1 files changed, 25 insertions, 0 deletions
diff --git a/testdata/scad/bugs/issue591.scad b/testdata/scad/bugs/issue591.scad
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+++ b/testdata/scad/bugs/issue591.scad
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+// Creates the same "non-manifold" object (sharing one edge) using two techniques:
+// o linear_extrude of two 2D objects
+// o union of two linear_extrudes
+//
+// Subsequently cuts away the non-manifold part:
+// -> the first technique fails, the second one succeeds
+//
+module cutoff() {
+    difference() {
+        children();
+        translate([0,0,2.5]) cube(2, center=true);
+    }
+}
+
+cutoff() {
+    linear_extrude(height=3, scale=[0,1], convexity=2) {
+        translate([1,0,0]) square(1,true);
+        translate([-1,0,0]) square(1,true);
+    }
+}
+
+translate([0,2,0]) cutoff() {
+    linear_extrude(height=3, scale=[0,1]) translate([1,0,0]) square(1,true);
+    linear_extrude(height=3, scale=[0,1]) translate([-1,0,0]) square(1,true);
+}