(false);
 914                         }
 915                 }
 916
 917                 if (any_invalid) {
 918                         node->output_alpha_type = ALPHA_INVALID;
 919                         continue;
 920                 }
 921
 922                 // Inputs must be of the same type.
 923                 if (any_premultiplied && any_postmultiplied) {
 924                         node->output_alpha_type = ALPHA_INVALID;
 925                         continue;
 926                 }
 927
 928                 if (alpha_handling == Effect::INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA ||
 929                     alpha_handling == Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK) {
 930                         // If the effect has asked for premultiplied alpha, check that it has got it.
 931                         if (any_postmultiplied) {
 932                                 node->output_alpha_type = ALPHA_INVALID;
 933                         } else if (!any_premultiplied &&
 934                                    alpha_handling == Effect::INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK) {
 935                                 // Blank input alpha, and the effect preserves blank alpha.
 936                                 node->output_alpha_type = ALPHA_BLANK;
 937                         } else {
 938                                 node->output_alpha_type = ALPHA_PREMULTIPLIED;
 939                         }
 940                 } else {
 941                         // OK, all inputs are the same, and this effect is not going
 942                         // to change it.
 943                         assert(alpha_handling == Effect::DONT_CARE_ALPHA_TYPE);
 944                         if (any_premultiplied) {
 945                                 node->output_alpha_type = ALPHA_PREMULTIPLIED;
 946                         } else if (any_postmultiplied) {
 947                                 node->output_alpha_type = ALPHA_POSTMULTIPLIED;
 948                         } else {
 949                                 node->output_alpha_type = ALPHA_BLANK;
 950                         }
 951                 }
 952         }
 953 }
 954
 955 bool EffectChain::node_needs_colorspace_fix(Node *node)
 956 {
 957         if (node->disabled) {
 958                 return false;
 959         }
 960         if (node->effect->num_inputs() == 0) {
 961                 return false;
 962         }
 963
 964         // propagate_gamma_and_color_space() has already set our output
 965         // to COLORSPACE_INVALID if the inputs differ, so we can rely on that.
 966         if (node->output_color_space == COLORSPACE_INVALID) {
 967                 return true;
 968         }
 969         return (node->effect->needs_srgb_primaries() && node->output_color_space != COLORSPACE_sRGB);
 970 }
 971
 972 // Fix up color spaces so that there are no COLORSPACE_INVALID nodes left in
 973 // the graph. Our strategy is not always optimal, but quite simple:
 974 // Find an effect that's as early as possible where the inputs are of
 975 // unacceptable colorspaces (that is, either different, or, if the effect only
 976 // wants sRGB, not sRGB.) Add appropriate conversions on all its inputs,
 977 // propagate the information anew, and repeat until there are no more such
 978 // effects.
 979 void EffectChain::fix_internal_color_spaces()
 980 {
 981         unsigned colorspace_propagation_pass = 0;
 982         bool found_any;
 983         do {
 984                 found_any = false;
 985                 for (unsigned i = 0; i < nodes.size(); ++i) {
 986                         Node *node = nodes[i];
 987                         if (!node_needs_colorspace_fix(node)) {
 988                                 continue;
 989                         }
 990
 991                         // Go through each input that is not sRGB, and insert
 992                         // a colorspace conversion after it.
 993                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 994                                 Node *input = node->incoming_links[j];
 995                                 assert(input->output_color_space != COLORSPACE_INVALID);
 996                                 if (input->output_color_space == COLORSPACE_sRGB) {
 997                                         continue;
 998                                 }
 999                                 Node *conversion = add_node(new ColorspaceConversionEffect());
1000                                 CHECK(conversion->effect->set_int("source_space", input->output_color_space));
1001                                 CHECK(conversion->effect->set_int("destination_space", COLORSPACE_sRGB));
1002                                 conversion->output_color_space = COLORSPACE_sRGB;
1003                                 replace_sender(input, conversion);
1004                                 connect_nodes(input, conversion);
1005                         }
1006
1007                         // Re-sort topologically, and propagate the new information.
1008                         propagate_gamma_and_color_space();
1009
1010                         found_any = true;
1011                         break;
1012                 }
1013
1014                 char filename[256];
1015                 sprintf(filename, "step5-colorspacefix-iter%u.dot", ++colorspace_propagation_pass);
1016                 output_dot(filename);
1017                 assert(colorspace_propagation_pass < 100);
1018         } while (found_any);
1019
1020         for (unsigned i = 0; i < nodes.size(); ++i) {
1021                 Node *node = nodes[i];
1022                 if (node->disabled) {
1023                         continue;
1024                 }
1025                 assert(node->output_color_space != COLORSPACE_INVALID);
1026         }
1027 }
1028
1029 bool EffectChain::node_needs_alpha_fix(Node *node)
1030 {
1031         if (node->disabled) {
1032                 return false;
1033         }
1034
1035         // propagate_alpha() has already set our output to ALPHA_INVALID if the
1036         // inputs differ or we are otherwise in mismatch, so we can rely on that.
1037         return (node->output_alpha_type == ALPHA_INVALID);
1038 }
1039
1040 // Fix up alpha so that there are no ALPHA_INVALID nodes left in
1041 // the graph. Similar to fix_internal_color_spaces().
1042 void EffectChain::fix_internal_alpha(unsigned step)
1043 {
1044         unsigned alpha_propagation_pass = 0;
1045         bool found_any;
1046         do {
1047                 found_any = false;
1048                 for (unsigned i = 0; i < nodes.size(); ++i) {
1049                         Node *node = nodes[i];
1050                         if (!node_needs_alpha_fix(node)) {
1051                                 continue;
1052                         }
1053
1054                         // If we need to fix up GammaExpansionEffect, then clearly something
1055                         // is wrong, since the combination of premultiplied alpha and nonlinear inputs
1056                         // is meaningless.
1057                         assert(node->effect->effect_type_id() != "GammaExpansionEffect");
1058
1059                         AlphaType desired_type = ALPHA_PREMULTIPLIED;
1060
1061                         // GammaCompressionEffect is special; it needs postmultiplied alpha.
1062                         if (node->effect->effect_type_id() == "GammaCompressionEffect") {
1063                                 assert(node->incoming_links.size() == 1);
1064                                 assert(node->incoming_links[0]->output_alpha_type == ALPHA_PREMULTIPLIED);
1065                                 desired_type = ALPHA_POSTMULTIPLIED;
1066                         }
1067
1068                         // Go through each input that is not premultiplied alpha, and insert
1069                         // a conversion before it.
1070                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
1071                                 Node *input = node->incoming_links[j];
1072                                 assert(input->output_alpha_type != ALPHA_INVALID);
1073                                 if (input->output_alpha_type == desired_type ||
1074                                     input->output_alpha_type == ALPHA_BLANK) {
1075                                         continue;
1076                                 }
1077                                 Node *conversion;
1078                                 if (desired_type == ALPHA_PREMULTIPLIED) {
1079                                         conversion = add_node(new AlphaMultiplicationEffect());
1080                                 } else {
1081                                         conversion = add_node(new AlphaDivisionEffect());
1082                                 }
1083                                 conversion->output_alpha_type = desired_type;
1084                                 replace_sender(input, conversion);
1085                                 connect_nodes(input, conversion);
1086                         }
1087
1088                         // Re-sort topologically, and propagate the new information.
1089                         propagate_gamma_and_color_space();
1090                         propagate_alpha();
1091
1092                         found_any = true;
1093                         break;
1094                 }
1095
1096                 char filename[256];
1097                 sprintf(filename, "step%u-alphafix-iter%u.dot", step, ++alpha_propagation_pass);
1098                 output_dot(filename);
1099                 assert(alpha_propagation_pass < 100);
1100         } while (found_any);
1101
1102         for (unsigned i = 0; i < nodes.size(); ++i) {
1103                 Node *node = nodes[i];
1104                 if (node->disabled) {
1105                         continue;
1106                 }
1107                 assert(node->output_alpha_type != ALPHA_INVALID);
1108         }
1109 }
1110
1111 // Make so that the output is in the desired color space.
1112 void EffectChain::fix_output_color_space()
1113 {
1114         Node *output = find_output_node();
1115         if (output->output_color_space != output_format.color_space) {
1116                 Node *conversion = add_node(new ColorspaceConversionEffect());
1117                 CHECK(conversion->effect->set_int("source_space", output->output_color_space));
1118                 CHECK(conversion->effect->set_int("destination_space", output_format.color_space));
1119                 conversion->output_color_space = output_format.color_space;
1120                 connect_nodes(output, conversion);
1121                 propagate_alpha();
1122                 propagate_gamma_and_color_space();
1123         }
1124 }
1125
1126 // Make so that the output is in the desired pre-/postmultiplication alpha state.
1127 void EffectChain::fix_output_alpha()
1128 {
1129         Node *output = find_output_node();
1130         assert(output->output_alpha_type != ALPHA_INVALID);
1131         if (output->output_alpha_type == ALPHA_BLANK) {
1132                 // No alpha output, so we don't care.
1133                 return;
1134         }
1135         if (output->output_alpha_type == ALPHA_PREMULTIPLIED &&
1136             output_alpha_format == OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED) {
1137                 Node *conversion = add_node(new AlphaDivisionEffect());
1138                 connect_nodes(output, conversion);
1139                 propagate_alpha();
1140                 propagate_gamma_and_color_space();
1141         }
1142         if (output->output_alpha_type == ALPHA_POSTMULTIPLIED &&
1143             output_alpha_format == OUTPUT_ALPHA_FORMAT_PREMULTIPLIED) {
1144                 Node *conversion = add_node(new AlphaMultiplicationEffect());
1145                 connect_nodes(output, conversion);
1146                 propagate_alpha();
1147                 propagate_gamma_and_color_space();
1148         }
1149 }
1150
1151 bool EffectChain::node_needs_gamma_fix(Node *node)
1152 {
1153         if (node->disabled) {
1154                 return false;
1155         }
1156
1157         // Small hack since the output is not an explicit node:
1158         // If we are the last node and our output is in the wrong
1159         // space compared to EffectChain's output, we need to fix it.
1160         // This will only take us to linear, but fix_output_gamma()
1161         // will come and take us to the desired output gamma
1162         // if it is needed.
1163         //
1164         // This needs to be before everything else, since it could
1165         // even apply to inputs (if they are the only effect).
1166         if (node->outgoing_links.empty() &&
1167             node->output_gamma_curve != output_format.gamma_curve &&
1168             node->output_gamma_curve != GAMMA_LINEAR) {
1169                 return true;
1170         }
1171
1172         if (node->effect->num_inputs() == 0) {
1173                 return false;
1174         }
1175
1176         // propagate_gamma_and_color_space() has already set our output
1177         // to GAMMA_INVALID if the inputs differ, so we can rely on that,
1178         // except for GammaCompressionEffect.
1179         if (node->output_gamma_curve == GAMMA_INVALID) {
1180                 return true;
1181         }
1182         if (node->effect->effect_type_id() == "GammaCompressionEffect") {
1183                 assert(node->incoming_links.size() == 1);
1184                 return node->incoming_links[0]->output_gamma_curve != GAMMA_LINEAR;
1185         }
1186
1187         return (node->effect->needs_linear_light() && node->output_gamma_curve != GAMMA_LINEAR);
1188 }
1189
1190 // Very similar to fix_internal_color_spaces(), but for gamma.
1191 // There is one difference, though; before we start adding conversion nodes,
1192 // we see if we can get anything out of asking the sources to deliver
1193 // linear gamma directly. fix_internal_gamma_by_asking_inputs()
1194 // does that part, while fix_internal_gamma_by_inserting_nodes()
1195 // inserts nodes as needed afterwards.
1196 void EffectChain::fix_internal_gamma_by_asking_inputs(unsigned step)
1197 {
1198         unsigned gamma_propagation_pass = 0;
1199         bool found_any;
1200         do {
1201                 found_any = false;
1202                 for (unsigned i = 0; i < nodes.size(); ++i) {
1203                         Node *node = nodes[i];
1204                         if (!node_needs_gamma_fix(node)) {
1205                                 continue;
1206                         }
1207
1208                         // See if all inputs can give us linear gamma. If not, leave it.
1209                         vector<Node *> nonlinear_inputs;
1210                         find_all_nonlinear_inputs(node, &nonlinear_inputs);
1211                         assert(!nonlinear_inputs.empty());
1212
1213                         bool all_ok = true;
1214                         for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
1215                                 Input *input = static_cast<Input *>(nonlinear_inputs[i]->effect);
1216                                 all_ok &= input->can_output_linear_gamma();
1217                         }
1218
1219                         if (!all_ok) {
1220                                 continue;
1221                         }
1222
1223                         for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
1224                                 CHECK(nonlinear_inputs[i]->effect->set_int("output_linear_gamma", 1));
1225                                 nonlinear_inputs[i]->output_gamma_curve = GAMMA_LINEAR;
1226                         }
1227
1228                         // Re-sort topologically, and propagate the new information.
1229                         propagate_gamma_and_color_space();
1230
1231                         found_any = true;
1232                         break;
1233                 }
1234
1235                 char filename[256];
1236                 sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
1237                 output_dot(filename);
1238                 assert(gamma_propagation_pass < 100);
1239         } while (found_any);
1240 }
1241
1242 void EffectChain::fix_internal_gamma_by_inserting_nodes(unsigned step)
1243 {
1244         unsigned gamma_propagation_pass = 0;
1245         bool found_any;
1246         do {
1247                 found_any = false;
1248                 for (unsigned i = 0; i < nodes.size(); ++i) {
1249                         Node *node = nodes[i];
1250                         if (!node_needs_gamma_fix(node)) {
1251                                 continue;
1252                         }
1253
1254                         // Special case: We could be an input and still be asked to
1255                         // fix our gamma; if so, we should be the only node
1256                         // (as node_needs_gamma_fix() would only return true in
1257                         // for an input in that case). That means we should insert
1258                         // a conversion node _after_ ourselves.
1259                         if (node->incoming_links.empty()) {
1260                                 assert(node->outgoing_links.empty());
1261                                 Node *conversion = add_node(new GammaExpansionEffect());
1262                                 CHECK(conversion->effect->set_int("source_curve", node->output_gamma_curve));
1263                                 conversion->output_gamma_curve = GAMMA_LINEAR;
1264                                 connect_nodes(node, conversion);
1265                         }
1266
1267                         // If not, go through each input that is not linear gamma,
1268                         // and insert a gamma conversion after it.
1269                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
1270                                 Node *input = node->incoming_links[j];
1271                                 assert(input->output_gamma_curve != GAMMA_INVALID);
1272                                 if (input->output_gamma_curve == GAMMA_LINEAR) {
1273                                         continue;
1274                                 }
1275                                 Node *conversion = add_node(new GammaExpansionEffect());
1276                                 CHECK(conversion->effect->set_int("source_curve", input->output_gamma_curve));
1277                                 conversion->output_gamma_curve = GAMMA_LINEAR;
1278                                 replace_sender(input, conversion);
1279                                 connect_nodes(input, conversion);
1280                         }
1281
1282                         // Re-sort topologically, and propagate the new information.
1283                         propagate_alpha();
1284                         propagate_gamma_and_color_space();
1285
1286                         found_any = true;
1287                         break;
1288                 }
1289
1290                 char filename[256];
1291                 sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
1292                 output_dot(filename);
1293                 assert(gamma_propagation_pass < 100);
1294         } while (found_any);
1295
1296         for (unsigned i = 0; i < nodes.size(); ++i) {
1297                 Node *node = nodes[i];
1298                 if (node->disabled) {
1299                         continue;
1300                 }
1301                 assert(node->output_gamma_curve != GAMMA_INVALID);
1302         }
1303 }
1304
1305 // Make so that the output is in the desired gamma.
1306 // Note that this assumes linear input gamma, so it might create the need
1307 // for another pass of fix_internal_gamma().
1308 void EffectChain::fix_output_gamma()
1309 {
1310         Node *output = find_output_node();
1311         if (output->output_gamma_curve != output_format.gamma_curve) {
1312                 Node *conversion = add_node(new GammaCompressionEffect());
1313                 CHECK(conversion->effect->set_int("destination_curve", output_format.gamma_curve));
1314                 conversion->output_gamma_curve = output_format.gamma_curve;
1315                 connect_nodes(output, conversion);
1316         }
1317 }
1318
1319 // If the user has requested dither, add a DitherEffect right at the end
1320 // (after GammaCompressionEffect etc.). This needs to be done after everything else,
1321 // since dither is about the only effect that can _not_ be done in linear space.
1322 void EffectChain::add_dither_if_needed()
1323 {
1324         if (num_dither_bits == 0) {
1325                 return;
1326         }
1327         Node *output = find_output_node();
1328         Node *dither = add_node(new DitherEffect());
1329         CHECK(dither->effect->set_int("num_bits", num_dither_bits));
1330         connect_nodes(output, dither);
1331
1332         dither_effect = dither->effect;
1333 }
1334
1335 // Find the output node. This is, simply, one that has no outgoing links.
1336 // If there are multiple ones, the graph is malformed (we do not support
1337 // multiple outputs right now).
1338 Node *EffectChain::find_output_node()
1339 {
1340         vector<Node *> output_nodes;
1341         for (unsigned i = 0; i < nodes.size(); ++i) {
1342                 Node *node = nodes[i];
1343                 if (node->disabled) {
1344                         continue;
1345                 }
1346                 if (node->outgoing_links.empty()) {
1347                         output_nodes.push_back(node);
1348                 }
1349         }
1350         assert(output_nodes.size() == 1);
1351         return output_nodes[0];
1352 }
1353
1354 void EffectChain::finalize()
1355 {
1356         // Save the current locale, and set it to C, so that we can output decimal
1357         // numbers with printf and be sure to get them in the format mandated by GLSL.
1358         char *saved_locale = setlocale(LC_NUMERIC, "C");
1359
1360         // Output the graph as it is before we do any conversions on it.
1361         output_dot("step0-start.dot");
1362
1363         // Give each effect in turn a chance to rewrite its own part of the graph.
1364         // Note that if more effects are added as part of this, they will be
1365         // picked up as part of the same for loop, since they are added at the end.
1366         for (unsigned i = 0; i < nodes.size(); ++i) {
1367                 nodes[i]->effect->rewrite_graph(this, nodes[i]);
1368         }
1369         output_dot("step1-rewritten.dot");
1370
1371         find_color_spaces_for_inputs();
1372         output_dot("step2-input-colorspace.dot");
1373
1374         propagate_alpha();
1375         output_dot("step3-propagated-alpha.dot");
1376
1377         propagate_gamma_and_color_space();
1378         output_dot("step4-propagated-all.dot");
1379
1380         fix_internal_color_spaces();
1381         fix_internal_alpha(6);
1382         fix_output_color_space();
1383         output_dot("step7-output-colorspacefix.dot");
1384         fix_output_alpha();
1385         output_dot("step8-output-alphafix.dot");
1386
1387         // Note that we need to fix gamma after colorspace conversion,
1388         // because colorspace conversions might create needs for gamma conversions.
1389         // Also, we need to run an extra pass of fix_internal_gamma() after
1390         // fixing the output gamma, as we only have conversions to/from linear,
1391         // and fix_internal_alpha() since GammaCompressionEffect needs
1392         // postmultiplied input.
1393         fix_internal_gamma_by_asking_inputs(9);
1394         fix_internal_gamma_by_inserting_nodes(10);
1395         fix_output_gamma();
1396         output_dot("step11-output-gammafix.dot");
1397         propagate_alpha();
1398         output_dot("step12-output-alpha-propagated.dot");
1399         fix_internal_alpha(13);
1400         output_dot("step14-output-alpha-fixed.dot");
1401         fix_internal_gamma_by_asking_inputs(15);
1402         fix_internal_gamma_by_inserting_nodes(16);
1403
1404         output_dot("step17-before-dither.dot");
1405
1406         add_dither_if_needed();
1407
1408         output_dot("step18-final.dot");
1409
1410         // Construct all needed GLSL programs, starting at the output.
1411         construct_glsl_programs(find_output_node());
1412
1413         output_dot("step19-split-to-phases.dot");
1414
1415         for (unsigned i = 0; i < inputs.size(); ++i) {
1416                 inputs[i]->finalize();
1417         }
1418
1419         assert(phases[0]->inputs.empty());
1420
1421         finalized = true;
1422         setlocale(LC_NUMERIC, saved_locale);
1423 }
1424
1425 void EffectChain::render_to_fbo(GLuint dest_fbo, unsigned width, unsigned height)
1426 {
1427         assert(finalized);
1428
1429         // Save original viewport.
1430         GLuint x = 0, y = 0;
1431         GLuint fbo = 0;
1432
1433         if (width == 0 && height == 0) {
1434                 GLint viewport[4];
1435                 glGetIntegerv(GL_VIEWPORT, viewport);
1436                 x = viewport[0];
1437                 y = viewport[1];
1438                 width = viewport[2];
1439                 height = viewport[3];
1440         }
1441
1442         // Basic state.
1443         glDisable(GL_BLEND);
1444         check_error();
1445         glDisable(GL_DEPTH_TEST);
1446         check_error();
1447         glDepthMask(GL_FALSE);
1448         check_error();
1449
1450         glMatrixMode(GL_PROJECTION);
1451         glLoadIdentity();
1452         glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0);
1453
1454         glMatrixMode(GL_MODELVIEW);
1455         glLoadIdentity();
1456
1457         if (phases.size() > 1) {
1458                 glGenFramebuffers(1, &fbo);
1459                 check_error();
1460                 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
1461                 check_error();
1462         }
1463
1464         set<Node *> generated_mipmaps;
1465
1466         // We choose the simplest option of having one texture per output,
1467         // since otherwise this turns into an (albeit simple) register allocation problem.
1468         map<Phase *, GLuint> output_textures;
1469
1470         for (unsigned phase = 0; phase < phases.size(); ++phase) {
1471                 // Find a texture for this phase.
1472                 inform_input_sizes(phases[phase]);
1473                 if (phase != phases.size() - 1) {
1474                         find_output_size(phases[phase]);
1475
1476                         GLuint tex_num = resource_pool->create_2d_texture(GL_RGBA16F_ARB, phases[phase]->output_width, phases[phase]->output_height);
1477                         output_textures.insert(make_pair(phases[phase], tex_num));
1478                 }
1479
1480                 glUseProgram(phases[phase]->glsl_program_num);
1481                 check_error();
1482
1483                 // Set up RTT inputs for this phase.
1484                 for (unsigned sampler = 0; sampler < phases[phase]->inputs.size(); ++sampler) {
1485                         glActiveTexture(GL_TEXTURE0 + sampler);
1486                         Node *input = phases[phase]->inputs[sampler];
1487                         glBindTexture(GL_TEXTURE_2D, output_textures[input->phase]);
1488                         check_error();
1489                         if (phases[phase]->input_needs_mipmaps) {
1490                                 if (generated_mipmaps.count(input) == 0) {
1491                                         glGenerateMipmap(GL_TEXTURE_2D);
1492                                         check_error();
1493                                         generated_mipmaps.insert(input);
1494                                 }
1495                                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
1496                                 check_error();
1497                         } else {
1498                                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1499                                 check_error();
1500                         }
1501                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1502                         check_error();
1503                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1504                         check_error();
1505
1506                         string texture_name = string("tex_") + phases[phase]->effect_ids[input];
1507                         glUniform1i(glGetUniformLocation(phases[phase]->glsl_program_num, texture_name.c_str()), sampler);
1508                         check_error();
1509                 }
1510
1511                 // And now the output.
1512                 if (phase == phases.size() - 1) {
1513                         // Last phase goes to the output the user specified.
1514                         glBindFramebuffer(GL_FRAMEBUFFER, dest_fbo);
1515                         check_error();
1516                         GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
1517                         assert(status == GL_FRAMEBUFFER_COMPLETE);
1518                         glViewport(x, y, width, height);
1519                         if (dither_effect != NULL) {
1520                                 CHECK(dither_effect->set_int("output_width", width));
1521                                 CHECK(dither_effect->set_int("output_height", height));
1522                         }
1523                 } else {
1524                         glFramebufferTexture2D(
1525                                 GL_FRAMEBUFFER,
1526                                 GL_COLOR_ATTACHMENT0,
1527                                 GL_TEXTURE_2D,
1528                                 output_textures[phases[phase]],
1529                                 0);
1530                         check_error();
1531                         GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
1532                         assert(status == GL_FRAMEBUFFER_COMPLETE);
1533                         glViewport(0, 0, phases[phase]->output_width, phases[phase]->output_height);
1534                 }
1535
1536                 // Give the required parameters to all the effects.
1537                 unsigned sampler_num = phases[phase]->inputs.size();
1538                 for (unsigned i = 0; i < phases[phase]->effects.size(); ++i) {
1539                         Node *node = phases[phase]->effects[i];
1540                         node->effect->set_gl_state(phases[phase]->glsl_program_num, phases[phase]->effect_ids[node], &sampler_num);
1541                         check_error();
1542                 }
1543
1544                 // Now draw!
1545                 glBegin(GL_QUADS);
1546
1547                 glTexCoord2f(0.0f, 0.0f);
1548                 glVertex2f(0.0f, 0.0f);
1549
1550                 glTexCoord2f(1.0f, 0.0f);
1551                 glVertex2f(1.0f, 0.0f);
1552
1553                 glTexCoord2f(1.0f, 1.0f);
1554                 glVertex2f(1.0f, 1.0f);
1555
1556                 glTexCoord2f(0.0f, 1.0f);
1557                 glVertex2f(0.0f, 1.0f);
1558
1559                 glEnd();
1560                 check_error();
1561
1562                 for (unsigned i = 0; i < phases[phase]->effects.size(); ++i) {
1563                         Node *node = phases[phase]->effects[i];
1564                         node->effect->clear_gl_state();
1565                 }
1566         }
1567
1568         for (map<Phase *, GLuint>::const_iterator texture_it = output_textures.begin();
1569              texture_it != output_textures.end();
1570              ++texture_it) {
1571                 resource_pool->release_2d_texture(texture_it->second);
1572         }
1573
1574         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1575         check_error();
1576
1577         if (fbo != 0) {
1578                 glDeleteFramebuffers(1, &fbo);
1579                 check_error();
1580         }
1581 }