diff --git a/tests/compare-bitmaps.sh b/tests/compare-bitmaps.sh
new file mode 100755
index 00000000..590d0b57
--- /dev/null
+++ b/tests/compare-bitmaps.sh
@@ -0,0 +1,31 @@
+#!/bin/sh
+
+
+while getopts 'v' c
+do
+  case $c in
+    v) set -x ;;
+  esac
+done
+
+shift $(($OPTIND - 1))
+
+# FIXME: Sometimes, compare fails when comparing very small images (e.g. 40 x 10 pixels).
+# It's unknown why this happens..
+pixelerror=`compare -fuzz 10% -metric AE $1 $2 null: 2>&1`
+if [ $? -ne 0 ]; then
+    echo "General error: Ouch"
+    exit 1 # Compare failed to read image
+else
+  # Check if $pixelerror contains an integer (it sometimes outputs things like '0 @ 0,0')
+  if [ $pixelerror -eq $pixelerror 2> /dev/null ]; then
+    if [ $pixelerror == 0 ]; then 
+      exit 0
+    fi
+    echo "Pixel error: $pixelerror"
+  else
+    echo "Pixel error: Err"
+  fi
+  exit 1
+fi
+exit 0
diff --git a/tests/regression/opencsgtest/cube-expected.png b/tests/regression/opencsgtest/cube-expected.png
new file mode 100644
index 00000000..2de1a5f9
Binary files /dev/null and b/tests/regression/opencsgtest/cube-expected.png differ
diff --git a/tests/regression/opencsgtest/cylinder-expected.png b/tests/regression/opencsgtest/cylinder-expected.png
new file mode 100644
index 00000000..aea350c8
Binary files /dev/null and b/tests/regression/opencsgtest/cylinder-expected.png differ
diff --git a/tests/regression/opencsgtest/example001-expected.png b/tests/regression/opencsgtest/example001-expected.png
new file mode 100644
index 00000000..48509b28
Binary files /dev/null and b/tests/regression/opencsgtest/example001-expected.png differ
diff --git a/tests/regression/opencsgtest/sphere-expected.png b/tests/regression/opencsgtest/sphere-expected.png
new file mode 100644
index 00000000..63636d44
Binary files /dev/null and b/tests/regression/opencsgtest/sphere-expected.png differ
diff --git a/tests/test_cmdline_tool.py b/tests/test_cmdline_tool.py
index 8fe48905..b8a0d071 100755
--- a/tests/test_cmdline_tool.py
+++ b/tests/test_cmdline_tool.py
@@ -32,7 +32,7 @@ def initialize_environment():
 def init_expected_filename(testname, cmd):
     global expecteddir, expectedfilename
     expecteddir = os.path.join(options.regressiondir, os.path.split(cmd)[1])
-    expectedfilename = os.path.join(expecteddir, testname + "-expected" + options.suffix)
+    expectedfilename = os.path.join(expecteddir, testname + "-expected." + options.suffix)
 
 def verify_test(testname, cmd):
     global expectedfilename
@@ -54,18 +54,28 @@ def get_normalized_text(filename):
 def compare_text(expected, actual):
     return get_normalized_text(expected) == get_normalized_text(actual)
 
+def compare_default(resultfilename):
+    if not compare_text(expectedfilename, resultfilename): 
+        execute_and_redirect("diff", [expectedfilename, resultfilename], sys.stderr)
+        return False
+    return True
+
+def compare_png(resultfilename):
+    if execute_and_redirect("diff", [expectedfilename, resultfilename], sys.stderr) != 0:
+        return False
+    return True
+
 def compare_with_expected(resultfilename):
     if not options.generate:
-        if not compare_text(expectedfilename, resultfilename): 
-            execute_and_redirect("diff", [expectedfilename, resultfilename], sys.stderr)
-            return False
+        if "compare_" + options.suffix in globals(): return globals()["compare_" + options.suffix](resultfilename)
+        else: return compare_default(resultfilename)
     return True
 
 def run_test(testname, cmd, args):
     cmdname = os.path.split(options.cmd)[1]
 
     outputdir = os.path.join(os.getcwd(), cmdname + "-output")
-    actualfilename = os.path.join(outputdir, testname + "-actual" + options.suffix)
+    actualfilename = os.path.join(outputdir, testname + "-actual." + options.suffix)
 
     if options.generate: 
         if not os.path.exists(expecteddir): os.makedirs(expecteddir)
@@ -116,13 +126,12 @@ if __name__ == '__main__':
     options = Options()
     options.regressiondir = os.path.join(os.path.split(sys.argv[0])[0], "regression")
     options.generate = False
-    options.suffix = ".txt"
+    options.suffix = "txt"
     for o, a in opts:
         if o in ("-g", "--generate"): options.generate = True
         elif o in ("-s", "--suffix"):
-            if a[0] == '.': options.suffix = ""
-            else: options.suffix = "."
-            options.suffix += a
+            if a[0] == '.': options.suffix = a[1:]
+            else: options.suffix = a
         elif o in ("-t", "--test"):
             options.testname = a