/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ /* * A class used for intermediate representations of the -moz-transform property. */ #include "nsStyleTransformMatrix.h" #include "nsCSSValue.h" #include "nsPresContext.h" #include "nsRuleNode.h" #include "nsCSSKeywords.h" #include "nsStyleAnimation.h" namespace css = mozilla::css; namespace nsStyleTransformMatrix { /* Note on floating point precision: The transform matrix is an array * of single precision 'float's, and so are most of the input values * we get from the style system, but intermediate calculations * involving angles need to be done in 'double'. */ /* Force small values to zero. We do this to avoid having sin(360deg) * evaluate to a tiny but nonzero value. */ static double FlushToZero(double aVal) { if (-FLT_EPSILON < aVal && aVal < FLT_EPSILON) return 0.0f; else return aVal; } float ProcessTranslatePart(const nsCSSValue& aValue, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nscoord aSize, float aAppUnitsPerMatrixUnit) { nscoord offset = 0; float percent = 0.0f; if (aValue.GetUnit() == eCSSUnit_Percent) { percent = aValue.GetPercentValue(); } else if (aValue.GetUnit() == eCSSUnit_Pixel || aValue.GetUnit() == eCSSUnit_Number) { // Handle this here (even though nsRuleNode::CalcLength handles it // fine) so that callers are allowed to pass a null style context // and pres context to SetToTransformFunction if they know (as // nsStyleAnimation does) that all lengths within the transform // function have already been computed to pixels and percents. // // Raw numbers are treated as being pixels. // // Don't convert to aValue to AppUnits here to avoid precision issues. return aValue.GetFloatValue() * (float(nsPresContext::AppUnitsPerCSSPixel()) / aAppUnitsPerMatrixUnit); } else if (aValue.IsCalcUnit()) { nsRuleNode::ComputedCalc result = nsRuleNode::SpecifiedCalcToComputedCalc(aValue, aContext, aPresContext, aCanStoreInRuleTree); percent = result.mPercent; offset = result.mLength; } else { offset = nsRuleNode::CalcLength(aValue, aContext, aPresContext, aCanStoreInRuleTree); } return (percent * NSAppUnitsToFloatPixels(aSize, aAppUnitsPerMatrixUnit)) + NSAppUnitsToFloatPixels(offset, aAppUnitsPerMatrixUnit); } /** * Helper functions to process all the transformation function types. * * These take a matrix parameter to accumulate the current matrix. */ /* Helper function to process a matrix entry. */ static void ProcessMatrix(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 7, "Invalid array!"); gfxMatrix result; /* Take the first four elements out of the array as floats and store * them. */ result.xx = aData->Item(1).GetFloatValue(); result.yx = aData->Item(2).GetFloatValue(); result.xy = aData->Item(3).GetFloatValue(); result.yy = aData->Item(4).GetFloatValue(); /* The last two elements have their length parts stored in aDelta * and their percent parts stored in aX[0] and aY[1]. */ result.x0 = ProcessTranslatePart(aData->Item(5), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Width(), aAppUnitsPerMatrixUnit); result.y0 = ProcessTranslatePart(aData->Item(6), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Height(), aAppUnitsPerMatrixUnit); aMatrix.PreMultiply(result); } static void ProcessMatrix3D(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 17, "Invalid array!"); gfx3DMatrix temp; temp._11 = aData->Item(1).GetFloatValue(); temp._12 = aData->Item(2).GetFloatValue(); temp._13 = aData->Item(3).GetFloatValue(); temp._14 = aData->Item(4).GetFloatValue(); temp._21 = aData->Item(5).GetFloatValue(); temp._22 = aData->Item(6).GetFloatValue(); temp._23 = aData->Item(7).GetFloatValue(); temp._24 = aData->Item(8).GetFloatValue(); temp._31 = aData->Item(9).GetFloatValue(); temp._32 = aData->Item(10).GetFloatValue(); temp._33 = aData->Item(11).GetFloatValue(); temp._34 = aData->Item(12).GetFloatValue(); temp._44 = aData->Item(16).GetFloatValue(); temp._41 = ProcessTranslatePart(aData->Item(13), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Width(), aAppUnitsPerMatrixUnit); temp._42 = ProcessTranslatePart(aData->Item(14), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Height(), aAppUnitsPerMatrixUnit); temp._43 = ProcessTranslatePart(aData->Item(15), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Height(), aAppUnitsPerMatrixUnit); aMatrix.PreMultiply(temp); } /* Helper function to process two matrices that we need to interpolate between */ void ProcessInterpolateMatrix(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 4, "Invalid array!"); gfx3DMatrix matrix1, matrix2; if (aData->Item(1).GetUnit() == eCSSUnit_List) { matrix1 = nsStyleTransformMatrix::ReadTransforms(aData->Item(1).GetListValue(), aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); } if (aData->Item(2).GetUnit() == eCSSUnit_List) { matrix2 = ReadTransforms(aData->Item(2).GetListValue(), aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); } double progress = aData->Item(3).GetPercentValue(); aMatrix = nsStyleAnimation::InterpolateTransformMatrix(matrix1, matrix2, progress) * aMatrix; } /* Helper function to process a translatex function. */ static void ProcessTranslateX(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 2, "Invalid array!"); gfxPoint3D temp; temp.x = ProcessTranslatePart(aData->Item(1), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Width(), aAppUnitsPerMatrixUnit); aMatrix.Translate(temp); } /* Helper function to process a translatey function. */ static void ProcessTranslateY(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 2, "Invalid array!"); gfxPoint3D temp; temp.y = ProcessTranslatePart(aData->Item(1), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Height(), aAppUnitsPerMatrixUnit); aMatrix.Translate(temp); } static void ProcessTranslateZ(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 2, "Invalid array!"); gfxPoint3D temp; temp.z = ProcessTranslatePart(aData->Item(1), aContext, aPresContext, aCanStoreInRuleTree, 0, aAppUnitsPerMatrixUnit); aMatrix.Translate(temp); } /* Helper function to process a translate function. */ static void ProcessTranslate(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 2 || aData->Count() == 3, "Invalid array!"); gfxPoint3D temp; temp.x = ProcessTranslatePart(aData->Item(1), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Width(), aAppUnitsPerMatrixUnit); /* If we read in a Y component, set it appropriately */ if (aData->Count() == 3) { temp.y = ProcessTranslatePart(aData->Item(2), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Height(), aAppUnitsPerMatrixUnit); } aMatrix.Translate(temp); } static void ProcessTranslate3D(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 4, "Invalid array!"); gfxPoint3D temp; temp.x = ProcessTranslatePart(aData->Item(1), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Width(), aAppUnitsPerMatrixUnit); temp.y = ProcessTranslatePart(aData->Item(2), aContext, aPresContext, aCanStoreInRuleTree, aBounds.Height(), aAppUnitsPerMatrixUnit); temp.z = ProcessTranslatePart(aData->Item(3), aContext, aPresContext, aCanStoreInRuleTree, 0, aAppUnitsPerMatrixUnit); aMatrix.Translate(temp); } /* Helper function to set up a scale matrix. */ static void ProcessScaleHelper(gfx3DMatrix& aMatrix, float aXScale, float aYScale, float aZScale) { aMatrix.Scale(aXScale, aYScale, aZScale); } /* Process a scalex function. */ static void ProcessScaleX(gfx3DMatrix& 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(gfx3DMatrix& 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(gfx3DMatrix& 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(gfx3DMatrix& 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(gfx3DMatrix& 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(gfx3DMatrix& aMatrix, double aXAngle, double aYAngle) { aMatrix.SkewXY(aXAngle, aYAngle); } /* Function that converts a skewx transform into a matrix. */ static void ProcessSkewX(gfx3DMatrix& 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(gfx3DMatrix& 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(gfx3DMatrix& 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(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData) { NS_PRECONDITION(aData->Count() == 2, "Invalid array!"); double theta = aData->Item(1).GetAngleValueInRadians(); aMatrix.RotateZ(theta); } static void ProcessRotateX(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData) { NS_PRECONDITION(aData->Count() == 2, "Invalid array!"); double theta = aData->Item(1).GetAngleValueInRadians(); aMatrix.RotateX(theta); } static void ProcessRotateY(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData) { NS_PRECONDITION(aData->Count() == 2, "Invalid array!"); double theta = aData->Item(1).GetAngleValueInRadians(); aMatrix.RotateY(theta); } static void ProcessRotate3D(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData) { NS_PRECONDITION(aData->Count() == 5, "Invalid array!"); /* We want our matrix to look like this: * | 1 + (1-cos(angle))*(x*x-1) -z*sin(angle)+(1-cos(angle))*x*y y*sin(angle)+(1-cos(angle))*x*z 0 | * | z*sin(angle)+(1-cos(angle))*x*y 1 + (1-cos(angle))*(y*y-1) -x*sin(angle)+(1-cos(angle))*y*z 0 | * | -y*sin(angle)+(1-cos(angle))*x*z x*sin(angle)+(1-cos(angle))*y*z 1 + (1-cos(angle))*(z*z-1) 0 | * | 0 0 0 1 | * (see http://www.w3.org/TR/css3-3d-transforms/#transform-functions) */ /* The current spec specifies a matrix that rotates in the wrong direction. For now we just negate * the angle provided to get the correct rotation direction until the spec is updated. * See bug 704468. */ double theta = -aData->Item(4).GetAngleValueInRadians(); float cosTheta = FlushToZero(cos(theta)); float sinTheta = FlushToZero(sin(theta)); float x = aData->Item(1).GetFloatValue(); float y = aData->Item(2).GetFloatValue(); float z = aData->Item(3).GetFloatValue(); /* Normalize [x,y,z] */ float length = sqrt(x*x + y*y + z*z); if (length == 0.0) { return; } x /= length; y /= length; z /= length; gfx3DMatrix temp; /* Create our matrix */ temp._11 = 1 + (1 - cosTheta) * (x * x - 1); temp._12 = -z * sinTheta + (1 - cosTheta) * x * y; temp._13 = y * sinTheta + (1 - cosTheta) * x * z; temp._14 = 0.0f; temp._21 = z * sinTheta + (1 - cosTheta) * x * y; temp._22 = 1 + (1 - cosTheta) * (y * y - 1); temp._23 = -x * sinTheta + (1 - cosTheta) * y * z; temp._24 = 0.0f; temp._31 = -y * sinTheta + (1 - cosTheta) * x * z; temp._32 = x * sinTheta + (1 - cosTheta) * y * z; temp._33 = 1 + (1 - cosTheta) * (z * z - 1); temp._34 = 0.0f; temp._41 = 0.0f; temp._42 = 0.0f; temp._43 = 0.0f; temp._44 = 1.0f; aMatrix = temp * aMatrix; } static void ProcessPerspective(gfx3DMatrix& aMatrix, const nsCSSValue::Array* aData, nsStyleContext *aContext, nsPresContext *aPresContext, bool &aCanStoreInRuleTree, float aAppUnitsPerMatrixUnit) { NS_PRECONDITION(aData->Count() == 2, "Invalid array!"); float depth = ProcessTranslatePart(aData->Item(1), aContext, aPresContext, aCanStoreInRuleTree, 0, aAppUnitsPerMatrixUnit); aMatrix.Perspective(depth); } /** * SetToTransformFunction is essentially a giant switch statement that fans * out to many smaller helper functions. */ static void MatrixForTransformFunction(gfx3DMatrix& aMatrix, const nsCSSValue::Array * aData, nsStyleContext* aContext, nsPresContext* aPresContext, bool& aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { 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 // nsStyleAnimation does). /* Get the keyword for the transform. */ switch (TransformFunctionOf(aData)) { case eCSSKeyword_translatex: ProcessTranslateX(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_translatey: ProcessTranslateY(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_translatez: ProcessTranslateZ(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_translate: ProcessTranslate(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_translate3d: ProcessTranslate3D(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_scalex: ProcessScaleX(aMatrix, aData); break; case eCSSKeyword_scaley: ProcessScaleY(aMatrix, aData); break; case eCSSKeyword_scalez: ProcessScaleZ(aMatrix, aData); break; case eCSSKeyword_scale: ProcessScale(aMatrix, aData); break; case eCSSKeyword_scale3d: 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: ProcessRotateX(aMatrix, aData); break; case eCSSKeyword_rotatey: ProcessRotateY(aMatrix, aData); break; case eCSSKeyword_rotatez: case eCSSKeyword_rotate: ProcessRotateZ(aMatrix, aData); break; case eCSSKeyword_rotate3d: ProcessRotate3D(aMatrix, aData); break; case eCSSKeyword_matrix: ProcessMatrix(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_matrix3d: ProcessMatrix3D(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_interpolatematrix: ProcessInterpolateMatrix(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); break; case eCSSKeyword_perspective: ProcessPerspective(aMatrix, aData, aContext, aPresContext, aCanStoreInRuleTree, aAppUnitsPerMatrixUnit); 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(); } gfx3DMatrix ReadTransforms(const nsCSSValueList* aList, nsStyleContext* aContext, nsPresContext* aPresContext, bool &aCanStoreInRuleTree, nsRect& aBounds, float aAppUnitsPerMatrixUnit) { gfx3DMatrix result; for (const nsCSSValueList* curr = aList; curr != nullptr; curr = curr->mNext) { const nsCSSValue &currElem = curr->mValue; NS_ASSERTION(currElem.GetUnit() == eCSSUnit_Function, "Stream should consist solely of functions!"); NS_ASSERTION(currElem.GetArrayValue()->Count() >= 1, "Incoming function is too short!"); /* Read in a single transform matrix. */ MatrixForTransformFunction(result, currElem.GetArrayValue(), aContext, aPresContext, aCanStoreInRuleTree, aBounds, aAppUnitsPerMatrixUnit); } return result; } } // namespace nsStyleTransformMatrix