| /* |
| * Copyright (C) 2008 Alex Mathews <possessedpenguinbob@gmail.com> |
| * 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> |
| * Copyright (C) 2011 University of Szeged |
| * Copyright (C) 2011 Renata Hodovan <reni@webkit.org> |
| * Copyright (C) 2021-2022 Apple Inc. All rights reserved. |
| * |
| * 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 "SpotLightSource.h" |
| |
| #include "Filter.h" |
| #include "FilterImage.h" |
| #include <wtf/text/TextStream.h> |
| |
| namespace WebCore { |
| |
| // spot-light edge darkening depends on an absolute treshold |
| // according to the SVG 1.1 SE light regression tests |
| static const float antialiasThreshold = 0.016f; |
| |
| Ref<SpotLightSource> SpotLightSource::create(const FloatPoint3D& position, const FloatPoint3D& direction, float specularExponent, float limitingConeAngle) |
| { |
| return adoptRef(*new SpotLightSource(position, direction, specularExponent, limitingConeAngle)); |
| } |
| |
| SpotLightSource::SpotLightSource(const FloatPoint3D& position, const FloatPoint3D& pointsAt, float specularExponent, float limitingConeAngle) |
| : LightSource(LS_SPOT) |
| , m_position(position) |
| , m_pointsAt(pointsAt) |
| , m_specularExponent(specularExponent) |
| , m_limitingConeAngle(limitingConeAngle) |
| { |
| } |
| |
| void SpotLightSource::initPaintingData(const Filter& filter, const FilterImage& result, PaintingData& paintingData) const |
| { |
| auto position = filter.resolvedPoint3D(m_position); |
| auto pointsAt = filter.resolvedPoint3D(m_pointsAt); |
| |
| auto absolutePosition = filter.scaledByFilterScale(position.xy()); |
| m_bufferPosition.setXY(result.mappedAbsolutePoint(absolutePosition)); |
| |
| // To scale Z, map a point offset from position in the x direction by z. |
| auto absoluteMappedZ = filter.scaledByFilterScale(FloatPoint { position.x() + position.z(), position.y() }); |
| m_bufferPosition.setZ(result.mappedAbsolutePoint(absoluteMappedZ).x() - m_bufferPosition.x()); |
| |
| paintingData.directionVector = pointsAt - position; |
| paintingData.directionVector.normalize(); |
| |
| if (!m_limitingConeAngle) { |
| paintingData.coneCutOffLimit = 0.0f; |
| paintingData.coneFullLight = -antialiasThreshold; |
| } 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 - antialiasThreshold; |
| } |
| |
| // 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; |
| } |
| |
| LightSource::ComputedLightingData SpotLightSource::computePixelLightingData(const PaintingData& paintingData, int x, int y, float z) const |
| { |
| FloatPoint3D lightVector = { |
| m_bufferPosition.x() - x, |
| m_bufferPosition.y() - y, |
| m_bufferPosition.z() - z |
| }; |
| float lightVectorLength = lightVector.length(); |
| |
| float cosineOfAngle = (lightVector * paintingData.directionVector) / lightVectorLength; |
| if (cosineOfAngle > paintingData.coneCutOffLimit) { |
| // No light is produced, scanlines are not updated |
| return { lightVector, { }, lightVectorLength }; |
| } |
| |
| // 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; |
| |
| return { |
| lightVector, |
| paintingData.initialLightingData.colorVector * lightStrength, |
| lightVectorLength |
| }; |
| } |
| |
| bool SpotLightSource::setX(float x) |
| { |
| if (m_position.x() == x) |
| return false; |
| m_position.setX(x); |
| return true; |
| } |
| |
| bool SpotLightSource::setY(float y) |
| { |
| if (m_position.y() == y) |
| return false; |
| m_position.setY(y); |
| return true; |
| } |
| |
| bool SpotLightSource::setZ(float z) |
| { |
| if (m_position.z() == z) |
| return false; |
| m_position.setZ(z); |
| return true; |
| } |
| |
| bool SpotLightSource::setPointsAtX(float pointsAtX) |
| { |
| if (m_pointsAt.x() == pointsAtX) |
| return false; |
| m_pointsAt.setX(pointsAtX); |
| return true; |
| } |
| |
| bool SpotLightSource::setPointsAtY(float pointsAtY) |
| { |
| if (m_pointsAt.y() == pointsAtY) |
| return false; |
| m_pointsAt.setY(pointsAtY); |
| return true; |
| } |
| |
| bool SpotLightSource::setPointsAtZ(float pointsAtZ) |
| { |
| if (m_pointsAt.z() == pointsAtZ) |
| return false; |
| m_pointsAt.setZ(pointsAtZ); |
| return true; |
| } |
| |
| bool SpotLightSource::setSpecularExponent(float specularExponent) |
| { |
| if (m_specularExponent == specularExponent) |
| return false; |
| m_specularExponent = specularExponent; |
| return true; |
| } |
| |
| bool SpotLightSource::setLimitingConeAngle(float limitingConeAngle) |
| { |
| if (m_limitingConeAngle == limitingConeAngle) |
| return false; |
| m_limitingConeAngle = limitingConeAngle; |
| return true; |
| } |
| |
| TextStream& SpotLightSource::externalRepresentation(TextStream& ts) const |
| { |
| ts << "[type=SPOT-LIGHT] "; |
| ts << "[position=\"" << position() << "\"]"; |
| ts << "[direction=\"" << direction() << "\"]"; |
| ts << "[specularExponent=\"" << specularExponent() << "\"]"; |
| ts << "[limitingConeAngle=\"" << limitingConeAngle() << "\"]"; |
| return ts; |
| } |
| |
| }; // namespace WebCore |