ebiten/audio/internal/oboe/oboe_flowgraph_FlowgraphUtilities_android.h
2021-05-30 05:07:16 +09:00

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/*
* Copyright 2020 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.
*/
#ifndef FLOWGRAPH_UTILITIES_H
#define FLOWGRAPH_UTILITIES_H
#include <unistd.h>
using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
class FlowgraphUtilities {
public:
// This was copied from audio_utils/primitives.h
/**
* Convert a single-precision floating point value to a Q0.31 integer value.
* Rounds to nearest, ties away from 0.
*
* Values outside the range [-1.0, 1.0) are properly clamped to -2147483648 and 2147483647,
* including -Inf and +Inf. NaN values are considered undefined, and behavior may change
* depending on hardware and future implementation of this function.
*/
static int32_t clamp32FromFloat(float f)
{
static const float scale = (float)(1UL << 31);
static const float limpos = 1.;
static const float limneg = -1.;
if (f <= limneg) {
return -0x80000000; /* or 0x80000000 */
} else if (f >= limpos) {
return 0x7fffffff;
}
f *= scale;
/* integer conversion is through truncation (though int to float is not).
* ensure that we round to nearest, ties away from 0.
*/
return f > 0 ? f + 0.5 : f - 0.5;
}
};
#endif // FLOWGRAPH_UTILITIES_H