Do something more interesting than printf when an event is received by sample_app.

R=abarth@chromium.org
http://crbug.com/324639

Review URL: https://codereview.chromium.org/108273008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239910 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 127 insertions, 22 deletions

diff --git a/mojo/examples/sample_app/DEPS b/mojo/examples/sample_app/DEPS
new file mode 100644
index 0000000..49b9c28
--- /dev/null
+++ b/mojo/examples/sample_app/DEPS
@@ -0,0 +1,4 @@
+include_rules = [
+  "+ui/events/event_constants.h",  # pending enum support in mojom
+  "+ui/gfx",  # TODO(beng): trim the size of this dep.
+]
diff --git a/mojo/examples/sample_app/gles2_client_impl.cc b/mojo/examples/sample_app/gles2_client_impl.cc
index 2a87ca0..ea89cb7 100644
--- a/mojo/examples/sample_app/gles2_client_impl.cc
+++ b/mojo/examples/sample_app/gles2_client_impl.cc
@@ -8,9 +8,17 @@
 #include <GLES2/gl2ext.h>
 
 #include "mojo/public/gles2/gles2.h"
+#include "ui/events/event_constants.h"
 
 namespace mojo {
 namespace examples {
+namespace {
+
+float CalculateDragDistance(const gfx::PointF& start, const Point& end) {
+  return hypot(start.x() - end.x(), start.y() - end.y());
+}
+
+}
 
 GLES2ClientImpl::GLES2ClientImpl(ScopedMessagePipeHandle pipe)
     : service_(pipe.Pass()) {
@@ -21,29 +29,71 @@ GLES2ClientImpl::~GLES2ClientImpl() {
   service_->Destroy();
 }
 
+void GLES2ClientImpl::HandleInputEvent(const Event& event) {
+  switch (event.action()) {
+  case ui::ET_MOUSE_PRESSED:
+  case ui::ET_TOUCH_PRESSED:
+    timer_.Stop();
+    capture_point_.SetPoint(event.location().x(), event.location().y());
+    last_drag_point_ = capture_point_;
+    drag_start_time_ = base::Time::Now();
+    break;
+  case ui::ET_MOUSE_DRAGGED:
+  case ui::ET_TOUCH_MOVED:
+    if (!timer_.IsRunning()) {
+      int direction = event.location().y() < last_drag_point_.y() ||
+          event.location().x() > last_drag_point_.x() ? 1 : -1;
+      cube_.set_direction(direction);
+      cube_.UpdateForDragDistance(
+          CalculateDragDistance(last_drag_point_, event.location()));
+      cube_.Draw();
+      MojoGLES2SwapBuffers();
+
+      last_drag_point_.SetPoint(event.location().x(), event.location().y());
+    }
+    break;
+  case ui::ET_MOUSE_RELEASED:
+  case ui::ET_TOUCH_RELEASED: {
+      cube_.SetFlingMultiplier(
+          CalculateDragDistance(capture_point_, event.location()),
+          base::TimeDelta(base::Time::Now() - drag_start_time_).InSecondsF());
+
+      capture_point_ = last_drag_point_ = gfx::PointF();
+      StartTimer();
+    }
+    break;
+  default:
+    break;
+  }
+}
+
 void GLES2ClientImpl::DidCreateContext(uint64_t encoded,
                                        uint32_t width,
                                        uint32_t height) {
   MojoGLES2MakeCurrent(encoded);
 
   cube_.Init(width, height);
-  last_time_ = base::Time::Now();
-  timer_.Start(FROM_HERE, base::TimeDelta::FromMilliseconds(16),
-               this, &GLES2ClientImpl::Draw);
+  StartTimer();
+}
+
+void GLES2ClientImpl::ContextLost() {
+  timer_.Stop();
 }
 
 void GLES2ClientImpl::Draw() {
   base::Time now = base::Time::Now();
   base::TimeDelta offset = now - last_time_;
   last_time_ = now;
-  cube_.Update(offset.InSecondsF());
+  cube_.UpdateForTimeDelta(offset.InSecondsF());
   cube_.Draw();
 
   MojoGLES2SwapBuffers();
 }
 
-void GLES2ClientImpl::ContextLost() {
-  timer_.Stop();
+void GLES2ClientImpl::StartTimer() {
+  last_time_ = base::Time::Now();
+  timer_.Start(FROM_HERE, base::TimeDelta::FromMilliseconds(16),
+               this, &GLES2ClientImpl::Draw);
 }
 
 }  // namespace examples
diff --git a/mojo/examples/sample_app/gles2_client_impl.h b/mojo/examples/sample_app/gles2_client_impl.h
index 1d38a3c..300557a 100644
--- a/mojo/examples/sample_app/gles2_client_impl.h
+++ b/mojo/examples/sample_app/gles2_client_impl.h
@@ -5,10 +5,13 @@
 #ifndef MOJO_EXAMPLES_SAMPLE_APP_GLES2_CLIENT_IMPL_H_
 #define MOJO_EXAMPLES_SAMPLE_APP_GLES2_CLIENT_IMPL_H_
 
+#include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "mojo/examples/sample_app/spinning_cube.h"
 #include "mojo/public/bindings/lib/remote_ptr.h"
 #include "mojom/gles2.h"
+#include "mojom/native_viewport.h"
+#include "ui/gfx/point_f.h"
 
 namespace mojo {
 namespace examples {
@@ -18,6 +21,8 @@ class GLES2ClientImpl : public GLES2ClientStub {
   explicit GLES2ClientImpl(ScopedMessagePipeHandle pipe);
   virtual ~GLES2ClientImpl();
 
+  void HandleInputEvent(const Event& event);
+
  private:
   virtual void DidCreateContext(uint64_t encoded,
                                 uint32_t width,
@@ -25,10 +30,14 @@ class GLES2ClientImpl : public GLES2ClientStub {
   virtual void ContextLost() MOJO_OVERRIDE;
 
   void Draw();
+  void StartTimer();
 
   base::Time last_time_;
   base::RepeatingTimer<GLES2ClientImpl> timer_;
   SpinningCube cube_;
+  gfx::PointF capture_point_;
+  gfx::PointF last_drag_point_;
+  base::Time drag_start_time_;
 
   RemotePtr<GLES2> service_;
 
diff --git a/mojo/examples/sample_app/native_viewport_client_impl.cc b/mojo/examples/sample_app/native_viewport_client_impl.cc
index 2fc2d98..17991da 100644
--- a/mojo/examples/sample_app/native_viewport_client_impl.cc
+++ b/mojo/examples/sample_app/native_viewport_client_impl.cc
@@ -41,8 +41,8 @@ void NativeViewportClientImpl::OnDestroyed() {
 
 void NativeViewportClientImpl::OnEvent(const Event& event) {
   if (!event.location().is_null()) {
-    LOG(INFO) << "Located Event @"
-              << event.location().x() << "," << event.location().y();
+    gles2_client_->HandleInputEvent(event);
+    service_->AckEvent(event);
   }
 }
 
diff --git a/mojo/examples/sample_app/spinning_cube.cc b/mojo/examples/sample_app/spinning_cube.cc
index 3a09132..7983563 100644
--- a/mojo/examples/sample_app/spinning_cube.cc
+++ b/mojo/examples/sample_app/spinning_cube.cc
@@ -293,8 +293,16 @@ class ESMatrix {
   }
 };
 
+float RotationForTimeDelta(float delta_time) {
+  return delta_time * 40.0f;
 }
 
+float RotationForDragDistance(float drag_distance) {
+  return drag_distance / 5; // Arbitrary damping.
+}
+
+}  // namespace
+
 class SpinningCube::GLState {
  public:
   GLState();
@@ -330,7 +338,9 @@ SpinningCube::SpinningCube()
     : initialized_(false),
       width_(0),
       height_(0),
-      state_(new GLState()) {
+      state_(new GLState()),
+      fling_multiplier_(1.0f),
+      direction_(1) {
   state_->angle_ = 45.0f;
 }
 
@@ -384,23 +394,33 @@ void SpinningCube::OnGLContextLost() {
   state_->OnGLContextLost();
 }
 
-void SpinningCube::Update(float delta_time) {
-  state_->angle_ += ( delta_time * 40.0f );
-  if (state_->angle_ >= 360.0f )
+void SpinningCube::SetFlingMultiplier(float drag_distance,
+                                      float drag_time) {
+  fling_multiplier_ = RotationForDragDistance(drag_distance) /
+      RotationForTimeDelta(drag_time);
+
+}
+
+void SpinningCube::UpdateForTimeDelta(float delta_time) {
+  state_->angle_ += RotationForTimeDelta(delta_time) * fling_multiplier_;
+  if (state_->angle_ >= 360.0f)
     state_->angle_ -= 360.0f;
 
-  float aspect = static_cast<GLfloat>(width_) / static_cast<GLfloat>(height_);
+  // Arbitrary 50-step linear reduction in spin speed.
+  if (fling_multiplier_ > 1.0f) {
+    fling_multiplier_ =
+        std::max(1.0f, fling_multiplier_ - (fling_multiplier_ - 1.0f) / 50);
+  }
 
-  ESMatrix perspective;
-  perspective.LoadIdentity();
-  perspective.Perspective(60.0f, aspect, 1.0f, 20.0f );
+  Update();
+}
 
-  ESMatrix modelview;
-  modelview.LoadIdentity();
-  modelview.Translate(0.0, 0.0, -2.0);
-  modelview.Rotate(state_->angle_, 1.0, 0.0, 1.0);
+void SpinningCube::UpdateForDragDistance(float distance) {
+  state_->angle_ += RotationForDragDistance(distance);
+  if (state_->angle_ >= 360.0f )
+    state_->angle_ -= 360.0f;
 
-  state_->mvp_matrix_.Multiply(&modelview, &perspective);
+  Update();
 }
 
 void SpinningCube::Draw() {
@@ -425,5 +445,20 @@ void SpinningCube::Draw() {
                     0);
 }
 
+void SpinningCube::Update() {
+  float aspect = static_cast<GLfloat>(width_) / static_cast<GLfloat>(height_);
+
+  ESMatrix perspective;
+  perspective.LoadIdentity();
+  perspective.Perspective(60.0f, aspect, 1.0f, 20.0f );
+
+  ESMatrix modelview;
+  modelview.LoadIdentity();
+  modelview.Translate(0.0, 0.0, -2.0);
+  modelview.Rotate(state_->angle_ * direction_, 1.0, 0.0, 1.0);
+
+  state_->mvp_matrix_.Multiply(&modelview, &perspective);
+}
+
 }  // namespace examples
 }  // namespace mojo
diff --git a/mojo/examples/sample_app/spinning_cube.h b/mojo/examples/sample_app/spinning_cube.h
index c4a81ea..9cd78b8 100644
--- a/mojo/examples/sample_app/spinning_cube.h
+++ b/mojo/examples/sample_app/spinning_cube.h
@@ -18,7 +18,10 @@ class SpinningCube {
   ~SpinningCube();
 
   void Init(uint32_t width, uint32_t height);
-  void Update(float delta_time);
+  void set_direction(int direction) { direction_ = direction; }
+  void SetFlingMultiplier(float drag_distance, float drag_time);
+  void UpdateForTimeDelta(float delta_time);
+  void UpdateForDragDistance(float distance);
   void Draw();
 
   void OnGLContextLost();
@@ -26,10 +29,14 @@ class SpinningCube {
  private:
   class GLState;
 
+  void Update();
+
   bool initialized_;
   uint32_t width_;
   uint32_t height_;
   scoped_ptr<GLState> state_;
+  float fling_multiplier_;
+  int direction_;
 };
 
 }  // namespace examples