| /* |
| * Copyright (C) 2009 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "PerspectiveTransformOperation.h" |
| |
| #include "AnimationUtilities.h" |
| #include <wtf/MathExtras.h> |
| #include <wtf/text/TextStream.h> |
| |
| namespace WebCore { |
| |
| bool PerspectiveTransformOperation::operator==(const TransformOperation& other) const |
| { |
| if (!isSameType(other)) |
| return false; |
| return m_p == downcast<PerspectiveTransformOperation>(other).m_p; |
| } |
| |
| Ref<TransformOperation> PerspectiveTransformOperation::blend(const TransformOperation* from, const BlendingContext& context, bool blendToIdentity) |
| { |
| if (!sharedPrimitiveType(from)) |
| return *this; |
| |
| // https://drafts.csswg.org/css-transforms-2/#interpolation-of-transform-functions |
| // says that we should run matrix decomposition and then run the rules for |
| // interpolation of matrices, but we know what those rules are going to |
| // yield, so just do that directly. |
| auto getInverse = [](const auto& operation) { |
| return !operation->isIdentity() ? (1.0 / (*operation->floatValue())) : 0.0; |
| }; |
| |
| double ourInverse = getInverse(this); |
| double fromPInverse, toPInverse; |
| if (blendToIdentity) { |
| fromPInverse = ourInverse; |
| toPInverse = 0.0; |
| } else { |
| fromPInverse = from ? getInverse(downcast<PerspectiveTransformOperation>(from)) : 0.0; |
| toPInverse = ourInverse; |
| } |
| |
| double pInverse = WebCore::blend(fromPInverse, toPInverse, context); |
| std::optional<Length> p; |
| if (pInverse > 0.0 && std::isnormal(pInverse)) { |
| p = Length(1.0 / pInverse, LengthType::Fixed); |
| } |
| return PerspectiveTransformOperation::create(p); |
| } |
| |
| void PerspectiveTransformOperation::dump(TextStream& ts) const |
| { |
| ts << type() << "("; |
| if (!m_p) |
| ts << "none"; |
| else |
| ts << m_p; |
| ts << ")"; |
| } |
| |
| } // namespace WebCore |