Changeset 53318 in webkit

Timestamp:

Jan 14, 2010 9:10:59 PM (14 years ago)

Author:

mitz@apple.com

Message:

<rdar://problem/6020083> -webkit-gradient slows down scrolling when page has horizontal scrollbar
​https://bugs.webkit.org/show_bug.cgi?id=19650

Reviewed by Simon Fraser.

• platform/graphics/GeneratedImage.cpp:

(WebCore::GeneratedImage::drawPattern): Added call to adjustParametersForTiledDrawing(),
letting the generator substitute the parameters with visually-equivalent values that
are more efficient.

• platform/graphics/Generator.h:

(WebCore::Generator::adjustParametersForTiledDrawing): Added a base class implementation
that does nothing.

• platform/graphics/Gradient.cpp:

(WebCore::Gradient::adjustParametersForTiledDrawing): Added. If the gradient is a horizontal
or vertical linear gradient, changes to use a 1-pixel tall (or wide) tile.

• platform/graphics/Gradient.h:

Location:

trunk/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/GeneratedImage.cpp (modified) (3 diffs)
• platform/graphics/Generator.h (modified) (1 diff)
• platform/graphics/Gradient.cpp (modified) (3 diffs)
• platform/graphics/Gradient.h (modified) (1 diff)

trunk/WebCore/ChangeLog

@@ +1 @@
+2010-01-14  Dan Bernstein  <mitz@apple.com>
+
+        Reviewed by Simon Fraser.
+
+        <rdar://problem/6020083> -webkit-gradient slows down scrolling when page has horizontal scrollbar
+        https://bugs.webkit.org/show_bug.cgi?id=19650
+
+        * platform/graphics/GeneratedImage.cpp:
+        (WebCore::GeneratedImage::drawPattern): Added call to adjustParametersForTiledDrawing(),
+        letting the generator substitute the parameters with visually-equivalent values that
+        are more efficient.
+        * platform/graphics/Generator.h:
+        (WebCore::Generator::adjustParametersForTiledDrawing): Added a base class implementation
+        that does nothing.
+        * platform/graphics/Gradient.cpp:
+        (WebCore::Gradient::adjustParametersForTiledDrawing): Added. If the gradient is a horizontal
+        or vertical linear gradient, changes to use a 1-pixel tall (or wide) tile.
+        * platform/graphics/Gradient.h:
+
 2010-01-14  Norbert Leser  <norbert.leser@nokia.com>
 

trunk/WebCore/platform/graphics/GeneratedImage.cpp

@@ -1 +1 @@
 /*
- * Copyright (C) 2008 Apple Computer, Inc.  All rights reserved.
+ * Copyright (C) 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -11 +11 @@
  *    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. 
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``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 INC. OR ITS 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.
  */
 
@@ -51 +51 @@
                                  const FloatPoint& phase, ColorSpace styleColorSpace, CompositeOperator compositeOp, const FloatRect& destRect)
 {
+    // Allow the generator to provide visually-equivalent tiling parameters for better performance.
+    IntSize adjustedSize = m_size;
+    FloatRect adjustedSrcRect = srcRect;
+    m_generator->adjustParametersForTiledDrawing(adjustedSize, adjustedSrcRect);
+
     // Create a BitmapImage and call drawPattern on it.
-    OwnPtr<ImageBuffer> imageBuffer = ImageBuffer::create(m_size);
+    OwnPtr<ImageBuffer> imageBuffer = ImageBuffer::create(adjustedSize);
     ASSERT(imageBuffer.get());
-    
+
     // Fill with the gradient.
     GraphicsContext* graphicsContext = imageBuffer->context();
-    graphicsContext->fillRect(FloatRect(FloatPoint(), m_size), *m_generator.get());
-    
+    graphicsContext->fillRect(FloatRect(FloatPoint(), adjustedSize), *m_generator.get());
+
     // Grab the final image from the image buffer.
     Image* bitmap = imageBuffer->image();
-    
+
     // Now just call drawTiled on that image.
-    bitmap->drawPattern(context, srcRect, patternTransform, phase, styleColorSpace, compositeOp, destRect);
+    bitmap->drawPattern(context, adjustedSrcRect, patternTransform, phase, styleColorSpace, compositeOp, destRect);
 }
 

trunk/WebCore/platform/graphics/Generator.h

@@ -39 +39 @@
     
     virtual void fill(GraphicsContext*, const FloatRect&) = 0;
+    virtual void adjustParametersForTiledDrawing(IntSize& /* size */, FloatRect& /* srcRect */) { }
 };
 

trunk/WebCore/platform/graphics/Gradient.cpp

@@ -1 +1 @@
 /*
- * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
+ * Copyright (C) 2006, 2007, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  *
@@ -29 +29 @@
 
 #include "Color.h"
+#include "FloatRect.h"
+#include <wtf/UnusedParam.h>
 
 namespace WebCore {
@@ -61 +63 @@
 {
     platformDestroy();
+}
+
+void Gradient::adjustParametersForTiledDrawing(IntSize& size, FloatRect& srcRect)
+{
+    if (m_radial)
+        return;
+
+    if (srcRect.isEmpty())
+        return;
+
+    if (m_p0.x() == m_p1.x()) {
+        size.setWidth(1);
+        srcRect.setWidth(1);
+        srcRect.setX(0);
+        return;
+    }
+    if (m_p0.y() != m_p1.y())
+        return;
+
+    size.setHeight(1);
+    srcRect.setHeight(1);
+    srcRect.setY(0);
 }
 

trunk/WebCore/platform/graphics/Gradient.h

@@ -106 +106 @@
 
         virtual void fill(GraphicsContext*, const FloatRect&);
+        virtual void adjustParametersForTiledDrawing(IntSize& size, FloatRect& srcRect);
+
         void setPlatformGradientSpaceTransform(const TransformationMatrix& gradientSpaceTransformation);