neatogen: remove upfront allocation of trigraph edges

Following on from fc465488e1e62fe5ef879b379a07ef272431f400, this removes
assumptions about how many total edges will be generated by this algorithm. New
edges are now allocated on demand when appending.

diff --git a/lib/neatogen/multispline.c b/lib/neatogen/multispline.c
index eec809fea8e7f9c341128c97963c85ae5d3f17f0..0da8a3eb4aec5268c0e4b9d88bece74d7bd2670c 100644 (file)
--- a/lib/neatogen/multispline.c
+++ b/lib/neatogen/multispline.c
@@ -528,6 +528,8 @@ static ipair sharedEdge(int *p, int *q)
  * segment seg.
  */
 static void addTriEdge(tgraph *g, int t, int h, ipair seg) {
+    g->edges = gv_recalloc(g->edges, g->nedges, g->nedges + 1,
+                           sizeof(g->edges[0]));
     tedge *ep = g->edges + g->nedges;
     tnode *tp = g->nodes + t;
     tnode *hp = g->nodes + h;
@@ -579,10 +581,7 @@ static tgraph *mkTriGraph(surface_t * sf, int maxv, pointf * pts)
     g->nnodes = sf->nfaces + 2;
     g->nodes = N_GNEW(g->nnodes, tnode);
 
-    /* allow 1 possible extra edge per triangle, plus 
-     * obstacles can have at most maxv triangles touching 
-     */
-    g->edges = N_GNEW(ne/2 + 2 * maxv, tedge);
+    g->edges = NULL;
     g->nedges = 0;
 
     for (i = 0; i < sf->nfaces; i++) {