static box_t get_box(const vec3_t *p0, const vec3_t *p1, const vec3_t *n,
float r, const plane_t *plane)
{
mat4_t rot;
box_t box;
if (p1 == NULL) {
box = bbox_from_extents(*p0, r, r, r);
box = box_swap_axis(box, 2, 0, 1);
return box;
}
if (r == 0) {
box = bbox_grow(bbox_from_points(*p0, *p1), 0.5, 0.5, 0.5);
// Apply the plane rotation.
rot = plane->mat;
rot.vecs[3] = vec4(0, 0, 0, 1);
mat4_imul(&box.mat, rot);
return box;
}
// Create a box for a line:
int i;
const vec3_t AXES[] = {vec3(1, 0, 0), vec3(0, 1, 0), vec3(0, 0, 1)};
box.mat = mat4_identity;
box.p = vec3_mix(*p0, *p1, 0.5);
box.d = vec3_sub(*p1, box.p);
for (i = 0; i < 3; i++) {
box.w = vec3_cross(box.d, AXES[i]);
if (vec3_norm2(box.w) > 0) break;
}
if (i == 3) return box;
box.w = vec3_mul(vec3_normalized(box.w), r);
box.h = vec3_mul(vec3_normalized(vec3_cross(box.d, box.w)), r);
return box;
}
box_t block_get_box(const block_t *block, bool exact)
{
box_t ret;
int x, y, z;
int xmin = N, xmax = 0, ymin = N, ymax = 0, zmin = N, zmax = 0;
if (!exact)
return bbox_from_extents(block->pos, N / 2, N / 2, N / 2);
BLOCK_ITER(x, y, z) {
if (BLOCK_AT(block, x, y, z).a) {
xmin = min(xmin, x);
ymin = min(ymin, y);
zmin = min(zmin, z);
xmax = max(xmax, x);
ymax = max(ymax, y);
zmax = max(zmax, z);
}
}
if (xmin > xmax) return box_null();
ret = bbox_from_points(vec3(xmin - 0.5, ymin - 0.5, zmin - 0.5),
vec3(xmax + 0.5, ymax + 0.5, zmax + 0.5));
vec3_iadd(&ret.p, block->pos);
vec3_isub(&ret.p, vec3(N / 2 - 0.5, N / 2 - 0.5, N / 2 - 0.5));
return ret;
}
