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 "PerspectiveTransformOperation.h" 28 29 #include <wtf/MathExtras.h> 30 31 using namespace std; 32 33 namespace WebCore { 34 35 PassRefPtr<TransformOperation> PerspectiveTransformOperation::blend(const TransformOperation* from, double progress, bool blendToIdentity) 36 { 37 if (from && !from->isSameType(*this)) 38 return this; 39 40 if (blendToIdentity) { 41 double p = m_p.calcFloatValue(1); 42 p = p + (1. - p) * progress; // FIXME: this seems wrong. https://bugs.webkit.org/show_bug.cgi?id=52700 43 return PerspectiveTransformOperation::create(Length(clampToPositiveInteger(p), Fixed)); 44 } 45 46 const PerspectiveTransformOperation* fromOp = static_cast<const PerspectiveTransformOperation*>(from); 47 Length fromP = fromOp ? fromOp->m_p : Length(m_p.type()); 48 Length toP = m_p; 49 50 TransformationMatrix fromT; 51 TransformationMatrix toT; 52 fromT.applyPerspective(fromP.calcFloatValue(1)); 53 toT.applyPerspective(toP.calcFloatValue(1)); 54 toT.blend(fromT, progress); 55 TransformationMatrix::DecomposedType decomp; 56 toT.decompose(decomp); 57 58 if (decomp.perspectiveZ) { 59 double val = -1.0 / decomp.perspectiveZ; 60 return PerspectiveTransformOperation::create(Length(clampToPositiveInteger(val), Fixed)); 61 } 62 return PerspectiveTransformOperation::create(Length(0, Fixed)); 63 } 64 65 } // namespace WebCore 66
