1 /*
2 * Copyright (C) 2009 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "config.h"
27 #include "platform/transforms/PerspectiveTransformOperation.h"
28
29 #include "platform/animation/AnimationUtilities.h"
30 #include "wtf/MathExtras.h"
31
32 namespace blink {
33
blend(const TransformOperation * from,double progress,bool blendToIdentity)34 PassRefPtr<TransformOperation> PerspectiveTransformOperation::blend(const TransformOperation* from, double progress, bool blendToIdentity)
35 {
36 if (from && !from->isSameType(*this))
37 return this;
38
39 if (blendToIdentity) {
40 double p = blink::blend(m_p, 1., progress); // FIXME: this seems wrong. https://bugs.webkit.org/show_bug.cgi?id=52700
41 return PerspectiveTransformOperation::create(clampToPositiveInteger(p));
42 }
43
44 const PerspectiveTransformOperation* fromOp = static_cast<const PerspectiveTransformOperation*>(from);
45
46 TransformationMatrix fromT;
47 TransformationMatrix toT;
48 fromT.applyPerspective(fromOp ? fromOp->m_p : 0);
49 toT.applyPerspective(m_p);
50 toT.blend(fromT, progress);
51 TransformationMatrix::DecomposedType decomp;
52 toT.decompose(decomp);
53
54 if (decomp.perspectiveZ) {
55 double val = -1.0 / decomp.perspectiveZ;
56 return PerspectiveTransformOperation::create(clampToPositiveInteger(val));
57 }
58 return PerspectiveTransformOperation::create(0);
59 }
60
61 } // namespace blink
62