diff options
Diffstat (limited to 'ctranslate.c')
| -rw-r--r-- | ctranslate.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/ctranslate.c b/ctranslate.c new file mode 100644 index 0000000..f7dfe64 --- /dev/null +++ b/ctranslate.c @@ -0,0 +1,41 @@ +#include "ctranslate.h" + +#include <math.h> + +// TODO remove dublicate pi definitions +#define PI 3.14159265359 + +void csystem_init(csystem_t *cs, vector_t *up) +{ + cs->up = up; + + // Create new coordinate system where N is up. To do this we need two more vectors for the other axises. + // Create the 2. by setting x or y to 0 + if (up->x > up->y) { + vector_set(&cs->ax, up->z, 0, -up->x); + } else { + vector_set(&cs->ax, 0, -up->z, up->y); + } + // Normalice + vector_scale_inv(&cs->ax, &cs->ax, vector_len(&cs->ax)); + + // Create the 3. axis by taking the cross of the other + vector_cross(&cs->az, up, &cs->ax); +} + +void csystem_calc_real(csystem_t *cs, vector_t *inside, vector_t *real) +{ + vector_set(real, inside->x * cs->ax.x + inside->y * cs->up->x + inside->z * cs->az.x, + inside->x * cs->ax.y + inside->y * cs->up->y + inside->z * cs->az.y, + inside->x * cs->ax.z + inside->y * cs->up->z + inside->z * cs->az.z); +} + +void csystem_hemisphere_random(csystem_t *cs, COORD_T r1, COORD_T r2, vector_t *out) +{ + COORD_T sinTheta = sqrt(1 - r1 * r1); + COORD_T phi = 2 * PI * r2; + + // Calculate the random direction vector + vector_set(out, sinTheta * cos(phi), r1, sinTheta * sin(phi)); +} + |