From 8fed0cea862554f1d8316c2244e6d94f691abad6 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Sun, 15 Aug 2010 00:18:09 -0600 Subject: Make dmnsn_vector_axis_angle() handle edge cases. --- libdimension/geometry.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'libdimension/geometry.c') diff --git a/libdimension/geometry.c b/libdimension/geometry.c index 26ca628..6b1019b 100644 --- a/libdimension/geometry.c +++ b/libdimension/geometry.c @@ -87,8 +87,12 @@ dmnsn_vector_axis_angle(dmnsn_vector v1, dmnsn_vector v2, dmnsn_vector axis) dmnsn_vector d = dmnsn_vector_sub(v1, v2); dmnsn_vector proj = dmnsn_vector_add(dmnsn_vector_proj(d, axis), v2); + double projn = dmnsn_vector_norm(proj); + if (!projn) + return 0.0; + double c = dmnsn_vector_dot(dmnsn_vector_normalize(v1), - dmnsn_vector_normalize(proj)); + dmnsn_vector_div(proj, projn)); double angle = acos(c); if (dmnsn_vector_dot(dmnsn_vector_cross(v1, proj), axis) > 0) { -- cgit v1.2.3