source/blend.h

   1 #ifndef MSP_GL_BLEND_H_
   2 #define MSP_GL_BLEND_H_
   3
   4 #include "bindable.h"
   5 #include "gl.h"
   6 #include <msp/gl/extensions/ext_blend_minmax.h>
   7
   8 namespace Msp {
   9 namespace GL {
  10
  11 enum BlendEquation
  12 {
  13         ADD              = GL_FUNC_ADD,
  14         SUBTRACT         = GL_FUNC_SUBTRACT,
  15         REVERSE_SUBTRACT = GL_FUNC_REVERSE_SUBTRACT,
  16         MIN              = GL_MIN,
  17         MAX              = GL_MAX
  18 };
  19
  20 enum BlendFactor
  21 {
  22         ZERO = GL_ZERO,
  23         ONE = GL_ONE,
  24         SRC_COLOR = GL_SRC_COLOR,
  25         ONE_MINUS_SRC_COLOR = GL_ONE_MINUS_SRC_COLOR,
  26         SRC_ALPHA = GL_SRC_ALPHA,
  27         ONE_MINUS_SRC_ALPHA = GL_ONE_MINUS_SRC_ALPHA,
  28         DST_COLOR = GL_DST_COLOR,
  29         ONE_MINUS_DST_COLOR = GL_ONE_MINUS_DST_COLOR,
  30         DST_ALPHA = GL_DST_ALPHA,
  31         ONE_MINUS_DST_ALPHA = GL_ONE_MINUS_DST_ALPHA,
  32         CONSTANT_COLOR = GL_CONSTANT_COLOR,
  33         ONE_MINUS_CONSTANT_COLOR = GL_ONE_MINUS_CONSTANT_COLOR,
  34         CONSTANT_ALPHA = GL_CONSTANT_ALPHA,
  35         ONE_MINUS_CONSTANT_ALPHA = GL_ONE_MINUS_CONSTANT_ALPHA
  36 };
  37
  38 /**
  39 Blends incoming fragments with those already in the framebuffer.
  40 */
  41 class Blend: public Bindable<Blend>
  42 {
  43 private:
  44         BlendEquation eq;
  45         BlendFactor src_factor;
  46         BlendFactor dst_factor;
  47
  48 public:
  49         Blend();
  50         Blend(BlendFactor, BlendFactor);
  51         Blend(BlendEquation, BlendFactor, BlendFactor);
  52
  53         void bind() const;
  54
  55         static void unbind();
  56
  57         static const Blend &alpha();
  58         static const Blend &additive();
  59         static const Blend &additive_alpha();
  60 };
  61
  62 } // namespace GL
  63 } // namespace Msp
  64
  65 #endif