BitmapTextBatch and BitmapTextBlob

src/gpu/GrBitmapTextContext.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrBitmapTextContext_DEFINED
 #define GrBitmapTextContext_DEFINED
 
 #include "GrTextContext.h"
 
 #include "GrGeometryProcessor.h"
+#include "SkTHash.h"
+
+class GrBatchTextStrike;
+class GrPipelineBuilder;
+
+/*
+ * This class implements GrTextContext using standard bitmap fonts, and can also process textblobs.
+ * TODO replace GrBitmapTextContext
+ */
+class GrBitmapTextContextB : public GrTextContext {
+public:
+    static GrBitmapTextContextB* Create(GrContext*, SkGpuDevice*, const SkDeviceProperties&);
+
+    virtual ~GrBitmapTextContextB();
+
+private:
+    GrBitmapTextContextB(GrContext*, SkGpuDevice*, const SkDeviceProperties&);
+
+    bool canDraw(const GrRenderTarget*, const GrClip&, const GrPaint&,
+                 const SkPaint&, const SkMatrix& viewMatrix) override;
+
+    void onDrawText(GrRenderTarget*, const GrClip&, const GrPaint&, const SkPaint&,
+                    const SkMatrix& viewMatrix, const char text[], size_t byteLength,
+                    SkScalar x, SkScalar y, const SkIRect& regionClipBounds) override;
+    void onDrawPosText(GrRenderTarget*, const GrClip&, const GrPaint&, const SkPaint&,
+                       const SkMatrix& viewMatrix,
+                       const char text[], size_t byteLength,
+                       const SkScalar pos[], int scalarsPerPosition,
+                       const SkPoint& offset, const SkIRect& regionClipBounds) override;
+    void drawTextBlob(GrRenderTarget*, const GrClip&, const SkPaint&,
+                      const SkMatrix& viewMatrix, const SkTextBlob*, SkScalar x, SkScalar y,
+                      SkDrawFilter*, const SkIRect& clipBounds) override;
+
+    void init(GrRenderTarget*, const GrClip&, const GrPaint&, const SkPaint&,
+              const SkIRect& regionClipBounds);
+
+    /*
+     * A BitmapTextBlob contains a fully processed SkTextBlob, suitable for nearly immediate drawing
+     * on the GPU.  These are initially created with valid positions and colors, but invalid
+     * texture coordinates.  The BitmapTextBlob itself has a few Blob-wide properties, and also
+     * consists of a number of runs.  Runs inside a blob are flushed individually so they can be
+     * reordered.
+     *
+     * The only thing(aside from a memcopy) required to flush a BitmapTextBlob is to ensure that
+     * the GrAtlas will not evict anything the Blob needs.
+     * TODO this is currently a bug
+     */
+    struct BitmapTextBlob : public SkRefCnt {
+        // Each Run inside of the blob can have its texture coordinates regenerated if required.
+        // To determine if regeneration is necessary, fAtlasGeneration is used.  If there have been
+        // any evictions inside of the atlas, then we will simply regenerate Runs.  We could track
+        // this at a more fine grained level, but its not clear if this is worth it, as evictions
+        // should be fairly rare.
+        // One additional point, each run can contain glyphs with any of the three mask formats.
+        // We maintain separate arrays for each format type, and flush them separately.  In practice
+        // most of the time a run will have the same format type
+        struct Run {
+            Run() : fColor(GrColor_ILLEGAL) { fVertexBounds.setLargestInverted(); }
+            struct PerFormatInfo {
+                PerFormatInfo() : fAtlasGeneration(GrBatchAtlas::kInvalidAtlasGeneration) {}
+                SkTDArray<unsigned char> fVertices;
+                SkTDArray<GrGlyph::PackedID> fGlyphIDs;
+                uint64_t fAtlasGeneration;
+            };
+            SkAutoTUnref<const SkData> fDescriptor;
+            SkAutoTUnref<SkTypeface> fTypeface;
+            PerFormatInfo fInfos[kMaskFormatCount];
+            SkRect fVertexBounds;
+            GrColor fColor;
+        };
+        SkSTArray<1, Run, true> fRuns;
+        struct BigGlyph {
+            BigGlyph(const SkPath& path, int vx, int vy) : fPath(path), fVx(vx), fVy(vy) {}
+            SkPath fPath;
+            int fVx;
+            int fVy;
+        };
+        SkTArray<BigGlyph> fBigGlyphs;
+        SkTextBlob* fBlob;
+        SkMatrix fViewMatrix;
+        SkScalar fX;
+        SkScalar fY;
+        SkPaint::Style fStyle;
+
+        static uint32_t Hash(const uint32_t& key) {
+            return SkChecksum::Mix(key);
+        }
+    };
+
+    void appendGlyph(BitmapTextBlob*, int runIndex, GrGlyph::PackedID, int left, int top,
+                     GrFontScaler*, const SkIRect& clipRect);
+    void flushSubRun(GrDrawTarget*, BitmapTextBlob*, int i, GrPipelineBuilder*, GrMaskFormat,
+               GrColor color, int paintAlpha);
+    void flush(GrDrawTarget*, BitmapTextBlob*, GrRenderTarget*, const GrPaint&, const GrClip&,
+               const SkMatrix& viewMatrix, int paintAlpha);
+
+    void internalDrawText(BitmapTextBlob*, int runIndex, const SkPaint&,
+                          const SkMatrix& viewMatrix, const char text[], size_t byteLength,
+                          SkScalar x, SkScalar y, const SkIRect& clipRect);
+    void internalDrawPosText(BitmapTextBlob*, int runIndex, const SkPaint&,
+                             const SkMatrix& viewMatrix,
+                             const char text[], size_t byteLength,
+                             const SkScalar pos[], int scalarsPerPosition,
+                             const SkPoint& offset, const SkIRect& clipRect);
+
+    static inline bool MustRegenerateBlob(const BitmapTextBlob&, const SkPaint&,
+                                          const SkMatrix& viewMatrix, SkScalar x, SkScalar y);
+    void regenerateTextBlob(BitmapTextBlob* bmp, const SkPaint& skPaint, const SkMatrix& viewMatrix,
+                            const SkTextBlob* blob, SkScalar x, SkScalar y,
+                            SkDrawFilter* drawFilter, const SkIRect& clipRect);
+
+    GrBatchTextStrike* fCurrStrike;
+
+    // TODO use real cache
+    static void ClearCacheEntry(uint32_t key, BitmapTextBlob**);
+    SkTHashMap<uint32_t, BitmapTextBlob*, BitmapTextBlob::Hash> fCache;
+
+    friend class BitmapTextBatch;
+
+    typedef GrTextContext INHERITED;
+};
 
 class GrTextStrike;
 
 /*
  * This class implements GrTextContext using standard bitmap fonts
  */
 class GrBitmapTextContext : public GrTextContext {
 public:
     static GrBitmapTextContext* Create(GrContext*, SkGpuDevice*,  const SkDeviceProperties&);
 
@@ skipping 29 matching lines @@
 
     void init(GrRenderTarget*, const GrClip&, const GrPaint&, const SkPaint&,
               const SkIRect& regionClipBounds);
     void appendGlyph(GrGlyph::PackedID, SkFixed left, SkFixed top, GrFontScaler*);
     bool uploadGlyph(GrGlyph*, GrFontScaler*);
     void flush();                 // automatically called by destructor
     void finish();
 };
 
 #endif