star-3d

commit 043dc3be804f2240d9d3a804ec02181730d00ea5
parent b4e2464b1d662278b7ac939699986c4626375d79
Author: Vincent Forest <vincent.forest@meso-star.com>
Date:   Mon, 20 Apr 2020 09:53:53 +0200

Handle a precision issue in closest_point_triangle

Ensure that the returned barycentric coordinates are positive.

Diffstat:
M
src/s3d_scene_view_closest_point.c
 | 
6
+++++-

1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/src/s3d_scene_view_closest_point.c b/src/s3d_scene_view_closest_point.c
@@ -144,9 +144,13 @@ closest_point_triangle
   /* Save the uv barycentric coordinates */
   uv[0] = 1.f - v - w;
   uv[1] = v;
-
   ASSERT(eq_epsf(uv[0] + uv[1] + w, 1.f, 1.e-4f));
 
+  if(uv[0] < 0.f) { /* Handle precision issues */
+    if(uv[1] > w) uv[1] += uv[0];
+    uv[0] = 0;
+  }
+
   /* Use the barycentric coordinates to compute the world space position of the
    * closest point onto the triangle */
   closest_pt[0] = a[0] + v*ab[0] + w*ac[0];