Source/core/rendering/svg/RenderSVGResourceFilterPrimitive.cpp

/*
 * Copyright (C) 2010 University of Szeged
 * Copyright (C) 2010 Zoltan Herczeg
 * Copyright (C) 2011 Renata Hodovan (reni@webkit.org)
 *
 * 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 UNIVERSITY OF SZEGED ``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 UNIVERSITY OF SZEGED 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 "core/rendering/svg/RenderSVGResourceFilterPrimitive.h"

namespace WebCore {

void RenderSVGResourceFilterPrimitive::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
{
    RenderSVGHiddenContainer::styleDidChange(diff, oldStyle);

    RenderObject* filter = parent();
    if (!filter)
        return;
    ASSERT(filter->isSVGResourceFilter());

    if (diff == StyleDifferenceEqual || !oldStyle)
        return;

    const SVGRenderStyle* newStyle = this->style()->svgStyle();
    if (element()->hasTagName(SVGNames::feFloodTag)) {
        if (newStyle->floodColor() != oldStyle->svgStyle()->floodColor())
            toRenderSVGFilter(filter)->primitiveAttributeChanged(this, SVGNames::flood_colorAttr);
        if (newStyle->floodOpacity() != oldStyle->svgStyle()->floodOpacity())
            toRenderSVGFilter(filter)->primitiveAttributeChanged(this, SVGNames::flood_opacityAttr);
    } else if (element()->hasTagName(SVGNames::feDiffuseLightingTag) || element()->hasTagName(SVGNames::feSpecularLightingTag)) {
        if (newStyle->lightingColor() != oldStyle->svgStyle()->lightingColor())
            toRenderSVGFilter(filter)->primitiveAttributeChanged(this, SVGNames::lighting_colorAttr);
    }
}

FloatRect RenderSVGResourceFilterPrimitive::determineFilterPrimitiveSubregion(FilterEffect* effect)
{
    SVGFilter* filter = static_cast<SVGFilter*>(effect->filter());
    ASSERT(filter);

    // FETile, FETurbulence, FEFlood don't have input effects, take the filter region as unite rect.
    FloatRect subregion;
    if (unsigned numberOfInputEffects = effect->inputEffects().size()) {
        subregion = determineFilterPrimitiveSubregion(effect->inputEffect(0));
        for (unsigned i = 1; i < numberOfInputEffects; ++i)
            subregion.unite(determineFilterPrimitiveSubregion(effect->inputEffect(i)));
    } else
        subregion = filter->filterRegion();

    // After calling determineFilterPrimitiveSubregion on the target effect, reset the subregion again for <feTile>.
    if (effect->filterEffectType() == FilterEffectTypeTile)
        subregion = filter->filterRegion();

    FloatRect effectBoundaries = effect->effectBoundaries();
    if (effect->hasX())
        subregion.setX(effectBoundaries.x());
    if (effect->hasY())
        subregion.setY(effectBoundaries.y());
    if (effect->hasWidth())
        subregion.setWidth(effectBoundaries.width());
    if (effect->hasHeight())
        subregion.setHeight(effectBoundaries.height());

    effect->setFilterPrimitiveSubregion(subregion);

    FloatRect absoluteSubregion = filter->absoluteTransform().mapRect(subregion);
    FloatSize filterResolution = filter->filterResolution();
    absoluteSubregion.scale(filterResolution.width(), filterResolution.height());

    // Clip every filter effect to the filter region.
    FloatRect absoluteScaledFilterRegion = filter->absoluteFilterRegion();
    absoluteScaledFilterRegion.scale(filterResolution.width(), filterResolution.height());
    absoluteSubregion.intersect(absoluteScaledFilterRegion);

    effect->setMaxEffectRect(absoluteSubregion);
    return subregion;
}

} // namespace WebCore