Home | History | Annotate | Download | only in graphics 
      1 /*
      2  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
      3  * Copyright (C) 2007 Alp Toker <alp (at) atoker.com>
      4  * Copyright (C) 2008 Torch Mobile, Inc.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  *
     15  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
     16  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
     19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     22  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
     23  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     25  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     26  */
     27 
     28 #ifndef Gradient_h
     29 #define Gradient_h
     30 
     31 #include "AffineTransform.h"
     32 #include "FloatPoint.h"
     33 #include "Generator.h"
     34 #include "GraphicsTypes.h"
     35 #include <wtf/PassRefPtr.h>
     36 #include <wtf/Vector.h>
     37 
     38 #if USE(CG)
     39 
     40 typedef struct CGContext* CGContextRef;
     41 
     42 #define USE_CG_SHADING defined(BUILDING_ON_TIGER) || defined(BUILDING_ON_LEOPARD)
     43 
     44 #if USE_CG_SHADING
     45 typedef struct CGShading* CGShadingRef;
     46 typedef CGShadingRef PlatformGradient;
     47 #else
     48 typedef struct CGGradient* CGGradientRef;
     49 typedef CGGradientRef PlatformGradient;
     50 #endif
     51 
     52 #elif PLATFORM(QT)
     53 QT_BEGIN_NAMESPACE
     54 class QGradient;
     55 QT_END_NAMESPACE
     56 typedef QGradient* PlatformGradient;
     57 #elif USE(CAIRO)
     58 typedef struct _cairo_pattern cairo_pattern_t;
     59 typedef cairo_pattern_t* PlatformGradient;
     60 #elif USE(SKIA)
     61 #if PLATFORM(ANDROID)
     62 #include "SkShader.h"
     63 typedef class PlatformGradientRec* PlatformGradient;
     64 #else
     65 class SkShader;
     66 typedef class SkShader* PlatformGradient;
     67 typedef class SkShader* PlatformPattern;
     68 #endif
     69 #elif PLATFORM(HAIKU)
     70 class BGradient;
     71 typedef BGradient* PlatformGradient;
     72 #else
     73 typedef void* PlatformGradient;
     74 #endif
     75 
     76 namespace WebCore {
     77 
     78     class Color;
     79 
     80     class Gradient : public Generator {
     81     public:
     82         static PassRefPtr<Gradient> create(const FloatPoint& p0, const FloatPoint& p1)
     83         {
     84             return adoptRef(new Gradient(p0, p1));
     85         }
     86         static PassRefPtr<Gradient> create(const FloatPoint& p0, float r0, const FloatPoint& p1, float r1, float aspectRatio = 1)
     87         {
     88             return adoptRef(new Gradient(p0, r0, p1, r1, aspectRatio));
     89         }
     90         virtual ~Gradient();
     91 
     92         struct ColorStop;
     93         void addColorStop(const ColorStop&);
     94         void addColorStop(float, const Color&);
     95 
     96         void getColor(float value, float* r, float* g, float* b, float* a) const;
     97         bool hasAlpha() const;
     98 
     99         bool isRadial() const { return m_radial; }
    100         bool isZeroSize() const { return m_p0.x() == m_p1.x() && m_p0.y() == m_p1.y() && (!m_radial || m_r0 == m_r1); }
    101 
    102         const FloatPoint& p0() const { return m_p0; }
    103         const FloatPoint& p1() const { return m_p1; }
    104 
    105         void setP0(const FloatPoint& p) { m_p0 = p; }
    106         void setP1(const FloatPoint& p) { m_p1 = p; }
    107 
    108         float startRadius() const { return m_r0; }
    109         float endRadius() const { return m_r1; }
    110 
    111         void setStartRadius(float r) { m_r0 = r; }
    112         void setEndRadius(float r) { m_r1 = r; }
    113 
    114         float aspectRatio() const { return m_aspectRatio; }
    115 
    116 #if OS(WINCE) && !PLATFORM(QT)
    117         const Vector<ColorStop, 2>& getStops() const;
    118 #else
    119 #if PLATFORM(ANDROID)
    120         SkShader* getShader(SkShader::TileMode);
    121 #endif
    122         PlatformGradient platformGradient();
    123 #endif
    124 
    125         struct ColorStop {
    126             float stop;
    127             float red;
    128             float green;
    129             float blue;
    130             float alpha;
    131 
    132             ColorStop() : stop(0), red(0), green(0), blue(0), alpha(0) { }
    133             ColorStop(float s, float r, float g, float b, float a) : stop(s), red(r), green(g), blue(b), alpha(a) { }
    134         };
    135 
    136         void setStopsSorted(bool s) { m_stopsSorted = s; }
    137 
    138         void setSpreadMethod(GradientSpreadMethod);
    139         GradientSpreadMethod spreadMethod() { return m_spreadMethod; }
    140         void setGradientSpaceTransform(const AffineTransform& gradientSpaceTransformation);
    141         // Qt and CG transform the gradient at draw time
    142         AffineTransform gradientSpaceTransform() { return m_gradientSpaceTransformation; }
    143 
    144         virtual void fill(GraphicsContext*, const FloatRect&);
    145         virtual void adjustParametersForTiledDrawing(IntSize& size, FloatRect& srcRect);
    146 
    147         void setPlatformGradientSpaceTransform(const AffineTransform& gradientSpaceTransformation);
    148 
    149 #if USE(CG)
    150         void paint(CGContextRef);
    151         void paint(GraphicsContext*);
    152 #endif
    153 
    154     private:
    155         Gradient(const FloatPoint& p0, const FloatPoint& p1);
    156         Gradient(const FloatPoint& p0, float r0, const FloatPoint& p1, float r1, float aspectRatio);
    157 
    158         void platformInit() { m_gradient = 0; }
    159         void platformDestroy();
    160 
    161         int findStop(float value) const;
    162         void sortStopsIfNecessary();
    163 
    164         bool m_radial;
    165         FloatPoint m_p0;
    166         FloatPoint m_p1;
    167         float m_r0;
    168         float m_r1;
    169         float m_aspectRatio; // For elliptical gradient, width / height.
    170         mutable Vector<ColorStop, 2> m_stops;
    171         mutable bool m_stopsSorted;
    172         mutable int m_lastStop;
    173         GradientSpreadMethod m_spreadMethod;
    174         AffineTransform m_gradientSpaceTransformation;
    175 
    176         PlatformGradient m_gradient;
    177     };
    178 
    179 } //namespace
    180 
    181 #endif
    182