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

   1 #define GL_GLEXT_PROTOTYPES 1
   2
   3 #include <stdio.h>
   4 #include <string.h>
   5 #include <assert.h>
   6
   7 #include <GL/gl.h>
   8 #include <GL/glext.h>
   9
  10 #include "util.h"
  11 #include "effect_chain.h"
  12 #include "gamma_expansion_effect.h"
  13 #include "gamma_compression_effect.h"
  14 #include "lift_gamma_gain_effect.h"
  15 #include "colorspace_conversion_effect.h"
  16 #include "sandbox_effect.h"
  17 #include "saturation_effect.h"
  18 #include "mirror_effect.h"
  19 #include "vignette_effect.h"
  20 #include "blur_effect.h"
  21
  22 EffectChain::EffectChain(unsigned width, unsigned height)
  23         : width(width), height(height), use_srgb_texture_format(false), finalized(false) {}
  24
  25 void EffectChain::add_input(const ImageFormat &format)
  26 {
  27         input_format = format;
  28         current_color_space = format.color_space;
  29         current_gamma_curve = format.gamma_curve;
  30 }
  31
  32 void EffectChain::add_output(const ImageFormat &format)
  33 {
  34         output_format = format;
  35 }
  36
  37 Effect *instantiate_effect(EffectId effect)
  38 {
  39         switch (effect) {
  40         case EFFECT_GAMMA_EXPANSION:
  41                 return new GammaExpansionEffect();
  42         case EFFECT_GAMMA_COMPRESSION:
  43                 return new GammaCompressionEffect();
  44         case EFFECT_COLOR_SPACE_CONVERSION:
  45                 return new ColorSpaceConversionEffect();
  46         case EFFECT_SANDBOX:
  47                 return new SandboxEffect();
  48         case EFFECT_LIFT_GAMMA_GAIN:
  49                 return new LiftGammaGainEffect();
  50         case EFFECT_SATURATION:
  51                 return new SaturationEffect();
  52         case EFFECT_MIRROR:
  53                 return new MirrorEffect();
  54         case EFFECT_VIGNETTE:
  55                 return new VignetteEffect();
  56         case EFFECT_BLUR:
  57                 return new BlurEffect();
  58         }
  59         assert(false);
  60 }
  61
  62 void EffectChain::normalize_to_linear_gamma()
  63 {
  64         if (current_gamma_curve == GAMMA_sRGB) {
  65                 // TODO: check if the extension exists
  66                 use_srgb_texture_format = true;
  67         } else {
  68                 GammaExpansionEffect *gamma_conversion = new GammaExpansionEffect();
  69                 gamma_conversion->set_int("source_curve", current_gamma_curve);
  70                 gamma_conversion->add_self_to_effect_chain(&effects);
  71         }
  72         current_gamma_curve = GAMMA_LINEAR;
  73 }
  74
  75 void EffectChain::normalize_to_srgb()
  76 {
  77         assert(current_gamma_curve == GAMMA_LINEAR);
  78         ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect();
  79         colorspace_conversion->set_int("source_space", current_color_space);
  80         colorspace_conversion->set_int("destination_space", COLORSPACE_sRGB);
  81         colorspace_conversion->add_self_to_effect_chain(&effects);
  82         current_color_space = COLORSPACE_sRGB;
  83 }
  84
  85 Effect *EffectChain::add_effect(EffectId effect_id)
  86 {
  87         Effect *effect = instantiate_effect(effect_id);
  88
  89         if (effect->needs_linear_light() && current_gamma_curve != GAMMA_LINEAR) {
  90                 normalize_to_linear_gamma();
  91         }
  92
  93         if (effect->needs_srgb_primaries() && current_color_space != COLORSPACE_sRGB) {
  94                 normalize_to_srgb();
  95         }
  96
  97         effect->add_self_to_effect_chain(&effects);
  98         return effect;
  99 }
 100
 101 // GLSL pre-1.30 doesn't support token pasting. Replace PREFIX(x) with <effect_id>_x.
 102 std::string replace_prefix(const std::string &text, const std::string &prefix)
 103 {
 104         std::string output;
 105         size_t start = 0;
 106
 107         while (start < text.size()) {
 108                 size_t pos = text.find("PREFIX(", start);
 109                 if (pos == std::string::npos) {
 110                         output.append(text.substr(start, std::string::npos));
 111                         break;
 112                 }
 113
 114                 output.append(text.substr(start, pos - start));
 115                 output.append(prefix);
 116                 output.append("_");
 117
 118                 pos += strlen("PREFIX(");
 119
 120                 // Output stuff until we find the matching ), which we then eat.
 121                 int depth = 1;
 122                 size_t end_arg_pos = pos;
 123                 while (end_arg_pos < text.size()) {
 124                         if (text[end_arg_pos] == '(') {
 125                                 ++depth;
 126                         } else if (text[end_arg_pos] == ')') {
 127                                 --depth;
 128                                 if (depth == 0) {
 129                                         break;
 130                                 }
 131                         }
 132                         ++end_arg_pos;
 133                 }
 134                 output.append(text.substr(pos, end_arg_pos - pos));
 135                 ++end_arg_pos;
 136                 assert(depth == 0);
 137                 start = end_arg_pos;
 138         }
 139         return output;
 140 }
 141
 142 EffectChain::Phase EffectChain::compile_glsl_program(unsigned start_index, unsigned end_index)
 143 {
 144         bool input_needs_mipmaps = false;
 145         std::string frag_shader = read_file("header.frag");
 146         for (unsigned i = start_index; i < end_index; ++i) {
 147                 char effect_id[256];
 148                 sprintf(effect_id, "eff%d", i);
 149
 150                 frag_shader += "\n";
 151                 frag_shader += std::string("#define FUNCNAME ") + effect_id + "\n";
 152                 frag_shader += replace_prefix(effects[i]->output_convenience_uniforms(), effect_id);
 153                 frag_shader += replace_prefix(effects[i]->output_fragment_shader(), effect_id);
 154                 frag_shader += "#undef PREFIX\n";
 155                 frag_shader += "#undef FUNCNAME\n";
 156                 frag_shader += "#undef LAST_INPUT\n";
 157                 frag_shader += std::string("#define LAST_INPUT ") + effect_id + "\n";
 158                 frag_shader += "\n";
 159
 160                 input_needs_mipmaps |= effects[i]->needs_mipmaps();
 161         }
 162         frag_shader.append(read_file("footer.frag"));
 163         printf("%s\n", frag_shader.c_str());
 164
 165         GLuint glsl_program_num = glCreateProgram();
 166         GLuint vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
 167         GLuint fs_obj = compile_shader(frag_shader, GL_FRAGMENT_SHADER);
 168         glAttachShader(glsl_program_num, vs_obj);
 169         check_error();
 170         glAttachShader(glsl_program_num, fs_obj);
 171         check_error();
 172         glLinkProgram(glsl_program_num);
 173         check_error();
 174
 175         Phase phase;
 176         phase.glsl_program_num = glsl_program_num;
 177         phase.input_needs_mipmaps = input_needs_mipmaps;
 178         phase.start = start_index;
 179         phase.end = end_index;
 180
 181         return phase;
 182 }
 183
 184 void EffectChain::finalize()
 185 {
 186         // Add normalizers to get the output format right.
 187         if (current_color_space != output_format.color_space) {
 188                 ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect();
 189                 colorspace_conversion->set_int("source_space", current_color_space);
 190                 colorspace_conversion->set_int("destination_space", output_format.color_space);
 191                 effects.push_back(colorspace_conversion);
 192                 current_color_space = output_format.color_space;
 193         }
 194         if (current_gamma_curve != output_format.gamma_curve) {
 195                 if (current_gamma_curve != GAMMA_LINEAR) {
 196                         normalize_to_linear_gamma();
 197                 }
 198                 assert(current_gamma_curve == GAMMA_LINEAR);
 199                 GammaCompressionEffect *gamma_conversion = new GammaCompressionEffect();
 200                 gamma_conversion->set_int("destination_curve", output_format.gamma_curve);
 201                 effects.push_back(gamma_conversion);
 202                 current_gamma_curve = output_format.gamma_curve;
 203         }
 204
 205         // Construct the GLSL programs. We end a program every time we come
 206         // to an effect marked as "needs many samples" (ie. "please let me
 207         // sample directly from a texture, with no arithmetic in-between"),
 208         // and of course at the end.
 209         unsigned start = 0;
 210         for (unsigned i = 0; i < effects.size(); ++i) {
 211                 if (effects[i]->needs_many_samples() && i != start) {
 212                         phases.push_back(compile_glsl_program(start, i));
 213                         start = i;
 214                 }
 215         }
 216         phases.push_back(compile_glsl_program(start, effects.size()));
 217
 218         // If we have more than one phase, we need intermediate render-to-texture.
 219         // Construct an FBO, and then as many textures as we need.
 220         if (phases.size() > 1) {
 221                 glGenFramebuffers(1, &fbo);
 222
 223                 unsigned num_textures = std::max<int>(phases.size() - 1, 2);
 224                 glGenTextures(num_textures, temp_textures);
 225
 226                 for (unsigned i = 0; i < num_textures; ++i) {
 227                         glBindTexture(GL_TEXTURE_2D, temp_textures[i]);
 228                         check_error();
 229                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 230                         check_error();
 231                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 232                         check_error();
 233                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F_ARB, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
 234                         check_error();
 235                 }
 236         }
 237
 238         // Translate the input format to OpenGL's enums.
 239         GLenum internal_format;
 240         if (use_srgb_texture_format) {
 241                 internal_format = GL_SRGB8;
 242         } else {
 243                 internal_format = GL_RGBA8;
 244         }
 245         if (input_format.pixel_format == FORMAT_RGB) {
 246                 format = GL_RGB;
 247                 bytes_per_pixel = 3;
 248         } else if (input_format.pixel_format == FORMAT_RGBA) {
 249                 format = GL_RGBA;
 250                 bytes_per_pixel = 4;
 251         } else if (input_format.pixel_format == FORMAT_BGR) {
 252                 format = GL_BGR;
 253                 bytes_per_pixel = 3;
 254         } else if (input_format.pixel_format == FORMAT_BGRA) {
 255                 format = GL_BGRA;
 256                 bytes_per_pixel = 4;
 257         } else {
 258                 assert(false);
 259         }
 260
 261         // Create PBO to hold the texture holding the input image, and then the texture itself.
 262         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 2);
 263         check_error();
 264         glBufferData(GL_PIXEL_UNPACK_BUFFER_ARB, width * height * bytes_per_pixel, NULL, GL_STREAM_DRAW);
 265         check_error();
 266         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
 267         check_error();
 268
 269         glGenTextures(1, &source_image_num);
 270         check_error();
 271         glBindTexture(GL_TEXTURE_2D, source_image_num);
 272         check_error();
 273         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 274         check_error();
 275         glTexImage2D(GL_TEXTURE_2D, 0, internal_format, width, height, 0, format, GL_UNSIGNED_BYTE, NULL);
 276         check_error();
 277
 278         finalized = true;
 279 }
 280
 281 void EffectChain::render_to_screen(unsigned char *src)
 282 {
 283         assert(finalized);
 284
 285         // Copy the pixel data into the PBO.
 286         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 2);
 287         check_error();
 288         void *mapped_pbo = glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, GL_WRITE_ONLY);
 289         memcpy(mapped_pbo, src, width * height * bytes_per_pixel);
 290         glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB);
 291         check_error();
 292
 293         // Re-upload the texture from the PBO.
 294         glActiveTexture(GL_TEXTURE0);
 295         check_error();
 296         glBindTexture(GL_TEXTURE_2D, source_image_num);
 297         check_error();
 298         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));
 299         check_error();
 300         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 301         check_error();
 302         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 303         check_error();
 304
 305         // Intel/Mesa seems to have a broken glGenerateMipmap() for non-FBO textures, so do it here.
 306         glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, phases[0].input_needs_mipmaps ? GL_TRUE : GL_FALSE);
 307         check_error();
 308
 309         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
 310         check_error();
 311
 312         // Basic state.
 313         glDisable(GL_BLEND);
 314         check_error();
 315         glDisable(GL_DEPTH_TEST);
 316         check_error();
 317         glDepthMask(GL_FALSE);
 318         check_error();
 319
 320         glMatrixMode(GL_PROJECTION);
 321         glLoadIdentity();
 322         glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0);
 323
 324         glMatrixMode(GL_MODELVIEW);
 325         glLoadIdentity();
 326
 327         if (phases.size() > 1) {
 328                 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 329                 check_error();
 330         }
 331
 332         for (unsigned phase = 0; phase < phases.size(); ++phase) {
 333                 // Set up inputs and outputs for this phase.
 334                 glActiveTexture(GL_TEXTURE0);
 335                 if (phase == 0) {
 336                         // First phase reads from the input texture (which is already bound).
 337                 } else {
 338                         glBindTexture(GL_TEXTURE_2D, temp_textures[(phase + 1) % 2]);
 339                         check_error();
 340                 }
 341                 if (phases[phase].input_needs_mipmaps) {
 342                         if (phase != 0) {
 343                                 // For phase 0, it's done further up.
 344                                 glGenerateMipmap(GL_TEXTURE_2D);
 345                                 check_error();
 346                         }
 347                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
 348                         check_error();
 349                 } else {
 350                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 351                         check_error();
 352                 }
 353
 354                 if (phase == phases.size() - 1) {
 355                         // Last phase goes directly to the screen.
 356                         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 357                         check_error();
 358                 } else {
 359                         glFramebufferTexture2D(
 360                                 GL_FRAMEBUFFER,
 361                                 GL_COLOR_ATTACHMENT0,
 362                                 GL_TEXTURE_2D,
 363                                 temp_textures[phase % 2],
 364                                 0);
 365                         check_error();
 366                 }
 367
 368                 // We have baked an upside-down transform into the quad coordinates,
 369                 // since the typical graphics program will have the origin at the upper-left,
 370                 // while OpenGL uses lower-left. In the next ones, however, the origin
 371                 // is all right, and we need to reverse that.
 372                 if (phase == 1) {
 373                         glTranslatef(0.0f, 1.0f, 0.0f);
 374                         glScalef(1.0f, -1.0f, 1.0f);
 375                 }
 376
 377                 // Give the required parameters to all the effects.
 378                 glUseProgram(phases[phase].glsl_program_num);
 379                 check_error();
 380
 381                 glUniform1i(glGetUniformLocation(phases[phase].glsl_program_num, "input_tex"), 0);
 382                 check_error();
 383
 384                 unsigned sampler_num = 1;
 385                 for (unsigned i = phases[phase].start; i < phases[phase].end; ++i) {
 386                         char effect_id[256];
 387                         sprintf(effect_id, "eff%d", i);
 388                         effects[i]->set_uniforms(phases[phase].glsl_program_num, effect_id, &sampler_num);
 389                 }
 390
 391                 // Now draw!
 392                 glBegin(GL_QUADS);
 393
 394                 glTexCoord2f(0.0f, 1.0f);
 395                 glVertex2f(0.0f, 0.0f);
 396
 397                 glTexCoord2f(1.0f, 1.0f);
 398                 glVertex2f(1.0f, 0.0f);
 399
 400                 glTexCoord2f(1.0f, 0.0f);
 401                 glVertex2f(1.0f, 1.0f);
 402
 403                 glTexCoord2f(0.0f, 0.0f);
 404                 glVertex2f(0.0f, 1.0f);
 405
 406                 glEnd();
 407                 check_error();
 408
 409                 // HACK
 410                 glActiveTexture(GL_TEXTURE0);
 411                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
 412                 check_error();
 413                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 1000);
 414                 check_error();
 415         }
 416 }