Add support for advanced blend equations to our OpenGL QPainter

Mesa and NVidia have been supporting these extensions several years now.
It also means we can get rid of the dead unused code we had for advanced
compositions.

Change-Id: I6a2fcda13490abd977eb4cc3d8b34f186d05ca25
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>

1 files changed, 55 insertions, 104 deletions

diff --git a/src/gui/opengl/qopenglengineshadersource_p.h b/src/gui/opengl/qopenglengineshadersource_p.h
index a165643839..5d9ee8110b 100644
--- a/src/gui/opengl/qopenglengineshadersource_p.h
+++ b/src/gui/opengl/qopenglengineshadersource_p.h
@@ -403,25 +403,6 @@ static const char* const qopenglslMainFragmentShader_ImageArrays = "\n\
         gl_FragColor = srcPixel() * opacity; \n\
     }\n";
 
-static const char* const qopenglslMainFragmentShader_CMO = "\n\
-    uniform   lowp    float     globalOpacity; \n\
-    lowp vec4 srcPixel(); \n\
-    lowp vec4 applyMask(lowp vec4); \n\
-    lowp vec4 compose(lowp vec4); \n\
-    void main() \n\
-    { \n\
-        gl_FragColor = applyMask(compose(srcPixel()*globalOpacity))); \n\
-    }\n";
-
-static const char* const qopenglslMainFragmentShader_CM = "\n\
-    lowp vec4 srcPixel(); \n\
-    lowp vec4 applyMask(lowp vec4); \n\
-    lowp vec4 compose(lowp vec4); \n\
-    void main() \n\
-    { \n\
-        gl_FragColor = applyMask(compose(srcPixel())); \n\
-    }\n";
-
 static const char* const qopenglslMainFragmentShader_MO = "\n\
     uniform   lowp    float     globalOpacity; \n\
     lowp vec4 srcPixel(); \n\
@@ -439,23 +420,6 @@ static const char* const qopenglslMainFragmentShader_M = "\n\
         gl_FragColor = applyMask(srcPixel()); \n\
     }\n";
 
-static const char* const qopenglslMainFragmentShader_CO = "\n\
-    uniform   lowp    float     globalOpacity; \n\
-    lowp vec4 srcPixel(); \n\
-    lowp vec4 compose(lowp vec4); \n\
-    void main() \n\
-    { \n\
-        gl_FragColor = compose(srcPixel()*globalOpacity); \n\
-    }\n";
-
-static const char* const qopenglslMainFragmentShader_C = "\n\
-    lowp vec4 srcPixel(); \n\
-    lowp vec4 compose(lowp vec4); \n\
-    void main() \n\
-    { \n\
-        gl_FragColor = compose(srcPixel()); \n\
-    }\n";
-
 static const char* const qopenglslMainFragmentShader_O = "\n\
     uniform   lowp    float     globalOpacity; \n\
     lowp vec4 srcPixel(); \n\
@@ -513,22 +477,65 @@ static const char* const qopenglslRgbMaskFragmentShaderPass2 = "\n\
         return src * mask; \n\
     }\n";
 
+static const char* const qopenglslMultiplyCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_multiply) out;\n\
+    #endif\n";
+
+static const char* const qopenglslScreenCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_screen) out;\n\
+    #endif\n";
+
+static const char* const qopenglslOverlayCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_overlay) out;\n\
+    #endif\n";
+
+static const char* const qopenglslDarkenCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_darken) out;\n\
+    #endif\n";
+
+static const char* const qopenglslLightenCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_lighten) out;\n\
+    #endif\n";
+
+static const char* const qopenglslColorDodgeCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_colordodge) out;\n\
+    #endif\n";
+
+static const char* const qopenglslColorBurnCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_colorburn) out;\n\
+    #endif\n";
+
+static const char* const qopenglslHardLightCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_hardlight) out;\n\
+    #endif\n";
+
+static const char* const qopenglslSoftLightCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_softlight) out;\n\
+    #endif\n";
+
+static const char* const qopenglslDifferenceCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_difference) out;\n\
+    #endif\n";
+
+static const char* const qopenglslExclusionCompositionModeFragmentShader = "\n\
+    #ifdef GL_KHR_blend_equation_advanced\n\
+    layout(blend_support_exclusion) out;\n\
+    #endif\n";
+
 /*
     Left to implement:
         RgbMaskFragmentShader,
         RgbMaskWithGammaFragmentShader,
-
-        MultiplyCompositionModeFragmentShader,
-        ScreenCompositionModeFragmentShader,
-        OverlayCompositionModeFragmentShader,
-        DarkenCompositionModeFragmentShader,
-        LightenCompositionModeFragmentShader,
-        ColorDodgeCompositionModeFragmentShader,
-        ColorBurnCompositionModeFragmentShader,
-        HardLightCompositionModeFragmentShader,
-        SoftLightCompositionModeFragmentShader,
-        DifferenceCompositionModeFragmentShader,
-        ExclusionCompositionModeFragmentShader,
 */
 
 /*
@@ -880,29 +887,6 @@ static const char* const qopenglslMainFragmentShader_ImageArrays_core =
         fragColor = srcPixel() * opacity; \n\
     }\n";
 
-static const char* const qopenglslMainFragmentShader_CMO_core =
-    "#version 150 core\n\
-    out     vec4      fragColor; \n\
-    uniform float     globalOpacity; \n\
-    vec4 srcPixel(); \n\
-    vec4 applyMask(vec4); \n\
-    vec4 compose(vec4); \n\
-    void main() \n\
-    { \n\
-        fragColor = applyMask(compose(srcPixel()*globalOpacity))); \n\
-    }\n";
-
-static const char* const qopenglslMainFragmentShader_CM_core =
-    "#version 150 core\n\
-    out     vec4      fragColor; \n\
-    vec4 srcPixel(); \n\
-    vec4 applyMask(vec4); \n\
-    vec4 compose(vec4); \n\
-    void main() \n\
-    { \n\
-        fragColor = applyMask(compose(srcPixel())); \n\
-    }\n";
-
 static const char* const qopenglslMainFragmentShader_MO_core =
     "#version 150 core\n\
     out     vec4      fragColor; \n\
@@ -924,27 +908,6 @@ static const char* const qopenglslMainFragmentShader_M_core =
         fragColor = applyMask(srcPixel()); \n\
     }\n";
 
-static const char* const qopenglslMainFragmentShader_CO_core =
-    "#version 150 core\n\
-    out     vec4      fragColor; \n\
-    uniform float     globalOpacity; \n\
-    vec4 srcPixel(); \n\
-    vec4 compose(vec4); \n\
-    void main() \n\
-    { \n\
-        fragColor = compose(srcPixel()*globalOpacity); \n\
-    }\n";
-
-static const char* const qopenglslMainFragmentShader_C_core =
-    "#version 150 core\n\
-    out     vec4      fragColor; \n\
-    vec4 srcPixel(); \n\
-    vec4 compose(vec4); \n\
-    void main() \n\
-    { \n\
-        fragColor = compose(srcPixel()); \n\
-    }\n";
-
 static const char* const qopenglslMainFragmentShader_O_core =
     "#version 150 core\n\
     out     vec4      fragColor; \n\
@@ -1010,18 +973,6 @@ static const char* const qopenglslRgbMaskFragmentShaderPass2_core = "\n\
     Left to implement:
         RgbMaskFragmentShader_core,
         RgbMaskWithGammaFragmentShader_core,
-
-        MultiplyCompositionModeFragmentShader_core,
-        ScreenCompositionModeFragmentShader_core,
-        OverlayCompositionModeFragmentShader_core,
-        DarkenCompositionModeFragmentShader_core,
-        LightenCompositionModeFragmentShader_core,
-        ColorDodgeCompositionModeFragmentShader_core,
-        ColorBurnCompositionModeFragmentShader_core,
-        HardLightCompositionModeFragmentShader_core,
-        SoftLightCompositionModeFragmentShader_core,
-        DifferenceCompositionModeFragmentShader_core,
-        ExclusionCompositionModeFragmentShader_core,
 */
 
 QT_END_NAMESPACE