source/blend.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgl
   4 Copyright © 2008, 2010  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include "blend.h"
   9 #include "extension.h"
  10 #include "version_1_2.h"
  11
  12 namespace Msp {
  13 namespace GL {
  14
  15 Blend::Blend():
  16         eq(ADD),
  17         src_factor(ONE),
  18         dst_factor(ZERO)
  19 { }
  20
  21 Blend::Blend(BlendFactor sf, BlendFactor df):
  22         eq(ADD),
  23         src_factor(sf),
  24         dst_factor(df)
  25 { }
  26
  27 Blend::Blend(BlendEquation e, BlendFactor sf, BlendFactor df):
  28         eq(e),
  29         src_factor(sf),
  30         dst_factor(df)
  31 {
  32         if(eq!=ADD)
  33                 static RequireVersion _ver(1, 2);
  34 }
  35
  36 void Blend::bind() const
  37 {
  38         if(set_current(this))
  39         {
  40                 glEnable(GL_BLEND);
  41                 if(glBlendEquation)
  42                         glBlendEquation(eq);
  43                 glBlendFunc(src_factor, dst_factor);
  44         }
  45 }
  46
  47 void Blend::unbind()
  48 {
  49         if(set_current(0))
  50                 glDisable(GL_BLEND);
  51 }
  52
  53 const Blend &Blend::alpha()
  54 {
  55         static Blend blend(SRC_ALPHA, ONE_MINUS_SRC_ALPHA);
  56         return blend;
  57 }
  58
  59 } // namespace GL
  60 } // namespace Msp