source/blend.h

   1 #ifndef MSP_GL_BLEND_H_
   2 #define MSP_GL_BLEND_H_
   3
   4 #include <msp/strings/lexicalcast.h>
   5 #include "bindable.h"
   6 #include "gl.h"
   7 #include <msp/gl/extensions/ext_blend_minmax.h>
   8
   9 namespace Msp {
  10 namespace GL {
  11
  12 enum BlendEquation
  13 {
  14         ADD              = GL_FUNC_ADD,
  15         SUBTRACT         = GL_FUNC_SUBTRACT,
  16         REVERSE_SUBTRACT = GL_FUNC_REVERSE_SUBTRACT,
  17         MIN              = GL_MIN,
  18         MAX              = GL_MAX
  19 };
  20
  21 enum BlendFactor
  22 {
  23         ZERO = GL_ZERO,
  24         ONE = GL_ONE,
  25         SRC_COLOR = GL_SRC_COLOR,
  26         ONE_MINUS_SRC_COLOR = GL_ONE_MINUS_SRC_COLOR,
  27         SRC_ALPHA = GL_SRC_ALPHA,
  28         ONE_MINUS_SRC_ALPHA = GL_ONE_MINUS_SRC_ALPHA,
  29         DST_COLOR = GL_DST_COLOR,
  30         ONE_MINUS_DST_COLOR = GL_ONE_MINUS_DST_COLOR,
  31         DST_ALPHA = GL_DST_ALPHA,
  32         ONE_MINUS_DST_ALPHA = GL_ONE_MINUS_DST_ALPHA,
  33         CONSTANT_COLOR = GL_CONSTANT_COLOR,
  34         ONE_MINUS_CONSTANT_COLOR = GL_ONE_MINUS_CONSTANT_COLOR,
  35         CONSTANT_ALPHA = GL_CONSTANT_ALPHA,
  36         ONE_MINUS_CONSTANT_ALPHA = GL_ONE_MINUS_CONSTANT_ALPHA
  37 };
  38
  39 /**
  40 Blends incoming fragments with those already in the framebuffer.
  41 */
  42 class Blend: public Bindable<Blend>
  43 {
  44 private:
  45         BlendEquation eq;
  46         BlendFactor src_factor;
  47         BlendFactor dst_factor;
  48
  49 public:
  50         Blend();
  51         Blend(BlendFactor, BlendFactor);
  52         Blend(BlendEquation, BlendFactor, BlendFactor);
  53
  54         void bind() const;
  55
  56         static void unbind();
  57
  58         static const Blend &alpha();
  59         static const Blend &additive();
  60         static const Blend &additive_alpha();
  61 };
  62
  63 void operator>>(const LexicalConverter &, BlendFactor &);
  64 void operator<<(LexicalConverter &, BlendFactor);
  65
  66 } // namespace GL
  67 } // namespace Msp
  68
  69 #endif