| // Copyright (c) 2012 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. |
| |
| #include "webkit/child/fling_animator_impl_android.h" |
| |
| #include "base/android/jni_android.h" |
| #include "base/android/scoped_java_ref.h" |
| #include "base/logging.h" |
| #include "jni/OverScroller_jni.h" |
| #include "third_party/WebKit/public/platform/WebFloatSize.h" |
| #include "third_party/WebKit/public/platform/WebGestureCurveTarget.h" |
| #include "ui/gfx/screen.h" |
| #include "ui/gfx/vector2d.h" |
| |
| namespace webkit_glue { |
| |
| namespace { |
| static const float kEpsilon = 1e-4; |
| } |
| |
| FlingAnimatorImpl::FlingAnimatorImpl() |
| : is_active_(false) { |
| // hold the global reference of the Java objects. |
| JNIEnv* env = base::android::AttachCurrentThread(); |
| java_scroller_.Reset(JNI_OverScroller::Java_OverScroller_ConstructorAWOS_ACC( |
| env, |
| base::android::GetApplicationContext())); |
| } |
| |
| FlingAnimatorImpl::~FlingAnimatorImpl() |
| { |
| } |
| |
| //static |
| bool FlingAnimatorImpl::RegisterJni(JNIEnv* env) { |
| return JNI_OverScroller::RegisterNativesImpl(env); |
| } |
| |
| void FlingAnimatorImpl::StartFling(const gfx::PointF& velocity) |
| { |
| // No bounds on the fling. See http://webkit.org/b/96403 |
| // Instead, use the largest possible bounds for minX/maxX/minY/maxY. The |
| // compositor will ignore any attempt to scroll beyond the end of the page. |
| |
| DCHECK(velocity.x() || velocity.y()); |
| if (is_active_) |
| CancelFling(); |
| |
| is_active_ = true; |
| last_time_ = 0; |
| last_velocity_ = velocity; |
| |
| JNIEnv* env = base::android::AttachCurrentThread(); |
| |
| JNI_OverScroller::Java_OverScroller_flingV_I_I_I_I_I_I_I_I( |
| env, java_scroller_.obj(), 0, 0, |
| static_cast<int>(velocity.x()), |
| static_cast<int>(velocity.y()), |
| INT_MIN, INT_MAX, INT_MIN, INT_MAX); |
| } |
| |
| void FlingAnimatorImpl::CancelFling() |
| { |
| if (!is_active_) |
| return; |
| |
| is_active_ = false; |
| JNIEnv* env = base::android::AttachCurrentThread(); |
| JNI_OverScroller::Java_OverScroller_abortAnimation(env, java_scroller_.obj()); |
| } |
| |
| bool FlingAnimatorImpl::UpdatePosition() |
| { |
| JNIEnv* env = base::android::AttachCurrentThread(); |
| bool result = JNI_OverScroller::Java_OverScroller_computeScrollOffset( |
| env, |
| java_scroller_.obj()); |
| return is_active_ = result; |
| } |
| |
| gfx::Point FlingAnimatorImpl::GetCurrentPosition() |
| { |
| JNIEnv* env = base::android::AttachCurrentThread(); |
| gfx::Point position( |
| JNI_OverScroller::Java_OverScroller_getCurrX(env, java_scroller_.obj()), |
| JNI_OverScroller::Java_OverScroller_getCurrY(env, java_scroller_.obj())); |
| return position; |
| } |
| |
| float FlingAnimatorImpl::GetCurrentVelocity() |
| { |
| JNIEnv* env = base::android::AttachCurrentThread(); |
| // TODO(jdduke): Add Java-side hooks for getCurrVelocityX/Y, and return |
| // vector velocity. |
| return JNI_OverScroller::Java_OverScroller_getCurrVelocity( |
| env, java_scroller_.obj()); |
| } |
| |
| bool FlingAnimatorImpl::apply(double time, |
| blink::WebGestureCurveTarget* target) { |
| if (!UpdatePosition()) |
| return false; |
| |
| gfx::Point current_position = GetCurrentPosition(); |
| gfx::Vector2d diff(current_position - last_position_); |
| last_position_ = current_position; |
| float dpi_scale = gfx::Screen::GetNativeScreen()->GetPrimaryDisplay() |
| .device_scale_factor(); |
| blink::WebFloatSize scroll_amount(diff.x() / dpi_scale, |
| diff.y() / dpi_scale); |
| |
| float delta_time = time - last_time_; |
| last_time_ = time; |
| |
| // Currently, the OverScroller only provides the velocity magnitude; use the |
| // angle of the scroll delta to yield approximate x and y velocity components. |
| // TODO(jdduke): Remove this when we can properly poll OverScroller velocity. |
| gfx::PointF current_velocity = last_velocity_; |
| if (delta_time > kEpsilon) { |
| float diff_length = diff.Length(); |
| if (diff_length > kEpsilon) { |
| float velocity = GetCurrentVelocity(); |
| float scroll_to_velocity = velocity / diff_length; |
| current_velocity = gfx::PointF(diff.x() * scroll_to_velocity, |
| diff.y() * scroll_to_velocity); |
| } |
| } |
| last_velocity_ = current_velocity; |
| blink::WebFloatSize fling_velocity(current_velocity.x() / dpi_scale, |
| current_velocity.y() / dpi_scale); |
| target->notifyCurrentFlingVelocity(fling_velocity); |
| |
| // scrollBy() could delete this curve if the animation is over, so don't touch |
| // any member variables after making that call. |
| target->scrollBy(scroll_amount); |
| return true; |
| } |
| |
| FlingAnimatorImpl* FlingAnimatorImpl::CreateAndroidGestureCurve( |
| const blink::WebFloatPoint& velocity, |
| const blink::WebSize&) { |
| FlingAnimatorImpl* gesture_curve = new FlingAnimatorImpl(); |
| gesture_curve->StartFling(velocity); |
| return gesture_curve; |
| } |
| |
| } // namespace webkit_glue |