Adding an option for pixelated rendering in SkPictureImageFilter

src/effects/SkPictureImageFilter.cpp

 /*
  * 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.
  */
 
 #include "SkPictureImageFilter.h"
 #include "SkDevice.h"
 #include "SkCanvas.h"
 #include "SkReadBuffer.h"
 #include "SkSurfaceProps.h"
 #include "SkWriteBuffer.h"
 #include "SkValidationUtils.h"
 
 SkPictureImageFilter::SkPictureImageFilter(const SkPicture* picture, uint32_t uniqueID)
     : INHERITED(0, 0, NULL, uniqueID)
     , fPicture(SkSafeRef(picture))
     , fCropRect(picture ? picture->cullRect() : SkRect::MakeEmpty())
-    , fPictureResolution(kDeviceSpace_PictureResolution) {
+    , fPictureResolution(kDeviceSpace_PictureResolution) 
+    , fFilterLevel(SkPaint::kLow_FilterLevel) {
 }
 
 SkPictureImageFilter::SkPictureImageFilter(const SkPicture* picture, const SkRect& cropRect,
-                                           uint32_t uniqueID, PictureResolution pictureResolution)
+                                           uint32_t uniqueID, PictureResolution pictureResolution,
+                                           SkPaint::FilterLevel filterLevel)
     : INHERITED(0, 0, NULL, uniqueID)
     , fPicture(SkSafeRef(picture))
     , fCropRect(cropRect)
-    , fPictureResolution(pictureResolution) {
+    , fPictureResolution(pictureResolution)
+    , fFilterLevel(filterLevel) {
 }
 
 SkPictureImageFilter::~SkPictureImageFilter() {
     SkSafeUnref(fPicture);
 }
 
 SkFlattenable* SkPictureImageFilter::CreateProc(SkReadBuffer& buffer) {
     SkAutoTUnref<SkPicture> picture;
     SkRect cropRect;
 
     if (!buffer.isCrossProcess()) {
         if (buffer.readBool()) {
             picture.reset(SkPicture::CreateFromBuffer(buffer));
         }
     } else {
         buffer.validate(!buffer.readBool());
     }
     buffer.readRect(&cropRect);
     PictureResolution pictureResolution;
     if (buffer.isVersionLT(SkReadBuffer::kPictureImageFilterResolution_Version)) {
         pictureResolution = kDeviceSpace_PictureResolution;
     } else {
         pictureResolution = (PictureResolution)buffer.readInt();
-    } 
+    }  
 
-    if (pictureResolution == kLocalSpace_PictureResolution) {
-        return CreateForLocalSpace(picture, cropRect);
+    if (kLocalSpace_PictureResolution == pictureResolution) {
+        //filterLevel is only serialized if pictureResolution is LocalSpace

[Stephen White, 2014/12/09 16:54:23]

Nit: space between // and "filterLevel"

+        SkPaint::FilterLevel filterLevel;
+        if (buffer.isVersionLT(SkReadBuffer::kPictureImageFilterLevel_Version)) {
+            filterLevel = SkPaint::kLow_FilterLevel;
+        } else {
+            filterLevel = (SkPaint::FilterLevel)buffer.readInt();
+        }
+        return CreateForLocalSpace(picture, cropRect, filterLevel);    
     }
     return Create(picture, cropRect);
 }
 
 void SkPictureImageFilter::flatten(SkWriteBuffer& buffer) const {
     if (!buffer.isCrossProcess()) {
         bool hasPicture = (fPicture != NULL);
         buffer.writeBool(hasPicture);
         if (hasPicture) {
             fPicture->flatten(buffer);
         }
     } else {
         buffer.writeBool(false);
     }
     buffer.writeRect(fCropRect);
     buffer.writeInt(fPictureResolution);
+    if (kLocalSpace_PictureResolution == fPictureResolution) {
+        buffer.writeInt(fFilterLevel);
+    }
 }
 
 bool SkPictureImageFilter::onFilterImage(Proxy* proxy, const SkBitmap&, const Context& ctx,
                                          SkBitmap* result, SkIPoint* offset) const {
     if (!fPicture) {
         offset->fX = offset->fY = 0;
         return true;
     }
 
     SkRect floatBounds;
     ctx.ctm().mapRect(&floatBounds, fCropRect);
     SkIRect bounds = floatBounds.roundOut();
     if (!bounds.intersect(ctx.clipBounds())) {
         return false;
     }
 
     if (bounds.isEmpty()) {
         offset->fX = offset->fY = 0;
         return true;
     }
 
     SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(bounds.width(), bounds.height()));
     if (NULL == device.get()) {
         return false;
     }
 
-    if (kLocalSpace_PictureResolution == fPictureResolution && 
-        (ctx.ctm().getType() & ~SkMatrix::kTranslate_Mask)) {
+    if (kDeviceSpace_PictureResolution == fPictureResolution || 
+        0 == (ctx.ctm().getType() & ~SkMatrix::kTranslate_Mask)) {
+        drawPictureAtDeviceResolution(proxy, device.get(), bounds, ctx);        
+    } else {
         drawPictureAtLocalResolution(proxy, device.get(), bounds, ctx);
-    } else {
-        drawPictureAtDeviceResolution(proxy, device.get(), bounds, ctx);
     }
 
     *result = device.get()->accessBitmap(false);
     offset->fX = bounds.fLeft;
     offset->fY = bounds.fTop;
     return true;
 }
 
 void SkPictureImageFilter::drawPictureAtDeviceResolution(Proxy* proxy, SkBaseDevice* device,
                                                          const SkIRect& deviceBounds,
@@ skipping 29 matching lines @@
     localCanvas.drawPicture(fPicture);
 
     // Pass explicit surface props, as the simplified canvas constructor discards device properties.
     // FIXME: switch back to the public constructor (and unfriend) after
     //        https://code.google.com/p/skia/issues/detail?id=3142 is fixed.
     SkCanvas canvas(device, proxy->surfaceProps(), SkCanvas::kDefault_InitFlags);
 
     canvas.translate(-SkIntToScalar(deviceBounds.fLeft), -SkIntToScalar(deviceBounds.fTop));
     canvas.concat(ctx.ctm());
     SkPaint paint;
-    paint.setFilterLevel(SkPaint::kLow_FilterLevel);
-    canvas.drawBitmap(localDevice.get()->accessBitmap(false), SkIntToScalar(localIBounds.fLeft), SkIntToScalar(localIBounds.fTop), &paint);
+    paint.setFilterLevel(fFilterLevel);
+    canvas.drawBitmap(localDevice.get()->accessBitmap(false), SkIntToScalar(localIBounds.fLeft),
+                      SkIntToScalar(localIBounds.fTop), &paint);
     //canvas.drawPicture(fPicture);
 }