| // Copyright 2017 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "ui/events/gestures/fixed_velocity_curve.h" |
| |
| namespace ui { |
| |
| FixedVelocityCurve::FixedVelocityCurve(const gfx::Vector2dF& velocity, |
| base::TimeTicks start_timestamp) |
| : velocity_(velocity), start_timestamp_(start_timestamp) {} |
| |
| FixedVelocityCurve::~FixedVelocityCurve() {} |
| |
| // GestureCurve implementation. |
| bool FixedVelocityCurve::ComputeScrollOffset(base::TimeTicks time, |
| gfx::Vector2dF* offset, |
| gfx::Vector2dF* velocity) { |
| *velocity = velocity_; |
| |
| const float kConstantMultiplier = 5000.0f; |
| float multiplier = |
| (time - start_timestamp_).InSecondsF() * kConstantMultiplier; |
| *offset = gfx::ScaleVector2d(velocity_, multiplier); |
| return true; |
| } |
| |
| } // namespace ui |