FEDisplacementMap.cpp [plain text]
#include "config.h"
#include "FEDisplacementMap.h"
#include "ColorUtilities.h"
#include "Filter.h"
#include "GraphicsContext.h"
#include <JavaScriptCore/Uint8ClampedArray.h>
#include <wtf/text/TextStream.h>
namespace WebCore {
FEDisplacementMap::FEDisplacementMap(Filter& filter, ChannelSelectorType xChannelSelector, ChannelSelectorType yChannelSelector, float scale)
: FilterEffect(filter)
, m_xChannelSelector(xChannelSelector)
, m_yChannelSelector(yChannelSelector)
, m_scale(scale)
{
}
Ref<FEDisplacementMap> FEDisplacementMap::create(Filter& filter, ChannelSelectorType xChannelSelector,
ChannelSelectorType yChannelSelector, float scale)
{
return adoptRef(*new FEDisplacementMap(filter, xChannelSelector, yChannelSelector, scale));
}
bool FEDisplacementMap::setXChannelSelector(const ChannelSelectorType xChannelSelector)
{
if (m_xChannelSelector == xChannelSelector)
return false;
m_xChannelSelector = xChannelSelector;
return true;
}
bool FEDisplacementMap::setYChannelSelector(const ChannelSelectorType yChannelSelector)
{
if (m_yChannelSelector == yChannelSelector)
return false;
m_yChannelSelector = yChannelSelector;
return true;
}
bool FEDisplacementMap::setScale(float scale)
{
if (m_scale == scale)
return false;
m_scale = scale;
return true;
}
void FEDisplacementMap::setResultColorSpace(ColorSpace)
{
FilterEffect::setResultColorSpace(inputEffect(0)->resultColorSpace());
}
void FEDisplacementMap::transformResultColorSpace(FilterEffect* in, const int index)
{
if (index)
in->transformResultColorSpace(operatingColorSpace());
}
void FEDisplacementMap::platformApplySoftware()
{
FilterEffect* in = inputEffect(0);
FilterEffect* in2 = inputEffect(1);
ASSERT(m_xChannelSelector != CHANNEL_UNKNOWN);
ASSERT(m_yChannelSelector != CHANNEL_UNKNOWN);
Uint8ClampedArray* dstPixelArray = createPremultipliedImageResult();
if (!dstPixelArray)
return;
IntRect effectADrawingRect = requestedRegionOfInputImageData(in->absolutePaintRect());
auto inputImage = in->premultipliedResult(effectADrawingRect);
IntRect effectBDrawingRect = requestedRegionOfInputImageData(in2->absolutePaintRect());
auto displacementImage = in2->unmultipliedResult(effectBDrawingRect);
if (!inputImage || !displacementImage)
return;
ASSERT(inputImage->length() == displacementImage->length());
Filter& filter = this->filter();
IntSize paintSize = absolutePaintRect().size();
paintSize.scale(filter.filterScale());
FloatSize scale = filter.scaledByFilterResolution({ m_scale, m_scale });
float scaleForColorX = scale.width() / 255.0;
float scaleForColorY = scale.height() / 255.0;
float scaledOffsetX = 0.5 - scale.width() * 0.5;
float scaledOffsetY = 0.5 - scale.height() * 0.5;
int displacementChannelX = xChannelIndex();
int displacementChannelY = yChannelIndex();
int rowBytes = paintSize.width() * 4;
for (int y = 0; y < paintSize.height(); ++y) {
int lineStartOffset = y * rowBytes;
for (int x = 0; x < paintSize.width(); ++x) {
int dstIndex = lineStartOffset + x * 4;
int srcX = x + static_cast<int>(scaleForColorX * displacementImage->item(dstIndex + displacementChannelX) + scaledOffsetX);
int srcY = y + static_cast<int>(scaleForColorY * displacementImage->item(dstIndex + displacementChannelY) + scaledOffsetY);
unsigned* dstPixelPtr = reinterpret_cast<unsigned*>(dstPixelArray->data() + dstIndex);
if (srcX < 0 || srcX >= paintSize.width() || srcY < 0 || srcY >= paintSize.height()) {
*dstPixelPtr = 0;
continue;
}
*dstPixelPtr = *reinterpret_cast<unsigned*>(inputImage->data() + byteOffsetOfPixel(srcX, srcY, rowBytes));
}
}
}
static TextStream& operator<<(TextStream& ts, const ChannelSelectorType& type)
{
switch (type) {
case CHANNEL_UNKNOWN:
ts << "UNKNOWN";
break;
case CHANNEL_R:
ts << "RED";
break;
case CHANNEL_G:
ts << "GREEN";
break;
case CHANNEL_B:
ts << "BLUE";
break;
case CHANNEL_A:
ts << "ALPHA";
break;
}
return ts;
}
TextStream& FEDisplacementMap::externalRepresentation(TextStream& ts, RepresentationType representation) const
{
ts << indent << "[feDisplacementMap";
FilterEffect::externalRepresentation(ts, representation);
ts << " scale=\"" << m_scale << "\" "
<< "xChannelSelector=\"" << m_xChannelSelector << "\" "
<< "yChannelSelector=\"" << m_yChannelSelector << "\"]\n";
TextStream::IndentScope indentScope(ts);
inputEffect(0)->externalRepresentation(ts, representation);
inputEffect(1)->externalRepresentation(ts, representation);
return ts;
}
}