Factor in SOutlineList::FillOutlineTags.

src/glhelper.cpp

@@ -481,9 +481,8 @@ void ssglDrawOutlines(SOutlineList *sol, Vector projDir, hStyle hs)
     ssglLineWidth((float)lineWidth);
     ssglColorRGB(Style::Color(hs));
 
-    sol->FillOutlineTags(projDir);
     for(SOutline *so = sol->l.First(); so; so = sol->l.NextAfter(so)) {
-        if(!so->tag) continue;
+        if(!so->IsVisible(projDir)) continue;
         ssglStippledLine(so->a, so->b, lineWidth, stippleType, stippleScale,
                          /*maybeFat=*/true);
     }

src/mesh.cpp

@@ -1047,6 +1047,10 @@ void SKdNode::MakeOutlinesInto(SOutlineList *sol) const
     }
 }
 
+bool SOutline::IsVisible(Vector projDir) const {
+    return (nl.Dot(projDir) > 0.0) != (nr.Dot(projDir) > 0.0);
+}
+
 void SOutlineList::Clear() {
     l.Clear();
 }
@@ -1060,12 +1064,6 @@ void SOutlineList::AddEdge(Vector a, Vector b, Vector nl, Vector nr) {
     l.Add(&so);
 }
 
-void SOutlineList::FillOutlineTags(Vector projDir) {
-    for(SOutline *so = l.First(); so; so = l.NextAfter(so)) {
-        so->tag = ((so->nl.Dot(projDir) > 0.0) != (so->nr.Dot(projDir) > 0.0));
-    }
-}
-
 void SOutlineList::MakeFromCopyOf(SOutlineList *sol) {
     for(SOutline *so = sol->l.First(); so; so = sol->l.NextAfter(so)) {
         l.Add(so);

src/polygon.h

@@ -274,6 +274,8 @@ class SOutline {
 public:
     int    tag;
     Vector a, b, nl, nr;
+
+    bool IsVisible(Vector projDir) const;
 };
 
 class SOutlineList {
@@ -284,8 +286,6 @@ public:
     void AddEdge(Vector a, Vector b, Vector nl, Vector nr);
 
     void MakeFromCopyOf(SOutlineList *ol);
-
-    void FillOutlineTags(Vector projDir);
 };
 
 class SKdNode {