Merge branch 'master' into issue527

doc/testing.txt

@@ -3,10 +3,8 @@ Running regression tests:
 
 Prerequisites: cmake, python, ImageMagick 6.5.9.3 or newer
 
-First, get a working qmake GUI build of the main openscad binary. It is 
-used by the tests. Next, get MCAD installed by using 
-
-  'git submodule update --init'
+First, get a working qmake GUI build of the main openscad binary and install MCAD.
+See the main README.
 
 A) Building test environment
 
@@ -38,10 +36,11 @@ $ ctest -C <configs>  Adds extended tests belonging to configs.
                       Default  - Run default tests
                       Heavy    - Run more time consuming tests (> ~10 seconds)
                       Examples - test all examples
+                      Bugs     - test known bugs (tests will fail)
                       All      - test everything
 
-Adding a new regression test:
-------------------------------
+Adding a new test:
+------------------
 
 1) create a test file at an appropriate location under testdata/
 2) if the test is non-obvious, create a human readable description as comments in the test (or in another file in the same directory in case the file isn't human readable)

testdata/scad/features/minkowski2-tests.scad

@@ -32,3 +32,10 @@ translate([25,0,0]) roundedBox2dSimple();
 
 // One child
 translate([0,-20,0]) minkowski() { square(10); }
+
+// >2 children
+translate([-20,-20,0]) minkowski() {
+    square(10);
+    square(2, center=true);
+    circle(1);
+}

tests/regression/dumptest/minkowski2-tests-expected.csg

@@ -34,4 +34,11 @@ group() {
 			square(size = [10, 10], center = false);
 		}
 	}
+	multmatrix([[1, 0, 0, -20], [0, 1, 0, -20], [0, 0, 1, 0], [0, 0, 0, 1]]) {
+		minkowski(convexity = 0) {
+			square(size = [10, 10], center = false);
+			square(size = [2, 2], center = true);
+			circle($fn = 0, $fa = 12, $fs = 2, r = 1);
+		}
+	}
 }