1 #define GL_GLEXT_PROTOTYPES 1
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 "saturation_effect.h"
17 #include "mirror_effect.h"
18 #include "vignette_effect.h"
20 EffectChain::EffectChain(unsigned width, unsigned height)
21 : width(width), height(height), use_srgb_texture_format(false), finalized(false) {}
23 void EffectChain::add_input(const ImageFormat &format)
25 input_format = format;
26 current_color_space = format.color_space;
27 current_gamma_curve = format.gamma_curve;
30 void EffectChain::add_output(const ImageFormat &format)
32 output_format = format;
35 Effect *instantiate_effect(EffectId effect)
38 case EFFECT_GAMMA_EXPANSION:
39 return new GammaExpansionEffect();
40 case EFFECT_GAMMA_COMPRESSION:
41 return new GammaCompressionEffect();
42 case EFFECT_COLOR_SPACE_CONVERSION:
43 return new ColorSpaceConversionEffect();
44 case EFFECT_LIFT_GAMMA_GAIN:
45 return new LiftGammaGainEffect();
46 case EFFECT_SATURATION:
47 return new SaturationEffect();
49 return new MirrorEffect();
51 return new VignetteEffect();
56 void EffectChain::normalize_to_linear_gamma()
58 if (current_gamma_curve == GAMMA_sRGB) {
59 // TODO: check if the extension exists
60 use_srgb_texture_format = true;
62 GammaExpansionEffect *gamma_conversion = new GammaExpansionEffect();
63 gamma_conversion->set_int("source_curve", current_gamma_curve);
64 effects.push_back(gamma_conversion);
66 current_gamma_curve = GAMMA_LINEAR;
69 void EffectChain::normalize_to_srgb()
71 assert(current_gamma_curve == GAMMA_LINEAR);
72 ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect();
73 colorspace_conversion->set_int("source_space", current_color_space);
74 colorspace_conversion->set_int("destination_space", COLORSPACE_sRGB);
75 effects.push_back(colorspace_conversion);
76 current_color_space = COLORSPACE_sRGB;
79 Effect *EffectChain::add_effect(EffectId effect_id)
81 Effect *effect = instantiate_effect(effect_id);
83 if (effect->needs_linear_light() && current_gamma_curve != GAMMA_LINEAR) {
84 normalize_to_linear_gamma();
87 if (effect->needs_srgb_primaries() && current_color_space != COLORSPACE_sRGB) {
92 assert(!effect->needs_many_samples());
93 assert(!effect->needs_mipmaps());
95 effects.push_back(effect);
99 // GLSL pre-1.30 doesn't support token pasting. Replace PREFIX(x) with <effect_id>_x.
100 std::string replace_prefix(const std::string &text, const std::string &prefix)
105 while (start < text.size()) {
106 size_t pos = text.find("PREFIX(", start);
107 if (pos == std::string::npos) {
108 output.append(text.substr(start, std::string::npos));
112 output.append(text.substr(start, pos - start));
113 output.append(prefix);
116 pos += strlen("PREFIX(");
118 // Output stuff until we find the matching ), which we then eat.
120 size_t end_arg_pos = pos;
121 while (end_arg_pos < text.size()) {
122 if (text[end_arg_pos] == '(') {
124 } else if (text[end_arg_pos] == ')') {
132 output.append(text.substr(pos, end_arg_pos - pos));
140 void EffectChain::finalize()
142 if (current_color_space != output_format.color_space) {
143 ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect();
144 colorspace_conversion->set_int("source_space", current_color_space);
145 colorspace_conversion->set_int("destination_space", output_format.color_space);
146 effects.push_back(colorspace_conversion);
147 current_color_space = output_format.color_space;
150 if (current_gamma_curve != output_format.gamma_curve) {
151 if (current_gamma_curve != GAMMA_LINEAR) {
152 normalize_to_linear_gamma();
154 assert(current_gamma_curve == GAMMA_LINEAR);
155 GammaCompressionEffect *gamma_conversion = new GammaCompressionEffect();
156 gamma_conversion->set_int("destination_curve", output_format.gamma_curve);
157 effects.push_back(gamma_conversion);
158 current_gamma_curve = output_format.gamma_curve;
161 std::string frag_shader = read_file("header.frag");
162 for (unsigned i = 0; i < effects.size(); ++i) {
164 sprintf(effect_id, "eff%d", i);
167 frag_shader += std::string("#define FUNCNAME ") + effect_id + "\n";
168 frag_shader += replace_prefix(effects[i]->output_convenience_uniforms(), effect_id);
169 frag_shader += replace_prefix(effects[i]->output_fragment_shader(), effect_id);
170 frag_shader += "#undef PREFIX\n";
171 frag_shader += "#undef FUNCNAME\n";
172 frag_shader += "#undef LAST_INPUT\n";
173 frag_shader += std::string("#define LAST_INPUT ") + effect_id + "\n";
176 frag_shader.append(read_file("footer.frag"));
177 printf("%s\n", frag_shader.c_str());
179 glsl_program_num = glCreateProgram();
180 GLuint vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
181 GLuint fs_obj = compile_shader(frag_shader, GL_FRAGMENT_SHADER);
182 glAttachShader(glsl_program_num, vs_obj);
184 glAttachShader(glsl_program_num, fs_obj);
186 glLinkProgram(glsl_program_num);
189 // Translate the format to OpenGL's enums.
190 GLenum internal_format;
191 if (use_srgb_texture_format) {
192 internal_format = GL_SRGB8;
194 internal_format = GL_RGBA8;
196 if (input_format.pixel_format == FORMAT_RGB) {
199 } else if (input_format.pixel_format == FORMAT_RGBA) {
202 } else if (input_format.pixel_format == FORMAT_BGR) {
205 } else if (input_format.pixel_format == FORMAT_BGRA) {
212 // Create PBO to hold the texture, and then the texture itself.
213 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 2);
215 glBufferData(GL_PIXEL_UNPACK_BUFFER_ARB, width * height * bytes_per_pixel, NULL, GL_STREAM_DRAW);
218 void *mapped_pbo = glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, GL_WRITE_ONLY);
219 memset(mapped_pbo, 0, width * height * bytes_per_pixel);
220 glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB);
222 glGenTextures(1, &source_image_num);
224 glBindTexture(GL_TEXTURE_2D, source_image_num);
226 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
228 glTexImage2D(GL_TEXTURE_2D, 0, internal_format, width, height, 0, format, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));
230 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
236 void EffectChain::render_to_screen(unsigned char *src)
240 // Copy the pixel data into the PBO.
241 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 2);
243 void *mapped_pbo = glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, GL_WRITE_ONLY);
244 memcpy(mapped_pbo, src, width * height * bytes_per_pixel);
245 glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB);
248 // Re-upload the texture from the PBO.
249 glActiveTexture(GL_TEXTURE0);
251 glBindTexture(GL_TEXTURE_2D, source_image_num);
253 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));
255 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
258 glUseProgram(glsl_program_num);
262 glUniform1i(glGetUniformLocation(glsl_program_num, "input_tex"), 0);
264 for (unsigned i = 0; i < effects.size(); ++i) {
266 sprintf(effect_id, "eff%d", i);
267 effects[i]->set_uniforms(glsl_program_num, effect_id);
272 glDisable(GL_DEPTH_TEST);
274 glDepthMask(GL_FALSE);
277 glMatrixMode(GL_PROJECTION);
279 glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0);
281 glMatrixMode(GL_MODELVIEW);
286 glTexCoord2f(0.0f, 1.0f);
287 glVertex2f(0.0f, 0.0f);
289 glTexCoord2f(1.0f, 1.0f);
290 glVertex2f(1.0f, 0.0f);
292 glTexCoord2f(1.0f, 0.0f);
293 glVertex2f(1.0f, 1.0f);
295 glTexCoord2f(0.0f, 0.0f);
296 glVertex2f(0.0f, 1.0f);