mirror of
https://thingvellir.net/git/overte
synced 2025-03-27 23:52:03 +01:00
141 lines
4.3 KiB
C++
141 lines
4.3 KiB
C++
//
|
|
// AudioPan.h
|
|
// hifi
|
|
//
|
|
// Created by Craig Hansen-Sturm on 9/1/14.
|
|
// Copyright 2014 High Fidelity, Inc.
|
|
//
|
|
// Distributed under the Apache License, Version 2.0.
|
|
// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
|
|
//
|
|
|
|
#ifndef hifi_AudioPan_h
|
|
#define hifi_AudioPan_h
|
|
|
|
class AudioPan
|
|
{
|
|
float32_t _pan;
|
|
float32_t _gainLeft;
|
|
float32_t _gainRight;
|
|
|
|
static float32_t ONE_MINUS_EPSILON;
|
|
static float32_t ZERO_PLUS_EPSILON;
|
|
static float32_t ONE_HALF_MINUS_EPSILON;
|
|
static float32_t ONE_HALF_PLUS_EPSILON;
|
|
|
|
void updateCoefficients() {
|
|
|
|
// implement constant power sin^2 + cos^2 = 1 panning law
|
|
|
|
if (_pan >= ONE_MINUS_EPSILON) { // full right
|
|
_gainLeft = 0.0f;
|
|
_gainRight = 1.0f;
|
|
}
|
|
else if (_pan <= ZERO_PLUS_EPSILON) { // full left
|
|
_gainLeft = 1.0f;
|
|
_gainRight = 0.0f;
|
|
}
|
|
else if ((_pan >= ONE_HALF_MINUS_EPSILON) && (_pan <= ONE_HALF_PLUS_EPSILON)) { // center
|
|
_gainLeft = 1.0f / SQUARE_ROOT_OF_2;
|
|
_gainRight = 1.0f / SQUARE_ROOT_OF_2;
|
|
}
|
|
else { // intermediate cases
|
|
_gainLeft = cosf( TWO_PI * _pan );
|
|
_gainRight = sinf( TWO_PI * _pan );
|
|
}
|
|
}
|
|
|
|
public:
|
|
AudioPan() {
|
|
initialize();
|
|
}
|
|
|
|
~AudioPan() {
|
|
finalize();
|
|
}
|
|
|
|
void initialize() {
|
|
setParameters(0.5f);
|
|
}
|
|
|
|
void finalize() {
|
|
}
|
|
|
|
void reset() {
|
|
initialize();
|
|
}
|
|
|
|
void setParameters(const float32_t pan) {
|
|
// pan ranges between 0.0 and 1.0f inclusive. 0.5f is midpoint between full left and full right
|
|
_pan = std::min(std::max(pan, 0.0f), 1.0f);
|
|
updateCoefficients();
|
|
}
|
|
|
|
void getParameters(float32_t& pan) {
|
|
pan = _pan;
|
|
}
|
|
|
|
void render(AudioBufferFloat32& frameBuffer) {
|
|
|
|
if (frameBuffer.getChannelCount() != 2) {
|
|
return;
|
|
}
|
|
|
|
float32_t** samples = frameBuffer.getFrameData();
|
|
|
|
bool frameAlignment16 = (frameBuffer.getFrameCount() & 0x0F) == 0;
|
|
if (frameAlignment16) {
|
|
|
|
if (frameBuffer.getChannelCount() == 2) {
|
|
|
|
for (uint16_t i = 0; i < frameBuffer.getFrameCount(); i += 16) {
|
|
samples[0][i + 0] *= _gainLeft;
|
|
samples[0][i + 1] *= _gainLeft;
|
|
samples[0][i + 2] *= _gainLeft;
|
|
samples[0][i + 3] *= _gainLeft;
|
|
samples[0][i + 4] *= _gainLeft;
|
|
samples[0][i + 5] *= _gainLeft;
|
|
samples[0][i + 6] *= _gainLeft;
|
|
samples[0][i + 7] *= _gainLeft;
|
|
samples[0][i + 8] *= _gainLeft;
|
|
samples[0][i + 9] *= _gainLeft;
|
|
samples[0][i + 10] *= _gainLeft;
|
|
samples[0][i + 11] *= _gainLeft;
|
|
samples[0][i + 12] *= _gainLeft;
|
|
samples[0][i + 13] *= _gainLeft;
|
|
samples[0][i + 14] *= _gainLeft;
|
|
samples[0][i + 15] *= _gainLeft;
|
|
samples[1][i + 0] *= _gainRight;
|
|
samples[1][i + 1] *= _gainRight;
|
|
samples[1][i + 2] *= _gainRight;
|
|
samples[1][i + 3] *= _gainRight;
|
|
samples[1][i + 4] *= _gainRight;
|
|
samples[1][i + 5] *= _gainRight;
|
|
samples[1][i + 6] *= _gainRight;
|
|
samples[1][i + 7] *= _gainRight;
|
|
samples[1][i + 8] *= _gainRight;
|
|
samples[1][i + 9] *= _gainRight;
|
|
samples[1][i + 10] *= _gainRight;
|
|
samples[1][i + 11] *= _gainRight;
|
|
samples[1][i + 12] *= _gainRight;
|
|
samples[1][i + 13] *= _gainRight;
|
|
samples[1][i + 14] *= _gainRight;
|
|
samples[1][i + 15] *= _gainRight;
|
|
}
|
|
}
|
|
else {
|
|
assert("unsupported channel format");
|
|
}
|
|
}
|
|
else {
|
|
for (uint16_t i = 0; i < frameBuffer.getFrameCount(); i += 1) {
|
|
samples[0][i] *= _gainLeft;
|
|
samples[1][i] *= _gainRight;
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
#endif // AudioPan_h
|
|
|
|
|