/*
* _alcSpeakerMove( ALuint cid )
*
* Moves speakers for context named by cid, using listener orientation and
* position as modifiers.
*
* If cid is invalid, set ALC_INVALID_CONTEXT.
*
* assumes context cid is locked
*
* FIXME:
* please check my math
*/
void _alcSpeakerMove( ALuint cid ) {
AL_context *cc;
ALfloat vec[3];
ALfloat *pos; /* listener position */
ALfloat *ori; /* listener orientation */
ALfloat ipos[3]; /* inverse listener position */
ALuint i;
ALfloat m[3][3];
ALfloat pm[3];
ALfloat rm[3];
cc = _alcGetContext( cid );
if(cc == NULL) {
_alDebug(ALD_CONTEXT, __FILE__, __LINE__,
"_alcSpeakerMove: invalid context id %d", cid);
_alcSetError( ALC_INVALID_CONTEXT );
return;
}
pos = cc->listener.position;
ori = cc->listener.orientation;
_alVectorCrossProduct(vec, ori + 0, ori + 3);
_alVectorNormalize(m[0], vec);
_alVectorCrossProduct(vec, m[0], ori + 0);
_alVectorNormalize(m[1], vec);
_alVectorNormalize(m[2], ori + 0);
/* reset speaker position */
_alcSpeakerInit(cid);
_alVectorInverse( ipos, cc->listener.position );
/* rotate about at and up vectors */
for(i = 0; i < _alcGetNumSpeakers(cid); i++) {
_alVectorTranslate(pm,
cc->_speaker_pos[i].pos, ipos);
_alVecMatrixMulA3(rm, pm, m);
_alVectorTranslate(cc->_speaker_pos[i].pos,
rm, pos);
}
_alDebug(ALD_MATH, __FILE__, __LINE__,
"SpAdj: l/r [%f|%f|%f] [%f|%f|%f]",
cc->_speaker_pos[0].pos[0],
cc->_speaker_pos[0].pos[1],
cc->_speaker_pos[0].pos[2],
cc->_speaker_pos[1].pos[0],
cc->_speaker_pos[1].pos[1],
cc->_speaker_pos[1].pos[2]);
return;
}
/*
* _alVectorDotp( const ALfloat *origin, const ALfloat *v1,
* const ALfloat *v2 )
*
* Returns dot product between v1 and v2, with origin at origin.
*/
ALfloat _alVectorDotp( const ALfloat *origin, const ALfloat *v1,
const ALfloat *v2 ) {
ALfloat o_inverse[3];
ALfloat v1_trans[3];
ALfloat v2_trans[3];
ALfloat retval = 0.0f;
_alVectorInverse( o_inverse, origin );
_alVectorTranslate( v1_trans, v1, o_inverse );
_alVectorTranslate( v2_trans, v2, o_inverse );
retval += v1_trans[0] * v2_trans[0];
retval += v1_trans[1] * v2_trans[1];
retval += v1_trans[2] * v2_trans[2];
return retval;
}
