Fix image filters for PDF backend.

src/pdf/SkPDFDevice.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkPDFDevice.h"
 
 #include "SkAnnotation.h"
+#include "SkBitmapDevice.h"
 #include "SkColor.h"
 #include "SkClipStack.h"
 #include "SkData.h"
 #include "SkDraw.h"
 #include "SkFontHost.h"
 #include "SkGlyphCache.h"
 #include "SkPaint.h"
 #include "SkPath.h"
 #include "SkPathOps.h"
 #include "SkPDFFont.h"
@@ skipping 539 matching lines @@
             SK_COMPILE_ASSERT(SkPaint::kStrokeAndFill_Style == 2,
                               enum_must_match_value);
             fContentStream->writeDecAsText(state.fTextFill);
             fContentStream->writeText(" Tr\n");
             currentEntry()->fTextFill = state.fTextFill;
         }
     }
 }
 
 SkBaseDevice* SkPDFDevice::onCreateDevice(const SkImageInfo& info, Usage usage) {
+    // PDF does not support image filters, so render them on CPU.
+    // Note that this rendering is done at "screen" resolution (100dpi), not
+    // printer resolution.
+    // FIXME: It may be possible to express some filters natively using PDF
+    // to improve quality and file size (http://skbug.com/3043)
+    if (kImageFilter_Usage == usage) {
+        return SkBitmapDevice::Create(info);
+    }
+
     SkMatrix initialTransform;
     initialTransform.reset();
     SkISize size = SkISize::Make(info.width(), info.height());
     return SkNEW_ARGS(SkPDFDevice, (size, size, initialTransform));
 }
 
 
 struct ContentEntry {
     GraphicStateEntry fState;
     SkDynamicMemoryWStream fContent;
@@ skipping 1613 matching lines @@
     SkAutoTUnref<SkPDFObject> image(
             SkPDFCreateImageObject(*bitmap, subset, fEncoder));
     if (!image) {
         return;
     }
 
     SkPDFUtils::DrawFormXObject(this->addXObjectResource(image.get()),
                                 &content.entry()->fContent);
 }