stardis-solver

commit 7c1d8ac42ab0c9627285dc8d561d08c444aac483
parent 50aa5093f2c95dec2d743439527d0efdbabd3fd3
Author: Vincent Forest <vincent.forest@meso-star.com>
Date:   Mon,  6 May 2019 16:12:41 +0200

Handle a numerical issue in scene_get_medium_closed_boundaries

Diffstat:
M
src/sdis_scene_Xd.h
 | 
18
+++++++++++++++++-

1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/src/sdis_scene_Xd.h b/src/sdis_scene_Xd.h
@@ -1072,18 +1072,34 @@ XD(scene_get_medium_in_closed_boundaries)
 {
   struct sdis_medium* medium = NULL;
   float P[DIM];
+  float frame[DIM*DIM];
+  float N[DIM];
   float dirs[6][3] = {{1,0,0},{-1,0,0},{0,1,0},{0,-1,0},{0,0,1},{0,0,-1}};
   int idir;
   res_T res = RES_OK;
   ASSERT(scn && pos);
 
+#if DIM == 2
+  /* TODO build the frame */
+  (void)frame;
+#else
+  /* Build a frame that will be used to rotate the main axis by PI/4 around
+   * each axis. This can avoid numerical issues when geometry is discretized
+   * along the main axis */
+  N[0] = N[1] = N[2] = (float)(1.0 / sqrt(3.0));
+  f33_basis(frame, N);
+#endif
+
   fX_set_dX(P, pos);
   FOR_EACH(idir, 0, 2*DIM) {
     struct sXd(hit) hit;
     const float range[2] = {0.f, FLT_MAX};
-    float N[DIM];
     float cos_N_dir;
 
+#if DIM == 3
+    f33_mulf3(dirs[idir], frame, dirs[idir]);
+#endif
+
     /* Trace a ray from the random walk vertex toward the retrieved primitive
      * position */
     SXD(scene_view_trace_ray(scn->sXd(view), P, dirs[idir], range, NULL, &hit));