Adding an option for pixelated rendering in SkPictureImageFilter

include/effects/SkPictureImageFilter.h

 /*
  * Copyright 2013 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPictureImageFilter_DEFINED
 #define SkPictureImageFilter_DEFINED
 
 #include "SkImageFilter.h"
 #include "SkPicture.h"
 
 class SK_API SkPictureImageFilter : public SkImageFilter {
 public:
     /**
      *  Refs the passed-in picture.
      */
     static SkPictureImageFilter* Create(const SkPicture* picture, int32_t uniqueID = 0) {
         return SkNEW_ARGS(SkPictureImageFilter, (picture, uniqueID));
     }
 
     /**
      *  Refs the passed-in picture. cropRect can be used to crop or expand the destination rect when
      *  the picture is drawn. (No scaling is implied by the dest rect; only the CTM is applied.)
      */
     static SkPictureImageFilter* Create(const SkPicture* picture, const SkRect& cropRect,
                                         uint32_t uniqueID = 0) {
         return SkNEW_ARGS(SkPictureImageFilter, (picture, cropRect, uniqueID,
-                                                 kDeviceSpace_PictureResolution));
+                                                 kDeviceSpace_PictureMode));
     }
 
     /**
      *  Refs the passed-in picture. The picture is rasterized at a resolution that matches the
      *  local coordinate space. If the picture needs to be resampled for drawing it into the
-     *  destination canvas, bilinear filtering will be used. cropRect can be used to crop or
+     *  destination canvas, bilinear filtering will be used. If pixelated is true, then
+     *  nearest neighbor filtering is used instead. cropRect can be used to crop or
      *  expand the destination rect when the picture is drawn. (No scaling is implied by the
      *  dest rect; only the CTM is applied.)
      */
     static SkPictureImageFilter* CreateForLocalSpace(const SkPicture* picture,
                                                      const SkRect& cropRect,
-                                                     uint32_t uniqueID = 0) {
+                                                     uint32_t uniqueID = 0,
+                                                     bool pixelated = false) {

[Stephen White, 2014/12/09 16:22:10]

I think this should take a SkPaint::FilterLevel, rather than being an anonymous
bool. Apart from being more powerful, it's more self-documenting at the call
site.

I also think it should be before the uniqueID and cropRect, since that's the
calling pattern in other filters (cropRect and uniqueID come last).

         return SkNEW_ARGS(SkPictureImageFilter, (picture, cropRect, uniqueID,
-                                                 kLocalSpace_PictureResolution));
+            pixelated ? kLocalSpacePixelated_PictureMode : kLocalSpace_PictureMode));
     }
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPictureImageFilter)
 
 protected:
-    enum PictureResolution {
-        kDeviceSpace_PictureResolution,
-        kLocalSpace_PictureResolution
+    enum PictureMode {
+        kDeviceSpace_PictureMode,
+        kLocalSpace_PictureMode,
+        kLocalSpacePixelated_PictureMode
     };
 
     explicit SkPictureImageFilter(const SkPicture* picture, uint32_t uniqueID);
     SkPictureImageFilter(const SkPicture* picture, const SkRect& cropRect, uint32_t uniqueID,
-                         PictureResolution);
+                         PictureMode);
     virtual ~SkPictureImageFilter();
     /*  Constructs an SkPictureImageFilter object from an SkReadBuffer.
      *  Note: If the SkPictureImageFilter object construction requires bitmap
      *  decoding, the decoder must be set on the SkReadBuffer parameter by calling
      *  SkReadBuffer::setBitmapDecoder() before calling this constructor.
      *  @param SkReadBuffer Serialized picture data.
      */
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const Context&,
                                SkBitmap* result, SkIPoint* offset) const SK_OVERRIDE;
 
 private:
 
 
     void drawPictureAtDeviceResolution(Proxy*, SkBaseDevice*, const SkIRect& deviceBounds,
                                        const Context&) const;
     void drawPictureAtLocalResolution(Proxy*, SkBaseDevice*, const SkIRect& deviceBounds,
                                       const Context&) const;
 
     const SkPicture*      fPicture;
     SkRect                fCropRect;
-    PictureResolution     fPictureResolution;
+    PictureMode     fPictureMode;
     typedef SkImageFilter INHERITED;
 };
 
 #endif