Begin making SkPerlinNoiseShader const.

include/effects/SkPerlinNoiseShader.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 SkPerlinNoiseShader_DEFINED
 #define SkPerlinNoiseShader_DEFINED
 
+#include "SkBitmap.h"
+#include "SkPoint.h"
 #include "SkShader.h"
 
 /** \class SkPerlinNoiseShader
 
     SkPerlinNoiseShader creates an image using the Perlin turbulence function.
 
     It can produce tileable noise if asked to stitch tiles and provided a tile size.
     In order to fill a large area with repeating noise, set the stitchTiles flag to
     true, and render exactly a single tile of noise. Without this flag, the result
     will contain visible seams between tiles.
 
     The algorithm used is described here :
     http://www.w3.org/TR/SVG/filters.html#feTurbulenceElement
 */
 class SK_API SkPerlinNoiseShader : public SkShader {
-    struct PaintingData;
 public:
-    struct StitchData;
-
     /**
      *  About the noise types : the difference between the 2 is just minor tweaks to the algorithm,
      *  they're not 2 entirely different noises. The output looks different, but once the noise is
      *  generated in the [1, -1] range, the output is brought back in the [0, 1] range by doing :
      *  kFractalNoise_Type : noise * 0.5 + 0.5
      *  kTurbulence_Type   : abs(noise)
      *  Very little differences between the 2 types, although you can tell the difference visually.
      */
     enum Type {
         kFractalNoise_Type,
@@ skipping 22 matching lines @@
                                      int numOctaves, SkScalar seed,
                                      const SkISize* tileSize = NULL);
 
     virtual bool setContext(const SkBitmap& device, const SkPaint& paint,
                             const SkMatrix& matrix);
     virtual void shadeSpan(int x, int y, SkPMColor[], int count) SK_OVERRIDE;
     virtual void shadeSpan16(int x, int y, uint16_t[], int count) SK_OVERRIDE;
 
     virtual GrEffectRef* asNewEffect(GrContext* context, const SkPaint&) const SK_OVERRIDE;
 
+    struct StitchData {

[scroggo, 2014/03/04 22:26:34]

StitchData is now defined in the class declaration because
PaintingData.fStitchDataInit has moved into SkPerlinNoiseShader.

+        StitchData()
+            : fWidth(0)
+            , fWrapX(0)
+            , fHeight(0)
+            , fWrapY(0)
+        {}
+
+        bool operator==(const StitchData& other) const {
+            return fWidth == other.fWidth &&
+                   fWrapX == other.fWrapX &&
+                   fHeight == other.fHeight &&
+                   fWrapY == other.fWrapY;
+        }
+
+        int fWidth; // How much to subtract to wrap for stitching.
+        int fWrapX; // Minimum value to wrap.
+        int fHeight;
+        int fWrapY;
+    };
+
     SK_DEVELOPER_TO_STRING()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPerlinNoiseShader)
 
 protected:
     SkPerlinNoiseShader(SkReadBuffer&);
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkPerlinNoiseShader(SkPerlinNoiseShader::Type type, SkScalar baseFrequencyX,
                         SkScalar baseFrequencyY, int numOctaves, SkScalar seed,
                         const SkISize* tileSize = NULL);
-    virtual ~SkPerlinNoiseShader();
 
-    void setTileSize(const SkISize&);
+    SkScalar noise2D(int channel, const StitchData& stitchData, const SkPoint& noiseVector) const;
 
-    void initPaint(PaintingData& paintingData);
+    SkScalar calculateTurbulenceValueForPoint(int channel, StitchData& stitchData,
+                                              const SkPoint& point) const;
 
-    SkScalar noise2D(int channel, const PaintingData& paintingData,
-                     const StitchData& stitchData, const SkPoint& noiseVector);
+    SkPMColor shade(const SkPoint& point, StitchData& stitchData) const;
 
-    SkScalar calculateTurbulenceValueForPoint(int channel, const PaintingData& paintingData,
-                                              StitchData& stitchData, const SkPoint& point);
+    // TODO (scroggo): Investigate making fields const.
+    SkPerlinNoiseShader::Type fType;
+    SkVector                  fBaseFrequency;
+    int                       fNumOctaves;
+    // fSeed changes on each call to random.
+    mutable int               fSeed;

[scroggo, 2014/03/04 22:26:34]

fSeed is now an int, like PaintingData::fSeed was.

+    SkISize                   fTileSize;
+    bool                      fStitchTiles;
 
-    SkPMColor shade(const SkPoint& point, StitchData& stitchData);
+    static const int kBlockSize = 256;

[scroggo, 2014/03/04 22:26:34]

Now defined here for members referencing it that used to be on PaintingData.

+    static const int kBlockMask = kBlockSize - 1;
 
-    SkPerlinNoiseShader::Type fType;
-    SkScalar fBaseFrequencyX;
-    SkScalar fBaseFrequencyY;
-    int fNumOctaves;
-    SkScalar fSeed;
-    SkISize fTileSize;
-    bool fStitchTiles;
+    uint8_t     fLatticeSelector[kBlockSize];
+    uint16_t    fNoise[4][kBlockSize][2];
+    SkPoint     fGradient[4][kBlockSize];
+
+    StitchData  fStitchDataInit;
+
+    // These are caches. Instead of accessing directly, getPermutationsBitmap and getNoiseBitmap
+    // should be called.
+    mutable SkBitmap    fPermutationsBitmap;

[scroggo, 2014/03/04 22:26:34]

I changed these from pointers on fPaintingData to full members to avoid the
new/delete.

+    mutable SkBitmap    fNoiseBitmap;
+
+
+    // TODO (scroggo): Once setContext creates a new object, place this on that object.
     SkMatrix fMatrix;
 
-    PaintingData* fPaintingData;
+    void init();

[scroggo, 2014/03/04 22:26:34]

This should now be the only function that modifies any members (besides the ones
marked mutable). It is only called by the constructors.

+    const SkBitmap& getPermutationsBitmap() const;
+    const SkBitmap& getNoiseBitmap() const;
 
     typedef SkShader INHERITED;
 };
 
 #endif