mirror of
https://github.com/WinampDesktop/winamp.git
synced 2024-12-18 23:35:51 +01:00
64 lines
2.3 KiB
C
64 lines
2.3 KiB
C
/*
|
|
* Mixer.h
|
|
* -------
|
|
* Purpose: Basic mixer constants
|
|
* Notes : (currently none)
|
|
* Authors: OpenMPT Devs
|
|
* The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
|
|
*/
|
|
|
|
|
|
#pragma once
|
|
|
|
#include "openmpt/all/BuildSettings.hpp"
|
|
|
|
#include "openmpt/soundbase/MixSample.hpp"
|
|
|
|
OPENMPT_NAMESPACE_BEGIN
|
|
|
|
#define MPT_INTMIXER
|
|
|
|
#ifdef MPT_INTMIXER
|
|
using mixsample_t = MixSampleIntTraits::sample_type;
|
|
enum { MIXING_FILTER_PRECISION = MixSampleIntTraits::filter_precision_bits }; // Fixed point resonant filter bits
|
|
#else
|
|
using mixsample_t = MixSampleFloat;
|
|
#endif
|
|
enum { MIXING_ATTENUATION = MixSampleIntTraits::mix_headroom_bits };
|
|
enum { MIXING_FRACTIONAL_BITS = MixSampleIntTraits::mix_fractional_bits };
|
|
|
|
inline constexpr float MIXING_SCALEF = MixSampleIntTraits::mix_scale<float>;
|
|
|
|
#ifdef MPT_INTMIXER
|
|
static_assert(sizeof(mixsample_t) == 4);
|
|
static_assert(MIXING_FILTER_PRECISION == 24);
|
|
static_assert(MIXING_ATTENUATION == 4);
|
|
static_assert(MIXING_FRACTIONAL_BITS == 27);
|
|
static_assert(MixSampleIntTraits::mix_clip_max == int32(0x7FFFFFF));
|
|
static_assert(MixSampleIntTraits::mix_clip_min == (0 - int32(0x7FFFFFF)));
|
|
static_assert(MIXING_SCALEF == 134217728.0f);
|
|
#else
|
|
static_assert(sizeof(mixsample_t) == 4);
|
|
#endif
|
|
|
|
#define MIXBUFFERSIZE 512
|
|
#define NUMMIXINPUTBUFFERS 4
|
|
|
|
#define VOLUMERAMPPRECISION 12 // Fractional bits in volume ramp variables
|
|
|
|
// The absolute maximum number of sampling points any interpolation algorithm is going to look at in any direction from the current sampling point
|
|
// Currently, the maximum is 4 sampling points forwards and 3 sampling points backwards (Polyphase / FIR algorithms).
|
|
// Hence, this value must be at least 4.
|
|
inline constexpr uint8 InterpolationMaxLookahead = 4;
|
|
// While we could directly use the previous value in various places such as the interpolation wrap-around handling at loop points,
|
|
// choosing a higher value (e.g. 16) will reduce CPU usage when using many extremely short (length < 16) samples.
|
|
inline constexpr uint8 InterpolationLookaheadBufferSize = 16;
|
|
|
|
static_assert(InterpolationLookaheadBufferSize >= InterpolationMaxLookahead);
|
|
|
|
// Maximum size of a sampling point of a sample, in bytes.
|
|
// The biggest sampling point size is currently 16-bit stereo = 2 * 2 bytes.
|
|
inline constexpr uint8 MaxSamplingPointSize = 4;
|
|
|
|
OPENMPT_NAMESPACE_END
|