diff options
| -rw-r--r-- | libdimension/cylinder.c | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/libdimension/cylinder.c b/libdimension/cylinder.c index 2020fa2..159d520 100644 --- a/libdimension/cylinder.c +++ b/libdimension/cylinder.c @@ -41,9 +41,8 @@ dmnsn_new_cylinder(bool open) cylinder->inside_fn = &dmnsn_cylinder_inside_fn; cylinder->bounding_box.min = dmnsn_new_vector(-1.0, -1.0, -1.0); cylinder->bounding_box.max = dmnsn_new_vector(1.0, 1.0, 1.0); - if (open) { - cylinder->ptr = cylinder; /* (bool)cyliner->ptr == open */ - } + /* (bool)cyliner->ptr == open */ + cylinder->ptr = open ? cylinder : NULL; return cylinder; } @@ -69,16 +68,26 @@ dmnsn_cylinder_intersection_fn(const dmnsn_object *cylinder, dmnsn_line line, p = dmnsn_line_point(l, t); } - if (!cylinder->ptr) { + if (!cylinder->ptr && l.n.y) { /* Test for cap intersections */ - double tcap = (-1.0 - l.x0.y)/l.n.y; + double tcap1 = (-1.0 - l.x0.y)/l.n.y; + double tcap2 = (+1.0 - l.x0.y)/l.n.y; + + double tcap; + dmnsn_vector norm; + if (tcap1 < tcap2) { + tcap = tcap1; + norm = dmnsn_new_vector(0.0, -1.0, 0.0); + } else { + tcap = tcap2; + norm = dmnsn_new_vector(0.0, 1.0, 0.0); + } dmnsn_vector pcap = dmnsn_line_point(l, tcap); - dmnsn_vector norm = dmnsn_new_vector(0.0, -1.0, 0.0); if (tcap < 0.0 || pcap.x*pcap.x + pcap.z*pcap.z >= 1.0) { - tcap = (+1.0 - l.x0.y)/l.n.y; + tcap = dmnsn_max(tcap1, tcap2); pcap = dmnsn_line_point(l, tcap); - norm = dmnsn_new_vector(0.0, 1.0, 0.0); + norm = dmnsn_vector_negate(norm); } if (tcap >= 0.0 |