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-rw-r--r--OpenAL32/Include/alFilter.h134
1 files changed, 30 insertions, 104 deletions
diff --git a/OpenAL32/Include/alFilter.h b/OpenAL32/Include/alFilter.h
index 3c65fd9f..2634d5e8 100644
--- a/OpenAL32/Include/alFilter.h
+++ b/OpenAL32/Include/alFilter.h
@@ -1,9 +1,8 @@
#ifndef _AL_FILTER_H_
#define _AL_FILTER_H_
-#include "alMain.h"
-
-#include "math_defs.h"
+#include "AL/alc.h"
+#include "AL/al.h"
#ifdef __cplusplus
extern "C" {
@@ -13,86 +12,28 @@ extern "C" {
#define HIGHPASSFREQREF (250.0f)
-/* Filters implementation is based on the "Cookbook formulae for audio
- * EQ biquad filter coefficients" by Robert Bristow-Johnson
- * http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
- */
-/* Implementation note: For the shelf filters, the specified gain is for the
- * reference frequency, which is the centerpoint of the transition band. This
- * better matches EFX filter design. To set the gain for the shelf itself, use
- * the square root of the desired linear gain (or halve the dB gain).
- */
-
-typedef enum ALfilterType {
- /** EFX-style low-pass filter, specifying a gain and reference frequency. */
- ALfilterType_HighShelf,
- /** EFX-style high-pass filter, specifying a gain and reference frequency. */
- ALfilterType_LowShelf,
- /** Peaking filter, specifying a gain and reference frequency. */
- ALfilterType_Peaking,
-
- /** Low-pass cut-off filter, specifying a cut-off frequency. */
- ALfilterType_LowPass,
- /** High-pass cut-off filter, specifying a cut-off frequency. */
- ALfilterType_HighPass,
- /** Band-pass filter, specifying a center frequency. */
- ALfilterType_BandPass,
-} ALfilterType;
-
-typedef struct ALfilterState {
- ALfloat x[2]; /* History of two last input samples */
- ALfloat y[2]; /* History of two last output samples */
- ALfloat a[3]; /* Transfer function coefficients "a" */
- ALfloat b[3]; /* Transfer function coefficients "b" */
-
- void (*process)(struct ALfilterState *self, ALfloat *restrict dst, const ALfloat *src, ALuint numsamples);
-} ALfilterState;
-#define ALfilterState_process(a, ...) ((a)->process((a), __VA_ARGS__))
-
-/* Calculates the rcpQ (i.e. 1/Q) coefficient for shelving filters, using the
- * reference gain and shelf slope parameter.
- * 0 < gain
- * 0 < slope <= 1
- */
-inline ALfloat calc_rcpQ_from_slope(ALfloat gain, ALfloat slope)
-{
- return sqrtf((gain + 1.0f/gain)*(1.0f/slope - 1.0f) + 2.0f);
-}
-/* Calculates the rcpQ (i.e. 1/Q) coefficient for filters, using the frequency
- * multiple (i.e. ref_freq / sampling_freq) and bandwidth.
- * 0 < freq_mult < 0.5.
- */
-inline ALfloat calc_rcpQ_from_bandwidth(ALfloat freq_mult, ALfloat bandwidth)
-{
- ALfloat w0 = F_TAU * freq_mult;
- return 2.0f*sinhf(logf(2.0f)/2.0f*bandwidth*w0/sinf(w0));
-}
-
-void ALfilterState_clear(ALfilterState *filter);
-void ALfilterState_setParams(ALfilterState *filter, ALfilterType type, ALfloat gain, ALfloat freq_mult, ALfloat rcpQ);
+struct ALfilter;
-inline ALfloat ALfilterState_processSingle(ALfilterState *filter, ALfloat sample)
-{
- ALfloat outsmp;
+typedef struct ALfilterVtable {
+ void (*const setParami)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALint val);
+ void (*const setParamiv)(struct ALfilter *filter, ALCcontext *context, ALenum param, const ALint *vals);
+ void (*const setParamf)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALfloat val);
+ void (*const setParamfv)(struct ALfilter *filter, ALCcontext *context, ALenum param, const ALfloat *vals);
- outsmp = filter->b[0] * sample +
- filter->b[1] * filter->x[0] +
- filter->b[2] * filter->x[1] -
- filter->a[1] * filter->y[0] -
- filter->a[2] * filter->y[1];
- filter->x[1] = filter->x[0];
- filter->x[0] = sample;
- filter->y[1] = filter->y[0];
- filter->y[0] = outsmp;
+ void (*const getParami)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALint *val);
+ void (*const getParamiv)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALint *vals);
+ void (*const getParamf)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALfloat *val);
+ void (*const getParamfv)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALfloat *vals);
+} ALfilterVtable;
- return outsmp;
+#define DEFINE_ALFILTER_VTABLE(T) \
+const struct ALfilterVtable T##_vtable = { \
+ T##_setParami, T##_setParamiv, \
+ T##_setParamf, T##_setParamfv, \
+ T##_getParami, T##_getParamiv, \
+ T##_getParamf, T##_getParamfv, \
}
-void ALfilterState_processC(ALfilterState *filter, ALfloat *restrict dst, const ALfloat *src, ALuint numsamples);
-
-void ALfilterState_processPassthru(ALfilterState *filter, const ALfloat *src, ALuint numsamples);
-
-
typedef struct ALfilter {
// Filter type (AL_FILTER_NULL, ...)
ALenum type;
@@ -103,36 +44,21 @@ typedef struct ALfilter {
ALfloat GainLF;
ALfloat LFReference;
- void (*SetParami)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALint val);
- void (*SetParamiv)(struct ALfilter *filter, ALCcontext *context, ALenum param, const ALint *vals);
- void (*SetParamf)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALfloat val);
- void (*SetParamfv)(struct ALfilter *filter, ALCcontext *context, ALenum param, const ALfloat *vals);
-
- void (*GetParami)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALint *val);
- void (*GetParamiv)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALint *vals);
- void (*GetParamf)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALfloat *val);
- void (*GetParamfv)(struct ALfilter *filter, ALCcontext *context, ALenum param, ALfloat *vals);
+ const struct ALfilterVtable *vtab;
/* Self ID */
ALuint id;
} ALfilter;
-
-#define ALfilter_SetParami(x, c, p, v) ((x)->SetParami((x),(c),(p),(v)))
-#define ALfilter_SetParamiv(x, c, p, v) ((x)->SetParamiv((x),(c),(p),(v)))
-#define ALfilter_SetParamf(x, c, p, v) ((x)->SetParamf((x),(c),(p),(v)))
-#define ALfilter_SetParamfv(x, c, p, v) ((x)->SetParamfv((x),(c),(p),(v)))
-
-#define ALfilter_GetParami(x, c, p, v) ((x)->GetParami((x),(c),(p),(v)))
-#define ALfilter_GetParamiv(x, c, p, v) ((x)->GetParamiv((x),(c),(p),(v)))
-#define ALfilter_GetParamf(x, c, p, v) ((x)->GetParamf((x),(c),(p),(v)))
-#define ALfilter_GetParamfv(x, c, p, v) ((x)->GetParamfv((x),(c),(p),(v)))
-
-inline struct ALfilter *LookupFilter(ALCdevice *device, ALuint id)
-{ return (struct ALfilter*)LookupUIntMapKey(&device->FilterMap, id); }
-inline struct ALfilter *RemoveFilter(ALCdevice *device, ALuint id)
-{ return (struct ALfilter*)RemoveUIntMapKey(&device->FilterMap, id); }
-
-ALvoid ReleaseALFilters(ALCdevice *device);
+#define ALfilter_setParami(o, c, p, v) ((o)->vtab->setParami(o, c, p, v))
+#define ALfilter_setParamf(o, c, p, v) ((o)->vtab->setParamf(o, c, p, v))
+#define ALfilter_setParamiv(o, c, p, v) ((o)->vtab->setParamiv(o, c, p, v))
+#define ALfilter_setParamfv(o, c, p, v) ((o)->vtab->setParamfv(o, c, p, v))
+#define ALfilter_getParami(o, c, p, v) ((o)->vtab->getParami(o, c, p, v))
+#define ALfilter_getParamf(o, c, p, v) ((o)->vtab->getParamf(o, c, p, v))
+#define ALfilter_getParamiv(o, c, p, v) ((o)->vtab->getParamiv(o, c, p, v))
+#define ALfilter_getParamfv(o, c, p, v) ((o)->vtab->getParamfv(o, c, p, v))
+
+void ReleaseALFilters(ALCdevice *device);
#ifdef __cplusplus
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-24 08:35:49 +0000