1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CC_ANIMATION_TRANSFORM_OPERATIONS_H_ 6 #define CC_ANIMATION_TRANSFORM_OPERATIONS_H_ 7 8 #include <vector> 9 10 #include "base/memory/scoped_ptr.h" 11 #include "cc/animation/transform_operation.h" 12 #include "cc/base/cc_export.h" 13 #include "ui/gfx/transform.h" 14 15 namespace gfx { 16 struct DecomposedTransform; 17 } 18 19 namespace cc { 20 21 // Transform operations are a decomposed transformation matrix. It can be 22 // applied to obtain a gfx::Transform at any time, and can be blended 23 // intelligently with other transform operations, so long as they represent the 24 // same decomposition. For example, if we have a transform that is made up of 25 // a rotation followed by skew, it can be blended intelligently with another 26 // transform made up of a rotation followed by a skew. Blending is possible if 27 // we have two dissimilar sets of transform operations, but the effect may not 28 // be what was intended. For more information, see the comments for the blend 29 // function below. 30 class CC_EXPORT TransformOperations { 31 public: 32 TransformOperations(); 33 TransformOperations(const TransformOperations& other); 34 ~TransformOperations(); 35 36 // Returns a transformation matrix representing these transform operations. 37 gfx::Transform Apply() const; 38 39 // Given another set of transform operations and a progress in the range 40 // [0, 1], returns a transformation matrix representing the intermediate 41 // value. If this->MatchesTypes(from), then each of the operations are 42 // blended separately and then combined. Otherwise, the two sets of 43 // transforms are baked to matrices (using apply), and the matrices are 44 // then decomposed and interpolated. For more information, see 45 // http://www.w3.org/TR/2011/WD-css3-2d-transforms-20111215/#matrix-decomposition. 46 gfx::Transform Blend(const TransformOperations& from, double progress) const; 47 48 // Returns true if this operation and its descendants have the same types 49 // as other and its descendants. 50 bool MatchesTypes(const TransformOperations& other) const; 51 52 // Returns true if these operations can be blended. It will only return 53 // false if we must resort to matrix interpolation, and matrix interpolation 54 // fails (this can happen if either matrix cannot be decomposed). 55 bool CanBlendWith(const TransformOperations& other) const; 56 57 void AppendTranslate(double x, double y, double z); 58 void AppendRotate(double x, double y, double z, double degrees); 59 void AppendScale(double x, double y, double z); 60 void AppendSkew(double x, double y); 61 void AppendPerspective(double depth); 62 void AppendMatrix(const gfx::Transform& matrix); 63 void AppendIdentity(); 64 bool IsIdentity() const; 65 66 private: 67 bool BlendInternal(const TransformOperations& from, double progress, 68 gfx::Transform* result) const; 69 70 std::vector<TransformOperation> operations_; 71 72 bool ComputeDecomposedTransform() const; 73 74 // For efficiency, we cache the decomposed transform. 75 mutable scoped_ptr<gfx::DecomposedTransform> decomposed_transform_; 76 mutable bool decomposed_transform_dirty_; 77 78 DISALLOW_ASSIGN(TransformOperations); 79 }; 80 81 } // namespace cc 82 83 #endif // CC_ANIMATION_TRANSFORM_OPERATIONS_H_ 84
