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Diffstat (limited to 'WebCore/platform/graphics/filters/LightSource.cpp')
| -rw-r--r-- | WebCore/platform/graphics/filters/LightSource.cpp | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/WebCore/platform/graphics/filters/LightSource.cpp b/WebCore/platform/graphics/filters/LightSource.cpp new file mode 100644 index 0000000..a80b14b --- /dev/null +++ b/WebCore/platform/graphics/filters/LightSource.cpp @@ -0,0 +1,169 @@ +/* + * 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) 2010 Zoltan Herczeg <zherczeg@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 + * 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 "LightSource.h" + +#include "DistantLightSource.h" +#include "PointLightSource.h" +#include "RenderTreeAsText.h" +#include "SpotLightSource.h" +#include <wtf/MathExtras.h> + +namespace WebCore { + +void PointLightSource::initPaintingData(PaintingData&) +{ +} + +void PointLightSource::updatePaintingData(PaintingData& paintingData, int x, int y, float z) +{ + paintingData.lightVector.setX(m_position.x() - x); + paintingData.lightVector.setY(m_position.y() - y); + paintingData.lightVector.setZ(m_position.z() - z); + paintingData.lightVector.normalize(); +} + +// spot-light edge darkening depends on an absolute treshold +// according to the SVG 1.1 SE light regression tests +static const float antiAliasTreshold = 0.016f; + +void SpotLightSource::initPaintingData(PaintingData& paintingData) +{ + paintingData.privateColorVector = paintingData.colorVector; + paintingData.directionVector.setX(m_direction.x() - m_position.x()); + paintingData.directionVector.setY(m_direction.y() - m_position.y()); + paintingData.directionVector.setZ(m_direction.z() - m_position.z()); + paintingData.directionVector.normalize(); + + if (!m_limitingConeAngle) { + paintingData.coneCutOffLimit = 0.0f; + paintingData.coneFullLight = -antiAliasTreshold; + } else { + float limitingConeAngle = m_limitingConeAngle; + if (limitingConeAngle < 0.0f) + limitingConeAngle = -limitingConeAngle; + if (limitingConeAngle > 90.0f) + limitingConeAngle = 90.0f; + paintingData.coneCutOffLimit = cosf(deg2rad(180.0f - limitingConeAngle)); + paintingData.coneFullLight = paintingData.coneCutOffLimit - antiAliasTreshold; + } + + // Optimization for common specularExponent values + if (!m_specularExponent) + paintingData.specularExponent = 0; + else if (m_specularExponent == 1.0f) + paintingData.specularExponent = 1; + else // It is neither 0.0f nor 1.0f + paintingData.specularExponent = 2; +} + +void SpotLightSource::updatePaintingData(PaintingData& paintingData, int x, int y, float z) +{ + paintingData.lightVector.setX(m_position.x() - x); + paintingData.lightVector.setY(m_position.y() - y); + paintingData.lightVector.setZ(m_position.z() - z); + paintingData.lightVector.normalize(); + + float cosineOfAngle = paintingData.lightVector * paintingData.directionVector; + if (cosineOfAngle > paintingData.coneCutOffLimit) { + // No light is produced, scanlines are not updated + paintingData.colorVector.setX(0.0f); + paintingData.colorVector.setY(0.0f); + paintingData.colorVector.setZ(0.0f); + return; + } + + // Set the color of the pixel + float lightStrength; + switch (paintingData.specularExponent) { + case 0: + lightStrength = 1.0f; // -cosineOfAngle ^ 0 == 1 + break; + case 1: + lightStrength = -cosineOfAngle; // -cosineOfAngle ^ 1 == -cosineOfAngle + break; + default: + lightStrength = powf(-cosineOfAngle, m_specularExponent); + break; + } + + if (cosineOfAngle > paintingData.coneFullLight) + lightStrength *= (paintingData.coneCutOffLimit - cosineOfAngle) / (paintingData.coneCutOffLimit - paintingData.coneFullLight); + + if (lightStrength > 1.0f) + lightStrength = 1.0f; + + paintingData.colorVector.setX(paintingData.privateColorVector.x() * lightStrength); + paintingData.colorVector.setY(paintingData.privateColorVector.y() * lightStrength); + paintingData.colorVector.setZ(paintingData.privateColorVector.z() * lightStrength); +} + +void DistantLightSource::initPaintingData(PaintingData& paintingData) +{ + float azimuth = deg2rad(m_azimuth); + float elevation = deg2rad(m_elevation); + paintingData.lightVector.setX(cosf(azimuth) * cosf(elevation)); + paintingData.lightVector.setY(sinf(azimuth) * cosf(elevation)); + paintingData.lightVector.setZ(sinf(elevation)); +} + +void DistantLightSource::updatePaintingData(PaintingData&, int, int, float) +{ +} + +static TextStream& operator<<(TextStream& ts, const FloatPoint3D& p) +{ + ts << "x=" << p.x() << " y=" << p.y() << " z=" << p.z(); + return ts; +} + +TextStream& PointLightSource::externalRepresentation(TextStream& ts) const +{ + ts << "[type=POINT-LIGHT] "; + ts << "[position=\"" << position() << "\"]"; + return ts; +} + +TextStream& SpotLightSource::externalRepresentation(TextStream& ts) const +{ + ts << "[type=SPOT-LIGHT] "; + ts << "[position=\"" << position() << "\"]"; + ts << "[direction=\"" << direction() << "\"]"; + ts << "[specularExponent=\"" << specularExponent() << "\"]"; + ts << "[limitingConeAngle=\"" << limitingConeAngle() << "\"]"; + return ts; +} + +TextStream& DistantLightSource::externalRepresentation(TextStream& ts) const +{ + ts << "[type=DISTANT-LIGHT] "; + ts << "[azimuth=\"" << azimuth() << "\"]"; + ts << "[elevation=\"" << elevation() << "\"]"; + return ts; +} + +} // namespace WebCore + +#endif // ENABLE(FILTERS) |