content/browser/android/edge_effect_base.cc

   1 // Copyright 2015 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 #include "content/browser/android/edge_effect_base.h"
   6
   7 namespace content {
   8
   9 // static
  10 gfx::Transform EdgeEffectBase::ComputeTransform(Edge edge,
  11                                                 const gfx::SizeF& viewport_size,
  12                                                 float offset) {
  13   // Transforms assume the edge layers are anchored to their *top center point*.
  14   switch (edge) {
  15     case EDGE_TOP:
  16       return gfx::Transform(1, 0, 0, 1, 0, offset);
  17     case EDGE_LEFT:
  18       return gfx::Transform(0, 1, -1, 0, -viewport_size.height() / 2.f + offset,
  19                             viewport_size.height() / 2.f);
  20     case EDGE_BOTTOM:
  21       return gfx::Transform(-1, 0, 0, -1, 0, viewport_size.height() + offset);
  22     case EDGE_RIGHT:
  23       return gfx::Transform(0, -1, 1, 0, -viewport_size.height() / 2.f +
  24                                              viewport_size.width() + offset,
  25                             viewport_size.height() / 2.f);
  26     default:
  27       NOTREACHED() << "Invalid edge: " << edge;
  28       return gfx::Transform();
  29   };
  30 }
  31
  32 // static
  33 gfx::SizeF EdgeEffectBase::ComputeOrientedSize(
  34     Edge edge,
  35     const gfx::SizeF& viewport_size) {
  36   switch (edge) {
  37     case EDGE_TOP:
  38     case EDGE_BOTTOM:
  39       return viewport_size;
  40     case EDGE_LEFT:
  41     case EDGE_RIGHT:
  42       return gfx::SizeF(viewport_size.height(), viewport_size.width());
  43     default:
  44       NOTREACHED() << "Invalid edge: " << edge;
  45       return gfx::SizeF();
  46   };
  47 }
  48
  49 }  // namespace content