merge

Merge remote branch 'upstream/visitor' into visitortests

Conflicts:
	src/export.cc
	src/openscad.cc
	src/polyset.cc
	src/transform.cc
	tests/CMakeLists.txt
	tests/FindGLEW.cmake
	tests/csgtermtest.cc

1 files changed, 28 insertions, 2 deletions

diff --git a/testdata/scad/features/difference-tests.scad b/testdata/scad/features/difference-tests.scad
index f945246..4d82676 100644
--- a/testdata/scad/features/difference-tests.scad
+++ b/testdata/scad/features/difference-tests.scad
@@ -1,4 +1,30 @@
+// Empty
+difference();
+// No children
+difference() { }
+
 difference() {
-  sphere(3);
-  cube([3,3,8], center=true);
+  cube([10,10,10], center=true);
+  cylinder(r=4, h=20, center=true);
+}
+
+translate([12,0,0]) difference() {
+  cube([10,10,10], center=true);
+  cylinder(r=4, h=10, center=true);
+}
+
+translate([0,12,0]) difference() {
+  cube([10,10,10], center=true);
+  cylinder(r=4, h=11, center=true);
+  rotate([0,90,0]) cylinder(r=4, h=11, center=true);
+}
+
+translate([12,12,0]) difference() {
+  cube([10,10,10], center=true);
+  translate([0,0,7]) cylinder(r=4, h=4, center=true);
+}
+
+translate([24,0,0]) difference() {
+  cube([10,10,10], center=true);
+  translate([0,0,6.99]) cylinder(r=4, h=4, center=true);
 }