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// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "ash/accessibility/switch_access/point_scan_layer_animation_info.h"
namespace {
constexpr base::TimeDelta kLingerDelay = base::Milliseconds(250);
}
namespace ash {
void PointScanLayerAnimationInfo::Clear() {
start_time = base::TimeTicks();
change_time = base::TimeTicks();
linger_until = base::TimeTicks();
offset = 0;
offset_bound = 0;
offset_start = 0;
}
void ComputeOffset(PointScanLayerAnimationInfo* animation_info,
base::TimeTicks timestamp) {
if (timestamp < animation_info->start_time)
timestamp = animation_info->start_time;
if (timestamp < animation_info->linger_until)
return;
base::TimeTicks change_from_time =
std::max(animation_info->linger_until, animation_info->start_time);
float change_delta = (timestamp - change_from_time).InSecondsF();
if (change_from_time == base::TimeTicks())
change_delta = 0;
float offset_delta = animation_info->offset_bound *
(change_delta / animation_info->animation_rate);
animation_info->offset += offset_delta;
if (animation_info->offset > animation_info->offset_bound) {
animation_info->offset = animation_info->offset_bound;
animation_info->animation_rate *= -1;
animation_info->linger_until = timestamp + kLingerDelay;
} else if (animation_info->offset < animation_info->offset_start) {
animation_info->offset = animation_info->offset_start;
animation_info->animation_rate *= -1;
animation_info->linger_until = timestamp + kLingerDelay;
}
}
} // namespace ash
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