1 /*
2 * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 #include "config.h"
21
22 #if ENABLE(FILTERS)
23 #include "SourceAlpha.h"
24
25 #include "Color.h"
26 #include "Filter.h"
27 #include "GraphicsContext.h"
28 #include "PlatformString.h"
29 #include "RenderTreeAsText.h"
30 #include "TextStream.h"
31
32 #include <wtf/StdLibExtras.h>
33
34 namespace WebCore {
35
create(Filter * filter)36 PassRefPtr<SourceAlpha> SourceAlpha::create(Filter* filter)
37 {
38 return adoptRef(new SourceAlpha(filter));
39 }
40
effectName()41 const AtomicString& SourceAlpha::effectName()
42 {
43 DEFINE_STATIC_LOCAL(const AtomicString, s_effectName, ("SourceAlpha"));
44 return s_effectName;
45 }
46
determineAbsolutePaintRect()47 void SourceAlpha::determineAbsolutePaintRect()
48 {
49 Filter* filter = this->filter();
50 FloatRect paintRect = filter->sourceImageRect();
51 paintRect.scale(filter->filterResolution().width(), filter->filterResolution().height());
52 setAbsolutePaintRect(enclosingIntRect(paintRect));
53 }
54
apply()55 void SourceAlpha::apply()
56 {
57 if (hasResult())
58 return;
59 ImageBuffer* resultImage = createImageBufferResult();
60 Filter* filter = this->filter();
61 if (!resultImage || !filter->sourceImage())
62 return;
63
64 setIsAlphaImage(true);
65
66 FloatRect imageRect(FloatPoint(), absolutePaintRect().size());
67 GraphicsContext* filterContext = resultImage->context();
68 GraphicsContextStateSaver stateSaver(*filterContext);
69 filterContext->clipToImageBuffer(filter->sourceImage(), imageRect);
70 filterContext->fillRect(imageRect, Color::black, ColorSpaceDeviceRGB);
71 }
72
dump()73 void SourceAlpha::dump()
74 {
75 }
76
externalRepresentation(TextStream & ts,int indent) const77 TextStream& SourceAlpha::externalRepresentation(TextStream& ts, int indent) const
78 {
79 writeIndent(ts, indent);
80 ts << "[SourceAlpha]\n";
81 return ts;
82 }
83
84 } // namespace WebCore
85
86 #endif // ENABLE(FILTERS)
87