| Index: webkit/child/touch_fling_gesture_curve.cc
|
| diff --git a/webkit/child/touch_fling_gesture_curve.cc b/webkit/child/touch_fling_gesture_curve.cc
|
| deleted file mode 100644
|
| index 274dcaa355b1a53e173a14766db48e2096cffdfd..0000000000000000000000000000000000000000
|
| --- a/webkit/child/touch_fling_gesture_curve.cc
|
| +++ /dev/null
|
| @@ -1,163 +0,0 @@
|
| -// 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/touch_fling_gesture_curve.h"
|
| -
|
| -#include <cmath>
|
| -
|
| -#include "base/debug/trace_event.h"
|
| -#include "base/logging.h"
|
| -#include "third_party/WebKit/public/platform/WebFloatPoint.h"
|
| -#include "third_party/WebKit/public/platform/WebFloatSize.h"
|
| -#include "third_party/WebKit/public/platform/WebGestureCurve.h"
|
| -#include "third_party/WebKit/public/platform/WebGestureCurveTarget.h"
|
| -#include "third_party/WebKit/public/platform/WebSize.h"
|
| -
|
| -using WebKit::WebFloatPoint;
|
| -using WebKit::WebFloatSize;
|
| -using WebKit::WebGestureCurve;
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| -using WebKit::WebGestureCurveTarget;
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| -using WebKit::WebSize;
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| -
|
| -namespace {
|
| -
|
| -const char* kCurveName = "TouchFlingGestureCurve";
|
| -
|
| -inline double position(double t, float* p) {
|
| - return p[0] * exp(-p[2] * t) - p[1] * t - p[0];
|
| -}
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| -
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| -inline double velocity(double t, float* p) {
|
| - return -p[0] * p[2] * exp(-p[2] * t) - p[1];
|
| -}
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| -
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| -inline double timeAtVelocity(double v, float* p) {
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| - DCHECK(p[0]);
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| - DCHECK(p[2]);
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| - return -log((v + p[1]) / (-p[0] * p[2])) / p[2];
|
| -}
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| -
|
| -} // namespace
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| -
|
| -
|
| -namespace webkit_glue {
|
| -
|
| -// This curve implementation is based on the notion of a single, absolute
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| -// curve, which starts at a large velocity and smoothly decreases to
|
| -// zero. For a given input velocity, we find where on the curve this
|
| -// velocity occurs, and start the animation at this point---denoted by
|
| -// (time_offset_, position_offset_).
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| -//
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| -// This has the effect of automatically determining an animation duration
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| -// that scales with input velocity, as faster initial velocities start
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| -// earlier on the curve and thus take longer to reach the end. No
|
| -// complicated time scaling is required.
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| -//
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| -// Since the starting velocity is implicitly determined by our starting
|
| -// point, we only store the relative magnitude and direction of both
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| -// initial x- and y-velocities, and use this to scale the computed
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| -// displacement at any point in time. This guarantees that fling
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| -// trajectories are straight lines when viewed in x-y space. Initial
|
| -// velocities that lie outside the max velocity are constrained to start
|
| -// at zero (and thus are implicitly scaled).
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| -//
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| -// The curve is modelled as a 4th order polynomial, starting at t = 0,
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| -// and ending at t = curve_duration_. Attempts to generate
|
| -// position/velocity estimates outside this range are undefined.
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| -
|
| -WebGestureCurve* TouchFlingGestureCurve::Create(
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| - const WebFloatPoint& initial_velocity,
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| - float p0,
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| - float p1,
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| - float p2,
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| - const WebSize& cumulative_scroll) {
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| - return new TouchFlingGestureCurve(initial_velocity, p0, p1, p2,
|
| - cumulative_scroll);
|
| -}
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| -
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| -TouchFlingGestureCurve::TouchFlingGestureCurve(
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| - const WebFloatPoint& initial_velocity,
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| - float alpha,
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| - float beta,
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| - float gamma,
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| - const WebSize& cumulative_scroll)
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| - : cumulative_scroll_(WebFloatSize(cumulative_scroll.width,
|
| - cumulative_scroll.height)) {
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| - DCHECK(initial_velocity != WebFloatPoint());
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| -
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| - coefficients_[0] = alpha;
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| - coefficients_[1] = beta;
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| - coefficients_[2] = gamma;
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| -
|
| - // Curve ends when velocity reaches zero.
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| - curve_duration_ = timeAtVelocity(0, coefficients_);
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| - DCHECK(curve_duration_ > 0);
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| -
|
| - float max_start_velocity = std::max(fabs(initial_velocity.x),
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| - fabs(initial_velocity.y));
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| -
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| - // Force max_start_velocity to lie in the range v(0) to v(curve_duration),
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| - // and assume that the curve parameters define a monotonically decreasing
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| - // velocity, or else bisection search may fail.
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| - if (max_start_velocity > velocity(0, coefficients_))
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| - max_start_velocity = velocity(0, coefficients_);
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| -
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| - if (max_start_velocity < 0)
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| - max_start_velocity = 0;
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| -
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| - // We keep track of relative magnitudes and directions of the
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| - // velocity/displacement components here.
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| - displacement_ratio_ = WebFloatPoint(initial_velocity.x / max_start_velocity,
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| - initial_velocity.y / max_start_velocity);
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| -
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| - // Compute time-offset for start velocity.
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| - time_offset_ = timeAtVelocity(max_start_velocity, coefficients_);
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| -
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| - // Compute curve position at offset time
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| - position_offset_ = position(time_offset_, coefficients_);
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| - TRACE_EVENT_ASYNC_BEGIN1("input", "GestureAnimation", this, "curve",
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| - kCurveName);
|
| -}
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| -
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| -TouchFlingGestureCurve::~TouchFlingGestureCurve() {
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| - TRACE_EVENT_ASYNC_END0("input", "GestureAnimation", this);
|
| -}
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| -
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| -bool TouchFlingGestureCurve::apply(double time, WebGestureCurveTarget* target) {
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| - float displacement;
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| - float speed;
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| - if (time < 0) {
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| - displacement = 0.f;
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| - speed = 0.f;
|
| - } else if (time + time_offset_ < curve_duration_) {
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| - displacement =
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| - position(time + time_offset_, coefficients_) - position_offset_;
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| - speed = velocity(time + time_offset_, coefficients_);
|
| - } else {
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| - displacement = position(curve_duration_, coefficients_) - position_offset_;
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| - speed = 0.f;
|
| - }
|
| -
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| - // Keep track of integer portion of scroll thus far, and prepare increment.
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| - WebFloatSize scroll(displacement * displacement_ratio_.x,
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| - displacement * displacement_ratio_.y);
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| - WebFloatSize scroll_increment(scroll.width - cumulative_scroll_.width,
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| - scroll.height - cumulative_scroll_.height);
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| - WebFloatSize scroll_velocity(speed * displacement_ratio_.x,
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| - speed * displacement_ratio_.y);
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| - cumulative_scroll_ = scroll;
|
| -
|
| - if (time + time_offset_ < curve_duration_ ||
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| - scroll_increment != WebFloatSize()) {
|
| - target->notifyCurrentFlingVelocity(scroll_velocity);
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| - // scrollBy() could delete this curve if the animation is over, so don't
|
| - // touch any member variables after making that call.
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| - target->scrollBy(scroll_increment);
|
| - return true;
|
| - }
|
| -
|
| - return false;
|
| -}
|
| -
|
| -} // namespace webkit_glue
|
|
|