source/colorcurve.cpp

   1 #include <cmath>
   2 #include "color.h"
   3 #include "colorcurve.h"
   4 #include "mesh.h"
   5 #include "shader.h"
   6 #include "texture2d.h"
   7
   8 using namespace std;
   9
  10 namespace Msp {
  11 namespace GL {
  12
  13 ColorCurve::ColorCurve():
  14         shprog("colorcurve.glsl"),
  15         quad(get_fullscreen_quad())
  16 {
  17         shdata.uniform("source", 0);
  18         shdata.uniform("curve", 1);
  19
  20         curve.storage(LUMINANCE, 256);
  21         curve.set_min_filter(LINEAR);
  22         curve.set_wrap(CLAMP_TO_EDGE);
  23
  24         set_peak(0.2);
  25         set_brightness(1.5);
  26         set_linear();
  27 }
  28
  29 void ColorCurve::set_peak(float p)
  30 {
  31         if(p<0 || p>1)
  32                 throw invalid_argument("ColorCurve::set_peak");
  33         shdata.uniform("peak", p);
  34 }
  35
  36 void ColorCurve::set_brightness(float b)
  37 {
  38         if(b<1)
  39                 throw invalid_argument("ColorCurve::set_brightness");
  40         shdata.uniform("brightness", b);
  41 }
  42
  43 void ColorCurve::set_gamma(float g)
  44 {
  45         if(g<0.1 || g>10)
  46                 throw invalid_argument("ColorCurve::set_gamma");
  47
  48         unsigned char curve_data[256];
  49         for(unsigned i=0; i<256; ++i)
  50                 curve_data[i] = pow(i/255.0f, 1/g)*255+0.5f;
  51         curve.image(0, LUMINANCE, UNSIGNED_BYTE, curve_data);
  52 }
  53
  54 void ColorCurve::set_srgb()
  55 {
  56         unsigned char curve_data[256];
  57         curve_data[0] = 0;
  58         for(unsigned i=1; i<256; ++i)
  59                 curve_data[i] = to_srgb(i/255.0f)*255+0.5f;
  60         curve.image(0, LUMINANCE, UNSIGNED_BYTE, curve_data);
  61 }
  62
  63 void ColorCurve::set_linear()
  64 {
  65         unsigned char curve_data[256];
  66         for(unsigned i=0; i<256; ++i)
  67                 curve_data[i] = i;
  68         curve.image(0, LUMINANCE, UNSIGNED_BYTE, curve_data);
  69 }
  70
  71 void ColorCurve::render(const Texture2D &color_buf, const Texture2D &)
  72 {
  73         Bind _bind_shader(shprog);
  74         shdata.apply();
  75         Bind _bind_mesh(quad);
  76         Bind _bind_tex(color_buf);
  77         Bind _bind_curve(curve, 1);
  78         quad.draw();
  79 }
  80
  81 } // namespace GL
  82 } // namespace Msp