Move the 0.5 offset we add for aliased rendering to updateMatrix()

The old code set and unset a temporary matrix for every draw command
when doing aliased rendering. Instead, we just use a flag to indicate
that updateMatrix() should add the offset. This means the offset is
added only once. When doing lots of small rendering operations on a
(non-multisampled) QGLWidget, this gives up to 72% performance boost
on the SGX.

Reviewed-By: Kim

1 files changed, 3 insertions, 2 deletions

diff --git a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
index 8de4a82..4ace030 100644
--- a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
@@ -171,6 +171,7 @@ public:
             q(q_ptr),
             width(0), height(0),
             ctx(0),
+            addOffset(false),
             inverseScale(1),
             shaderManager(0),
             inRenderText(false)
@@ -246,8 +247,6 @@ public:
     QBrush currentBrush; // May not be the state's brush!
     const QBrush noBrush;
 
-    GLfloat     inverseScale;
-
     QGL2PEXVertexArray vertexCoordinateArray;
     QGL2PEXVertexArray textureCoordinateArray;
     QDataBuffer<GLfloat> opacityArray;
@@ -255,7 +254,9 @@ public:
     GLfloat staticVertexCoordinateArray[8];
     GLfloat staticTextureCoordinateArray[8];
 
+    bool addOffset; // When enabled, adds a 0.49,0.49 offset to matrix in updateMatrix
     GLfloat pmvMatrix[3][3];
+    GLfloat inverseScale;
 
     QGLEngineShaderManager* shaderManager;