Modifying SkTileGrid to support arbitrary query rectangles.

Exposing SkTileGrid functionality in the public API through SkTileGridPicture.
This patch also makes TileGrid and Rtree testable in gm, which revealed errors.

TEST=gm with '--tileGrid'
BUG=http://code.google.com/p/chromium/issues/detail?id=164636
Review URL: https://codereview.appspot.com/6933044

git-svn-id: http://skia.googlecode.com/svn/trunk@6783 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 29 insertions, 0 deletions

diff --git a/include/core/SkTileGridPicture.h b/include/core/SkTileGridPicture.h
new file mode 100644
index 0000000000..ef42f8c40b
--- /dev/null
+++ b/include/core/SkTileGridPicture.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkTileGridPicture_DEFINED
+#define SkTileGridPicture_DEFINED
+
+#include "SkPicture.h"
+
+/**
+ * Subclass of SkPicture that override the behavior of the
+ * kOptimizeForClippedPlayback_RecordingFlag by creating an SkTileGrid
+ * structure rather than an R-Tree. The tile grid has lower recording
+ * and playback costs, but is less effective at eliminating extraneous
+ * primitives for arbitrary query rectangles. It is most effective for
+ * tiled playback when the tile structure is known at record time.
+ */
+class SkTileGridPicture : public SkPicture {
+public:
+    SkTileGridPicture(int tileWidth, int tileHeight, int width, int height);
+    virtual SkBBoxHierarchy* createBBoxHierarchy() const SK_OVERRIDE;
+private:
+    int fTileWidth, fTileHeight, fXTileCount, fYTileCount;
+};
+
+#endif
\ No newline at end of file