From: Barak Itkin <lightningismyname@gmail.com>
Date: Sat, 19 May 2012 10:21:39 +0000 (+0300)
Subject: Fix a bug in delaunay-terminator.c (comparing removed triangles)
X-Git-Tag: p2tc-0.1.0~66
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=87f867ded88f5bc8aac6e7c205844589bb9b202e;p=poly2tri-c

Fix a bug in delaunay-terminator.c (comparing removed triangles)
Also, add debugging calls in several parts of the code
---

diff --git a/refine/delaunay-terminator.c b/refine/delaunay-terminator.c
index 41bf550..bc7ef54 100644
--- a/refine/delaunay-terminator.c
+++ b/refine/delaunay-terminator.c
@@ -115,8 +115,21 @@ ChooseSplitVertex(P2trEdge *e, P2trVector2 *dst);
 static inline gint
 triangle_quality_compare (P2trTriangle *t1, P2trTriangle *t2)
 {
-  gdouble a1 = p2tr_triangle_smallest_non_constrained_angle (t1);
-  gdouble a2 = p2tr_triangle_smallest_non_constrained_angle (t2);
+  gdouble a1, a2;
+  gboolean r1, r2;
+
+  r1 = p2tr_triangle_is_removed (t1);
+  r2 = p2tr_triangle_is_removed (t2);
+
+  /* TODO: untill we make sure that removed triangles will get out
+   * of Qt, we will make the comparision treat removed triangles as
+   * triangles with "less" quality (meaning they are "smaller")
+   */
+  if (r1 || r2)
+    return (r1) ? -1 : (r2 ? 1 : 0);
+
+  a1 = p2tr_triangle_smallest_non_constrained_angle (t1);
+  a2 = p2tr_triangle_smallest_non_constrained_angle (t2);
   
   return (a1 < a2) ? -1 : ((a1 == a2) ? 0 : 1);
 }
@@ -202,22 +215,27 @@ p2tr_dt_refine (P2trDelaunayTerminator *self,
   P2trHashSetIter hs_iter;
   P2trEdge *s;
   P2trTriangle *t;
-  gint steps;
+  gint steps = 0;
   
+  p2tr_cdt_validate_cdt(self->mesh);
+
+  if (steps++ >= max_steps)
+    return;
+
   p2tr_hash_set_iter_init (&hs_iter, self->mesh->mesh->edges);
     while (p2tr_hash_set_iter_next (&hs_iter, (gpointer*)&s))
     if (s->constrained && p2tr_cdt_is_encroached (s))
       p2tr_dt_enqueue_segment (self, s);
 
   SplitEncroachedSubsegments (self, 0, p2tr_dt_false_too_big);
+  p2tr_cdt_validate_cdt(self->mesh);
 
   p2tr_hash_set_iter_init (&hs_iter, self->mesh->mesh->triangles);
   while (p2tr_hash_set_iter_next (&hs_iter, (gpointer*)&t))
     if (p2tr_triangle_smallest_non_constrained_angle (t) < self->theta)
       p2tr_dt_enqueue_tri (self, t);
 
-  steps = 0;
-  while (! p2tr_dt_tri_queue_is_empty (self) && steps < max_steps)
+  while (! p2tr_dt_tri_queue_is_empty (self) && steps++ < max_steps)
     {
       t = p2tr_dt_dequeue_tri (self);
 
@@ -227,7 +245,8 @@ p2tr_dt_refine (P2trDelaunayTerminator *self,
           P2trVector2 *c;
           P2trTriangle *triContaining_c_NOREF;
           P2trHashSet *E;
-          
+
+          p2tr_cdt_validate_cdt (self->mesh);
           p2tr_triangle_get_circum_circle (t, &tCircum);
           c = &tCircum.center;
 
diff --git a/refine/triangle.c b/refine/triangle.c
index b46f41d..90a18a7 100644
--- a/refine/triangle.c
+++ b/refine/triangle.c
@@ -9,15 +9,18 @@
 #include "triangle.h"
 #include "mesh.h"
 
-P2trTriangle*
-p2tr_triangle_new (P2trEdge *AB,
-                   P2trEdge *BC,
-                   P2trEdge *CA)
+void
+p2tr_validate_edges_can_form_tri (P2trEdge *AB,
+                                  P2trEdge *BC,
+                                  P2trEdge *CA)
 {
-  gint i;
-  P2trTriangle *self = g_slice_new (P2trTriangle);
+  if (AB != AB->mirror->mirror ||
+      BC != BC->mirror->mirror ||
+      CA != CA->mirror->mirror)
+    {
+      p2tr_exception_programmatic ("Bad edge mirroring!");
+    }
 
-#ifndef P2TC_NO_LOGIC_CHECKS
   if (AB->end != P2TR_EDGE_START(BC)
       || BC->end != P2TR_EDGE_START(CA)
       || CA->end != P2TR_EDGE_START(AB))
@@ -29,6 +32,18 @@ p2tr_triangle_new (P2trEdge *AB,
     {
       p2tr_exception_programmatic ("Repeated edge in a triangle!");
     }
+}
+
+P2trTriangle*
+p2tr_triangle_new (P2trEdge *AB,
+                   P2trEdge *BC,
+                   P2trEdge *CA)
+{
+  gint i;
+  P2trTriangle *self = g_slice_new (P2trTriangle);
+
+#ifndef P2TC_NO_LOGIC_CHECKS
+  p2tr_validate_edges_can_form_tri (AB, BC, CA);
 #endif
 
   switch (p2tr_math_orient2d(&CA->end->c, &AB->end->c, &BC->end->c))
@@ -49,7 +64,9 @@ p2tr_triangle_new (P2trEdge *AB,
         p2tr_exception_geometric ("Can't make a triangle of linear points!");
     }
 
-#ifdef P2TC_DEBUG_CHECKS
+#ifndef P2TC_NO_LOGIC_CHECKS
+  p2tr_validate_edges_can_form_tri (self->edges[0], self->edges[1], self->edges[2]);
+
   if (p2tr_math_orient2d (&P2TR_TRIANGLE_GET_POINT(self,0)->c,
                           &P2TR_TRIANGLE_GET_POINT(self,1)->c,
                           &P2TR_TRIANGLE_GET_POINT(self,2)->c) != P2TR_ORIENTATION_CW)
@@ -60,7 +77,7 @@ p2tr_triangle_new (P2trEdge *AB,
 
   for (i = 0; i < 3; i++)
     {
-#ifdef P2TC_DEBUG_CHECKS
+#ifndef P2TC_NO_LOGIC_CHECKS
       if (self->edges[i]->tri != NULL)
         p2tr_exception_programmatic ("This edge is already in use by "
             "another triangle!");