FEDisplacementMap.cpp [plain text]
#include "config.h"
#if ENABLE(FILTERS)
#include "FEDisplacementMap.h"
#include "Filter.h"
#include "GraphicsContext.h"
#include "RenderTreeAsText.h"
#include "TextStream.h"
#include <wtf/ByteArray.h>
namespace WebCore {
FEDisplacementMap::FEDisplacementMap(Filter* filter, ChannelSelectorType xChannelSelector, ChannelSelectorType yChannelSelector, float scale)
: FilterEffect(filter)
, m_xChannelSelector(xChannelSelector)
, m_yChannelSelector(yChannelSelector)
, m_scale(scale)
{
}
PassRefPtr<FEDisplacementMap> FEDisplacementMap::create(Filter* filter, ChannelSelectorType xChannelSelector,
ChannelSelectorType yChannelSelector, float scale)
{
return adoptRef(new FEDisplacementMap(filter, xChannelSelector, yChannelSelector, scale));
}
ChannelSelectorType FEDisplacementMap::xChannelSelector() const
{
return m_xChannelSelector;
}
bool FEDisplacementMap::setXChannelSelector(const ChannelSelectorType xChannelSelector)
{
if (m_xChannelSelector == xChannelSelector)
return false;
m_xChannelSelector = xChannelSelector;
return true;
}
ChannelSelectorType FEDisplacementMap::yChannelSelector() const
{
return m_yChannelSelector;
}
bool FEDisplacementMap::setYChannelSelector(const ChannelSelectorType yChannelSelector)
{
if (m_yChannelSelector == yChannelSelector)
return false;
m_yChannelSelector = yChannelSelector;
return true;
}
float FEDisplacementMap::scale() const
{
return m_scale;
}
bool FEDisplacementMap::setScale(float scale)
{
if (m_scale == scale)
return false;
m_scale = scale;
return true;
}
void FEDisplacementMap::apply()
{
if (hasResult())
return;
FilterEffect* in = inputEffect(0);
FilterEffect* in2 = inputEffect(1);
in->apply();
in2->apply();
if (!in->hasResult() || !in2->hasResult())
return;
if (m_xChannelSelector == CHANNEL_UNKNOWN || m_yChannelSelector == CHANNEL_UNKNOWN)
return;
ByteArray* dstPixelArray = createPremultipliedImageResult();
if (!dstPixelArray)
return;
IntRect effectADrawingRect = requestedRegionOfInputImageData(in->absolutePaintRect());
RefPtr<ByteArray> srcPixelArrayA = in->asPremultipliedImage(effectADrawingRect);
IntRect effectBDrawingRect = requestedRegionOfInputImageData(in2->absolutePaintRect());
RefPtr<ByteArray> srcPixelArrayB = in2->asUnmultipliedImage(effectBDrawingRect);
ASSERT(srcPixelArrayA->length() == srcPixelArrayB->length());
Filter* filter = this->filter();
IntSize paintSize = absolutePaintRect().size();
float scaleX = filter->applyHorizontalScale(m_scale / 255);
float scaleY = filter->applyVerticalScale(m_scale / 255);
float scaleAdjustmentX = filter->applyHorizontalScale(0.5f - 0.5f * m_scale);
float scaleAdjustmentY = filter->applyVerticalScale(0.5f - 0.5f * m_scale);
int stride = paintSize.width() * 4;
for (int y = 0; y < paintSize.height(); ++y) {
int line = y * stride;
for (int x = 0; x < paintSize.width(); ++x) {
int dstIndex = line + x * 4;
int srcX = x + static_cast<int>(scaleX * srcPixelArrayB->get(dstIndex + m_xChannelSelector - 1) + scaleAdjustmentX);
int srcY = y + static_cast<int>(scaleY * srcPixelArrayB->get(dstIndex + m_yChannelSelector - 1) + scaleAdjustmentY);
for (unsigned channel = 0; channel < 4; ++channel) {
if (srcX < 0 || srcX >= paintSize.width() || srcY < 0 || srcY >= paintSize.height())
dstPixelArray->set(dstIndex + channel, static_cast<unsigned char>(0));
else {
unsigned char pixelValue = srcPixelArrayA->get(srcY * stride + srcX * 4 + channel);
dstPixelArray->set(dstIndex + channel, pixelValue);
}
}
}
}
}
void FEDisplacementMap::dump()
{
}
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, int indent) const
{
writeIndent(ts, indent);
ts << "[feDisplacementMap";
FilterEffect::externalRepresentation(ts);
ts << " scale=\"" << m_scale << "\" "
<< "xChannelSelector=\"" << m_xChannelSelector << "\" "
<< "yChannelSelector=\"" << m_yChannelSelector << "\"]\n";
inputEffect(0)->externalRepresentation(ts, indent + 1);
inputEffect(1)->externalRepresentation(ts, indent + 1);
return ts;
}
}
#endif // ENABLE(FILTERS)