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 * aint 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 "GraphicsContext.h"
27 #include "PlatformString.h"
28 #include "Filter.h"
29
30 #include <wtf/StdLibExtras.h>
31
32 namespace WebCore {
33
create()34 PassRefPtr<SourceAlpha> SourceAlpha::create()
35 {
36 return adoptRef(new SourceAlpha);
37 }
38
effectName()39 const AtomicString& SourceAlpha::effectName()
40 {
41 DEFINE_STATIC_LOCAL(const AtomicString, s_effectName, ("SourceAlpha"));
42 return s_effectName;
43 }
44
calculateEffectRect(Filter * filter)45 FloatRect SourceAlpha::calculateEffectRect(Filter* filter)
46 {
47 FloatRect clippedSourceRect = filter->sourceImageRect();
48 if (filter->sourceImageRect().x() < filter->filterRegion().x())
49 clippedSourceRect.setX(filter->filterRegion().x());
50 if (filter->sourceImageRect().y() < filter->filterRegion().y())
51 clippedSourceRect.setY(filter->filterRegion().y());
52 setSubRegion(clippedSourceRect);
53 clippedSourceRect.scale(filter->filterResolution().width(), filter->filterResolution().height());
54 setScaledSubRegion(clippedSourceRect);
55 return filter->filterRegion();
56 }
57
apply(Filter * filter)58 void SourceAlpha::apply(Filter* filter)
59 {
60 GraphicsContext* filterContext = getEffectContext();
61 if (!filterContext)
62 return;
63
64 setIsAlphaImage(true);
65
66 FloatRect imageRect(FloatPoint(), filter->sourceImage()->image()->size());
67 filterContext->save();
68 filterContext->clipToImageBuffer(imageRect, filter->sourceImage());
69 filterContext->fillRect(imageRect, Color::black, DeviceColorSpace);
70 filterContext->restore();
71 }
72
dump()73 void SourceAlpha::dump()
74 {
75 }
76
77 } // namespace WebCore
78
79 #endif // ENABLE(FILTERS)
80