ui/gfx/interpolated_transform.h

   1 // Copyright (c) 2012 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 UI_GFX_INTERPOLATED_TRANSFORM_H_
   6 #define UI_GFX_INTERPOLATED_TRANSFORM_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "ui/gfx/point.h"
  11 #include "ui/gfx/point3_f.h"
  12 #include "ui/gfx/transform.h"
  13 #include "ui/gfx/transform_util.h"
  14 #include "ui/gfx/vector3d_f.h"
  15
  16 namespace ui {
  17
  18 ///////////////////////////////////////////////////////////////////////////////
  19 // class InterpolatedTransform
  20 //
  21 // Abstract base class for transforms that animate over time. These
  22 // interpolated transforms can be combined to allow for more sophisticated
  23 // animations. For example, you might combine a rotation of 90 degrees between
  24 // times 0 and 1, with a scale from 1 to 0.3 between times 0 and 0.25 and a
  25 // scale from 0.3 to 1 from between times 0.75 and 1.
  26 //
  27 ///////////////////////////////////////////////////////////////////////////////
  28 class GFX_EXPORT InterpolatedTransform {
  29  public:
  30   InterpolatedTransform();
  31   // The interpolated transform varies only when t in (start_time, end_time).
  32   // If t <= start_time, Interpolate(t) will return the initial transform, and
  33   // if t >= end_time, Interpolate(t) will return the final transform.
  34   InterpolatedTransform(float start_time, float end_time);
  35   virtual ~InterpolatedTransform();
  36
  37   // Returns the interpolated transform at time t. Note: not virtual.
  38   gfx::Transform Interpolate(float t) const;
  39
  40   // The Intepolate ultimately returns the product of our transform at time t
  41   // and our child's transform at time t (if we have one).
  42   //
  43   // This function takes ownership of the passed InterpolatedTransform.
  44   void SetChild(InterpolatedTransform* child);
  45
  46   // If the interpolated transform is reversed, Interpolate(t) will return
  47   // Interpolate(1 - t)
  48   void SetReversed(bool reversed) { reversed_ = reversed; }
  49   bool Reversed() const { return reversed_; }
  50
  51  protected:
  52   // Calculates the interpolated transform without considering our child.
  53   virtual gfx::Transform InterpolateButDoNotCompose(float t) const = 0;
  54
  55   // If time in (start_time_, end_time_], this function linearly interpolates
  56   // between start_value and end_value.  More precisely it returns
  57   // (1 - t) * start_value + t * end_value where
  58   // t = (start_time_ - time) / (end_time_ - start_time_).
  59   // If time < start_time_ it returns start_value, and if time >= end_time_
  60   // it returns end_value.
  61   float ValueBetween(float time, float start_value, float end_value) const;
  62
  63   float start_time() const { return start_time_; }
  64   float end_time() const { return end_time_; }
  65
  66  private:
  67   const float start_time_;
  68   const float end_time_;
  69
  70   // The child transform. If you consider an interpolated transform as a
  71   // function of t. If, without a child, we are f(t), and our child is
  72   // g(t), then with a child we become f'(t) = f(t) * g(t). Using a child
  73   // transform, we can chain collections of transforms together.
  74   scoped_ptr<InterpolatedTransform> child_;
  75
  76   bool reversed_;
  77
  78   DISALLOW_COPY_AND_ASSIGN(InterpolatedTransform);
  79 };
  80
  81 ///////////////////////////////////////////////////////////////////////////////
  82 // class InterpolatedRotation
  83 //
  84 // Represents an animated rotation.
  85 //
  86 ///////////////////////////////////////////////////////////////////////////////
  87 class GFX_EXPORT InterpolatedRotation : public InterpolatedTransform {
  88  public:
  89   InterpolatedRotation(float start_degrees, float end_degrees);
  90   InterpolatedRotation(float start_degrees,
  91                        float end_degrees,
  92                        float start_time,
  93                        float end_time);
  94   virtual ~InterpolatedRotation();
  95
  96  protected:
  97   virtual gfx::Transform InterpolateButDoNotCompose(float t) const override;
  98
  99  private:
 100   const float start_degrees_;
 101   const float end_degrees_;
 102
 103   DISALLOW_COPY_AND_ASSIGN(InterpolatedRotation);
 104 };
 105
 106 ///////////////////////////////////////////////////////////////////////////////
 107 // class InterpolatedAxisAngleRotation
 108 //
 109 // Represents an animated rotation.
 110 //
 111 ///////////////////////////////////////////////////////////////////////////////
 112 class GFX_EXPORT InterpolatedAxisAngleRotation : public InterpolatedTransform {
 113  public:
 114   InterpolatedAxisAngleRotation(const gfx::Vector3dF& axis,
 115                                 float start_degrees,
 116                                 float end_degrees);
 117   InterpolatedAxisAngleRotation(const gfx::Vector3dF& axis,
 118                                 float start_degrees,
 119                                 float end_degrees,
 120                                 float start_time,
 121                                 float end_time);
 122   virtual ~InterpolatedAxisAngleRotation();
 123
 124  protected:
 125   virtual gfx::Transform InterpolateButDoNotCompose(float t) const override;
 126
 127  private:
 128   gfx::Vector3dF axis_;
 129   const float start_degrees_;
 130   const float end_degrees_;
 131
 132   DISALLOW_COPY_AND_ASSIGN(InterpolatedAxisAngleRotation);
 133 };
 134
 135 ///////////////////////////////////////////////////////////////////////////////
 136 // class InterpolatedScale
 137 //
 138 // Represents an animated scale.
 139 //
 140 ///////////////////////////////////////////////////////////////////////////////
 141 class GFX_EXPORT InterpolatedScale : public InterpolatedTransform {
 142  public:
 143   InterpolatedScale(float start_scale, float end_scale);
 144   InterpolatedScale(float start_scale, float end_scale,
 145                     float start_time, float end_time);
 146   InterpolatedScale(const gfx::Point3F& start_scale,
 147                     const gfx::Point3F& end_scale);
 148   InterpolatedScale(const gfx::Point3F& start_scale,
 149                     const gfx::Point3F& end_scale,
 150                     float start_time,
 151                     float end_time);
 152   virtual ~InterpolatedScale();
 153
 154  protected:
 155   virtual gfx::Transform InterpolateButDoNotCompose(float t) const override;
 156
 157  private:
 158   const gfx::Point3F start_scale_;
 159   const gfx::Point3F end_scale_;
 160
 161   DISALLOW_COPY_AND_ASSIGN(InterpolatedScale);
 162 };
 163
 164 class GFX_EXPORT InterpolatedTranslation : public InterpolatedTransform {
 165  public:
 166   InterpolatedTranslation(const gfx::Point& start_pos,
 167                           const gfx::Point& end_pos);
 168   InterpolatedTranslation(const gfx::Point& start_pos,
 169                           const gfx::Point& end_pos,
 170                           float start_time,
 171                           float end_time);
 172   InterpolatedTranslation(const gfx::Point3F& start_pos,
 173                           const gfx::Point3F& end_pos);
 174   InterpolatedTranslation(const gfx::Point3F& start_pos,
 175                           const gfx::Point3F& end_pos,
 176                           float start_time,
 177                           float end_time);
 178   virtual ~InterpolatedTranslation();
 179
 180  protected:
 181   virtual gfx::Transform InterpolateButDoNotCompose(float t) const override;
 182
 183  private:
 184   const gfx::Point3F start_pos_;
 185   const gfx::Point3F end_pos_;
 186
 187   DISALLOW_COPY_AND_ASSIGN(InterpolatedTranslation);
 188 };
 189
 190 ///////////////////////////////////////////////////////////////////////////////
 191 // class InterpolatedConstantTransform
 192 //
 193 // Represents a transform that is constant over time. This is only useful when
 194 // composed with other interpolated transforms.
 195 //
 196 // See InterpolatedTransformAboutPivot for an example of its usage.
 197 //
 198 ///////////////////////////////////////////////////////////////////////////////
 199 class GFX_EXPORT InterpolatedConstantTransform : public InterpolatedTransform {
 200  public:
 201   explicit InterpolatedConstantTransform(const gfx::Transform& transform);
 202   virtual ~InterpolatedConstantTransform();
 203
 204  protected:
 205   virtual gfx::Transform InterpolateButDoNotCompose(float t) const override;
 206
 207  private:
 208   const gfx::Transform transform_;
 209
 210   DISALLOW_COPY_AND_ASSIGN(InterpolatedConstantTransform);
 211 };
 212
 213 ///////////////////////////////////////////////////////////////////////////////
 214 // class InterpolatedTransformAboutPivot
 215 //
 216 // Represents an animated transform with a transformed origin. Essentially,
 217 // at each time, t, the interpolated transform is created by composing
 218 // P * T * P^-1 where P is a constant transform to the new origin.
 219 //
 220 ///////////////////////////////////////////////////////////////////////////////
 221 class GFX_EXPORT InterpolatedTransformAboutPivot
 222     : public InterpolatedTransform {
 223  public:
 224   // Takes ownership of the passed transform.
 225   InterpolatedTransformAboutPivot(const gfx::Point& pivot,
 226                                   InterpolatedTransform* transform);
 227
 228   // Takes ownership of the passed transform.
 229   InterpolatedTransformAboutPivot(const gfx::Point& pivot,
 230                                   InterpolatedTransform* transform,
 231                                   float start_time,
 232                                   float end_time);
 233   virtual ~InterpolatedTransformAboutPivot();
 234
 235  protected:
 236   virtual gfx::Transform InterpolateButDoNotCompose(float t) const override;
 237
 238  private:
 239   void Init(const gfx::Point& pivot, InterpolatedTransform* transform);
 240
 241   scoped_ptr<InterpolatedTransform> transform_;
 242
 243   DISALLOW_COPY_AND_ASSIGN(InterpolatedTransformAboutPivot);
 244 };
 245
 246 class GFX_EXPORT InterpolatedMatrixTransform : public InterpolatedTransform {
 247  public:
 248   InterpolatedMatrixTransform(const gfx::Transform& start_transform,
 249                               const gfx::Transform& end_transform);
 250
 251   InterpolatedMatrixTransform(const gfx::Transform& start_transform,
 252                               const gfx::Transform& end_transform,
 253                               float start_time,
 254                               float end_time);
 255
 256   virtual ~InterpolatedMatrixTransform();
 257
 258  protected:
 259   virtual gfx::Transform InterpolateButDoNotCompose(float t) const override;
 260
 261  private:
 262   void Init(const gfx::Transform& start_transform,
 263             const gfx::Transform& end_transform);
 264
 265   gfx::DecomposedTransform start_decomp_;
 266   gfx::DecomposedTransform end_decomp_;
 267 };
 268
 269 } // namespace ui
 270
 271 #endif  // UI_GFX_INTERPOLATED_TRANSFORM_H_