Implement text rendering with NVPR

src/gpu/GrStencilAndCoverTextContext.h

+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrStencilAndCoverTextContext_DEFINED
+#define GrStencilAndCoverTextContext_DEFINED
+
+#include "GrTextContext.h"
+#include "GrDrawState.h"
+#include "SkStrokeRec.h"
+
+class GrTextStrike;
+class GrPath;
+
+/*
+ * This class implements text rendering using stencil and cover path rendering
+ * (by the means of GrDrawTarget::drawPath).
+ * This class exposes the functionality through GrTextContext interface.
+ */
+class GrStencilAndCoverTextContext : public GrTextContext {
+public:
+    GrStencilAndCoverTextContext(GrContext*, const SkDeviceProperties&);
+    virtual ~GrStencilAndCoverTextContext();
+
+    virtual void drawText(const GrPaint&, const SkPaint&, const char text[],
+                          size_t byteLength,
+                          SkScalar x, SkScalar y) SK_OVERRIDE;
+    virtual void drawPosText(const GrPaint&, const SkPaint&,
+                             const char text[], size_t byteLength,
+                             const SkScalar pos[], SkScalar constY,
+                             int scalarsPerPosition) SK_OVERRIDE;
+
+    virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE;
+
+private:
+    void init(const GrPaint&, const SkPaint&, size_t textByteLength);
+    void appendGlyph(GrGlyph::PackedID, const SkPoint&,
+                     GrTextStrike*, GrFontScaler*);
+    void finish();
+
+    GrDrawState::AutoRestoreEffects fStateRestore;
+    SkScalar fTextRatio;
+    SkStrokeRec fStroke;
+    SkPaint::Style fStyle;
+    SkTDArray<const GrPath*> fPaths;
+    SkTDArray<SkMatrix> fTransforms;
+    SkPath fTmpPath;
+};
+
+#endif