WebCore/css/CSSGradientValue.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/css/CSSGradientValue.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2008 Apple 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 "CSSGradientValue.h"
+
+#include "CSSStyleSelector.h"
+#include "GeneratedImage.h"
+#include "Gradient.h"
+#include "Image.h"
+#include "IntSize.h"
+#include "IntSizeHash.h"
+#include "PlatformString.h"
+#include "RenderObject.h"
+
+using namespace std;
+
+namespace WebCore {
+
+String CSSGradientValue::cssText() const
+{
+    String result = "-webkit-gradient(";
+    if (m_type == CSSLinearGradient)
+        result += "linear, ";
+    else
+        result += "radial, ";
+    result += m_firstX->cssText() + " ";
+    result += m_firstY->cssText() + ", ";
+    if (m_type == CSSRadialGradient)
+        result += m_firstRadius->cssText() + ", ";
+    result += m_secondX->cssText() + " ";
+    result += m_secondY->cssText();
+    if (m_type == CSSRadialGradient) {
+        result += ", ";
+        result += m_secondRadius->cssText();
+    }
+    for (unsigned i = 0; i < m_stops.size(); i++) {
+        result += ", ";
+        if (m_stops[i].m_stop == 0)
+            result += "from(" + m_stops[i].m_color->cssText() + ")";
+        else if (m_stops[i].m_stop == 1)
+            result += "to(" + m_stops[i].m_color->cssText() + ")";
+        else
+            result += "color-stop(" + String::number(m_stops[i].m_stop) + ", " + m_stops[i].m_color->cssText() + ")";
+    }
+    result += ")";
+    return result;
+}
+
+PassRefPtr<Gradient> CSSGradientValue::createGradient(RenderObject* renderer, const IntSize& size)
+{
+    ASSERT(!size.isEmpty());
+    
+    float zoomFactor = renderer->style()->effectiveZoom();
+    
+    FloatPoint firstPoint = resolvePoint(m_firstX.get(), m_firstY.get(), size, zoomFactor);
+    FloatPoint secondPoint = resolvePoint(m_secondX.get(), m_secondY.get(), size, zoomFactor);
+    
+    RefPtr<Gradient> gradient;
+    if (m_type == CSSLinearGradient)
+        gradient = Gradient::create(firstPoint, secondPoint);
+    else {
+        float firstRadius = resolveRadius(m_firstRadius.get(), zoomFactor);
+        float secondRadius = resolveRadius(m_secondRadius.get(), zoomFactor);
+        gradient = Gradient::create(firstPoint, firstRadius, secondPoint, secondRadius);
+    }
+
+    // Now add the stops.
+    sortStopsIfNeeded();
+
+    // We have to resolve colors.
+    for (unsigned i = 0; i < m_stops.size(); i++) {
+        Color color = renderer->document()->styleSelector()->getColorFromPrimitiveValue(m_stops[i].m_color.get());
+        gradient->addColorStop(m_stops[i].m_stop, color);
+    }
+
+    // The back end already sorted the stops.
+    gradient->setStopsSorted(true);
+
+    return gradient.release();
+}
+
+Image* CSSGradientValue::image(RenderObject* renderer, const IntSize& size)
+{
+    ASSERT(m_clients.contains(renderer));
+
+    // Need to look up our size.  Create a string of width*height to use as a hash key.
+    Image* result = getImage(renderer, size);
+    if (result)
+        return result;
+
+    if (size.isEmpty())
+        return 0;
+
+    // We need to create an image.
+    RefPtr<Image> newImage = GeneratedImage::create(createGradient(renderer, size), size);
+    result = newImage.get();
+    putImage(size, newImage.release());
+
+    return result;
+}
+
+static inline bool compareStops(const CSSGradientColorStop& a, const CSSGradientColorStop& b)
+{
+    return a.m_stop < b.m_stop;
+}
+
+void CSSGradientValue::sortStopsIfNeeded()
+{
+    if (!m_stopsSorted) {
+        if (m_stops.size())
+            std::stable_sort(m_stops.begin(), m_stops.end(), compareStops);
+        m_stopsSorted = true;
+    }
+}
+
+FloatPoint CSSGradientValue::resolvePoint(CSSPrimitiveValue* first, CSSPrimitiveValue* second, const IntSize& size, float zoomFactor)
+{
+    FloatPoint result;
+    if (first->primitiveType() == CSSPrimitiveValue::CSS_NUMBER)
+        result.setX(first->getFloatValue() * zoomFactor);
+    else if (first->primitiveType() == CSSPrimitiveValue::CSS_PERCENTAGE)
+        result.setX(first->getFloatValue() / 100.f * size.width());
+    if (second->primitiveType() == CSSPrimitiveValue::CSS_NUMBER)
+        result.setY(second->getFloatValue() * zoomFactor);
+    else if (second->primitiveType() == CSSPrimitiveValue::CSS_PERCENTAGE)
+        result.setY(second->getFloatValue() / 100.f * size.height());
+
+    return result;
+}
+
+float CSSGradientValue::resolveRadius(CSSPrimitiveValue* radius, float zoomFactor)
+{
+    float result = 0.f;
+    if (radius->primitiveType() == CSSPrimitiveValue::CSS_NUMBER)
+        result = radius->getFloatValue() * zoomFactor;
+    return result;
+}
+
+} // namespace WebCore