diff -r 000000000000 -r 6474c204b198 layout/style/nsStyleTransformMatrix.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/style/nsStyleTransformMatrix.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,71 @@
+/* -*- 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 representing three matrices that can be used for style transforms.
+ */
+
+#ifndef nsStyleTransformMatrix_h_
+#define nsStyleTransformMatrix_h_
+
+#include "nsCSSValue.h"
+#include "gfx3DMatrix.h"
+
+class nsStyleContext;
+class nsPresContext;
+struct nsRect;
+
+/**
+ * A helper to generate gfxMatrixes from css transform functions.
+ */
+namespace nsStyleTransformMatrix {
+  
+  /**
+   * Return the transform function, as an nsCSSKeyword, for the given
+   * nsCSSValue::Array from a transform list.
+   */
+  nsCSSKeyword TransformFunctionOf(const nsCSSValue::Array* aData);
+
+  float ProcessTranslatePart(const nsCSSValue& aValue,
+                             nsStyleContext* aContext,
+                             nsPresContext* aPresContext,
+                             bool& aCanStoreInRuleTree,
+                             nscoord aSize,
+                             float aAppUnitsPerMatrixUnit);
+
+  void
+  ProcessInterpolateMatrix(gfx3DMatrix& aMatrix,
+                            const nsCSSValue::Array* aData,
+                            nsStyleContext* aContext,
+                            nsPresContext* aPresContext,
+                            bool& aCanStoreInRuleTree,
+                            nsRect& aBounds, float aAppUnitsPerMatrixUnit);
+
+  /**
+   * Given an nsCSSValueList containing -moz-transform functions,
+   * returns a matrix containing the value of those functions.
+   *
+   * @param aData The nsCSSValueList containing the transform functions
+   * @param aContext The style context, used for unit conversion.
+   * @param aPresContext The presentation context, used for unit conversion.
+   * @param aCanStoreInRuleTree Set to false if the result cannot be cached
+   *                            in the rule tree, otherwise untouched.
+   * @param aBounds The frame's bounding rectangle.
+   * @param aAppUnitsPerMatrixUnit The number of app units per device pixel.
+   *
+   * aContext and aPresContext may be null if all of the (non-percent)
+   * length values in aData are already known to have been converted to
+   * eCSSUnit_Pixel (as they are in an nsStyleAnimation::Value)
+   */
+  gfx3DMatrix ReadTransforms(const nsCSSValueList* aList,
+                             nsStyleContext* aContext,
+                             nsPresContext* aPresContext,
+                             bool &aCanStoreInRuleTree,
+                             nsRect& aBounds,
+                             float aAppUnitsPerMatrixUnit);
+
+} // namespace nsStyleTransformMatrix
+
+#endif