Instead of turning clipping off during AA, clip to the offscreen tile when

we're writing to it, then restore the onscreen clip when copying it back
to screen. Speeds up rendering of web pages with paths >> tile size.

git-svn-id: http://skia.googlecode.com/svn/trunk@1899 2bbb7eff-a529-9590-31e7-b0007b416f81

diff --git a/gpu/src/GrContext.cpp b/gpu/src/GrContext.cpp
index dcaba1d..ef5ad11 100644 (file)
--- a/gpu/src/GrContext.cpp
+++ b/gpu/src/GrContext.cpp
@@ -545,6 +545,7 @@ struct GrContext::OffscreenRecord {
     GrTextureEntry*                fEntry0;
     GrTextureEntry*                fEntry1;
     GrDrawTarget::SavedDrawState   fSavedState;
+    GrClip                         fClip;
 };
 
 bool GrContext::doOffscreenAA(GrDrawTarget* target, 
@@ -658,6 +659,8 @@ bool GrContext::prepareForOffscreenAA(GrDrawTarget* target,
     record->fTileCountX = GrIDivRoundUp(boundW, record->fTileSizeX);
     record->fTileCountY = GrIDivRoundUp(boundH, record->fTileSizeY);
 
+    record->fClip = target->getClip();
+
     target->saveCurrentDrawState(&record->fSavedState);
     return true;
 }
@@ -684,15 +687,13 @@ void GrContext::setupOffscreenAAPass1(GrDrawTarget* target,
     scaleM.setScale(record->fScale * GR_Scalar1, record->fScale * GR_Scalar1);
     target->postConcatViewMatrix(scaleM);
 
-    // clip gets applied in second pass
-    target->disableState(GrDrawTarget::kClip_StateBit);
-
     int w = (tileX == record->fTileCountX-1) ? boundRect.fRight - left :
                                                record->fTileSizeX;
     int h = (tileY == record->fTileCountY-1) ? boundRect.fBottom - top :
                                                record->fTileSizeY;
     GrIRect clear = SkIRect::MakeWH(record->fScale * w, 
                                     record->fScale * h);
+    target->setClip(GrClip(clear));
 #if 0
     // visualize tile boundaries by setting edges of offscreen to white
     // and interior to tranparent. black.
@@ -779,6 +780,7 @@ void GrContext::doOffscreenAAPass2(GrDrawTarget* target,
     int stageMask = paint.getActiveStageMask();
 
     target->restoreDrawState(record->fSavedState);
+    target->setClip(record->fClip);
 
     if (stageMask) {
         GrMatrix invVM;