ctrans.hpp.diff

diff --git a/include/mapnik/ctrans.hpp b/include/mapnik/ctrans.hpp
index f02ab48..2093e3d 100644
--- a/include/mapnik/ctrans.hpp
+++ b/include/mapnik/ctrans.hpp
@@ -83,12 +83,21 @@ struct MAPNIK_DECL coord_transform
 
     unsigned vertex(double *x, double *y) const
     {
-        unsigned command = geom_.vertex(x, y);
-        if ( command != SEG_END)
+        unsigned command = SEG_MOVETO;
+        bool ok = false;
+        bool skipped_points = false;
+        double z = 0;
+        while (!ok && command != SEG_END)
         {
-            double z = 0;
-            if (!prj_trans_->backward(*x, *y, z))
-                return SEG_END;
+            command = geom_.vertex(x, y);
+            ok = prj_trans_->backward(*x, *y, z);
+            if (!ok) {
+                skipped_points = true;
+            }
+        }
+        if (skipped_points && (command == SEG_LINETO))
+        {
+            command = SEG_MOVETO;
         }
         t_->forward(x, y);
         return command;