1 /*
2 * Copyright (C) 2006, 2007, 2008 Apple Computer, Inc. All rights reserved.
3 * Copyright (C) 2007 Alp Toker <alp@atoker.com>
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include "config.h"
28 #include "Gradient.h"
29
30 #include "GraphicsContextCG.h"
31 #include <ApplicationServices/ApplicationServices.h>
32 #include <wtf/RetainPtr.h>
33
34 namespace WebCore {
35
platformDestroy()36 void Gradient::platformDestroy()
37 {
38 #if USE_CG_SHADING
39 CGShadingRelease(m_gradient);
40 #else
41 CGGradientRelease(m_gradient);
42 #endif
43 m_gradient = 0;
44 }
45
46 #if USE_CG_SHADING
gradientCallback(void * info,const CGFloat * in,CGFloat * out)47 static void gradientCallback(void* info, const CGFloat* in, CGFloat* out)
48 {
49 float r, g, b, a;
50 static_cast<const Gradient*>(info)->getColor(*in, &r, &g, &b, &a);
51 out[0] = r;
52 out[1] = g;
53 out[2] = b;
54 out[3] = a;
55 }
56
platformGradient()57 CGShadingRef Gradient::platformGradient()
58 {
59 if (m_gradient)
60 return m_gradient;
61
62 const CGFloat intervalRanges[2] = { 0, 1 };
63 const CGFloat colorComponentRanges[4 * 2] = { 0, 1, 0, 1, 0, 1, 0, 1 };
64 const CGFunctionCallbacks gradientCallbacks = { 0, gradientCallback, 0 };
65 RetainPtr<CGFunctionRef> colorFunction(AdoptCF, CGFunctionCreate(this, 1, intervalRanges, 4, colorComponentRanges, &gradientCallbacks));
66
67 CGColorSpaceRef colorSpace = deviceRGBColorSpaceRef();
68
69 if (m_radial)
70 m_gradient = CGShadingCreateRadial(colorSpace, m_p0, m_r0, m_p1, m_r1, colorFunction.get(), true, true);
71 else
72 m_gradient = CGShadingCreateAxial(colorSpace, m_p0, m_p1, colorFunction.get(), true, true);
73
74 return m_gradient;
75 }
76 #else
platformGradient()77 CGGradientRef Gradient::platformGradient()
78 {
79 if (m_gradient)
80 return m_gradient;
81
82 sortStopsIfNecessary();
83
84 const int cReservedStops = 3;
85 Vector<CGFloat, 4 * cReservedStops> colorComponents;
86 colorComponents.reserveCapacity(m_stops.size() * 4); // RGBA components per stop
87
88 Vector<CGFloat, cReservedStops> locations;
89 locations.reserveCapacity(m_stops.size());
90
91 for (size_t i = 0; i < m_stops.size(); ++i) {
92 colorComponents.uncheckedAppend(m_stops[i].red);
93 colorComponents.uncheckedAppend(m_stops[i].green);
94 colorComponents.uncheckedAppend(m_stops[i].blue);
95 colorComponents.uncheckedAppend(m_stops[i].alpha);
96
97 locations.uncheckedAppend(m_stops[i].stop);
98 }
99
100 m_gradient = CGGradientCreateWithColorComponents(deviceRGBColorSpaceRef(), colorComponents.data(), locations.data(), m_stops.size());
101
102 return m_gradient;
103 }
104 #endif
105
fill(GraphicsContext * context,const FloatRect & rect)106 void Gradient::fill(GraphicsContext* context, const FloatRect& rect)
107 {
108 context->clip(rect);
109 paint(context);
110 }
111
paint(GraphicsContext * context)112 void Gradient::paint(GraphicsContext* context)
113 {
114 CGContextRef ctx = context->platformContext();
115 paint(ctx);
116 }
117
paint(CGContextRef context)118 void Gradient::paint(CGContextRef context)
119 {
120 #if USE_CG_SHADING
121 CGContextDrawShading(context, platformGradient());
122 #else
123 CGGradientDrawingOptions extendOptions = kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation;
124 if (m_radial) {
125 bool needScaling = aspectRatio() != 1;
126 if (needScaling) {
127 CGContextSaveGState(context);
128 // Scale from the center of the gradient. We only ever scale non-deprecated gradients,
129 // for which m_p0 == m_p1.
130 ASSERT(m_p0 == m_p1);
131 CGContextTranslateCTM(context, m_p0.x(), m_p0.y());
132 CGContextScaleCTM(context, 1, 1 / aspectRatio());
133 CGContextTranslateCTM(context, -m_p0.x(), -m_p0.y());
134 }
135
136 CGContextDrawRadialGradient(context, platformGradient(), m_p0, m_r0, m_p1, m_r1, extendOptions);
137
138 if (needScaling)
139 CGContextRestoreGState(context);
140 } else
141 CGContextDrawLinearGradient(context, platformGradient(), m_p0, m_p1, extendOptions);
142 #endif
143 }
144
145 } //namespace
146