Simplify renderer code

Move some caching functionality into GraphicsContext, as this
has nothing to do with Rendering logic, but only reduces
amount of OpenGL calls.

Change-Id: I5a3c858e893da1498cb4bace9a212fec6b1de93e
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/src/render/graphicshelpers/graphicscontext_p.h b/src/render/graphicshelpers/graphicscontext_p.h
index c3ab61215..d61679ec2 100644
--- a/src/render/graphicshelpers/graphicscontext_p.h
+++ b/src/render/graphicshelpers/graphicscontext_p.h
@@ -106,7 +106,7 @@ public:
 
     int id() const; // unique, small integer ID of this context
 
-    bool beginDrawing(QSurface *surface, const QColor &color);
+    bool beginDrawing(QSurface *surface);
     void clearBackBuffer(QClearBuffers::BufferType buffers);
     void endDrawing(bool swapBuffers);
 
@@ -255,6 +255,11 @@ private:
     QBitArray m_pinnedTextureUnits;
     QVector<TextureScope> m_textureScopes;
 
+    // cache some current state, to make sure we don't issue unnecessary GL calls
+    int m_currClearStencilValue;
+    float m_currClearDepthValue;
+    QColor m_currClearColorValue;
+
     // recency score for all render-textures we've seen. Higher scores
     // mean more recently used.
     QHash<uint, int> m_textureScores;