From: Steinar H. Gunderson Date: Tue, 2 Oct 2012 22:20:05 +0000 (+0200) Subject: Support multiple render phases (with FBOs and all), and make a sample blur effect... X-Git-Tag: 1.0~417 X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;h=b5e3174594efe9a920621a68d3b28f5e44676d03;hp=3915264bd8fde4d550e47c10a67a2741625b9033;p=movit Support multiple render phases (with FBOs and all), and make a sample blur effect that uses it. --- diff --git a/Makefile b/Makefile index 917d2bd..b2cb059 100644 --- a/Makefile +++ b/Makefile @@ -3,7 +3,7 @@ CXX=g++ CXXFLAGS=-Wall -g LDFLAGS=-lSDL -lSDL_image -lGL OBJS=main.o util.o widgets.o effect.o effect_chain.o -OBJS += lift_gamma_gain_effect.o gamma_expansion_effect.o gamma_compression_effect.o colorspace_conversion_effect.o saturation_effect.o vignette_effect.o mirror_effect.o +OBJS += lift_gamma_gain_effect.o gamma_expansion_effect.o gamma_compression_effect.o colorspace_conversion_effect.o saturation_effect.o vignette_effect.o mirror_effect.o blur_effect.o test: $(OBJS) $(CXX) -o test $(OBJS) $(LDFLAGS) diff --git a/blur_effect.cpp b/blur_effect.cpp new file mode 100644 index 0000000..e945295 --- /dev/null +++ b/blur_effect.cpp @@ -0,0 +1,24 @@ +#define GL_GLEXT_PROTOTYPES 1 + +#include +#include +#include + +#include "blur_effect.h" +#include "util.h" + +BlurEffect::BlurEffect() + : radius(0.3f) +{ + register_float("radius", (float *)&radius); +} + +std::string BlurEffect::output_fragment_shader() +{ + return read_file("blur_effect.frag"); +} + +void BlurEffect::set_uniforms(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num) +{ + Effect::set_uniforms(glsl_program_num, prefix, sampler_num); +} diff --git a/blur_effect.frag b/blur_effect.frag new file mode 100644 index 0000000..bfa1d16 --- /dev/null +++ b/blur_effect.frag @@ -0,0 +1,17 @@ +// A simple, very stupid horizontal blur. Will be fixed soonish. + +vec4 FUNCNAME(vec2 tc) { + vec4 x = LAST_INPUT(tc); + return + vec4(0.1) * LAST_INPUT(tc + vec2(-0.010f, 0.0)) + + vec4(0.1) * LAST_INPUT(tc + vec2(-0.008f, 0.0)) + + vec4(0.1) * LAST_INPUT(tc + vec2(-0.006f, 0.0)) + + vec4(0.1) * LAST_INPUT(tc + vec2(-0.004f, 0.0)) + + vec4(0.2) * LAST_INPUT(tc + vec2(-0.002f, 0.0)) + + vec4(0.3) * LAST_INPUT(tc + vec2(-0.000f, 0.0)) + + vec4(0.2) * LAST_INPUT(tc + vec2( 0.002f, 0.0)) + + vec4(0.1) * LAST_INPUT(tc + vec2( 0.004f, 0.0)) + + vec4(0.1) * LAST_INPUT(tc + vec2( 0.006f, 0.0)) + + vec4(0.1) * LAST_INPUT(tc + vec2( 0.008f, 0.0)) + + vec4(0.1) * LAST_INPUT(tc + vec2( 0.010f, 0.0)); +} diff --git a/blur_effect.h b/blur_effect.h new file mode 100644 index 0000000..0657136 --- /dev/null +++ b/blur_effect.h @@ -0,0 +1,20 @@ +#ifndef _BLUR_EFFECT_H +#define _BLUR_EFFECT_H 1 + +#include "effect.h" + +class BlurEffect : public Effect { +public: + BlurEffect(); + std::string output_fragment_shader(); + + virtual bool needs_many_samples() const { return true; } + virtual bool needs_mipmaps() const { return true; } + + void set_uniforms(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num); + +private: + float radius; +}; + +#endif // !defined(_BLUR_EFFECT_H) diff --git a/effect_chain.cpp b/effect_chain.cpp index 9ff5fd8..899c6a3 100644 --- a/effect_chain.cpp +++ b/effect_chain.cpp @@ -16,6 +16,7 @@ #include "saturation_effect.h" #include "mirror_effect.h" #include "vignette_effect.h" +#include "blur_effect.h" EffectChain::EffectChain(unsigned width, unsigned height) : width(width), height(height), use_srgb_texture_format(false), finalized(false) {} @@ -49,6 +50,8 @@ Effect *instantiate_effect(EffectId effect) return new MirrorEffect(); case EFFECT_VIGNETTE: return new VignetteEffect(); + case EFFECT_BLUR: + return new BlurEffect(); } assert(false); } @@ -88,10 +91,6 @@ Effect *EffectChain::add_effect(EffectId effect_id) normalize_to_srgb(); } - // not handled yet - assert(!effect->needs_many_samples()); - assert(!effect->needs_mipmaps()); - effects.push_back(effect); return effect; } @@ -137,29 +136,11 @@ std::string replace_prefix(const std::string &text, const std::string &prefix) return output; } -void EffectChain::finalize() +EffectChain::Phase EffectChain::compile_glsl_program(unsigned start_index, unsigned end_index) { - if (current_color_space != output_format.color_space) { - ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect(); - colorspace_conversion->set_int("source_space", current_color_space); - colorspace_conversion->set_int("destination_space", output_format.color_space); - effects.push_back(colorspace_conversion); - current_color_space = output_format.color_space; - } - - if (current_gamma_curve != output_format.gamma_curve) { - if (current_gamma_curve != GAMMA_LINEAR) { - normalize_to_linear_gamma(); - } - assert(current_gamma_curve == GAMMA_LINEAR); - GammaCompressionEffect *gamma_conversion = new GammaCompressionEffect(); - gamma_conversion->set_int("destination_curve", output_format.gamma_curve); - effects.push_back(gamma_conversion); - current_gamma_curve = output_format.gamma_curve; - } - + bool input_needs_mipmaps = false; std::string frag_shader = read_file("header.frag"); - for (unsigned i = 0; i < effects.size(); ++i) { + for (unsigned i = start_index; i < end_index; ++i) { char effect_id[256]; sprintf(effect_id, "eff%d", i); @@ -172,11 +153,13 @@ void EffectChain::finalize() frag_shader += "#undef LAST_INPUT\n"; frag_shader += std::string("#define LAST_INPUT ") + effect_id + "\n"; frag_shader += "\n"; + + input_needs_mipmaps |= effects[i]->needs_mipmaps(); } frag_shader.append(read_file("footer.frag")); printf("%s\n", frag_shader.c_str()); - glsl_program_num = glCreateProgram(); + GLuint glsl_program_num = glCreateProgram(); GLuint vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER); GLuint fs_obj = compile_shader(frag_shader, GL_FRAGMENT_SHADER); glAttachShader(glsl_program_num, vs_obj); @@ -186,7 +169,68 @@ void EffectChain::finalize() glLinkProgram(glsl_program_num); check_error(); - // Translate the format to OpenGL's enums. + Phase phase; + phase.glsl_program_num = glsl_program_num; + phase.input_needs_mipmaps = input_needs_mipmaps; + phase.start = start_index; + phase.end = end_index; + + return phase; +} + +void EffectChain::finalize() +{ + // Add normalizers to get the output format right. + if (current_color_space != output_format.color_space) { + ColorSpaceConversionEffect *colorspace_conversion = new ColorSpaceConversionEffect(); + colorspace_conversion->set_int("source_space", current_color_space); + colorspace_conversion->set_int("destination_space", output_format.color_space); + effects.push_back(colorspace_conversion); + current_color_space = output_format.color_space; + } + if (current_gamma_curve != output_format.gamma_curve) { + if (current_gamma_curve != GAMMA_LINEAR) { + normalize_to_linear_gamma(); + } + assert(current_gamma_curve == GAMMA_LINEAR); + GammaCompressionEffect *gamma_conversion = new GammaCompressionEffect(); + gamma_conversion->set_int("destination_curve", output_format.gamma_curve); + effects.push_back(gamma_conversion); + current_gamma_curve = output_format.gamma_curve; + } + + // Construct the GLSL programs. We end a program every time we come + // to an effect marked as "needs many samples" (ie. "please let me + // sample directly from a texture, with no arithmetic in-between"), + // and of course at the end. + unsigned start = 0; + for (unsigned i = 0; i < effects.size(); ++i) { + if (effects[i]->needs_many_samples() && i != start) { + phases.push_back(compile_glsl_program(start, i)); + start = i; + } + } + phases.push_back(compile_glsl_program(start, effects.size())); + + // If we have more than one phase, we need intermediate render-to-texture. + // Construct an FBO, and then as many textures as we need. + if (phases.size() > 1) { + glGenFramebuffers(1, &fbo); + + unsigned num_textures = std::max(phases.size() - 1, 2); + glGenTextures(num_textures, temp_textures); + + unsigned char *empty = new unsigned char[width * height * 4]; + for (unsigned i = 0; i < num_textures; ++i) { + glBindTexture(GL_TEXTURE_2D, temp_textures[i]); + check_error(); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F_ARB, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, empty); + check_error(); + } + delete[] empty; + } + + // Translate the input format to OpenGL's enums. GLenum internal_format; if (use_srgb_texture_format) { internal_format = GL_SRGB8; @@ -209,7 +253,7 @@ void EffectChain::finalize() assert(false); } - // Create PBO to hold the texture, and then the texture itself. + // Create PBO to hold the texture holding the input image, and then the texture itself. glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 2); check_error(); glBufferData(GL_PIXEL_UNPACK_BUFFER_ARB, width * height * bytes_per_pixel, NULL, GL_STREAM_DRAW); @@ -252,22 +296,14 @@ void EffectChain::render_to_screen(unsigned char *src) check_error(); glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0)); check_error(); - glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); check_error(); - - glUseProgram(glsl_program_num); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); check_error(); - + glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0); check_error(); - glUniform1i(glGetUniformLocation(glsl_program_num, "input_tex"), 0); - - unsigned sampler_num = 1; - for (unsigned i = 0; i < effects.size(); ++i) { - char effect_id[256]; - sprintf(effect_id, "eff%d", i); - effects[i]->set_uniforms(glsl_program_num, effect_id, &sampler_num); - } + // Basic state. glDisable(GL_BLEND); check_error(); glDisable(GL_DEPTH_TEST); @@ -282,20 +318,81 @@ void EffectChain::render_to_screen(unsigned char *src) glMatrixMode(GL_MODELVIEW); glLoadIdentity(); - glBegin(GL_QUADS); + if (phases.size() > 1) { + glBindFramebuffer(GL_FRAMEBUFFER, fbo); + check_error(); + } - glTexCoord2f(0.0f, 1.0f); - glVertex2f(0.0f, 0.0f); + for (unsigned phase = 0; phase < phases.size(); ++phase) { + // Set up inputs and outputs for this phase. + if (phase == 0) { + // First phase reads from the input texture (which is already bound). + } else { + glBindTexture(GL_TEXTURE_2D, temp_textures[(phase + 1) % 2]); + check_error(); + } + if (phases[phase].input_needs_mipmaps) { + glGenerateMipmap(GL_TEXTURE_2D); + check_error(); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); + check_error(); + } else { + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + check_error(); + } - glTexCoord2f(1.0f, 1.0f); - glVertex2f(1.0f, 0.0f); + if (phase == phases.size() - 1) { + // Last phase goes directly to the screen. + glBindFramebuffer(GL_FRAMEBUFFER, 0); + check_error(); + } else { + glFramebufferTexture2D( + GL_FRAMEBUFFER, + GL_COLOR_ATTACHMENT0, + GL_TEXTURE_2D, + temp_textures[phase % 2], + 0); + } - glTexCoord2f(1.0f, 0.0f); - glVertex2f(1.0f, 1.0f); + // We have baked an upside-down transform into the quad coordinates, + // since the typical graphics program will have the origin at the upper-left, + // while OpenGL uses lower-left. In the next ones, however, the origin + // is all right, and we need to reverse that. + if (phase == 1) { + glTranslatef(0.0f, 1.0f, 0.0f); + glScalef(1.0f, -1.0f, 1.0f); + } - glTexCoord2f(0.0f, 0.0f); - glVertex2f(0.0f, 1.0f); + // Give the required parameters to all the effects. + glUseProgram(phases[phase].glsl_program_num); + check_error(); - glEnd(); - check_error(); + glUniform1i(glGetUniformLocation(phases[phase].glsl_program_num, "input_tex"), 0); + check_error(); + + unsigned sampler_num = 1; + for (unsigned i = phases[phase].start; i < phases[phase].end; ++i) { + char effect_id[256]; + sprintf(effect_id, "eff%d", i); + effects[i]->set_uniforms(phases[phase].glsl_program_num, effect_id, &sampler_num); + } + + // Now draw! + glBegin(GL_QUADS); + + glTexCoord2f(0.0f, 1.0f); + glVertex2f(0.0f, 0.0f); + + glTexCoord2f(1.0f, 1.0f); + glVertex2f(1.0f, 0.0f); + + glTexCoord2f(1.0f, 0.0f); + glVertex2f(1.0f, 1.0f); + + glTexCoord2f(0.0f, 0.0f); + glVertex2f(0.0f, 1.0f); + + glEnd(); + check_error(); + } } diff --git a/effect_chain.h b/effect_chain.h index 5b8ddbc..4abfb97 100644 --- a/effect_chain.h +++ b/effect_chain.h @@ -46,9 +46,18 @@ public: void render_to_screen(unsigned char *src); private: + struct Phase { + GLint glsl_program_num; + bool input_needs_mipmaps; + unsigned start, end; + }; + void normalize_to_linear_gamma(); void normalize_to_srgb(); + // Create a GLSL program computing effects [start, end>. + Phase compile_glsl_program(unsigned start_index, unsigned end_index); + unsigned width, height; ImageFormat input_format, output_format; std::vector effects; @@ -56,7 +65,11 @@ private: GLuint source_image_num; bool use_srgb_texture_format; - GLint glsl_program_num; + GLuint fbo; + GLuint temp_textures[2]; + + std::vector phases; + GLenum format, bytes_per_pixel; bool finalized; diff --git a/effect_id.h b/effect_id.h index 19923cc..291002b 100644 --- a/effect_id.h +++ b/effect_id.h @@ -14,6 +14,7 @@ enum EffectId { // Spatial. EFFECT_MIRROR, EFFECT_VIGNETTE, + EFFECT_BLUR, }; #endif // !defined(_EFFECT_ID_H) diff --git a/main.cpp b/main.cpp index 666a1ed..17cbeca 100644 --- a/main.cpp +++ b/main.cpp @@ -169,6 +169,7 @@ int main(int argc, char **argv) chain.add_input(inout_format); Effect *lift_gamma_gain_effect = chain.add_effect(EFFECT_LIFT_GAMMA_GAIN); Effect *saturation_effect = chain.add_effect(EFFECT_SATURATION); + Effect *blur_effect = chain.add_effect(EFFECT_BLUR); Effect *vignette_effect = chain.add_effect(EFFECT_VIGNETTE); //chain.add_effect(EFFECT_MIRROR); chain.add_output(inout_format); @@ -225,6 +226,7 @@ int main(int argc, char **argv) glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, 0); check_error(); + glLoadIdentity(); draw_hsv_wheel(0.0f, lift_rad, lift_theta, lift_v); draw_hsv_wheel(0.2f, gamma_rad, gamma_theta, gamma_v); draw_hsv_wheel(0.4f, gain_rad, gain_theta, gain_v);