| // Copyright 2018 The Fuchsia Authors. All rights reserved. | |
| // Use of this source code is governed by a BSD-style license that can be | |
| // found in the LICENSE file. | |
| #pragma once | |
| #include <inttypes.h> | |
| static inline uint32_t interpolate(uint32_t max, int32_t cur_frame, int32_t period) { | |
| float fraction = ((float) (cur_frame % period)) / ((float) period - 1); | |
| fraction = (cur_frame / period) % 2 ? 1.0f - fraction : fraction; | |
| return (uint32_t) ((float) max * fraction); | |
| } | |