From 19fbae5b6610dd47eda49f25d7af0c9ea069794b Mon Sep 17 00:00:00 2001
From: Jonathan Westhues <jwesthues@cq.cx>
Date: Wed, 10 Jun 2009 00:26:09 -0800
Subject: [PATCH] Oops, don't let the coincident surface merging stuff try to
 merge empty (no trims) surfaces. It will generate a screwy bounding box,
 which will make things break numerically later.

[git-p4: depot-paths = "//depot/solvespace/": change = 1979]
---
 srf/merge.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/srf/merge.cpp b/srf/merge.cpp
index 52551298..e5816859 100644
--- a/srf/merge.cpp
+++ b/srf/merge.cpp
@@ -13,6 +13,9 @@ void SShell::MergeCoincidentSurfaces(void) {
     for(i = 0; i < surface.n; i++) {
         si = &(surface.elem[i]);
         if(si->tag) continue;
+        // Let someone else clean up the empty surfaces; we can certainly merge
+        // them, but we don't know how to calculate a reasonable bounding box.
+        if(si->trim.n == 0) continue;
 
         SEdgeList sel;
         ZERO(&sel);