| // Copyright 2011 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef CC_INPUT_PAGE_SCALE_ANIMATION_H_ |
| #define CC_INPUT_PAGE_SCALE_ANIMATION_H_ |
| |
| #include "base/basictypes.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "ui/gfx/size.h" |
| #include "ui/gfx/vector2d_f.h" |
| |
| namespace cc { |
| class TimingFunction; |
| |
| // A small helper class that does the math for zoom animations, primarily for |
| // double-tap zoom. Initialize it with starting and ending scroll/page scale |
| // positions and an animation length time, then call ...AtTime() at every frame |
| // to obtain the current interpolated position. The supplied timing function |
| // is used to ease the animation. |
| // |
| // All sizes and vectors in this class's public methods are in the root scroll |
| // layer's coordinate space. |
| class PageScaleAnimation { |
| public: |
| // Construct with the state at the beginning of the animation. |
| static scoped_ptr<PageScaleAnimation> Create( |
| gfx::Vector2dF start_scroll_offset, |
| float start_page_scale_factor, |
| gfx::SizeF viewport_size, |
| gfx::SizeF root_layer_size, |
| double start_time, |
| scoped_ptr<TimingFunction> timing_function); |
| |
| ~PageScaleAnimation(); |
| |
| // The following methods initialize the animation. Call one of them |
| // immediately after construction to set the final scroll and page scale. |
| |
| // Zoom while explicitly specifying the top-left scroll position. |
| void ZoomTo(gfx::Vector2dF target_scroll_offset, |
| float target_page_scale_factor, |
| double duration); |
| |
| // Zoom based on a specified anchor. The animator will attempt to keep it |
| // at the same position on the physical display throughout the animation, |
| // unless the edges of the root layer are hit. The anchor is specified |
| // as an offset from the content layer. |
| void ZoomWithAnchor(gfx::Vector2dF anchor, |
| float target_page_scale_factor, |
| double duration); |
| |
| // Call these functions while the animation is in progress to output the |
| // current state. |
| gfx::Vector2dF ScrollOffsetAtTime(double time) const; |
| float PageScaleFactorAtTime(double time) const; |
| bool IsAnimationCompleteAtTime(double time) const; |
| |
| // The following methods return state which is invariant throughout the |
| // course of the animation. |
| double start_time() const { return start_time_; } |
| double duration() const { return duration_; } |
| double end_time() const { return start_time_ + duration_; } |
| gfx::Vector2dF target_scroll_offset() const { return target_scroll_offset_; } |
| float target_page_scale_factor() const { return target_page_scale_factor_; } |
| |
| protected: |
| PageScaleAnimation(gfx::Vector2dF start_scroll_offset, |
| float start_page_scale_factor, |
| gfx::SizeF viewport_size, |
| gfx::SizeF root_layer_size, |
| double start_time, |
| scoped_ptr<TimingFunction> timing_function); |
| |
| private: |
| void ClampTargetScrollOffset(); |
| void InferTargetScrollOffsetFromStartAnchor(); |
| void InferTargetAnchorFromScrollOffsets(); |
| |
| gfx::SizeF StartViewportSize() const; |
| gfx::SizeF TargetViewportSize() const; |
| float InterpAtTime(double time) const; |
| gfx::SizeF ViewportSizeAt(float interp) const; |
| gfx::Vector2dF ScrollOffsetAt(float interp) const; |
| gfx::Vector2dF AnchorAt(float interp) const; |
| gfx::Vector2dF ViewportRelativeAnchorAt(float interp) const; |
| float PageScaleFactorAt(float interp) const; |
| |
| float start_page_scale_factor_; |
| float target_page_scale_factor_; |
| gfx::Vector2dF start_scroll_offset_; |
| gfx::Vector2dF target_scroll_offset_; |
| |
| gfx::Vector2dF start_anchor_; |
| gfx::Vector2dF target_anchor_; |
| |
| gfx::SizeF viewport_size_; |
| gfx::SizeF root_layer_size_; |
| |
| double start_time_; |
| double duration_; |
| |
| scoped_ptr<TimingFunction> timing_function_; |
| |
| DISALLOW_COPY_AND_ASSIGN(PageScaleAnimation); |
| }; |
| |
| } // namespace cc |
| |
| #endif // CC_INPUT_PAGE_SCALE_ANIMATION_H_ |