cc: Compute the maximum scale of animations

This adds MaximumScale and HasOnlyTranslationTransforms
methods to LayerAnimationController. 

BUG=224913

Review URL: https://codereview.chromium.org/214003004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@261583 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 16 insertions, 0 deletions

diff --git a/cc/animation/transform_operations.h b/cc/animation/transform_operations.h
index 7d42cea..f086eb1 100644
--- a/cc/animation/transform_operations.h
+++ b/cc/animation/transform_operations.h
@@ -60,6 +60,17 @@ class CC_EXPORT TransformOperations {
   // Returns true if these operations affect scale.
   bool AffectsScale() const;
 
+  // Returns true if these operations are only translations.
+  bool IsTranslation() const;
+
+  // Sets |max_scale| to be the maximum scale in any dimension when calling
+  // Blend on |from| with progress in the range [min_progress, max_progress]. If
+  // this maximum scale cannot be computed, returns false.
+  bool MaximumScale(const TransformOperations& from,
+                    SkMScalar min_progress,
+                    SkMScalar max_progress,
+                    float* max_scale) const;
+
   // Returns true if this operation and its descendants have the same types
   // as other and its descendants.
   bool MatchesTypes(const TransformOperations& other) const;
@@ -87,6 +98,11 @@ class CC_EXPORT TransformOperations {
 
   bool ComputeDecomposedTransform() const;
 
+  // If these operations have no more than one scale operation, and if the only
+  // other operations are translations, sets |scale| to the scale component
+  // of these operations. Otherwise, returns false.
+  bool ScaleComponent(gfx::Vector3dF* scale) const;
+
   // For efficiency, we cache the decomposed transform.
   mutable scoped_ptr<gfx::DecomposedTransform> decomposed_transform_;
   mutable bool decomposed_transform_dirty_;