diff options
| -rw-r--r-- | src/reax.c | 36 |
1 files changed, 36 insertions, 0 deletions
@@ -38,18 +38,54 @@ struct dvec struct reax_private { IndexingPrivate base; + struct dvec *directions; }; IndexingPrivate *reax_prepare() { struct reax_private *priv; + int ui, vi; + int samp; + double angular_inc; priv = calloc(1, sizeof(*priv)); if ( priv == NULL ) return NULL; priv->base.indm = INDEXING_REAX; + /* Decide on sampling interval */ + angular_inc = 0.03; /* From Steller (1997) */ + samp = (2.0 * M_PI) / angular_inc; + + priv->directions = malloc(samp*samp*sizeof(struct dvec)); + if ( priv == NULL) { + free(priv); + return NULL; + } + + for ( ui=0; ui<samp; ui++ ) { + for ( vi=0; vi<samp; vi++ ) { + + double u, v; + double th, ph; + struct dvec *dir; + + u = (double)ui/samp; + v = (double)vi/samp; + + th = 2.0 * M_PI * u; + ph = acos(2.0*v - 1.0); + + dir = &priv->directions[ui + vi*samp]; + + dir->x = cos(th) * sin(ph); + dir->y = sin(th) * sin(th); + dir->z = cos(ph); + + } + } + return (IndexingPrivate *)priv; } |