mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-12-27 12:18:55 +01:00
69 lines
2.1 KiB
C++
Vendored
69 lines
2.1 KiB
C++
Vendored
/*
|
|
* Copyright 2015 The Android Open Source Project
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#include <algorithm>
|
|
#include <cassert>
|
|
#include <stdint.h>
|
|
|
|
#include "oboe_fifo_FifoControllerBase_android.h"
|
|
|
|
namespace oboe {
|
|
|
|
FifoControllerBase::FifoControllerBase(uint32_t capacityInFrames)
|
|
: mTotalFrames(capacityInFrames)
|
|
{
|
|
// Avoid ridiculously large buffers and the arithmetic wraparound issues that can follow.
|
|
assert(capacityInFrames <= (UINT32_MAX / 4));
|
|
}
|
|
|
|
uint32_t FifoControllerBase::getFullFramesAvailable() const {
|
|
uint64_t writeCounter = getWriteCounter();
|
|
uint64_t readCounter = getReadCounter();
|
|
if (readCounter > writeCounter) {
|
|
return 0;
|
|
}
|
|
uint64_t delta = writeCounter - readCounter;
|
|
if (delta >= mTotalFrames) {
|
|
return mTotalFrames;
|
|
}
|
|
// delta is now guaranteed to fit within the range of a uint32_t
|
|
return static_cast<uint32_t>(delta);
|
|
}
|
|
|
|
uint32_t FifoControllerBase::getReadIndex() const {
|
|
// % works with non-power of two sizes
|
|
return static_cast<uint32_t>(getReadCounter() % mTotalFrames);
|
|
}
|
|
|
|
void FifoControllerBase::advanceReadIndex(uint32_t numFrames) {
|
|
incrementReadCounter(numFrames);
|
|
}
|
|
|
|
uint32_t FifoControllerBase::getEmptyFramesAvailable() const {
|
|
return static_cast<uint32_t>(mTotalFrames - getFullFramesAvailable());
|
|
}
|
|
|
|
uint32_t FifoControllerBase::getWriteIndex() const {
|
|
// % works with non-power of two sizes
|
|
return static_cast<uint32_t>(getWriteCounter() % mTotalFrames);
|
|
}
|
|
|
|
void FifoControllerBase::advanceWriteIndex(uint32_t numFrames) {
|
|
incrementWriteCounter(numFrames);
|
|
}
|
|
|
|
} // namespace oboe
|