diff options
| -rw-r--r-- | libdimension/cone.c | 113 |
1 files changed, 68 insertions, 45 deletions
diff --git a/libdimension/cone.c b/libdimension/cone.c index 688b19b..2cd5c8a 100644 --- a/libdimension/cone.c +++ b/libdimension/cone.c @@ -29,7 +29,6 @@ /** Cone payload type. */ typedef struct dmnsn_cone_payload { double r1, r2; - bool open; } dmnsn_cone_payload; /** Intersection callback for a cone. */ @@ -66,47 +65,6 @@ dmnsn_cone_intersection_fn(const dmnsn_object *cone, dmnsn_line l, p = dmnsn_line_point(l, t); } - if (!payload->open && l.n.y) { - /* Test for cap intersections */ - double tcap1 = (-1.0 - l.x0.y)/l.n.y; - double tcap2 = (+1.0 - l.x0.y)/l.n.y; - - double tcap, r; - dmnsn_vector norm; - if (tcap1 < tcap2) { - tcap = tcap1; - r = r1; - norm = dmnsn_new_vector(0.0, -1.0, 0.0); - } else { - tcap = tcap2; - r = r2; - norm = dmnsn_new_vector(0.0, 1.0, 0.0); - } - dmnsn_vector pcap = dmnsn_line_point(l, tcap); - - if (tcap < 0.0 || pcap.x*pcap.x + pcap.z*pcap.z >= r*r) { - if (tcap2 <= tcap1) { - tcap = tcap1; - r = r1; - norm = dmnsn_new_vector(0.0, -1.0, 0.0); - } else { - tcap = tcap2; - r = r2; - norm = dmnsn_new_vector(0.0, 1.0, 0.0); - } - pcap = dmnsn_line_point(l, tcap); - } - - if (tcap >= 0.0 - && (tcap < t || p.y <= -1.0 || p.y >= 1.0) - && pcap.x*pcap.x + pcap.z*pcap.z < r*r) - { - intersection->t = tcap; - intersection->normal = norm; - return true; - } - } - if (t >= 0.0 && p.y > -1.0 && p.y < 1.0) { dmnsn_vector norm = dmnsn_vector_normalized( dmnsn_new_vector(p.x, -(r2 - r1)*sqrt(p.x*p.x + p.z*p.z)/2.0, p.z) @@ -131,6 +89,50 @@ dmnsn_cone_inside_fn(const dmnsn_object *cone, dmnsn_vector point) && point.y > -1.0 && point.y < 1.0; } +/** Cone cap intersection function. */ +static bool +dmnsn_cone_cap_intersection_fn(const dmnsn_object *cap, dmnsn_line l, + dmnsn_intersection *intersection) +{ + if (l.n.y != 0.0) { + double *rptr = cap->ptr, r = *rptr; + double t = -l.x0.y/l.n.y; + dmnsn_vector p = dmnsn_line_point(l, t); + if (t >= 0.0 && p.x*p.x + p.z*p.z <= r*r) { + intersection->t = t; + intersection->normal = dmnsn_new_vector(0.0, -1.0, 0.0); + return true; + } + } + + return false; +} + +/** Inside callback for a cone cap. */ +static bool +dmnsn_cone_cap_inside_fn(const dmnsn_object *cone, dmnsn_vector point) +{ + return false; +} + +/** Allocate a new cone cap. */ +dmnsn_object * +dmnsn_new_cone_cap(double r) +{ + dmnsn_object *cap = dmnsn_new_object(); + cap->intersection_fn = dmnsn_cone_cap_intersection_fn; + cap->inside_fn = dmnsn_cone_cap_inside_fn; + cap->bounding_box.min = dmnsn_new_vector(-r, 0.0, -r); + cap->bounding_box.max = dmnsn_new_vector(+r, 0.0, +r); + + double *payload = dmnsn_malloc(sizeof(double)); + *payload = r; + cap->ptr = payload; + cap->free_fn = dmnsn_free; + + return cap; +} + /* Allocate a new cone object */ dmnsn_object * dmnsn_new_cone(double r1, double r2, bool open) @@ -143,10 +145,31 @@ dmnsn_new_cone(double r1, double r2, bool open) cone->bounding_box.max = dmnsn_new_vector(rmax, 1.0, rmax); dmnsn_cone_payload *payload = dmnsn_malloc(sizeof(dmnsn_cone_payload)); - payload->r1 = r1; - payload->r2 = r2; - payload->open = open; + payload->r1 = r1; + payload->r2 = r2; cone->ptr = payload; cone->free_fn = dmnsn_free; + + /* Implement closed cones as a union with the caps */ + if (!open) { + dmnsn_object *cap1 = dmnsn_new_cone_cap(r1); + dmnsn_object *cap2 = dmnsn_new_cone_cap(r2); + cap1->intrinsic_trans = dmnsn_translation_matrix( + dmnsn_new_vector(0.0, -1.0, 0.0) + ); + cap2->intrinsic_trans = dmnsn_translation_matrix( + dmnsn_new_vector(0.0, +1.0, 0.0) + ); + /* Flip the normal around for the top cap */ + cap2->intrinsic_trans.n[1][1] = -1.0; + + dmnsn_array *withcaps = dmnsn_new_array(sizeof(dmnsn_object *)); + dmnsn_array_push(withcaps, &cone); + dmnsn_array_push(withcaps, &cap1); + dmnsn_array_push(withcaps, &cap2); + cone = dmnsn_new_csg_union(withcaps); + dmnsn_delete_array(withcaps); + } + return cone; } |