1 files changed, 140 insertions, 0 deletions
diff --git a/WebCore/platform/graphics/filters/FEGaussianBlur.cpp b/WebCore/platform/graphics/filters/FEGaussianBlur.cpp
new file mode 100644
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+++ b/WebCore/platform/graphics/filters/FEGaussianBlur.cpp
@@ -0,0 +1,140 @@
+/*
+    Copyright (C) 2004, 2005, 2006, 2007 Nikolas Zimmermann <zimmermann@kde.org>
+                  2004, 2005 Rob Buis <buis@kde.org>
+                  2005 Eric Seidel <eric@webkit.org>
+                  2009 Dirk Schulze <krit@webkit.org>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    aint with this library; see the file COPYING.LIB.  If not, write to
+    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+    Boston, MA 02110-1301, USA.
+*/
+
+#include "config.h"
+
+#if ENABLE(FILTERS)
+#include "FEGaussianBlur.h"
+
+#include "CanvasPixelArray.h"
+#include "Filter.h"
+#include "GraphicsContext.h"
+#include "ImageData.h"
+#include <math.h>
+#include <wtf/MathExtras.h>
+
+namespace WebCore {
+
+FEGaussianBlur::FEGaussianBlur(FilterEffect* in, const float& x, const float& y)
+    : FilterEffect()
+    , m_in(in)
+    , m_x(x)
+    , m_y(y)
+{
+}
+
+PassRefPtr<FEGaussianBlur> FEGaussianBlur::create(FilterEffect* in, const float& x, const float& y)
+{
+    return adoptRef(new FEGaussianBlur(in, x, y));
+}
+
+float FEGaussianBlur::stdDeviationX() const
+{
+    return m_x;
+}
+
+void FEGaussianBlur::setStdDeviationX(float x)
+{
+    m_x = x;
+}
+
+float FEGaussianBlur::stdDeviationY() const
+{
+    return m_y;
+}
+
+void FEGaussianBlur::setStdDeviationY(float y)
+{
+    m_y = y;
+}
+
+static void boxBlur(CanvasPixelArray*& srcPixelArray, CanvasPixelArray*& dstPixelArray,
+                 unsigned dx, int stride, int strideLine, int effectWidth, int effectHeight, bool alphaImage)
+{
+    int dxLeft = dx / 2;
+    int dxRight = dx - dxLeft;
+
+    for (int y = 0; y < effectHeight; ++y) {
+        int line = y * strideLine;
+        for (int channel = 3; channel >= 0; --channel) {
+            int sum = 0;
+            // Fill the kernel
+            int maxKernelSize = std::min(dxRight, effectWidth);
+            for (int i = 0; i < maxKernelSize; ++i)
+                sum += srcPixelArray->get(line + i * stride + channel);
+
+            // Blurring
+            for (int x = 0; x < effectWidth; ++x) {
+                int pixelByteOffset = line + x * stride + channel;
+                dstPixelArray->set(pixelByteOffset, static_cast<unsigned char>(sum / dx));
+                if (x >= dxLeft)
+                    sum -= srcPixelArray->get(pixelByteOffset - dxLeft * stride);
+                if (x + dxRight < effectWidth)
+                    sum += srcPixelArray->get(pixelByteOffset + dxRight * stride);
+            }
+            if (alphaImage) // Source image is black, it just has different alpha values
+                break;
+        }
+    }
+}
+
+void FEGaussianBlur::apply(Filter* filter)
+{
+    m_in->apply(filter);
+    if (!m_in->resultImage())
+        return;
+
+    if (!getEffectContext())
+        return;
+
+    setIsAlphaImage(m_in->isAlphaImage());
+
+    if (m_x == 0 || m_y == 0)
+        return;
+
+    unsigned sdx = static_cast<unsigned>(floor(m_x * 3 * sqrt(2 * piDouble) / 4.f + 0.5f));
+    unsigned sdy = static_cast<unsigned>(floor(m_y * 3 * sqrt(2 * piDouble) / 4.f + 0.5f));
+
+    IntRect effectDrawingRect = calculateDrawingIntRect(m_in->subRegion());
+    RefPtr<ImageData> srcImageData(m_in->resultImage()->getPremultipliedImageData(effectDrawingRect));
+    CanvasPixelArray* srcPixelArray(srcImageData->data());
+
+    IntRect imageRect(IntPoint(), resultImage()->size());
+    RefPtr<ImageData> tmpImageData = ImageData::create(imageRect.width(), imageRect.height());
+    CanvasPixelArray* tmpPixelArray(tmpImageData->data());
+
+    int stride = 4 * imageRect.width();
+    for (int i = 0; i < 3; ++i) {
+        boxBlur(srcPixelArray, tmpPixelArray, sdx, 4, stride, imageRect.width(), imageRect.height(), isAlphaImage());
+        boxBlur(tmpPixelArray, srcPixelArray, sdy, stride, 4, imageRect.height(), imageRect.width(), isAlphaImage());
+    }
+
+    resultImage()->putPremultipliedImageData(srcImageData.get(), imageRect, IntPoint());
+}
+
+void FEGaussianBlur::dump()
+{
+}
+
+} // namespace WebCore
+
+#endif // ENABLE(FILTERS)