source/effects/colorcurve.cpp

   1 #include <cmath>
   2 #include "color.h"
   3 #include "colorcurve.h"
   4 #include "mesh.h"
   5 #include "renderer.h"
   6 #include "resources.h"
   7 #include "shader.h"
   8 #include "texture2d.h"
   9
  10 using namespace std;
  11
  12 namespace Msp {
  13 namespace GL {
  14
  15 ColorCurve::ColorCurve(Resources &resources):
  16         shprog(resources.get<Program>("_colorcurve.glsl.shader")),
  17         quad(resources.get<Mesh>("_fullscreen_quad.mesh")),
  18         linear_sampler(resources.get<Sampler>("_linear_clamp.samp")),
  19         nearest_sampler(resources.get<Sampler>("_nearest_clamp.samp"))
  20 {
  21         curve.storage(LUMINANCE8, 256, 1);
  22
  23         set_exposure_adjust(0.0f);
  24         set_brightness_response(0.4f);
  25         set_linear();
  26 }
  27
  28 void ColorCurve::set_exposure_adjust(float e)
  29 {
  30         shdata.uniform("exposure", pow(2.0f, e));
  31 }
  32
  33 void ColorCurve::set_brightness_response(float b)
  34 {
  35         if(b<=0 || b>1)
  36                 throw invalid_argument("ColorCurve::set_brightness_response");
  37         float t = (b<1 ? pow(b, 1/(1-b)) : 0.0f);
  38         shdata.uniform("brightness_response", b, t, pow(t, b));
  39 }
  40
  41 void ColorCurve::set_gamma(float g)
  42 {
  43         if(g<0.1 || g>10)
  44                 throw invalid_argument("ColorCurve::set_gamma");
  45
  46         unsigned char curve_data[256];
  47         for(unsigned i=0; i<256; ++i)
  48                 curve_data[i] = pow(i/255.0f, 1/g)*255+0.5f;
  49         curve.image(0, curve_data);
  50 }
  51
  52 void ColorCurve::set_srgb()
  53 {
  54         unsigned char curve_data[256];
  55         curve_data[0] = 0;
  56         for(unsigned i=1; i<256; ++i)
  57                 curve_data[i] = to_srgb(i/255.0f)*255+0.5f;
  58         curve.image(0, curve_data);
  59 }
  60
  61 void ColorCurve::set_linear()
  62 {
  63         unsigned char curve_data[256];
  64         for(unsigned i=0; i<256; ++i)
  65                 curve_data[i] = i;
  66         curve.image(0, curve_data);
  67 }
  68
  69 void ColorCurve::render(Renderer &renderer, const Texture2D &color_buf, const Texture2D &)
  70 {
  71         Renderer::Push push(renderer);
  72         renderer.set_shader_program(&shprog, &shdata);
  73         renderer.set_texture("source", &color_buf, &nearest_sampler);
  74         renderer.set_texture("curve", &curve, &linear_sampler);
  75         quad.draw(renderer);
  76 }
  77
  78
  79 ColorCurve::Template::Template():
  80         exposure_adjust(0.0f),
  81         brightness_response(0.4f),
  82         gamma(1.0f),
  83         srgb(false)
  84 { }
  85
  86 ColorCurve *ColorCurve::Template::create(Resources &res, unsigned, unsigned) const
  87 {
  88         RefPtr<ColorCurve> colorcurve = new ColorCurve(res);
  89         colorcurve->set_exposure_adjust(exposure_adjust);
  90         colorcurve->set_brightness_response(brightness_response);
  91         if(srgb)
  92                 colorcurve->set_srgb();
  93         else
  94                 colorcurve->set_gamma(gamma);
  95         return colorcurve.release();
  96 }
  97
  98
  99 ColorCurve::Template::Loader::Loader(Template &t):
 100         DataFile::DerivedObjectLoader<Template, PostProcessor::Template::Loader>(t)
 101 {
 102         add("brightness_response", &Template::brightness_response);
 103         add("exposure_adjust", &Template::exposure_adjust);
 104         add("gamma", &Loader::gamma);
 105         add("srgb", &Loader::srgb);
 106 }
 107
 108 void ColorCurve::Template::Loader::gamma(float g)
 109 {
 110         obj.gamma = g;
 111         obj.srgb = false;
 112 }
 113
 114 void ColorCurve::Template::Loader::srgb()
 115 {
 116         obj.srgb = true;
 117 }
 118
 119 } // namespace GL
 120 } // namespace Msp