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27 #include "PerspectiveTransformOperation.h"
29 #include <wtf/MathExtras.h>
35 PassRefPtr<TransformOperation> PerspectiveTransformOperation::blend(const TransformOperation* from, double progress, bool blendToIdentity)
37 if (from && !from->isSameType(*this))
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));
46 const PerspectiveTransformOperation* fromOp = static_cast<const PerspectiveTransformOperation*>(from);
47 Length fromP = fromOp ? fromOp->m_p : Length(m_p.type());
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);
58 if (decomp.perspectiveZ) {
59 double val = -1.0 / decomp.perspectiveZ;
60 return PerspectiveTransformOperation::create(Length(clampToPositiveInteger(val), Fixed));
62 return PerspectiveTransformOperation::create(Length(0, Fixed));
65 } // namespace WebCore