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46a0e62893
Use Servo backend to decompose/interpolate/recompose matrices on both
main thread and compositor thread.
Note: Due there may be differences in precision used to represent the
components, and the computation of matrix interpolation are not
exactly same (still following the formulas in spec). There are some
tiny differences between the interpolation results of 2d/3d
matrices on Gecko and Servo, especially if there is skew() or any 3d
transform function.
MozReview-Commit-ID: 6T8vlR4MJGr
--HG--
extra : rebase_source : 3309f4a4541c6612109a441c38bb896deb83c018
1350 lines
46 KiB
C++
1350 lines
46 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/*
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* A class used for intermediate representations of the -moz-transform property.
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*/
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#include "nsStyleTransformMatrix.h"
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#include "nsCSSValue.h"
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#include "nsLayoutUtils.h"
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#include "nsPresContext.h"
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#include "nsRuleNode.h"
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#include "nsSVGUtils.h"
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#include "nsCSSKeywords.h"
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#include "mozilla/ServoBindings.h"
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#include "mozilla/StyleAnimationValue.h"
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#include "gfxMatrix.h"
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#include "gfxQuaternion.h"
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using namespace mozilla;
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using namespace mozilla::gfx;
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namespace nsStyleTransformMatrix {
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/* Note on floating point precision: The transform matrix is an array
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* of single precision 'float's, and so are most of the input values
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* we get from the style system, but intermediate calculations
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* involving angles need to be done in 'double'.
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*/
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// Define UNIFIED_CONTINUATIONS here and in nsDisplayList.cpp
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// to have the transform property try
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// to transform content with continuations as one unified block instead of
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// several smaller ones. This is currently disabled because it doesn't work
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// correctly, since when the frames are initially being reflowed, their
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// continuations all compute their bounding rects independently of each other
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// and consequently get the wrong value.
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//#define UNIFIED_CONTINUATIONS
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void
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TransformReferenceBox::EnsureDimensionsAreCached()
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{
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if (mIsCached) {
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return;
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}
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MOZ_ASSERT(mFrame);
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mIsCached = true;
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if (mFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT) {
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if (!nsLayoutUtils::SVGTransformBoxEnabled()) {
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mX = -mFrame->GetPosition().x;
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mY = -mFrame->GetPosition().y;
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Size contextSize = nsSVGUtils::GetContextSize(mFrame);
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mWidth = nsPresContext::CSSPixelsToAppUnits(contextSize.width);
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mHeight = nsPresContext::CSSPixelsToAppUnits(contextSize.height);
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} else
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if (mFrame->StyleDisplay()->mTransformBox == StyleGeometryBox::FillBox) {
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// Percentages in transforms resolve against the SVG bbox, and the
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// transform is relative to the top-left of the SVG bbox.
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nsRect bboxInAppUnits =
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nsLayoutUtils::ComputeGeometryBox(const_cast<nsIFrame*>(mFrame),
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StyleGeometryBox::FillBox);
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// The mRect of an SVG nsIFrame is its user space bounds *including*
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// stroke and markers, whereas bboxInAppUnits is its user space bounds
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// including fill only. We need to note the offset of the reference box
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// from the frame's mRect in mX/mY.
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mX = bboxInAppUnits.x - mFrame->GetPosition().x;
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mY = bboxInAppUnits.y - mFrame->GetPosition().y;
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mWidth = bboxInAppUnits.width;
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mHeight = bboxInAppUnits.height;
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} else {
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// The value 'border-box' is treated as 'view-box' for SVG content.
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MOZ_ASSERT(mFrame->StyleDisplay()->mTransformBox ==
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StyleGeometryBox::ViewBox ||
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mFrame->StyleDisplay()->mTransformBox ==
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StyleGeometryBox::BorderBox,
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"Unexpected value for 'transform-box'");
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// Percentages in transforms resolve against the width/height of the
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// nearest viewport (or its viewBox if one is applied), and the
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// transform is relative to {0,0} in current user space.
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mX = -mFrame->GetPosition().x;
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mY = -mFrame->GetPosition().y;
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Size contextSize = nsSVGUtils::GetContextSize(mFrame);
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mWidth = nsPresContext::CSSPixelsToAppUnits(contextSize.width);
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mHeight = nsPresContext::CSSPixelsToAppUnits(contextSize.height);
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}
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return;
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}
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// If UNIFIED_CONTINUATIONS is not defined, this is simply the frame's
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// bounding rectangle, translated to the origin. Otherwise, it is the
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// smallest rectangle containing a frame and all of its continuations. For
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// example, if there is a <span> element with several continuations split
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// over several lines, this function will return the rectangle containing all
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// of those continuations.
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nsRect rect;
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#ifndef UNIFIED_CONTINUATIONS
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rect = mFrame->GetRect();
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#else
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// Iterate the continuation list, unioning together the bounding rects:
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for (const nsIFrame *currFrame = mFrame->FirstContinuation();
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currFrame != nullptr;
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currFrame = currFrame->GetNextContinuation())
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{
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// Get the frame rect in local coordinates, then translate back to the
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// original coordinates:
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rect.UnionRect(result, nsRect(currFrame->GetOffsetTo(mFrame),
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currFrame->GetSize()));
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}
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#endif
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mX = 0;
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mY = 0;
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mWidth = rect.Width();
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mHeight = rect.Height();
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}
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void
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TransformReferenceBox::Init(const nsSize& aDimensions)
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{
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MOZ_ASSERT(!mFrame && !mIsCached);
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mX = 0;
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mY = 0;
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mWidth = aDimensions.width;
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mHeight = aDimensions.height;
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mIsCached = true;
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}
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float
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ProcessTranslatePart(const nsCSSValue& aValue,
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nsStyleContext* aContext,
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nsPresContext* aPresContext,
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RuleNodeCacheConditions& aConditions,
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TransformReferenceBox* aRefBox,
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TransformReferenceBox::DimensionGetter aDimensionGetter)
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{
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nscoord offset = 0;
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float percent = 0.0f;
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if (aValue.GetUnit() == eCSSUnit_Percent) {
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percent = aValue.GetPercentValue();
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} else if (aValue.GetUnit() == eCSSUnit_Pixel ||
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aValue.GetUnit() == eCSSUnit_Number) {
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// Handle this here (even though nsRuleNode::CalcLength handles it
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// fine) so that callers are allowed to pass a null style context
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// and pres context to SetToTransformFunction if they know (as
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// StyleAnimationValue does) that all lengths within the transform
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// function have already been computed to pixels and percents.
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//
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// Raw numbers are treated as being pixels.
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//
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// Don't convert to aValue to AppUnits here to avoid precision issues.
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return aValue.GetFloatValue();
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} else if (aValue.IsCalcUnit()) {
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nsRuleNode::ComputedCalc result =
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nsRuleNode::SpecifiedCalcToComputedCalc(aValue, aContext, aPresContext,
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aConditions);
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percent = result.mPercent;
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offset = result.mLength;
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} else {
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offset = nsRuleNode::CalcLength(aValue, aContext, aPresContext,
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aConditions);
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}
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float translation = NSAppUnitsToFloatPixels(offset,
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nsPresContext::AppUnitsPerCSSPixel());
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// We want to avoid calling aDimensionGetter if there's no percentage to be
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// resolved (for performance reasons - see TransformReferenceBox).
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if (percent != 0.0f && aRefBox && !aRefBox->IsEmpty()) {
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translation += percent *
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NSAppUnitsToFloatPixels((aRefBox->*aDimensionGetter)(),
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nsPresContext::AppUnitsPerCSSPixel());
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}
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return translation;
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}
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/**
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* Helper functions to process all the transformation function types.
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*
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* These take a matrix parameter to accumulate the current matrix.
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*/
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/* Helper function to process a matrix entry. */
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static void
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ProcessMatrix(Matrix4x4& aMatrix,
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const nsCSSValue::Array* aData,
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nsStyleContext* aContext,
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nsPresContext* aPresContext,
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RuleNodeCacheConditions& aConditions,
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TransformReferenceBox& aRefBox)
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{
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NS_PRECONDITION(aData->Count() == 7, "Invalid array!");
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gfxMatrix result;
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/* Take the first four elements out of the array as floats and store
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* them.
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*/
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result._11 = aData->Item(1).GetFloatValue();
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result._12 = aData->Item(2).GetFloatValue();
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result._21 = aData->Item(3).GetFloatValue();
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result._22 = aData->Item(4).GetFloatValue();
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/* The last two elements have their length parts stored in aDelta
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* and their percent parts stored in aX[0] and aY[1].
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*/
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result._31 = ProcessTranslatePart(aData->Item(5),
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aContext, aPresContext, aConditions,
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&aRefBox, &TransformReferenceBox::Width);
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result._32 = ProcessTranslatePart(aData->Item(6),
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aContext, aPresContext, aConditions,
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&aRefBox, &TransformReferenceBox::Height);
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aMatrix = result * aMatrix;
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}
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static void
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ProcessMatrix3D(Matrix4x4& aMatrix,
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const nsCSSValue::Array* aData,
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nsStyleContext* aContext,
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nsPresContext* aPresContext,
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RuleNodeCacheConditions& aConditions,
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TransformReferenceBox& aRefBox)
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{
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NS_PRECONDITION(aData->Count() == 17, "Invalid array!");
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Matrix4x4 temp;
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temp._11 = aData->Item(1).GetFloatValue();
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temp._12 = aData->Item(2).GetFloatValue();
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temp._13 = aData->Item(3).GetFloatValue();
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temp._14 = aData->Item(4).GetFloatValue();
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temp._21 = aData->Item(5).GetFloatValue();
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temp._22 = aData->Item(6).GetFloatValue();
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temp._23 = aData->Item(7).GetFloatValue();
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temp._24 = aData->Item(8).GetFloatValue();
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temp._31 = aData->Item(9).GetFloatValue();
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temp._32 = aData->Item(10).GetFloatValue();
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temp._33 = aData->Item(11).GetFloatValue();
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temp._34 = aData->Item(12).GetFloatValue();
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temp._44 = aData->Item(16).GetFloatValue();
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temp._41 = ProcessTranslatePart(aData->Item(13),
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aContext, aPresContext, aConditions,
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&aRefBox, &TransformReferenceBox::Width);
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temp._42 = ProcessTranslatePart(aData->Item(14),
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aContext, aPresContext, aConditions,
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&aRefBox, &TransformReferenceBox::Height);
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temp._43 = ProcessTranslatePart(aData->Item(15),
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aContext, aPresContext, aConditions,
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nullptr);
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aMatrix = temp * aMatrix;
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}
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// For accumulation for transform functions, |aOne| corresponds to |aB| and
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// |aTwo| corresponds to |aA| for StyleAnimationValue::Accumulate().
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class Accumulate {
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public:
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template<typename T>
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static T operate(const T& aOne, const T& aTwo, double aCoeff)
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{
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return aOne + aTwo * aCoeff;
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}
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static Point4D operateForPerspective(const Point4D& aOne,
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const Point4D& aTwo,
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double aCoeff)
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{
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return (aOne - Point4D(0, 0, 0, 1)) +
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(aTwo - Point4D(0, 0, 0, 1)) * aCoeff +
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Point4D(0, 0, 0, 1);
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}
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static Point3D operateForScale(const Point3D& aOne,
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const Point3D& aTwo,
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double aCoeff)
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{
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// For scale, the identify element is 1, see AddTransformScale in
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// StyleAnimationValue.cpp.
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return (aOne - Point3D(1, 1, 1)) +
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(aTwo - Point3D(1, 1, 1)) * aCoeff +
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Point3D(1, 1, 1);
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}
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static Matrix4x4 operateForRotate(const gfxQuaternion& aOne,
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const gfxQuaternion& aTwo,
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double aCoeff)
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{
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if (aCoeff == 0.0) {
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return aOne.ToMatrix();
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}
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double theta = acos(mozilla::clamped(aTwo.w, -1.0, 1.0));
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double scale = (theta != 0.0) ? 1.0 / sin(theta) : 0.0;
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theta *= aCoeff;
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scale *= sin(theta);
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gfxQuaternion result = gfxQuaternion(scale * aTwo.x,
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scale * aTwo.y,
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scale * aTwo.z,
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cos(theta)) * aOne;
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return result.ToMatrix();
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}
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static Matrix4x4 operateByServo(const Matrix4x4& aMatrix1,
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const Matrix4x4& aMatrix2,
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double aCount)
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{
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Matrix4x4 result;
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Servo_MatrixTransform_Operate(MatrixTransformOperator::Accumulate,
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&aMatrix1.components,
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&aMatrix2.components,
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aCount,
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&result.components);
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return result;
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}
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};
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class Interpolate {
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public:
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template<typename T>
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static T operate(const T& aOne, const T& aTwo, double aCoeff)
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{
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return aOne + (aTwo - aOne) * aCoeff;
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}
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static Point4D operateForPerspective(const Point4D& aOne,
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const Point4D& aTwo,
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double aCoeff)
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{
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return aOne + (aTwo - aOne) * aCoeff;
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}
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static Point3D operateForScale(const Point3D& aOne,
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const Point3D& aTwo,
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double aCoeff)
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{
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return aOne + (aTwo - aOne) * aCoeff;
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}
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static Matrix4x4 operateForRotate(const gfxQuaternion& aOne,
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const gfxQuaternion& aTwo,
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double aCoeff)
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{
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return aOne.Slerp(aTwo, aCoeff).ToMatrix();
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}
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static Matrix4x4 operateByServo(const Matrix4x4& aMatrix1,
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const Matrix4x4& aMatrix2,
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double aProgress)
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{
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Matrix4x4 result;
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Servo_MatrixTransform_Operate(MatrixTransformOperator::Interpolate,
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&aMatrix1.components,
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&aMatrix2.components,
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aProgress,
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&result.components);
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return result;
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}
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};
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/**
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* Calculate 2 matrices by decomposing them with Operator.
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*
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* @param aMatrix1 First matrix, using CSS pixel units.
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* @param aMatrix2 Second matrix, using CSS pixel units.
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* @param aProgress Coefficient for the Operator.
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*/
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template <typename Operator>
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static Matrix4x4
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OperateTransformMatrix(const Matrix4x4 &aMatrix1,
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const Matrix4x4 &aMatrix2,
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double aProgress)
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{
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// Decompose both matrices
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// TODO: What do we do if one of these returns false (singular matrix)
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Point3D scale1(1, 1, 1), translate1;
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Point4D perspective1(0, 0, 0, 1);
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gfxQuaternion rotate1;
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nsStyleTransformMatrix::ShearArray shear1{0.0f, 0.0f, 0.0f};
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Point3D scale2(1, 1, 1), translate2;
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Point4D perspective2(0, 0, 0, 1);
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gfxQuaternion rotate2;
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nsStyleTransformMatrix::ShearArray shear2{0.0f, 0.0f, 0.0f};
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Matrix matrix2d1, matrix2d2;
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if (aMatrix1.Is2D(&matrix2d1) && aMatrix2.Is2D(&matrix2d2)) {
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Decompose2DMatrix(matrix2d1, scale1, shear1, rotate1, translate1);
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Decompose2DMatrix(matrix2d2, scale2, shear2, rotate2, translate2);
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} else {
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Decompose3DMatrix(aMatrix1, scale1, shear1,
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rotate1, translate1, perspective1);
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Decompose3DMatrix(aMatrix2, scale2, shear2,
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rotate2, translate2, perspective2);
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}
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Matrix4x4 result;
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// Operate each of the pieces in response to |Operator|.
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Point4D perspective =
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Operator::operateForPerspective(perspective1, perspective2, aProgress);
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result.SetTransposedVector(3, perspective);
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Point3D translate =
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Operator::operate(translate1, translate2, aProgress);
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result.PreTranslate(translate.x, translate.y, translate.z);
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Matrix4x4 rotate = Operator::operateForRotate(rotate1, rotate2, aProgress);
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if (!rotate.IsIdentity()) {
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result = rotate * result;
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}
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// TODO: Would it be better to operate these as angles?
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// How do we convert back to angles?
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float yzshear =
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Operator::operate(shear1[ShearType::YZSHEAR],
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shear2[ShearType::YZSHEAR],
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aProgress);
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if (yzshear != 0.0) {
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result.SkewYZ(yzshear);
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}
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float xzshear =
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Operator::operate(shear1[ShearType::XZSHEAR],
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shear2[ShearType::XZSHEAR],
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aProgress);
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if (xzshear != 0.0) {
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result.SkewXZ(xzshear);
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}
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float xyshear =
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Operator::operate(shear1[ShearType::XYSHEAR],
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shear2[ShearType::XYSHEAR],
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aProgress);
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if (xyshear != 0.0) {
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result.SkewXY(xyshear);
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}
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Point3D scale =
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Operator::operateForScale(scale1, scale2, aProgress);
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if (scale != Point3D(1.0, 1.0, 1.0)) {
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result.PreScale(scale.x, scale.y, scale.z);
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}
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return result;
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}
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template <typename Operator>
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static Matrix4x4
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OperateTransformMatrixByServo(const Matrix4x4 &aMatrix1,
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const Matrix4x4 &aMatrix2,
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double aProgress)
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{
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return Operator::operateByServo(aMatrix1, aMatrix2, aProgress);
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}
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template <typename Operator>
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static void
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ProcessMatrixOperator(Matrix4x4& aMatrix,
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const nsCSSValue::Array* aData,
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nsStyleContext* aContext,
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nsPresContext* aPresContext,
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RuleNodeCacheConditions& aConditions,
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TransformReferenceBox& aRefBox,
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bool* aContains3dTransform)
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{
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NS_PRECONDITION(aData->Count() == 4, "Invalid array!");
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auto readTransform = [&](const nsCSSValue& aValue) -> Matrix4x4 {
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const nsCSSValueList* list = nullptr;
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|
switch (aValue.GetUnit()) {
|
|
case eCSSUnit_List:
|
|
// For Gecko style backend.
|
|
list = aValue.GetListValue();
|
|
break;
|
|
case eCSSUnit_SharedList:
|
|
// For Servo style backend. The transform lists of interpolatematrix
|
|
// are not created on the main thread (i.e. during parallel traversal),
|
|
// and nsCSSValueList_heap is not thread safe. Therefore, we use
|
|
// nsCSSValueSharedList as a workaround.
|
|
list = aValue.GetSharedListValue()->mHead;
|
|
break;
|
|
default:
|
|
list = nullptr;
|
|
}
|
|
|
|
Matrix4x4 matrix;
|
|
if (!list) {
|
|
return matrix;
|
|
}
|
|
|
|
float appUnitPerCSSPixel = nsPresContext::AppUnitsPerCSSPixel();
|
|
matrix = nsStyleTransformMatrix::ReadTransforms(list,
|
|
aContext,
|
|
aPresContext,
|
|
aConditions,
|
|
aRefBox,
|
|
appUnitPerCSSPixel,
|
|
aContains3dTransform);
|
|
return matrix;
|
|
};
|
|
|
|
Matrix4x4 matrix1 = readTransform(aData->Item(1));
|
|
Matrix4x4 matrix2 = readTransform(aData->Item(2));
|
|
double progress = aData->Item(3).GetPercentValue();
|
|
|
|
if (aContext && aContext->StyleSource().IsServoComputedValues()) {
|
|
aMatrix =
|
|
OperateTransformMatrixByServo<Operator>(matrix1, matrix2, progress)
|
|
* aMatrix;
|
|
return;
|
|
}
|
|
|
|
aMatrix =
|
|
OperateTransformMatrix<Operator>(matrix1, matrix2, progress) * aMatrix;
|
|
}
|
|
|
|
/* Helper function to process two matrices that we need to interpolate between */
|
|
void
|
|
ProcessInterpolateMatrix(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox,
|
|
bool* aContains3dTransform)
|
|
{
|
|
ProcessMatrixOperator<Interpolate>(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox,
|
|
aContains3dTransform);
|
|
}
|
|
|
|
void
|
|
ProcessAccumulateMatrix(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox,
|
|
bool* aContains3dTransform)
|
|
{
|
|
ProcessMatrixOperator<Accumulate>(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox,
|
|
aContains3dTransform);
|
|
}
|
|
|
|
/* Helper function to process a translatex function. */
|
|
static void
|
|
ProcessTranslateX(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Invalid array!");
|
|
|
|
Point3D temp;
|
|
|
|
temp.x = ProcessTranslatePart(aData->Item(1),
|
|
aContext, aPresContext, aConditions,
|
|
&aRefBox, &TransformReferenceBox::Width);
|
|
aMatrix.PreTranslate(temp);
|
|
}
|
|
|
|
/* Helper function to process a translatey function. */
|
|
static void
|
|
ProcessTranslateY(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Invalid array!");
|
|
|
|
Point3D temp;
|
|
|
|
temp.y = ProcessTranslatePart(aData->Item(1),
|
|
aContext, aPresContext, aConditions,
|
|
&aRefBox, &TransformReferenceBox::Height);
|
|
aMatrix.PreTranslate(temp);
|
|
}
|
|
|
|
static void
|
|
ProcessTranslateZ(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Invalid array!");
|
|
|
|
Point3D temp;
|
|
|
|
temp.z = ProcessTranslatePart(aData->Item(1), aContext,
|
|
aPresContext, aConditions,
|
|
nullptr);
|
|
aMatrix.PreTranslate(temp);
|
|
}
|
|
|
|
/* Helper function to process a translate function. */
|
|
static void
|
|
ProcessTranslate(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2 || aData->Count() == 3, "Invalid array!");
|
|
|
|
Point3D temp;
|
|
|
|
temp.x = ProcessTranslatePart(aData->Item(1),
|
|
aContext, aPresContext, aConditions,
|
|
&aRefBox, &TransformReferenceBox::Width);
|
|
|
|
/* If we read in a Y component, set it appropriately */
|
|
if (aData->Count() == 3) {
|
|
temp.y = ProcessTranslatePart(aData->Item(2),
|
|
aContext, aPresContext, aConditions,
|
|
&aRefBox, &TransformReferenceBox::Height);
|
|
}
|
|
aMatrix.PreTranslate(temp);
|
|
}
|
|
|
|
static void
|
|
ProcessTranslate3D(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 4, "Invalid array!");
|
|
|
|
Point3D temp;
|
|
|
|
temp.x = ProcessTranslatePart(aData->Item(1),
|
|
aContext, aPresContext, aConditions,
|
|
&aRefBox, &TransformReferenceBox::Width);
|
|
|
|
temp.y = ProcessTranslatePart(aData->Item(2),
|
|
aContext, aPresContext, aConditions,
|
|
&aRefBox, &TransformReferenceBox::Height);
|
|
|
|
temp.z = ProcessTranslatePart(aData->Item(3),
|
|
aContext, aPresContext, aConditions,
|
|
nullptr);
|
|
|
|
aMatrix.PreTranslate(temp);
|
|
}
|
|
|
|
/* Helper function to set up a scale matrix. */
|
|
static void
|
|
ProcessScaleHelper(Matrix4x4& aMatrix,
|
|
float aXScale,
|
|
float aYScale,
|
|
float aZScale)
|
|
{
|
|
aMatrix.PreScale(aXScale, aYScale, aZScale);
|
|
}
|
|
|
|
/* Process a scalex function. */
|
|
static void
|
|
ProcessScaleX(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Bad array!");
|
|
ProcessScaleHelper(aMatrix, aData->Item(1).GetFloatValue(), 1.0f, 1.0f);
|
|
}
|
|
|
|
/* Process a scaley function. */
|
|
static void
|
|
ProcessScaleY(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Bad array!");
|
|
ProcessScaleHelper(aMatrix, 1.0f, aData->Item(1).GetFloatValue(), 1.0f);
|
|
}
|
|
|
|
static void
|
|
ProcessScaleZ(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Bad array!");
|
|
ProcessScaleHelper(aMatrix, 1.0f, 1.0f, aData->Item(1).GetFloatValue());
|
|
}
|
|
|
|
static void
|
|
ProcessScale3D(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 4, "Bad array!");
|
|
ProcessScaleHelper(aMatrix,
|
|
aData->Item(1).GetFloatValue(),
|
|
aData->Item(2).GetFloatValue(),
|
|
aData->Item(3).GetFloatValue());
|
|
}
|
|
|
|
/* Process a scale function. */
|
|
static void
|
|
ProcessScale(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2 || aData->Count() == 3, "Bad array!");
|
|
/* We either have one element or two. If we have one, it's for both X and Y.
|
|
* Otherwise it's one for each.
|
|
*/
|
|
const nsCSSValue& scaleX = aData->Item(1);
|
|
const nsCSSValue& scaleY = (aData->Count() == 2 ? scaleX :
|
|
aData->Item(2));
|
|
|
|
ProcessScaleHelper(aMatrix,
|
|
scaleX.GetFloatValue(),
|
|
scaleY.GetFloatValue(),
|
|
1.0f);
|
|
}
|
|
|
|
/* Helper function that, given a set of angles, constructs the appropriate
|
|
* skew matrix.
|
|
*/
|
|
static void
|
|
ProcessSkewHelper(Matrix4x4& aMatrix, double aXAngle, double aYAngle)
|
|
{
|
|
aMatrix.SkewXY(aXAngle, aYAngle);
|
|
}
|
|
|
|
/* Function that converts a skewx transform into a matrix. */
|
|
static void
|
|
ProcessSkewX(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_ASSERTION(aData->Count() == 2, "Bad array!");
|
|
ProcessSkewHelper(aMatrix, aData->Item(1).GetAngleValueInRadians(), 0.0);
|
|
}
|
|
|
|
/* Function that converts a skewy transform into a matrix. */
|
|
static void
|
|
ProcessSkewY(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_ASSERTION(aData->Count() == 2, "Bad array!");
|
|
ProcessSkewHelper(aMatrix, 0.0, aData->Item(1).GetAngleValueInRadians());
|
|
}
|
|
|
|
/* Function that converts a skew transform into a matrix. */
|
|
static void
|
|
ProcessSkew(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_ASSERTION(aData->Count() == 2 || aData->Count() == 3, "Bad array!");
|
|
|
|
double xSkew = aData->Item(1).GetAngleValueInRadians();
|
|
double ySkew = (aData->Count() == 2
|
|
? 0.0 : aData->Item(2).GetAngleValueInRadians());
|
|
|
|
ProcessSkewHelper(aMatrix, xSkew, ySkew);
|
|
}
|
|
|
|
/* Function that converts a rotate transform into a matrix. */
|
|
static void
|
|
ProcessRotateZ(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Invalid array!");
|
|
double theta = aData->Item(1).GetAngleValueInRadians();
|
|
aMatrix.RotateZ(theta);
|
|
}
|
|
|
|
static void
|
|
ProcessRotateX(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Invalid array!");
|
|
double theta = aData->Item(1).GetAngleValueInRadians();
|
|
aMatrix.RotateX(theta);
|
|
}
|
|
|
|
static void
|
|
ProcessRotateY(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Invalid array!");
|
|
double theta = aData->Item(1).GetAngleValueInRadians();
|
|
aMatrix.RotateY(theta);
|
|
}
|
|
|
|
static void
|
|
ProcessRotate3D(Matrix4x4& aMatrix, const nsCSSValue::Array* aData)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 5, "Invalid array!");
|
|
|
|
double theta = aData->Item(4).GetAngleValueInRadians();
|
|
float x = aData->Item(1).GetFloatValue();
|
|
float y = aData->Item(2).GetFloatValue();
|
|
float z = aData->Item(3).GetFloatValue();
|
|
|
|
Matrix4x4 temp;
|
|
temp.SetRotateAxisAngle(x, y, z, theta);
|
|
|
|
aMatrix = temp * aMatrix;
|
|
}
|
|
|
|
static void
|
|
ProcessPerspective(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array* aData,
|
|
nsStyleContext *aContext,
|
|
nsPresContext *aPresContext,
|
|
RuleNodeCacheConditions& aConditions)
|
|
{
|
|
NS_PRECONDITION(aData->Count() == 2, "Invalid array!");
|
|
|
|
float depth = ProcessTranslatePart(aData->Item(1), aContext,
|
|
aPresContext, aConditions, nullptr);
|
|
ApplyPerspectiveToMatrix(aMatrix, depth);
|
|
}
|
|
|
|
|
|
/**
|
|
* SetToTransformFunction is essentially a giant switch statement that fans
|
|
* out to many smaller helper functions.
|
|
*/
|
|
static void
|
|
MatrixForTransformFunction(Matrix4x4& aMatrix,
|
|
const nsCSSValue::Array * aData,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox,
|
|
bool* aContains3dTransform)
|
|
{
|
|
MOZ_ASSERT(aContains3dTransform);
|
|
NS_PRECONDITION(aData, "Why did you want to get data from a null array?");
|
|
// It's OK if aContext and aPresContext are null if the caller already
|
|
// knows that all length units have been converted to pixels (as
|
|
// StyleAnimationValue does).
|
|
|
|
|
|
/* Get the keyword for the transform. */
|
|
switch (TransformFunctionOf(aData)) {
|
|
case eCSSKeyword_translatex:
|
|
ProcessTranslateX(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox);
|
|
break;
|
|
case eCSSKeyword_translatey:
|
|
ProcessTranslateY(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox);
|
|
break;
|
|
case eCSSKeyword_translatez:
|
|
*aContains3dTransform = true;
|
|
ProcessTranslateZ(aMatrix, aData, aContext, aPresContext,
|
|
aConditions);
|
|
break;
|
|
case eCSSKeyword_translate:
|
|
ProcessTranslate(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox);
|
|
break;
|
|
case eCSSKeyword_translate3d:
|
|
*aContains3dTransform = true;
|
|
ProcessTranslate3D(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox);
|
|
break;
|
|
case eCSSKeyword_scalex:
|
|
ProcessScaleX(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_scaley:
|
|
ProcessScaleY(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_scalez:
|
|
*aContains3dTransform = true;
|
|
ProcessScaleZ(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_scale:
|
|
ProcessScale(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_scale3d:
|
|
*aContains3dTransform = true;
|
|
ProcessScale3D(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_skewx:
|
|
ProcessSkewX(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_skewy:
|
|
ProcessSkewY(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_skew:
|
|
ProcessSkew(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_rotatex:
|
|
*aContains3dTransform = true;
|
|
ProcessRotateX(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_rotatey:
|
|
*aContains3dTransform = true;
|
|
ProcessRotateY(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_rotatez:
|
|
*aContains3dTransform = true;
|
|
MOZ_FALLTHROUGH;
|
|
case eCSSKeyword_rotate:
|
|
ProcessRotateZ(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_rotate3d:
|
|
*aContains3dTransform = true;
|
|
ProcessRotate3D(aMatrix, aData);
|
|
break;
|
|
case eCSSKeyword_matrix:
|
|
ProcessMatrix(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox);
|
|
break;
|
|
case eCSSKeyword_matrix3d:
|
|
*aContains3dTransform = true;
|
|
ProcessMatrix3D(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox);
|
|
break;
|
|
case eCSSKeyword_interpolatematrix:
|
|
ProcessMatrixOperator<Interpolate>(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox,
|
|
aContains3dTransform);
|
|
break;
|
|
case eCSSKeyword_accumulatematrix:
|
|
ProcessMatrixOperator<Accumulate>(aMatrix, aData, aContext, aPresContext,
|
|
aConditions, aRefBox,
|
|
aContains3dTransform);
|
|
break;
|
|
case eCSSKeyword_perspective:
|
|
*aContains3dTransform = true;
|
|
ProcessPerspective(aMatrix, aData, aContext, aPresContext,
|
|
aConditions);
|
|
break;
|
|
default:
|
|
NS_NOTREACHED("Unknown transform function!");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return the transform function, as an nsCSSKeyword, for the given
|
|
* nsCSSValue::Array from a transform list.
|
|
*/
|
|
nsCSSKeyword
|
|
TransformFunctionOf(const nsCSSValue::Array* aData)
|
|
{
|
|
MOZ_ASSERT(aData->Item(0).GetUnit() == eCSSUnit_Enumerated);
|
|
return aData->Item(0).GetKeywordValue();
|
|
}
|
|
|
|
void
|
|
SetIdentityMatrix(nsCSSValue::Array* aMatrix)
|
|
{
|
|
MOZ_ASSERT(aMatrix, "aMatrix should be non-null");
|
|
|
|
nsCSSKeyword tfunc = TransformFunctionOf(aMatrix);
|
|
MOZ_ASSERT(tfunc == eCSSKeyword_matrix ||
|
|
tfunc == eCSSKeyword_matrix3d,
|
|
"Only accept matrix and matrix3d");
|
|
|
|
if (tfunc == eCSSKeyword_matrix) {
|
|
MOZ_ASSERT(aMatrix->Count() == 7, "Invalid matrix");
|
|
Matrix m;
|
|
for (size_t i = 0; i < 6; ++i) {
|
|
aMatrix->Item(i + 1).SetFloatValue(m.components[i], eCSSUnit_Number);
|
|
}
|
|
return;
|
|
}
|
|
|
|
MOZ_ASSERT(aMatrix->Count() == 17, "Invalid matrix3d");
|
|
Matrix4x4 m;
|
|
for (size_t i = 0; i < 16; ++i) {
|
|
aMatrix->Item(i + 1).SetFloatValue(m.components[i], eCSSUnit_Number);
|
|
}
|
|
}
|
|
|
|
Matrix4x4
|
|
ReadTransforms(const nsCSSValueList* aList,
|
|
nsStyleContext* aContext,
|
|
nsPresContext* aPresContext,
|
|
RuleNodeCacheConditions& aConditions,
|
|
TransformReferenceBox& aRefBox,
|
|
float aAppUnitsPerMatrixUnit,
|
|
bool* aContains3dTransform)
|
|
{
|
|
Matrix4x4 result;
|
|
|
|
for (const nsCSSValueList* curr = aList; curr != nullptr; curr = curr->mNext) {
|
|
const nsCSSValue &currElem = curr->mValue;
|
|
if (currElem.GetUnit() != eCSSUnit_Function) {
|
|
NS_ASSERTION(currElem.GetUnit() == eCSSUnit_None &&
|
|
!aList->mNext,
|
|
"stream should either be a list of functions or a "
|
|
"lone None");
|
|
continue;
|
|
}
|
|
NS_ASSERTION(currElem.GetArrayValue()->Count() >= 1,
|
|
"Incoming function is too short!");
|
|
|
|
/* Read in a single transform matrix. */
|
|
MatrixForTransformFunction(result, currElem.GetArrayValue(), aContext,
|
|
aPresContext, aConditions, aRefBox,
|
|
aContains3dTransform);
|
|
}
|
|
|
|
float scale = float(nsPresContext::AppUnitsPerCSSPixel()) / aAppUnitsPerMatrixUnit;
|
|
result.PreScale(1/scale, 1/scale, 1/scale);
|
|
result.PostScale(scale, scale, scale);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* The relevant section of the transitions specification:
|
|
* http://dev.w3.org/csswg/css3-transitions/#animation-of-property-types-
|
|
* defers all of the details to the 2-D and 3-D transforms specifications.
|
|
* For the 2-D transforms specification (all that's relevant for us, right
|
|
* now), the relevant section is:
|
|
* http://dev.w3.org/csswg/css3-2d-transforms/#animation
|
|
* This, in turn, refers to the unmatrix program in Graphics Gems,
|
|
* available from http://tog.acm.org/resources/GraphicsGems/ , and in
|
|
* particular as the file GraphicsGems/gemsii/unmatrix.c
|
|
* in http://tog.acm.org/resources/GraphicsGems/AllGems.tar.gz
|
|
*
|
|
* The unmatrix reference is for general 3-D transform matrices (any of the
|
|
* 16 components can have any value).
|
|
*
|
|
* For CSS 2-D transforms, we have a 2-D matrix with the bottom row constant:
|
|
*
|
|
* [ A C E ]
|
|
* [ B D F ]
|
|
* [ 0 0 1 ]
|
|
*
|
|
* For that case, I believe the algorithm in unmatrix reduces to:
|
|
*
|
|
* (1) If A * D - B * C == 0, the matrix is singular. Fail.
|
|
*
|
|
* (2) Set translation components (Tx and Ty) to the translation parts of
|
|
* the matrix (E and F) and then ignore them for the rest of the time.
|
|
* (For us, E and F each actually consist of three constants: a
|
|
* length, a multiplier for the width, and a multiplier for the
|
|
* height. This actually requires its own decomposition, but I'll
|
|
* keep that separate.)
|
|
*
|
|
* (3) Let the X scale (Sx) be sqrt(A^2 + B^2). Then divide both A and B
|
|
* by it.
|
|
*
|
|
* (4) Let the XY shear (K) be A * C + B * D. From C, subtract A times
|
|
* the XY shear. From D, subtract B times the XY shear.
|
|
*
|
|
* (5) Let the Y scale (Sy) be sqrt(C^2 + D^2). Divide C, D, and the XY
|
|
* shear (K) by it.
|
|
*
|
|
* (6) At this point, A * D - B * C is either 1 or -1. If it is -1,
|
|
* negate the XY shear (K), the X scale (Sx), and A, B, C, and D.
|
|
* (Alternatively, we could negate the XY shear (K) and the Y scale
|
|
* (Sy).)
|
|
*
|
|
* (7) Let the rotation be R = atan2(B, A).
|
|
*
|
|
* Then the resulting decomposed transformation is:
|
|
*
|
|
* translate(Tx, Ty) rotate(R) skewX(atan(K)) scale(Sx, Sy)
|
|
*
|
|
* An interesting result of this is that all of the simple transform
|
|
* functions (i.e., all functions other than matrix()), in isolation,
|
|
* decompose back to themselves except for:
|
|
* 'skewY(φ)', which is 'matrix(1, tan(φ), 0, 1, 0, 0)', which decomposes
|
|
* to 'rotate(φ) skewX(φ) scale(sec(φ), cos(φ))' since (ignoring the
|
|
* alternate sign possibilities that would get fixed in step 6):
|
|
* In step 3, the X scale factor is sqrt(1+tan²(φ)) = sqrt(sec²(φ)) = sec(φ).
|
|
* Thus, after step 3, A = 1/sec(φ) = cos(φ) and B = tan(φ) / sec(φ) = sin(φ).
|
|
* In step 4, the XY shear is sin(φ).
|
|
* Thus, after step 4, C = -cos(φ)sin(φ) and D = 1 - sin²(φ) = cos²(φ).
|
|
* Thus, in step 5, the Y scale is sqrt(cos²(φ)(sin²(φ) + cos²(φ)) = cos(φ).
|
|
* Thus, after step 5, C = -sin(φ), D = cos(φ), and the XY shear is tan(φ).
|
|
* Thus, in step 6, A * D - B * C = cos²(φ) + sin²(φ) = 1.
|
|
* In step 7, the rotation is thus φ.
|
|
*
|
|
* skew(θ, φ), which is matrix(1, tan(φ), tan(θ), 1, 0, 0), which decomposes
|
|
* to 'rotate(φ) skewX(θ + φ) scale(sec(φ), cos(φ))' since (ignoring
|
|
* the alternate sign possibilities that would get fixed in step 6):
|
|
* In step 3, the X scale factor is sqrt(1+tan²(φ)) = sqrt(sec²(φ)) = sec(φ).
|
|
* Thus, after step 3, A = 1/sec(φ) = cos(φ) and B = tan(φ) / sec(φ) = sin(φ).
|
|
* In step 4, the XY shear is cos(φ)tan(θ) + sin(φ).
|
|
* Thus, after step 4,
|
|
* C = tan(θ) - cos(φ)(cos(φ)tan(θ) + sin(φ)) = tan(θ)sin²(φ) - cos(φ)sin(φ)
|
|
* D = 1 - sin(φ)(cos(φ)tan(θ) + sin(φ)) = cos²(φ) - sin(φ)cos(φ)tan(θ)
|
|
* Thus, in step 5, the Y scale is sqrt(C² + D²) =
|
|
* sqrt(tan²(θ)(sin⁴(φ) + sin²(φ)cos²(φ)) -
|
|
* 2 tan(θ)(sin³(φ)cos(φ) + sin(φ)cos³(φ)) +
|
|
* (sin²(φ)cos²(φ) + cos⁴(φ))) =
|
|
* sqrt(tan²(θ)sin²(φ) - 2 tan(θ)sin(φ)cos(φ) + cos²(φ)) =
|
|
* cos(φ) - tan(θ)sin(φ) (taking the negative of the obvious solution so
|
|
* we avoid flipping in step 6).
|
|
* After step 5, C = -sin(φ) and D = cos(φ), and the XY shear is
|
|
* (cos(φ)tan(θ) + sin(φ)) / (cos(φ) - tan(θ)sin(φ)) =
|
|
* (dividing both numerator and denominator by cos(φ))
|
|
* (tan(θ) + tan(φ)) / (1 - tan(θ)tan(φ)) = tan(θ + φ).
|
|
* (See http://en.wikipedia.org/wiki/List_of_trigonometric_identities .)
|
|
* Thus, in step 6, A * D - B * C = cos²(φ) + sin²(φ) = 1.
|
|
* In step 7, the rotation is thus φ.
|
|
*
|
|
* To check this result, we can multiply things back together:
|
|
*
|
|
* [ cos(φ) -sin(φ) ] [ 1 tan(θ + φ) ] [ sec(φ) 0 ]
|
|
* [ sin(φ) cos(φ) ] [ 0 1 ] [ 0 cos(φ) ]
|
|
*
|
|
* [ cos(φ) cos(φ)tan(θ + φ) - sin(φ) ] [ sec(φ) 0 ]
|
|
* [ sin(φ) sin(φ)tan(θ + φ) + cos(φ) ] [ 0 cos(φ) ]
|
|
*
|
|
* but since tan(θ + φ) = (tan(θ) + tan(φ)) / (1 - tan(θ)tan(φ)),
|
|
* cos(φ)tan(θ + φ) - sin(φ)
|
|
* = cos(φ)(tan(θ) + tan(φ)) - sin(φ) + sin(φ)tan(θ)tan(φ)
|
|
* = cos(φ)tan(θ) + sin(φ) - sin(φ) + sin(φ)tan(θ)tan(φ)
|
|
* = cos(φ)tan(θ) + sin(φ)tan(θ)tan(φ)
|
|
* = tan(θ) (cos(φ) + sin(φ)tan(φ))
|
|
* = tan(θ) sec(φ) (cos²(φ) + sin²(φ))
|
|
* = tan(θ) sec(φ)
|
|
* and
|
|
* sin(φ)tan(θ + φ) + cos(φ)
|
|
* = sin(φ)(tan(θ) + tan(φ)) + cos(φ) - cos(φ)tan(θ)tan(φ)
|
|
* = tan(θ) (sin(φ) - sin(φ)) + sin(φ)tan(φ) + cos(φ)
|
|
* = sec(φ) (sin²(φ) + cos²(φ))
|
|
* = sec(φ)
|
|
* so the above is:
|
|
* [ cos(φ) tan(θ) sec(φ) ] [ sec(φ) 0 ]
|
|
* [ sin(φ) sec(φ) ] [ 0 cos(φ) ]
|
|
*
|
|
* [ 1 tan(θ) ]
|
|
* [ tan(φ) 1 ]
|
|
*/
|
|
|
|
/*
|
|
* Decompose2DMatrix implements the above decomposition algorithm.
|
|
*/
|
|
|
|
bool
|
|
Decompose2DMatrix(const Matrix& aMatrix,
|
|
Point3D& aScale,
|
|
ShearArray& aShear,
|
|
gfxQuaternion& aRotate,
|
|
Point3D& aTranslate)
|
|
{
|
|
float A = aMatrix._11,
|
|
B = aMatrix._12,
|
|
C = aMatrix._21,
|
|
D = aMatrix._22;
|
|
if (A * D == B * C) {
|
|
// singular matrix
|
|
return false;
|
|
}
|
|
|
|
float scaleX = sqrt(A * A + B * B);
|
|
A /= scaleX;
|
|
B /= scaleX;
|
|
|
|
float XYshear = A * C + B * D;
|
|
C -= A * XYshear;
|
|
D -= B * XYshear;
|
|
|
|
float scaleY = sqrt(C * C + D * D);
|
|
C /= scaleY;
|
|
D /= scaleY;
|
|
XYshear /= scaleY;
|
|
|
|
// A*D - B*C should now be 1 or -1
|
|
NS_ASSERTION(0.99 < Abs(A*D - B*C) && Abs(A*D - B*C) < 1.01,
|
|
"determinant should now be 1 or -1");
|
|
if (A * D < B * C) {
|
|
A = -A;
|
|
B = -B;
|
|
C = -C;
|
|
D = -D;
|
|
XYshear = -XYshear;
|
|
scaleX = -scaleX;
|
|
}
|
|
|
|
float rotate = atan2f(B, A);
|
|
aRotate = gfxQuaternion(0, 0, sin(rotate/2), cos(rotate/2));
|
|
aShear[ShearType::XYSHEAR] = XYshear;
|
|
aScale.x = scaleX;
|
|
aScale.y = scaleY;
|
|
aTranslate.x = aMatrix._31;
|
|
aTranslate.y = aMatrix._32;
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Implementation of the unmatrix algorithm, specified by:
|
|
*
|
|
* http://dev.w3.org/csswg/css3-2d-transforms/#unmatrix
|
|
*
|
|
* This, in turn, refers to the unmatrix program in Graphics Gems,
|
|
* available from http://tog.acm.org/resources/GraphicsGems/ , and in
|
|
* particular as the file GraphicsGems/gemsii/unmatrix.c
|
|
* in http://tog.acm.org/resources/GraphicsGems/AllGems.tar.gz
|
|
*/
|
|
bool
|
|
Decompose3DMatrix(const Matrix4x4& aMatrix,
|
|
Point3D& aScale,
|
|
ShearArray& aShear,
|
|
gfxQuaternion& aRotate,
|
|
Point3D& aTranslate,
|
|
Point4D& aPerspective)
|
|
{
|
|
Matrix4x4 local = aMatrix;
|
|
|
|
if (local[3][3] == 0) {
|
|
return false;
|
|
}
|
|
/* Normalize the matrix */
|
|
local.Normalize();
|
|
|
|
/**
|
|
* perspective is used to solve for perspective, but it also provides
|
|
* an easy way to test for singularity of the upper 3x3 component.
|
|
*/
|
|
Matrix4x4 perspective = local;
|
|
Point4D empty(0, 0, 0, 1);
|
|
perspective.SetTransposedVector(3, empty);
|
|
|
|
if (perspective.Determinant() == 0.0) {
|
|
return false;
|
|
}
|
|
|
|
/* First, isolate perspective. */
|
|
if (local[0][3] != 0 || local[1][3] != 0 ||
|
|
local[2][3] != 0) {
|
|
/* aPerspective is the right hand side of the equation. */
|
|
aPerspective = local.TransposedVector(3);
|
|
|
|
/**
|
|
* Solve the equation by inverting perspective and multiplying
|
|
* aPerspective by the inverse.
|
|
*/
|
|
perspective.Invert();
|
|
aPerspective = perspective.TransposeTransform4D(aPerspective);
|
|
|
|
/* Clear the perspective partition */
|
|
local.SetTransposedVector(3, empty);
|
|
} else {
|
|
aPerspective = Point4D(0, 0, 0, 1);
|
|
}
|
|
|
|
/* Next take care of translation */
|
|
for (int i = 0; i < 3; i++) {
|
|
aTranslate[i] = local[3][i];
|
|
local[3][i] = 0;
|
|
}
|
|
|
|
/* Now get scale and shear. */
|
|
|
|
/* Compute X scale factor and normalize first row. */
|
|
aScale.x = local[0].Length();
|
|
local[0] /= aScale.x;
|
|
|
|
/* Compute XY shear factor and make 2nd local orthogonal to 1st. */
|
|
aShear[ShearType::XYSHEAR] = local[0].DotProduct(local[1]);
|
|
local[1] -= local[0] * aShear[ShearType::XYSHEAR];
|
|
|
|
/* Now, compute Y scale and normalize 2nd local. */
|
|
aScale.y = local[1].Length();
|
|
local[1] /= aScale.y;
|
|
aShear[ShearType::XYSHEAR] /= aScale.y;
|
|
|
|
/* Compute XZ and YZ shears, make 3rd local orthogonal */
|
|
aShear[ShearType::XZSHEAR] = local[0].DotProduct(local[2]);
|
|
local[2] -= local[0] * aShear[ShearType::XZSHEAR];
|
|
aShear[ShearType::YZSHEAR] = local[1].DotProduct(local[2]);
|
|
local[2] -= local[1] * aShear[ShearType::YZSHEAR];
|
|
|
|
/* Next, get Z scale and normalize 3rd local. */
|
|
aScale.z = local[2].Length();
|
|
local[2] /= aScale.z;
|
|
|
|
aShear[ShearType::XZSHEAR] /= aScale.z;
|
|
aShear[ShearType::YZSHEAR] /= aScale.z;
|
|
|
|
/**
|
|
* At this point, the matrix (in locals) is orthonormal.
|
|
* Check for a coordinate system flip. If the determinant
|
|
* is -1, then negate the matrix and the scaling factors.
|
|
*/
|
|
if (local[0].DotProduct(local[1].CrossProduct(local[2])) < 0) {
|
|
aScale *= -1;
|
|
for (int i = 0; i < 3; i++) {
|
|
local[i] *= -1;
|
|
}
|
|
}
|
|
|
|
/* Now, get the rotations out */
|
|
aRotate = gfxQuaternion(local);
|
|
|
|
return true;
|
|
}
|
|
|
|
Matrix
|
|
CSSValueArrayTo2DMatrix(nsCSSValue::Array* aArray)
|
|
{
|
|
MOZ_ASSERT(aArray &&
|
|
TransformFunctionOf(aArray) == eCSSKeyword_matrix &&
|
|
aArray->Count() == 7);
|
|
Matrix m(aArray->Item(1).GetFloatValue(),
|
|
aArray->Item(2).GetFloatValue(),
|
|
aArray->Item(3).GetFloatValue(),
|
|
aArray->Item(4).GetFloatValue(),
|
|
aArray->Item(5).GetFloatValue(),
|
|
aArray->Item(6).GetFloatValue());
|
|
return m;
|
|
}
|
|
|
|
Matrix4x4
|
|
CSSValueArrayTo3DMatrix(nsCSSValue::Array* aArray)
|
|
{
|
|
MOZ_ASSERT(aArray &&
|
|
TransformFunctionOf(aArray) == eCSSKeyword_matrix3d &&
|
|
aArray->Count() == 17);
|
|
gfx::Float array[16];
|
|
for (size_t i = 0; i < 16; ++i) {
|
|
array[i] = aArray->Item(i+1).GetFloatValue();
|
|
}
|
|
Matrix4x4 m(array);
|
|
return m;
|
|
}
|
|
|
|
gfxSize
|
|
GetScaleValue(const nsCSSValueSharedList* aList,
|
|
const nsIFrame* aForFrame)
|
|
{
|
|
MOZ_ASSERT(aList && aList->mHead);
|
|
MOZ_ASSERT(aForFrame);
|
|
|
|
RuleNodeCacheConditions dontCare;
|
|
bool dontCareBool;
|
|
TransformReferenceBox refBox(aForFrame);
|
|
Matrix4x4 transform = ReadTransforms(
|
|
aList->mHead,
|
|
aForFrame->StyleContext(),
|
|
aForFrame->PresContext(), dontCare, refBox,
|
|
aForFrame->PresContext()->AppUnitsPerDevPixel(),
|
|
&dontCareBool);
|
|
Matrix transform2d;
|
|
bool canDraw2D = transform.CanDraw2D(&transform2d);
|
|
if (!canDraw2D) {
|
|
return gfxSize();
|
|
}
|
|
|
|
return ThebesMatrix(transform2d).ScaleFactors(true);
|
|
}
|
|
|
|
} // namespace nsStyleTransformMatrix
|