Added documentation of stage/TU allocation
http://codereview.appspot.com/6199058/
git-svn-id: http://skia.googlecode.com/svn/trunk@3888 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/gpu/GrTextContext.h b/include/gpu/GrTextContext.h
index 588ae6e..ab1a344 100644
--- a/include/gpu/GrTextContext.h
+++ b/include/gpu/GrTextContext.h
@@ -22,6 +22,11 @@
class SkGpuDevice;
class SkPaint;
+/**
+ * Derived classes can use stages GrPaint::kTotalStages through
+ * GrDrawState::kNumStages-1. The stages before GrPaint::kTotalStages
+ * are reserved for setting up the draw (i.e., textures and filter masks).
+ */
class GrTextContext: public GrRefCnt {
protected:
GrContext* fContext;