/*
* 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>
*
* 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.
*/
#ifndef LightSource_h
#define LightSource_h
#include "platform/PlatformExport.h"
#include "platform/geometry/FloatPoint3D.h"
#include "wtf/PassRefPtr.h"
#include "wtf/RefCounted.h"
namespace WebCore {
enum LightType {
LS_DISTANT,
LS_POINT,
LS_SPOT
};
class TextStream;
class PLATFORM_EXPORT LightSource : public RefCounted<LightSource> {
public:
// Light vectors must be calculated for every pixel during
// painting. It is expensive to pass all these arguments to
// a frequently called function, especially because not all
// light sources require all of them. Instead, we just pass
// a reference to the following structure
struct PaintingData {
// SVGFELighting also use them
FloatPoint3D lightVector;
FloatPoint3D colorVector;
float lightVectorLength;
// Private members
FloatPoint3D directionVector;
FloatPoint3D privateColorVector;
float coneCutOffLimit;
float coneFullLight;
};
LightSource(LightType type)
: m_type(type)
{ }
virtual ~LightSource();
LightType type() const { return m_type; }
virtual TextStream& externalRepresentation(TextStream&) const = 0;
virtual PassRefPtr<LightSource> create(const FloatPoint3D& scale, const FloatSize& offset) const = 0;
virtual void initPaintingData(PaintingData&) const = 0;
// z is a float number, since it is the alpha value scaled by a user
// specified "surfaceScale" constant, which type is <number> in the SVG standard
virtual void updatePaintingData(PaintingData&, int x, int y, float z) const = 0;
virtual bool setAzimuth(float) { return false; }
virtual bool setElevation(float) { return false; }
virtual bool setX(float) { return false; }
virtual bool setY(float) { return false; }
virtual bool setZ(float) { return false; }
virtual bool setPointsAtX(float) { return false; }
virtual bool setPointsAtY(float) { return false; }
virtual bool setPointsAtZ(float) { return false; }
virtual bool setSpecularExponent(float) { return false; }
virtual bool setLimitingConeAngle(float) { return false; }
private:
LightType m_type;
};
} // namespace WebCore
#endif // LightSource_h