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), use_srgb_texture_format(false), 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 EFFECT_GAMMA_EXPANSION:
38 return new GammaExpansionEffect();
39 case EFFECT_GAMMA_COMPRESSION:
40 return new GammaCompressionEffect();
41 case EFFECT_COLOR_SPACE_CONVERSION:
42 return new ColorSpaceConversionEffect();
43 case EFFECT_LIFT_GAMMA_GAIN:
44 return new LiftGammaGainEffect();
45 case EFFECT_SATURATION:
46 return new SaturationEffect();
51 void EffectChain::normalize_to_linear_gamma()
53 if (current_gamma_curve == GAMMA_sRGB) {
54 // TODO: check if the extension exists
55 use_srgb_texture_format = true;
57 GammaExpansionEffect *gamma_conversion = new GammaExpansionEffect();
58 gamma_conversion->set_int("source_curve", current_gamma_curve);
59 effects.push_back(gamma_conversion);
61 current_gamma_curve = GAMMA_LINEAR;
64 void EffectChain::normalize_to_srgb()
66 assert(current_gamma_curve == GAMMA_LINEAR);
67 ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect();
68 colorspace_conversion->set_int("source_space", current_color_space);
69 colorspace_conversion->set_int("destination_space", COLORSPACE_sRGB);
70 effects.push_back(colorspace_conversion);
71 current_color_space = COLORSPACE_sRGB;
74 Effect *EffectChain::add_effect(EffectId effect_id)
76 Effect *effect = instantiate_effect(effect_id);
78 if (effect->needs_linear_light() && current_gamma_curve != GAMMA_LINEAR) {
79 normalize_to_linear_gamma();
82 if (effect->needs_srgb_primaries() && current_color_space != COLORSPACE_sRGB) {
87 assert(!effect->needs_many_samples());
88 assert(!effect->needs_mipmaps());
90 effects.push_back(effect);
94 // GLSL pre-1.30 doesn't support token pasting. Replace PREFIX(x) with <effect_id>_x.
95 std::string replace_prefix(const std::string &text, const std::string &prefix)
100 while (start < text.size()) {
101 size_t pos = text.find("PREFIX(", start);
102 if (pos == std::string::npos) {
103 output.append(text.substr(start, std::string::npos));
107 output.append(text.substr(start, pos - start));
108 output.append(prefix);
111 pos += strlen("PREFIX(");
113 // Output stuff until we find the matching ), which we then eat.
115 size_t end_arg_pos = pos;
116 while (end_arg_pos < text.size()) {
117 if (text[end_arg_pos] == '(') {
119 } else if (text[end_arg_pos] == ')') {
127 output.append(text.substr(pos, end_arg_pos - pos));
135 void EffectChain::finalize()
137 if (current_color_space != output_format.color_space) {
138 ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect();
139 colorspace_conversion->set_int("source_space", current_color_space);
140 colorspace_conversion->set_int("destination_space", output_format.color_space);
141 effects.push_back(colorspace_conversion);
142 current_color_space = output_format.color_space;
145 if (current_gamma_curve != output_format.gamma_curve) {
146 if (current_gamma_curve != GAMMA_LINEAR) {
147 normalize_to_linear_gamma();
149 assert(current_gamma_curve == GAMMA_LINEAR);
150 GammaCompressionEffect *gamma_conversion = new GammaCompressionEffect();
151 gamma_conversion->set_int("destination_curve", output_format.gamma_curve);
152 effects.push_back(gamma_conversion);
153 current_gamma_curve = output_format.gamma_curve;
156 std::string frag_shader = read_file("header.glsl");
158 for (unsigned i = 0; i < effects.size(); ++i) {
160 sprintf(effect_id, "eff%d", i);
163 frag_shader += std::string("#define FUNCNAME ") + effect_id + "\n";
164 frag_shader += replace_prefix(effects[i]->output_convenience_uniforms(), effect_id);
165 frag_shader += replace_prefix(effects[i]->output_glsl(), effect_id);
166 frag_shader += "#undef PREFIX\n";
167 frag_shader += "#undef FUNCNAME\n";
168 frag_shader += "#undef LAST_INPUT\n";
169 frag_shader += std::string("#define LAST_INPUT ") + effect_id + "\n";
172 frag_shader.append(read_file("footer.glsl"));
173 printf("%s\n", frag_shader.c_str());
175 glsl_program_num = glCreateProgram();
176 GLhandleARB vs_obj = compile_shader(read_file("vs.glsl"), GL_VERTEX_SHADER);
177 GLhandleARB fs_obj = compile_shader(frag_shader, GL_FRAGMENT_SHADER);
178 glAttachShader(glsl_program_num, vs_obj);
180 glAttachShader(glsl_program_num, fs_obj);
182 glLinkProgram(glsl_program_num);
188 void EffectChain::render_to_screen(unsigned char *src)
193 glUseProgram(glsl_program_num);
196 glActiveTexture(GL_TEXTURE0);
197 glBindTexture(GL_TEXTURE_2D, SOURCE_IMAGE);
199 GLenum internal_format = GL_RGBA8;
200 if (use_srgb_texture_format) {
201 internal_format = GL_SRGB8;
204 if (input_format.pixel_format == FORMAT_RGB) {
205 glTexImage2D(GL_TEXTURE_2D, 0, internal_format, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, src);
206 } else if (input_format.pixel_format == FORMAT_RGBA) {
207 glTexImage2D(GL_TEXTURE_2D, 0, internal_format, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, src);
212 glUniform1i(glGetUniformLocation(glsl_program_num, "input_tex"), 0);
214 for (unsigned i = 0; i < effects.size(); ++i) {
216 sprintf(effect_id, "eff%d", i);
217 effects[i]->set_uniforms(glsl_program_num, effect_id);
222 glDisable(GL_DEPTH_TEST);
224 glDepthMask(GL_FALSE);
227 glMatrixMode(GL_PROJECTION);
229 glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0);
231 glMatrixMode(GL_MODELVIEW);
236 glTexCoord2f(0.0f, 1.0f);
237 glVertex2f(0.0f, 0.0f);
239 glTexCoord2f(1.0f, 1.0f);
240 glVertex2f(1.0f, 0.0f);
242 glTexCoord2f(1.0f, 0.0f);
243 glVertex2f(1.0f, 1.0f);
245 glTexCoord2f(0.0f, 0.0f);
246 glVertex2f(0.0f, 1.0f);