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Diffstat (limited to 'Source/WebCore/platform/graphics/filters/FEComponentTransfer.cpp')
-rw-r--r-- | Source/WebCore/platform/graphics/filters/FEComponentTransfer.cpp | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/Source/WebCore/platform/graphics/filters/FEComponentTransfer.cpp b/Source/WebCore/platform/graphics/filters/FEComponentTransfer.cpp new file mode 100644 index 0000000..ca8e5d3 --- /dev/null +++ b/Source/WebCore/platform/graphics/filters/FEComponentTransfer.cpp @@ -0,0 +1,245 @@ +/* + * Copyright (C) 2004, 2005, 2006, 2007 Nikolas Zimmermann <zimmermann@kde.org> + * Copyright (C) 2004, 2005 Rob Buis <buis@kde.org> + * Copyright (C) 2005 Eric Seidel <eric@webkit.org> + * Copyright (C) 2009 Dirk Schulze <krit@webkit.org> + * Copyright (C) Research In Motion Limited 2010. All rights reserved. + * + * 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 + * along 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 "FEComponentTransfer.h" + +#include "Filter.h" +#include "GraphicsContext.h" + +#include <wtf/ByteArray.h> +#include <wtf/MathExtras.h> + +namespace WebCore { + +typedef void (*TransferType)(unsigned char*, const ComponentTransferFunction&); + +FEComponentTransfer::FEComponentTransfer(Filter* filter, const ComponentTransferFunction& redFunc, const ComponentTransferFunction& greenFunc, + const ComponentTransferFunction& blueFunc, const ComponentTransferFunction& alphaFunc) + : FilterEffect(filter) + , m_redFunc(redFunc) + , m_greenFunc(greenFunc) + , m_blueFunc(blueFunc) + , m_alphaFunc(alphaFunc) +{ +} + +PassRefPtr<FEComponentTransfer> FEComponentTransfer::create(Filter* filter, const ComponentTransferFunction& redFunc, + const ComponentTransferFunction& greenFunc, const ComponentTransferFunction& blueFunc, const ComponentTransferFunction& alphaFunc) +{ + return adoptRef(new FEComponentTransfer(filter, redFunc, greenFunc, blueFunc, alphaFunc)); +} + +ComponentTransferFunction FEComponentTransfer::redFunction() const +{ + return m_redFunc; +} + +void FEComponentTransfer::setRedFunction(const ComponentTransferFunction& func) +{ + m_redFunc = func; +} + +ComponentTransferFunction FEComponentTransfer::greenFunction() const +{ + return m_greenFunc; +} + +void FEComponentTransfer::setGreenFunction(const ComponentTransferFunction& func) +{ + m_greenFunc = func; +} + +ComponentTransferFunction FEComponentTransfer::blueFunction() const +{ + return m_blueFunc; +} + +void FEComponentTransfer::setBlueFunction(const ComponentTransferFunction& func) +{ + m_blueFunc = func; +} + +ComponentTransferFunction FEComponentTransfer::alphaFunction() const +{ + return m_alphaFunc; +} + +void FEComponentTransfer::setAlphaFunction(const ComponentTransferFunction& func) +{ + m_alphaFunc = func; +} + +static void identity(unsigned char*, const ComponentTransferFunction&) +{ +} + +static void table(unsigned char* values, const ComponentTransferFunction& transferFunction) +{ + const Vector<float>& tableValues = transferFunction.tableValues; + unsigned n = tableValues.size(); + if (n < 1) + return; + for (unsigned i = 0; i < 256; ++i) { + double c = i / 255.0; + unsigned k = static_cast<unsigned>(c * (n - 1)); + double v1 = tableValues[k]; + double v2 = tableValues[std::min((k + 1), (n - 1))]; + double val = 255.0 * (v1 + (c * (n - 1) - k) * (v2 - v1)); + val = std::max(0.0, std::min(255.0, val)); + values[i] = static_cast<unsigned char>(val); + } +} + +static void discrete(unsigned char* values, const ComponentTransferFunction& transferFunction) +{ + const Vector<float>& tableValues = transferFunction.tableValues; + unsigned n = tableValues.size(); + if (n < 1) + return; + for (unsigned i = 0; i < 256; ++i) { + unsigned k = static_cast<unsigned>((i * n) / 255.0); + k = std::min(k, n - 1); + double val = 255 * tableValues[k]; + val = std::max(0.0, std::min(255.0, val)); + values[i] = static_cast<unsigned char>(val); + } +} + +static void linear(unsigned char* values, const ComponentTransferFunction& transferFunction) +{ + for (unsigned i = 0; i < 256; ++i) { + double val = transferFunction.slope * i + 255 * transferFunction.intercept; + val = std::max(0.0, std::min(255.0, val)); + values[i] = static_cast<unsigned char>(val); + } +} + +static void gamma(unsigned char* values, const ComponentTransferFunction& transferFunction) +{ + for (unsigned i = 0; i < 256; ++i) { + double exponent = transferFunction.exponent; // RCVT doesn't like passing a double and a float to pow, so promote this to double + double val = 255.0 * (transferFunction.amplitude * pow((i / 255.0), exponent) + transferFunction.offset); + val = std::max(0.0, std::min(255.0, val)); + values[i] = static_cast<unsigned char>(val); + } +} + +void FEComponentTransfer::apply() +{ + if (hasResult()) + return; + FilterEffect* in = inputEffect(0); + in->apply(); + if (!in->hasResult()) + return; + + ByteArray* pixelArray = createUnmultipliedImageResult(); + if (!pixelArray) + return; + + unsigned char rValues[256], gValues[256], bValues[256], aValues[256]; + for (unsigned i = 0; i < 256; ++i) + rValues[i] = gValues[i] = bValues[i] = aValues[i] = i; + unsigned char* tables[] = { rValues, gValues, bValues, aValues }; + ComponentTransferFunction transferFunction[] = {m_redFunc, m_greenFunc, m_blueFunc, m_alphaFunc}; + TransferType callEffect[] = {identity, identity, table, discrete, linear, gamma}; + + for (unsigned channel = 0; channel < 4; channel++) + (*callEffect[transferFunction[channel].type])(tables[channel], transferFunction[channel]); + + IntRect drawingRect = requestedRegionOfInputImageData(in->absolutePaintRect()); + in->copyUnmultipliedImage(pixelArray, drawingRect); + + unsigned pixelArrayLength = pixelArray->length(); + for (unsigned pixelOffset = 0; pixelOffset < pixelArrayLength; pixelOffset += 4) { + for (unsigned channel = 0; channel < 4; ++channel) { + unsigned char c = pixelArray->get(pixelOffset + channel); + pixelArray->set(pixelOffset + channel, tables[channel][c]); + } + } +} + +void FEComponentTransfer::dump() +{ +} + +static TextStream& operator<<(TextStream& ts, const ComponentTransferType& type) +{ + switch (type) { + case FECOMPONENTTRANSFER_TYPE_UNKNOWN: + ts << "UNKNOWN"; + break; + case FECOMPONENTTRANSFER_TYPE_IDENTITY: + ts << "IDENTITY"; + break; + case FECOMPONENTTRANSFER_TYPE_TABLE: + ts << "TABLE"; + break; + case FECOMPONENTTRANSFER_TYPE_DISCRETE: + ts << "DISCRETE"; + break; + case FECOMPONENTTRANSFER_TYPE_LINEAR: + ts << "LINEAR"; + break; + case FECOMPONENTTRANSFER_TYPE_GAMMA: + ts << "GAMMA"; + break; + } + return ts; +} + +static TextStream& operator<<(TextStream& ts, const ComponentTransferFunction& function) +{ + ts << "type=\"" << function.type + << "\" slope=\"" << function.slope + << "\" intercept=\"" << function.intercept + << "\" amplitude=\"" << function.amplitude + << "\" exponent=\"" << function.exponent + << "\" offset=\"" << function.offset << "\""; + return ts; +} + +TextStream& FEComponentTransfer::externalRepresentation(TextStream& ts, int indent) const +{ + writeIndent(ts, indent); + ts << "[feComponentTransfer"; + FilterEffect::externalRepresentation(ts); + ts << " \n"; + writeIndent(ts, indent + 2); + ts << "{red: " << m_redFunc << "}\n"; + writeIndent(ts, indent + 2); + ts << "{green: " << m_greenFunc << "}\n"; + writeIndent(ts, indent + 2); + ts << "{blue: " << m_blueFunc << "}\n"; + writeIndent(ts, indent + 2); + ts << "{alpha: " << m_alphaFunc << "}]\n"; + inputEffect(0)->externalRepresentation(ts, indent + 1); + return ts; +} + +} // namespace WebCore + +#endif // ENABLE(FILTERS) |