Squash linear gamma back into the sRGB curve at the end.
[movit] / main.cpp
index 974fe53..4853179 100644 (file)
--- a/main.cpp
+++ b/main.cpp
@@ -5,11 +5,14 @@
 #define HEIGHT 720
 #define BUFFER_OFFSET(i) ((char *)NULL + (i))
 
+#include <string.h>
 #include <math.h>
 #include <time.h>
+#include <assert.h>
 
 #include <string>
 #include <vector>
+#include <map>
 
 #include <SDL/SDL.h>
 #include <SDL/SDL_opengl.h>
@@ -18,6 +21,8 @@
 #include <GL/gl.h>
 #include <GL/glext.h>
 
+#include "effect.h"
+#include "effect_chain.h"
 #include "util.h"
 #include "widgets.h"
 #include "texture_enum.h"
@@ -33,152 +38,6 @@ float lift_r = 0.0f, lift_g = 0.0f, lift_b = 0.0f;
 float gamma_r = 1.0f, gamma_g = 1.0f, gamma_b = 1.0f;
 float gain_r = 1.0f, gain_g = 1.0f, gain_b = 1.0f;
 
-struct ImageFormat {
-       enum { FORMAT_RGB, FORMAT_RGBA } format;
-
-       // Note: sRGB and 709 use the same colorspace primaries.
-       enum { COLORSPACE_sRGB, COLORSPACE_REC_601_525, COLORSPACE_REC_601_625, COLORSPACE_REC_709 } color_space;
-
-       // Note: Rec. 601 and 709 use the same gamma curve.
-       enum { LINEAR_LIGHT, GAMMA_sRGB, GAMMA_REC_601, GAMMA_REC_709 } gamma_curve;
-};
-
-enum EffectId {
-       // Mostly for internal use.
-       GAMMA_CONVERSION = 0,
-       RGB_PRIMARIES_CONVERSION,
-
-       // Color.
-       LIFT_GAMMA_GAIN,
-};
-
-class Effect {
-public: 
-       virtual bool needs_linear_light() { return true; }
-       virtual bool needs_srgb_primaries() { return true; }
-       virtual bool needs_many_samples() { return false; }
-       virtual bool needs_mipmaps() { return false; }
-       bool set_float(const std::string& key, float value);
-       bool set_float_array(const std::string&, const float *values, size_t num_values);
-
-private:
-       bool register_float(const std::string& key, float value);
-       bool register_float_array(const std::string& key, float *values, size_t num_values);
-};      
-
-class EffectChain {
-public:
-       void set_size(unsigned width, unsigned height);
-       void add_input(const ImageFormat &format);
-       Effect *add_effect(EffectId effect);
-       void add_output(const ImageFormat &format);
-
-       void render(unsigned char *src, unsigned char *dst);
-
-private:
-       unsigned width, height;
-       ImageFormat input_format, output_format;
-       std::vector<Effect *> effects;
-};
-
-GLhandleARB read_shader(const char* filename, GLenum type)
-{
-       static char buf[131072];
-       FILE *fp = fopen(filename, "r");
-       if (fp == NULL) {
-               perror(filename);
-               exit(1);
-       }
-
-       int len = fread(buf, 1, sizeof(buf), fp);
-       fclose(fp);
-
-       GLhandleARB obj = glCreateShaderObjectARB(type);
-       const GLchar* source[] = { buf };
-       const GLint length[] = { len };
-       glShaderSource(obj, 1, source, length);
-       glCompileShader(obj);
-
-       GLchar info_log[4096];
-       GLsizei log_length = sizeof(info_log) - 1;
-       glGetShaderInfoLog(obj, log_length, &log_length, info_log);
-       info_log[log_length] = 0; 
-       printf("shader compile log: %s\n", info_log);
-
-       GLint status;
-       glGetShaderiv(obj, GL_COMPILE_STATUS, &status);
-       if (status == GL_FALSE) {
-               exit(1);
-       }
-
-       return obj;
-}
-
-void draw_picture_quad(GLint prog, int frame)
-{
-       glUseProgramObjectARB(prog);
-       check_error();
-
-       glActiveTexture(GL_TEXTURE0);
-       glBindTexture(GL_TEXTURE_2D, SOURCE_IMAGE);
-       glUniform1i(glGetUniformLocation(prog, "tex"), 0);
-
-       glActiveTexture(GL_TEXTURE1);
-       glBindTexture(GL_TEXTURE_1D, SRGB_LUT);
-       glUniform1i(glGetUniformLocation(prog, "srgb_tex"), 1);
-
-       glActiveTexture(GL_TEXTURE2);
-       glBindTexture(GL_TEXTURE_1D, SRGB_REVERSE_LUT);
-       glUniform1i(glGetUniformLocation(prog, "srgb_reverse_tex"), 2);
-
-       glUniform3f(glGetUniformLocation(prog, "lift"), lift_r, lift_g, lift_b);
-       //glUniform3f(glGetUniformLocation(prog, "gamma"), gamma_r, gamma_g, gamma_b);
-       glUniform3f(glGetUniformLocation(prog, "inv_gamma_22"),
-                   2.2f / gamma_r,
-                   2.2f / gamma_g,
-                   2.2f / gamma_b);
-       glUniform3f(glGetUniformLocation(prog, "gain_pow_inv_gamma"),
-                   pow(gain_r, 1.0f / gamma_r),
-                   pow(gain_g, 1.0f / gamma_g),
-                   pow(gain_b, 1.0f / gamma_b));
-       glUniform1f(glGetUniformLocation(prog, "saturation"), saturation);
-
-       glDisable(GL_BLEND);
-       check_error();
-       glDisable(GL_DEPTH_TEST);
-       check_error();
-       glDepthMask(GL_FALSE);
-       check_error();
-
-       glMatrixMode(GL_PROJECTION);
-       glLoadIdentity();
-       glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0);
-
-       glMatrixMode(GL_MODELVIEW);
-       glLoadIdentity();
-
-       glClearColor(1.0f, 0.0f, 0.0f, 1.0f);
-//     glClear(GL_COLOR_BUFFER_BIT);
-       check_error();
-
-       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();
-}
-
 void update_hsv()
 {
        hsv2rgb(lift_theta, lift_rad, lift_v, &lift_r, &lift_g, &lift_b);
@@ -214,7 +73,7 @@ void mouse(int x, int y)
        update_hsv();
 }
 
-void load_texture(const char *filename)
+unsigned char *load_image(const char *filename, unsigned *w, unsigned *h)
 {
        SDL_Surface *img = IMG_Load(filename);
        if (img == NULL) {
@@ -253,17 +112,30 @@ void load_texture(const char *filename)
        }
        SDL_UnlockSurface(img);
 
+       *w = img->w;
+       *h = img->h;
+
+       SDL_FreeSurface(img);
+
+       return dst_pixels;
+}
+
+void load_texture(const char *filename)
+{
+       unsigned w, h;
+       unsigned char *pixels = load_image(filename, &w, &h);
+
 #if 1
        // we will convert to sRGB in the shader
-       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, img->w, img->h, 0, GL_RGB, GL_UNSIGNED_BYTE, dst_pixels);
+       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, w, h, 0, GL_RGB, GL_UNSIGNED_BYTE, pixels);
        check_error();
 #else
        // implicit sRGB conversion in hardware
-       glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8, img->w, img->h, 0, GL_RGB, GL_UNSIGNED_BYTE, dst_pixels);
+       glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8, w, h, 0, GL_RGB, GL_UNSIGNED_BYTE, pixels);
        check_error();
 #endif
-       free(dst_pixels);
-       SDL_FreeSurface(img);
+
+       free(pixels);
 }
 
 void write_ppm(const char *filename, unsigned char *screenbuf)
@@ -301,7 +173,21 @@ int main(int argc, char **argv)
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        check_error();
 
-       load_texture("blg_wheels_woman_1.jpg");
+       unsigned img_w, img_h;
+       unsigned char *src_img = load_image("blg_wheels_woman_1.jpg", &img_w, &img_h);
+
+       EffectChain chain(WIDTH, HEIGHT);
+
+       ImageFormat inout_format;
+       inout_format.pixel_format = FORMAT_RGB;
+       inout_format.color_space = COLORSPACE_sRGB;
+       inout_format.gamma_curve = GAMMA_sRGB;
+
+       chain.add_input(inout_format);
+       Effect *lift_gamma_gain_effect = chain.add_effect(LIFT_GAMMA_GAIN);
+       chain.add_output(inout_format);
+       chain.finalize();
+
        //glGenerateMipmap(GL_TEXTURE_2D);
        //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 4);
        //check_error();
@@ -357,8 +243,8 @@ int main(int argc, char **argv)
        update_hsv();
 
        int prog = glCreateProgram();
-       GLhandleARB vs_obj = read_shader("vs.glsl", GL_VERTEX_SHADER);
-       GLhandleARB fs_obj = read_shader("fs.glsl", GL_FRAGMENT_SHADER);
+       GLhandleARB vs_obj = compile_shader(read_file("vs.glsl"), GL_VERTEX_SHADER);
+       GLhandleARB fs_obj = compile_shader(read_file("fs.glsl"), GL_FRAGMENT_SHADER);
        glAttachObjectARB(prog, vs_obj);
        check_error();
        glAttachObjectARB(prog, fs_obj);
@@ -395,7 +281,7 @@ int main(int argc, char **argv)
 
                ++frame;
 
-               draw_picture_quad(prog, frame);
+               chain.render_to_screen(src_img);
                
                glReadPixels(0, 0, WIDTH, HEIGHT, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, BUFFER_OFFSET(0));
                check_error();