third_party/WebKit/Source/platform/transforms/PerspectiveTransformOperation.cpp

   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
  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(clampTo<int>(p, 0));
  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
  52     TransformationMatrix::DecomposedType decomp;
  53     if (!toT.decompose(decomp)) {
  54         // If we can't decompose, bail out of interpolation.
  55         const PerspectiveTransformOperation* usedOperation = progress > 0.5 ? this : fromOp;
  56         return PerspectiveTransformOperation::create(usedOperation->perspective());
  57     }
  58
  59     if (decomp.perspectiveZ) {
  60         double val = -1.0 / decomp.perspectiveZ;
  61         return PerspectiveTransformOperation::create(clampTo<int>(val, 0));
  62     }
  63     return PerspectiveTransformOperation::create(0);
  64 }
  65
  66 PassRefPtr<TransformOperation> PerspectiveTransformOperation::zoom(double factor)
  67 {
  68     return create(m_p * factor);
  69 }
  70
  71 } // namespace blink