star-enclosures-3d

commit 2c0a29b18cfb52cfa5b461e474e321b8669402fd
parent f2313c345c26c603c72e87a85369ec360f1aaf4b
Author: Christophe Coustet <christophe.coustet@meso-star.com>
Date:   Fri, 12 Jun 2020 14:17:10 +0200

BugFix: could enter an endless loop with some invalid models

Diffstat:
M
src/senc3d_scene_analyze.c
 | 
30
++++++++++++++++++++++++++++++

1 file changed, 30 insertions(+), 0 deletions(-)
diff --git a/src/senc3d_scene_analyze.c b/src/senc3d_scene_analyze.c
@@ -57,6 +57,7 @@ struct filter_ctx {
   struct senc3d_scene* scn;
   component_id_t origin_component;
   struct darray_triangle_comp* triangles_comp;
+  struct darray_ptr_component_descriptor* components;
   /* Result of hit */
   component_id_t hit_component;
 };
@@ -175,6 +176,34 @@ self_hit_filter
     ? SENC3D_BACK : SENC3D_FRONT;
 
   filter_ctx->hit_component = hit_trg_comp->component[hit_side];
+
+  if(hit->distance == 0) {
+    /* To avoid create loops, allow dist=0 only if the hit component has
+     * a higher max_z than the origin component */
+    const struct cc_descriptor** descriptors
+      = darray_ptr_component_descriptor_cdata_get(filter_ctx->components);
+    const struct cc_descriptor* origin_desc;
+    const struct cc_descriptor* hit_desc;
+    const union double3* positions
+      = darray_position_cdata_get(&filter_ctx->scn->vertices);
+    ASSERT(filter_ctx->origin_component
+      < darray_ptr_component_descriptor_size_get(filter_ctx->components));
+    ASSERT(filter_ctx->hit_component
+      < darray_ptr_component_descriptor_size_get(filter_ctx->components));
+    origin_desc = descriptors[filter_ctx->origin_component];
+    hit_desc = descriptors[filter_ctx->hit_component];
+    ASSERT(origin_desc->max_z_vrtx_id
+      < darray_position_size_get(&filter_ctx->scn->vertices));
+    ASSERT(hit_desc->max_z_vrtx_id
+      < darray_position_size_get(&filter_ctx->scn->vertices));
+    ASSERT(positions[origin_desc->max_z_vrtx_id].pos.z
+      <= positions[origin_desc->max_z_vrtx_id].pos.z);
+    if(positions[origin_desc->max_z_vrtx_id].pos.z
+      == positions[origin_desc->max_z_vrtx_id].pos.z)
+    {
+      return 1;
+    }
+  }
   return 0; /* Keep */
 }
 
@@ -637,6 +666,7 @@ group_connex_components
   positions = darray_position_cdata_get(&scn->vertices);
   filter_ctx.scn = scn;
   filter_ctx.triangles_comp = triangles_comp;
+  filter_ctx.components = connex_components;
   *res = s3d_scene_view_get_aabb(s3d_view, lower, upper);
   if(*res != RES_OK) return;
   /* Cast rays to find links between connex components */