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#include "ash/touch/touch_hud_projection.h"
6
7#include "ash/root_window_controller.h"
8#include "ash/shell.h"
9#include "third_party/skia/include/effects/SkGradientShader.h"
10#include "ui/events/event.h"
11#include "ui/gfx/animation/animation_delegate.h"
12#include "ui/gfx/animation/linear_animation.h"
13#include "ui/gfx/canvas.h"
14#include "ui/gfx/size.h"
15#include "ui/views/widget/widget.h"
16
17namespace ash {
18
19const int kPointRadius = 20;
20const SkColor kProjectionFillColor = SkColorSetRGB(0xF5, 0xF5, 0xDC);
21const SkColor kProjectionStrokeColor = SK_ColorGRAY;
22const int kProjectionAlpha = 0xB0;
23const int kFadeoutDurationInMs = 250;
24const int kFadeoutFrameRate = 60;
25
26// TouchPointView draws a single touch point. This object manages its own
27// lifetime and deletes itself upon fade-out completion or whenever |Remove()|
28// is explicitly called.
29class TouchPointView : public views::View,
30                       public gfx::AnimationDelegate,
31                       public views::WidgetObserver {
32 public:
33  explicit TouchPointView(views::Widget* parent_widget)
34      : circle_center_(kPointRadius + 1, kPointRadius + 1),
35        gradient_center_(SkPoint::Make(kPointRadius + 1,
36                                       kPointRadius + 1)) {
37    SetPaintToLayer(true);
38    SetFillsBoundsOpaquely(false);
39
40    SetSize(gfx::Size(2 * kPointRadius + 2, 2 * kPointRadius + 2));
41
42    stroke_paint_.setStyle(SkPaint::kStroke_Style);
43    stroke_paint_.setColor(kProjectionStrokeColor);
44
45    gradient_colors_[0] = kProjectionFillColor;
46    gradient_colors_[1] = kProjectionStrokeColor;
47
48    gradient_pos_[0] = SkFloatToScalar(0.9f);
49    gradient_pos_[1] = SkFloatToScalar(1.0f);
50
51    parent_widget->GetContentsView()->AddChildView(this);
52
53    parent_widget->AddObserver(this);
54  }
55
56  void UpdateTouch(const ui::TouchEvent& touch) {
57    if (touch.type() == ui::ET_TOUCH_RELEASED ||
58        touch.type() == ui::ET_TOUCH_CANCELLED) {
59      fadeout_.reset(new gfx::LinearAnimation(kFadeoutDurationInMs,
60                                             kFadeoutFrameRate,
61                                             this));
62      fadeout_->Start();
63    } else {
64      SetX(parent()->GetMirroredXInView(touch.root_location().x()) -
65               kPointRadius - 1);
66      SetY(touch.root_location().y() - kPointRadius - 1);
67    }
68  }
69
70  void Remove() {
71    delete this;
72  }
73
74 private:
75  virtual ~TouchPointView() {
76    GetWidget()->RemoveObserver(this);
77    parent()->RemoveChildView(this);
78  }
79
80  // Overridden from views::View.
81  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE {
82    int alpha = kProjectionAlpha;
83    if (fadeout_)
84      alpha = static_cast<int>(fadeout_->CurrentValueBetween(alpha, 0));
85    fill_paint_.setAlpha(alpha);
86    stroke_paint_.setAlpha(alpha);
87    SkShader* shader = SkGradientShader::CreateRadial(
88        gradient_center_,
89        SkIntToScalar(kPointRadius),
90        gradient_colors_,
91        gradient_pos_,
92        arraysize(gradient_colors_),
93        SkShader::kMirror_TileMode);
94    fill_paint_.setShader(shader);
95    shader->unref();
96    canvas->DrawCircle(circle_center_, SkIntToScalar(kPointRadius),
97                       fill_paint_);
98    canvas->DrawCircle(circle_center_, SkIntToScalar(kPointRadius),
99                       stroke_paint_);
100  }
101
102  // Overridden from gfx::AnimationDelegate.
103  virtual void AnimationEnded(const gfx::Animation* animation) OVERRIDE {
104    DCHECK_EQ(fadeout_.get(), animation);
105    delete this;
106  }
107
108  virtual void AnimationProgressed(const gfx::Animation* animation) OVERRIDE {
109    DCHECK_EQ(fadeout_.get(), animation);
110    SchedulePaint();
111  }
112
113  virtual void AnimationCanceled(const gfx::Animation* animation) OVERRIDE {
114    AnimationEnded(animation);
115  }
116
117  // Overridden from views::WidgetObserver.
118  virtual void OnWidgetDestroying(views::Widget* widget) OVERRIDE {
119    if (fadeout_)
120      fadeout_->Stop();
121    else
122      Remove();
123  }
124
125  const gfx::Point circle_center_;
126  const SkPoint gradient_center_;
127
128  SkPaint fill_paint_;
129  SkPaint stroke_paint_;
130  SkColor gradient_colors_[2];
131  SkScalar gradient_pos_[2];
132
133  scoped_ptr<gfx::Animation> fadeout_;
134
135  DISALLOW_COPY_AND_ASSIGN(TouchPointView);
136};
137
138TouchHudProjection::TouchHudProjection(aura::Window* initial_root)
139    : TouchObserverHUD(initial_root) {
140}
141
142TouchHudProjection::~TouchHudProjection() {
143}
144
145void TouchHudProjection::Clear() {
146  for (std::map<int, TouchPointView*>::iterator iter = points_.begin();
147      iter != points_.end(); iter++)
148    iter->second->Remove();
149  points_.clear();
150}
151
152void TouchHudProjection::OnTouchEvent(ui::TouchEvent* event) {
153  if (event->type() == ui::ET_TOUCH_PRESSED) {
154    TouchPointView* point = new TouchPointView(widget());
155    point->UpdateTouch(*event);
156    std::pair<std::map<int, TouchPointView*>::iterator, bool> result =
157        points_.insert(std::make_pair(event->touch_id(), point));
158    // If a |TouchPointView| is already mapped to the touch id, remove it and
159    // replace it with the new one.
160    if (!result.second) {
161      result.first->second->Remove();
162      result.first->second = point;
163    }
164  } else {
165    std::map<int, TouchPointView*>::iterator iter =
166        points_.find(event->touch_id());
167    if (iter != points_.end()) {
168      iter->second->UpdateTouch(*event);
169      if (event->type() == ui::ET_TOUCH_RELEASED ||
170          event->type() == ui::ET_TOUCH_CANCELLED)
171        points_.erase(iter);
172    }
173  }
174}
175
176void TouchHudProjection::SetHudForRootWindowController(
177    RootWindowController* controller) {
178  controller->set_touch_hud_projection(this);
179}
180
181void TouchHudProjection::UnsetHudForRootWindowController(
182    RootWindowController* controller) {
183  controller->set_touch_hud_projection(NULL);
184}
185
186}  // namespace ash
187