Use newImageSnapshot() to get an image from a Canvas

Source/platform/graphics/BitmapPattern.cpp

 /*
  * Copyright (C) 2006, 2007, 2008 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2013 Google, Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
-#include "platform/graphics/Pattern.h"
+#include "platform/graphics/BitmapPattern.h"
 
-#include <v8.h>
+
 #include "SkCanvas.h"
 #include "SkColorShader.h"
 #include "platform/graphics/skia/SkiaUtils.h"
-
+#include <v8.h>
 
 namespace WebCore {
 
-Pattern::Pattern(PassRefPtr<Image> image, bool repeatX, bool repeatY)
-    : m_repeatX(repeatX)
-    , m_repeatY(repeatY)
-    , m_externalMemoryAllocated(0)
+BitmapPattern::BitmapPattern(PassRefPtr<Image> image, bool repeatX, bool repeatY)
+: Pattern(repeatX, repeatY)
 {
     if (image) {
         m_tileImage = image->nativeImageForCurrentFrame();
     }
 }
 
-Pattern::~Pattern()
+PassRefPtr<SkShader> BitmapPattern::createShader()
 {
-    if (m_externalMemoryAllocated)
-        v8::Isolate::GetCurrent()->AdjustAmountOfExternalAllocatedMemory(-m_externalMemoryAllocated);
-}
-
-SkShader* Pattern::shader()
-{
-    if (m_pattern)
-        return m_pattern.get();
-
     SkMatrix localMatrix = affineTransformToSkMatrix(m_patternSpaceTransformation);
 
+    RefPtr<SkShader> shader;
+
     // If we don't have a bitmap, return a transparent shader.
-    if (!m_tileImage)
-        m_pattern = adoptRef(new SkColorShader(SK_ColorTRANSPARENT));
-    else if (m_repeatX && m_repeatY)
-        m_pattern = adoptRef(SkShader::CreateBitmapShader(m_tileImage->bitmap(), SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode, &localMatrix));
-    else {
+    if (!m_tileImage) {
+        shader = adoptRef(new SkColorShader(SK_ColorTRANSPARENT));
+    } else if (m_repeatX && m_repeatY) {
+        shader = adoptRef(SkShader::CreateBitmapShader(m_tileImage->bitmap(), SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode, &localMatrix));
+    } else {
         // Skia does not have a "draw the tile only once" option. Clamp_TileMode
         // repeats the last line of the image after drawing one tile. To avoid
         // filling the space with arbitrary pixels, this workaround forces the
         // image to have a line of transparent pixels on the "repeated" edge(s),
         // thus causing extra space to be transparent filled.
         SkShader::TileMode tileModeX = m_repeatX ? SkShader::kRepeat_TileMode : SkShader::kClamp_TileMode;
         SkShader::TileMode tileModeY = m_repeatY ? SkShader::kRepeat_TileMode : SkShader::kClamp_TileMode;
         int expandW = m_repeatX ? 0 : 1;
         int expandH = m_repeatY ? 0 : 1;
 
         // Create a transparent bitmap 1 pixel wider and/or taller than the
         // original, then copy the orignal into it.
         // FIXME: Is there a better way to pad (not scale) an image in skia?
         SkImageInfo info = m_tileImage->bitmap().info();
         info.fWidth += expandW;
         info.fHeight += expandH;
         // we explicitly require non-opaquness, since we are going to add a transparent strip.
         info.fAlphaType = kPremul_SkAlphaType;
 
         SkBitmap bm2;
         bm2.allocPixels(info);
         bm2.eraseARGB(0x00, 0x00, 0x00, 0x00);
         SkCanvas canvas(bm2);
         canvas.drawBitmap(m_tileImage->bitmap(), 0, 0);
         bm2.setImmutable();
-        m_pattern = adoptRef(SkShader::CreateBitmapShader(bm2, tileModeX, tileModeY, &localMatrix));
+        shader = adoptRef(SkShader::CreateBitmapShader(bm2, tileModeX, tileModeY, &localMatrix));
 
         // Clamp to int, since that's what the adjust function takes.
-        m_externalMemoryAllocated = static_cast<int>(std::min(static_cast<size_t>(INT_MAX), bm2.getSafeSize()));
+        m_externalMemoryAllocated = static_cast<int> (std::min(static_cast<size_t> (INT_MAX), bm2.getSafeSize()));
         v8::Isolate::GetCurrent()->AdjustAmountOfExternalAllocatedMemory(m_externalMemoryAllocated);
     }
-    return m_pattern.get();
+    return shader;
 }
 
-void Pattern::setPatternSpaceTransform(const AffineTransform& patternSpaceTransformation)
-{
-    m_patternSpaceTransformation = patternSpaceTransformation;
-    if (m_pattern)
-        m_pattern.clear();
-}
-
-}
+} // namespace