diff options
Diffstat (limited to 'Alc/hrtf.c')
| -rw-r--r-- | Alc/hrtf.c | 222 |
1 files changed, 12 insertions, 210 deletions
@@ -58,10 +58,6 @@ struct Hrtf { static const ALchar magicMarker00[8] = "MinPHR00"; static const ALchar magicMarker01[8] = "MinPHR01"; -/* First value for pass-through coefficients (remaining are 0), used for omni- - * directional sounds. */ -static const ALfloat PassthruCoeff = 32767.0f * 0.707106781187f/*sqrt(0.5)*/; - static struct Hrtf *LoadedHrtfs = NULL; /* Calculate the elevation indices given the polar elevation in radians. @@ -88,45 +84,12 @@ static void CalcAzIndices(ALuint azcount, ALfloat az, ALuint *azidx, ALfloat *az *azmu = az - floorf(az); } -/* Calculates the normalized HRTF transition factor (delta) from the changes - * in gain and listener to source angle between updates. The result is a - * normalized delta factor that can be used to calculate moving HRIR stepping - * values. - */ -ALfloat CalcHrtfDelta(ALfloat oldGain, ALfloat newGain, const ALfloat olddir[3], const ALfloat newdir[3]) -{ - ALfloat gainChange, angleChange, change; - - // Calculate the normalized dB gain change. - newGain = maxf(newGain, 0.0001f); - oldGain = maxf(oldGain, 0.0001f); - gainChange = fabsf(log10f(newGain / oldGain) / log10f(0.0001f)); - - // Calculate the angle change only when there is enough gain to notice it. - angleChange = 0.0f; - if(gainChange > 0.0001f || newGain > 0.0001f) - { - // No angle change when the directions are equal or degenerate (when - // both have zero length). - if(newdir[0] != olddir[0] || newdir[1] != olddir[1] || newdir[2] != olddir[2]) - { - ALfloat dotp = olddir[0]*newdir[0] + olddir[1]*newdir[1] + olddir[2]*newdir[2]; - angleChange = acosf(clampf(dotp, -1.0f, 1.0f)) / F_PI; - } - } - - // Use the largest of the two changes for the delta factor, and apply a - // significance shaping function to it. - change = maxf(angleChange * 25.0f, gainChange) * 2.0f; - return minf(change, 1.0f); -} - /* Calculates static HRIR coefficients and delays for the given polar * elevation and azimuth in radians. Linear interpolation is used to * increase the apparent resolution of the HRIR data set. The coefficients * are also normalized and attenuated by the specified gain. */ -void GetLerpedHrtfCoeffs(const struct Hrtf *Hrtf, ALfloat elevation, ALfloat azimuth, ALfloat dirfact, ALfloat gain, ALfloat (*coeffs)[2], ALuint *delays) +void GetLerpedHrtfCoeffs(const struct Hrtf *Hrtf, ALfloat elevation, ALfloat azimuth, ALfloat (*coeffs)[2], ALuint *delays) { ALuint evidx[2], lidx[4], ridx[4]; ALfloat mu[3], blend[4]; @@ -158,12 +121,12 @@ void GetLerpedHrtfCoeffs(const struct Hrtf *Hrtf, ALfloat elevation, ALfloat azi blend[3] = ( mu[1]) * ( mu[2]); /* Calculate the HRIR delays using linear interpolation. */ - delays[0] = fastf2u((Hrtf->delays[lidx[0]]*blend[0] + Hrtf->delays[lidx[1]]*blend[1] + - Hrtf->delays[lidx[2]]*blend[2] + Hrtf->delays[lidx[3]]*blend[3]) * - dirfact + 0.5f) << HRTFDELAY_BITS; - delays[1] = fastf2u((Hrtf->delays[ridx[0]]*blend[0] + Hrtf->delays[ridx[1]]*blend[1] + - Hrtf->delays[ridx[2]]*blend[2] + Hrtf->delays[ridx[3]]*blend[3]) * - dirfact + 0.5f) << HRTFDELAY_BITS; + delays[0] = fastf2u(Hrtf->delays[lidx[0]]*blend[0] + Hrtf->delays[lidx[1]]*blend[1] + + Hrtf->delays[lidx[2]]*blend[2] + Hrtf->delays[lidx[3]]*blend[3] + + 0.5f); + delays[1] = fastf2u(Hrtf->delays[ridx[0]]*blend[0] + Hrtf->delays[ridx[1]]*blend[1] + + Hrtf->delays[ridx[2]]*blend[2] + Hrtf->delays[ridx[3]]*blend[3] + + 0.5f); /* Calculate the sample offsets for the HRIR indices. */ lidx[0] *= Hrtf->irSize; @@ -175,183 +138,22 @@ void GetLerpedHrtfCoeffs(const struct Hrtf *Hrtf, ALfloat elevation, ALfloat azi ridx[2] *= Hrtf->irSize; ridx[3] *= Hrtf->irSize; - /* Calculate the normalized and attenuated HRIR coefficients using linear - * interpolation when there is enough gain to warrant it. Zero the - * coefficients if gain is too low. - */ - if(gain > 0.0001f) + for(i = 0;i < Hrtf->irSize;i++) { ALfloat c; - - gain *= 1.0f/32767.0f; - - i = 0; c = (Hrtf->coeffs[lidx[0]+i]*blend[0] + Hrtf->coeffs[lidx[1]+i]*blend[1] + Hrtf->coeffs[lidx[2]+i]*blend[2] + Hrtf->coeffs[lidx[3]+i]*blend[3]); - coeffs[i][0] = lerp(PassthruCoeff, c, dirfact) * gain; + coeffs[i][0] = c * (1.0f/32767.0f); c = (Hrtf->coeffs[ridx[0]+i]*blend[0] + Hrtf->coeffs[ridx[1]+i]*blend[1] + Hrtf->coeffs[ridx[2]+i]*blend[2] + Hrtf->coeffs[ridx[3]+i]*blend[3]); - coeffs[i][1] = lerp(PassthruCoeff, c, dirfact) * gain; - - for(i = 1;i < Hrtf->irSize;i++) - { - c = (Hrtf->coeffs[lidx[0]+i]*blend[0] + Hrtf->coeffs[lidx[1]+i]*blend[1] + - Hrtf->coeffs[lidx[2]+i]*blend[2] + Hrtf->coeffs[lidx[3]+i]*blend[3]); - coeffs[i][0] = lerp(0.0f, c, dirfact) * gain; - c = (Hrtf->coeffs[ridx[0]+i]*blend[0] + Hrtf->coeffs[ridx[1]+i]*blend[1] + - Hrtf->coeffs[ridx[2]+i]*blend[2] + Hrtf->coeffs[ridx[3]+i]*blend[3]); - coeffs[i][1] = lerp(0.0f, c, dirfact) * gain; - } + coeffs[i][1] = c * (1.0f/32767.0f); } - else - { - for(i = 0;i < Hrtf->irSize;i++) - { - coeffs[i][0] = 0.0f; - coeffs[i][1] = 0.0f; - } - } -} - -/* Calculates the moving HRIR target coefficients, target delays, and - * stepping values for the given polar elevation and azimuth in radians. - * Linear interpolation is used to increase the apparent resolution of the - * HRIR data set. The coefficients are also normalized and attenuated by the - * specified gain. Stepping resolution and count is determined using the - * given delta factor between 0.0 and 1.0. - */ -ALuint GetMovingHrtfCoeffs(const struct Hrtf *Hrtf, ALfloat elevation, ALfloat azimuth, ALfloat dirfact, ALfloat gain, ALfloat delta, ALint counter, ALfloat (*coeffs)[2], ALuint *delays, ALfloat (*coeffStep)[2], ALint *delayStep) -{ - ALuint evidx[2], lidx[4], ridx[4]; - ALfloat mu[3], blend[4]; - ALfloat left, right; - ALfloat step; - ALuint i; - - /* Claculate elevation indices and interpolation factor. */ - CalcEvIndices(Hrtf->evCount, elevation, evidx, &mu[2]); - - for(i = 0;i < 2;i++) - { - ALuint azcount = Hrtf->azCount[evidx[i]]; - ALuint evoffset = Hrtf->evOffset[evidx[i]]; - ALuint azidx[2]; - - /* Calculate azimuth indices and interpolation factor for this elevation. */ - CalcAzIndices(azcount, azimuth, azidx, &mu[i]); - - /* Calculate a set of linear HRIR indices for left and right channels. */ - lidx[i*2 + 0] = evoffset + azidx[0]; - lidx[i*2 + 1] = evoffset + azidx[1]; - ridx[i*2 + 0] = evoffset + ((azcount-azidx[0]) % azcount); - ridx[i*2 + 1] = evoffset + ((azcount-azidx[1]) % azcount); - } - - // Calculate the stepping parameters. - delta = maxf(floorf(delta*(Hrtf->sampleRate*0.015f) + 0.5f), 1.0f); - step = 1.0f / delta; - - /* Calculate 4 blending weights for 2D bilinear interpolation. */ - blend[0] = (1.0f-mu[0]) * (1.0f-mu[2]); - blend[1] = ( mu[0]) * (1.0f-mu[2]); - blend[2] = (1.0f-mu[1]) * ( mu[2]); - blend[3] = ( mu[1]) * ( mu[2]); - - /* Calculate the HRIR delays using linear interpolation. Then calculate - * the delay stepping values using the target and previous running - * delays. - */ - left = (ALfloat)(delays[0] - (delayStep[0] * counter)); - right = (ALfloat)(delays[1] - (delayStep[1] * counter)); - - delays[0] = fastf2u((Hrtf->delays[lidx[0]]*blend[0] + Hrtf->delays[lidx[1]]*blend[1] + - Hrtf->delays[lidx[2]]*blend[2] + Hrtf->delays[lidx[3]]*blend[3]) * - dirfact + 0.5f) << HRTFDELAY_BITS; - delays[1] = fastf2u((Hrtf->delays[ridx[0]]*blend[0] + Hrtf->delays[ridx[1]]*blend[1] + - Hrtf->delays[ridx[2]]*blend[2] + Hrtf->delays[ridx[3]]*blend[3]) * - dirfact + 0.5f) << HRTFDELAY_BITS; - - delayStep[0] = fastf2i(step * (delays[0] - left)); - delayStep[1] = fastf2i(step * (delays[1] - right)); - - /* Calculate the sample offsets for the HRIR indices. */ - lidx[0] *= Hrtf->irSize; - lidx[1] *= Hrtf->irSize; - lidx[2] *= Hrtf->irSize; - lidx[3] *= Hrtf->irSize; - ridx[0] *= Hrtf->irSize; - ridx[1] *= Hrtf->irSize; - ridx[2] *= Hrtf->irSize; - ridx[3] *= Hrtf->irSize; - - /* Calculate the normalized and attenuated target HRIR coefficients using - * linear interpolation when there is enough gain to warrant it. Zero - * the target coefficients if gain is too low. Then calculate the - * coefficient stepping values using the target and previous running - * coefficients. - */ - if(gain > 0.0001f) - { - ALfloat c; - - gain *= 1.0f/32767.0f; - - i = 0; - left = coeffs[i][0] - (coeffStep[i][0] * counter); - right = coeffs[i][1] - (coeffStep[i][1] * counter); - - c = (Hrtf->coeffs[lidx[0]+i]*blend[0] + Hrtf->coeffs[lidx[1]+i]*blend[1] + - Hrtf->coeffs[lidx[2]+i]*blend[2] + Hrtf->coeffs[lidx[3]+i]*blend[3]); - coeffs[i][0] = lerp(PassthruCoeff, c, dirfact) * gain; - c = (Hrtf->coeffs[ridx[0]+i]*blend[0] + Hrtf->coeffs[ridx[1]+i]*blend[1] + - Hrtf->coeffs[ridx[2]+i]*blend[2] + Hrtf->coeffs[ridx[3]+i]*blend[3]); - coeffs[i][1] = lerp(PassthruCoeff, c, dirfact) * gain; - - coeffStep[i][0] = step * (coeffs[i][0] - left); - coeffStep[i][1] = step * (coeffs[i][1] - right); - - for(i = 1;i < Hrtf->irSize;i++) - { - left = coeffs[i][0] - (coeffStep[i][0] * counter); - right = coeffs[i][1] - (coeffStep[i][1] * counter); - - c = (Hrtf->coeffs[lidx[0]+i]*blend[0] + Hrtf->coeffs[lidx[1]+i]*blend[1] + - Hrtf->coeffs[lidx[2]+i]*blend[2] + Hrtf->coeffs[lidx[3]+i]*blend[3]); - coeffs[i][0] = lerp(0.0f, c, dirfact) * gain; - c = (Hrtf->coeffs[ridx[0]+i]*blend[0] + Hrtf->coeffs[ridx[1]+i]*blend[1] + - Hrtf->coeffs[ridx[2]+i]*blend[2] + Hrtf->coeffs[ridx[3]+i]*blend[3]); - coeffs[i][1] = lerp(0.0f, c, dirfact) * gain; - - coeffStep[i][0] = step * (coeffs[i][0] - left); - coeffStep[i][1] = step * (coeffs[i][1] - right); - } - } - else - { - for(i = 0;i < Hrtf->irSize;i++) - { - left = coeffs[i][0] - (coeffStep[i][0] * counter); - right = coeffs[i][1] - (coeffStep[i][1] * counter); - - coeffs[i][0] = 0.0f; - coeffs[i][1] = 0.0f; - - coeffStep[i][0] = step * -left; - coeffStep[i][1] = step * -right; - } - } - - /* The stepping count is the number of samples necessary for the HRIR to - * complete its transition. The mixer will only apply stepping for this - * many samples. - */ - return fastf2u(delta); } static struct Hrtf *LoadHrtf00(FILE *f, ALuint deviceRate) { - const ALubyte maxDelay = SRC_HISTORY_LENGTH-1; + const ALubyte maxDelay = HRTF_HISTORY_LENGTH-1; struct Hrtf *Hrtf = NULL; ALboolean failed = AL_FALSE; ALuint rate = 0, irCount = 0; @@ -518,7 +320,7 @@ static struct Hrtf *LoadHrtf00(FILE *f, ALuint deviceRate) static struct Hrtf *LoadHrtf01(FILE *f, ALuint deviceRate) { - const ALubyte maxDelay = SRC_HISTORY_LENGTH-1; + const ALubyte maxDelay = HRTF_HISTORY_LENGTH-1; struct Hrtf *Hrtf = NULL; ALboolean failed = AL_FALSE; ALuint rate = 0, irCount = 0; |