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 "texture_enum.h"
19 EffectChain::EffectChain(unsigned width, unsigned height)
20 : width(width), height(height), finalized(false) {}
22 void EffectChain::add_input(const ImageFormat &format)
24 input_format = format;
25 current_color_space = format.color_space;
26 current_gamma_curve = format.gamma_curve;
29 void EffectChain::add_output(const ImageFormat &format)
31 output_format = format;
34 Effect *instantiate_effect(EffectId effect)
37 case GAMMA_CONVERSION:
38 return new GammaExpansionEffect();
39 case RGB_PRIMARIES_CONVERSION:
40 return new GammaExpansionEffect();
42 return new LiftGammaGainEffect();
44 return new SaturationEffect();
49 void EffectChain::normalize_to_linear_gamma()
51 GammaExpansionEffect *gamma_conversion = new GammaExpansionEffect();
52 gamma_conversion->set_int("source_curve", current_gamma_curve);
53 effects.push_back(gamma_conversion);
54 current_gamma_curve = GAMMA_LINEAR;
57 void EffectChain::normalize_to_srgb()
59 assert(current_gamma_curve == GAMMA_LINEAR);
60 ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect();
61 colorspace_conversion->set_int("source_space", current_color_space);
62 colorspace_conversion->set_int("destination_space", COLORSPACE_sRGB);
63 effects.push_back(colorspace_conversion);
64 current_color_space = COLORSPACE_sRGB;
67 Effect *EffectChain::add_effect(EffectId effect_id)
69 Effect *effect = instantiate_effect(effect_id);
71 if (effect->needs_linear_light() && current_gamma_curve != GAMMA_LINEAR) {
72 normalize_to_linear_gamma();
75 if (effect->needs_srgb_primaries() && current_color_space != COLORSPACE_sRGB) {
80 assert(!effect->needs_many_samples());
81 assert(!effect->needs_mipmaps());
83 effects.push_back(effect);
87 // GLSL pre-1.30 doesn't support token pasting. Replace PREFIX(x) with <effect_id>_x.
88 std::string replace_prefix(const std::string &text, const std::string &prefix)
93 while (start < text.size()) {
94 size_t pos = text.find("PREFIX(", start);
95 if (pos == std::string::npos) {
96 output.append(text.substr(start, std::string::npos));
100 output.append(text.substr(start, pos - start));
101 output.append(prefix);
104 pos += strlen("PREFIX(");
106 // Output stuff until we find the matching ), which we then eat.
108 size_t end_arg_pos = pos;
109 while (end_arg_pos < text.size()) {
110 if (text[end_arg_pos] == '(') {
112 } else if (text[end_arg_pos] == ')') {
120 output.append(text.substr(pos, end_arg_pos - pos));
128 void EffectChain::finalize()
130 // TODO: If we want a non-sRGB output color space, convert.
132 if (current_gamma_curve != output_format.gamma_curve) {
133 if (current_gamma_curve != GAMMA_LINEAR) {
134 normalize_to_linear_gamma();
136 assert(current_gamma_curve == GAMMA_LINEAR);
137 GammaCompressionEffect *gamma_conversion = new GammaCompressionEffect();
138 gamma_conversion->set_int("destination_curve", output_format.gamma_curve);
139 effects.push_back(gamma_conversion);
140 current_gamma_curve = output_format.gamma_curve;
143 std::string frag_shader = read_file("header.glsl");
145 for (unsigned i = 0; i < effects.size(); ++i) {
147 sprintf(effect_id, "eff%d", i);
150 frag_shader += std::string("#define FUNCNAME ") + effect_id + "\n";
151 frag_shader += replace_prefix(effects[i]->output_convenience_uniforms(), effect_id);
152 frag_shader += replace_prefix(effects[i]->output_glsl(), effect_id);
153 frag_shader += "#undef PREFIX\n";
154 frag_shader += "#undef FUNCNAME\n";
155 frag_shader += "#undef LAST_INPUT\n";
156 frag_shader += std::string("#define LAST_INPUT ") + effect_id + "\n";
159 frag_shader.append(read_file("footer.glsl"));
160 printf("%s\n", frag_shader.c_str());
162 glsl_program_num = glCreateProgram();
163 GLhandleARB vs_obj = compile_shader(read_file("vs.glsl"), GL_VERTEX_SHADER);
164 GLhandleARB fs_obj = compile_shader(frag_shader, GL_FRAGMENT_SHADER);
165 glAttachShader(glsl_program_num, vs_obj);
167 glAttachShader(glsl_program_num, fs_obj);
169 glLinkProgram(glsl_program_num);
175 void EffectChain::render_to_screen(unsigned char *src)
180 glUseProgram(glsl_program_num);
183 glActiveTexture(GL_TEXTURE0);
184 glBindTexture(GL_TEXTURE_2D, SOURCE_IMAGE);
186 // TODO: use sRGB textures if applicable
187 if (input_format.pixel_format == FORMAT_RGB) {
188 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, src);
189 } else if (input_format.pixel_format == FORMAT_RGBA) {
190 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, src);
195 glUniform1i(glGetUniformLocation(glsl_program_num, "input_tex"), 0);
197 for (unsigned i = 0; i < effects.size(); ++i) {
199 sprintf(effect_id, "eff%d", i);
200 effects[i]->set_uniforms(glsl_program_num, effect_id);
205 glDisable(GL_DEPTH_TEST);
207 glDepthMask(GL_FALSE);
210 glMatrixMode(GL_PROJECTION);
212 glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0);
214 glMatrixMode(GL_MODELVIEW);
219 glTexCoord2f(0.0f, 1.0f);
220 glVertex2f(0.0f, 0.0f);
222 glTexCoord2f(1.0f, 1.0f);
223 glVertex2f(1.0f, 0.0f);
225 glTexCoord2f(1.0f, 0.0f);
226 glVertex2f(1.0f, 1.0f);
228 glTexCoord2f(0.0f, 0.0f);
229 glVertex2f(0.0f, 1.0f);