diff --git a/tests/regression/cgalpngtest/example001-expected.png b/tests/regression/cgalpngtest/example001-expected.png
new file mode 100644
index 00000000..12b3deaa
Binary files /dev/null and b/tests/regression/cgalpngtest/example001-expected.png differ
diff --git a/tests/regression/cgalpngtest/example002-expected.png b/tests/regression/cgalpngtest/example002-expected.png
new file mode 100644
index 00000000..491477da
Binary files /dev/null and b/tests/regression/cgalpngtest/example002-expected.png differ
diff --git a/tests/regression/cgalpngtest/example003-expected.png b/tests/regression/cgalpngtest/example003-expected.png
new file mode 100644
index 00000000..429b64b6
Binary files /dev/null and b/tests/regression/cgalpngtest/example003-expected.png differ
diff --git a/tests/regression/cgalpngtest/example004-expected.png b/tests/regression/cgalpngtest/example004-expected.png
new file mode 100644
index 00000000..b0a91fd8
Binary files /dev/null and b/tests/regression/cgalpngtest/example004-expected.png differ
diff --git a/tests/regression/cgalpngtest/example005-expected.png b/tests/regression/cgalpngtest/example005-expected.png
new file mode 100644
index 00000000..8727800b
Binary files /dev/null and b/tests/regression/cgalpngtest/example005-expected.png differ
diff --git a/tests/regression/cgalpngtest/example006-expected.png b/tests/regression/cgalpngtest/example006-expected.png
new file mode 100644
index 00000000..c2fd5c1e
Binary files /dev/null and b/tests/regression/cgalpngtest/example006-expected.png differ
diff --git a/tests/regression/cgalpngtest/example007-expected.png b/tests/regression/cgalpngtest/example007-expected.png
new file mode 100644
index 00000000..0ec829fb
Binary files /dev/null and b/tests/regression/cgalpngtest/example007-expected.png differ
diff --git a/tests/regression/cgalpngtest/example008-expected.png b/tests/regression/cgalpngtest/example008-expected.png
new file mode 100644
index 00000000..54cd35d6
Binary files /dev/null and b/tests/regression/cgalpngtest/example008-expected.png differ
diff --git a/tests/regression/cgalpngtest/example009-expected.png b/tests/regression/cgalpngtest/example009-expected.png
new file mode 100644
index 00000000..bbdc1921
Binary files /dev/null and b/tests/regression/cgalpngtest/example009-expected.png differ
diff --git a/tests/regression/cgalpngtest/example010-expected.png b/tests/regression/cgalpngtest/example010-expected.png
new file mode 100644
index 00000000..f611b128
Binary files /dev/null and b/tests/regression/cgalpngtest/example010-expected.png differ
diff --git a/tests/regression/cgalpngtest/example011-expected.png b/tests/regression/cgalpngtest/example011-expected.png
new file mode 100644
index 00000000..88c8299d
Binary files /dev/null and b/tests/regression/cgalpngtest/example011-expected.png differ
diff --git a/tests/regression/cgalpngtest/example012-expected.png b/tests/regression/cgalpngtest/example012-expected.png
new file mode 100644
index 00000000..8065e9c4
Binary files /dev/null and b/tests/regression/cgalpngtest/example012-expected.png differ
diff --git a/tests/regression/cgalpngtest/example013-expected.png b/tests/regression/cgalpngtest/example013-expected.png
new file mode 100644
index 00000000..331fa170
Binary files /dev/null and b/tests/regression/cgalpngtest/example013-expected.png differ
diff --git a/tests/regression/cgalpngtest/example014-expected.png b/tests/regression/cgalpngtest/example014-expected.png
new file mode 100644
index 00000000..73453a25
Binary files /dev/null and b/tests/regression/cgalpngtest/example014-expected.png differ
diff --git a/tests/regression/cgalpngtest/example015-expected.png b/tests/regression/cgalpngtest/example015-expected.png
new file mode 100644
index 00000000..98d0e788
Binary files /dev/null and b/tests/regression/cgalpngtest/example015-expected.png differ
diff --git a/tests/regression/cgalpngtest/example016-expected.png b/tests/regression/cgalpngtest/example016-expected.png
new file mode 100644
index 00000000..70bd10d7
Binary files /dev/null and b/tests/regression/cgalpngtest/example016-expected.png differ
diff --git a/tests/regression/cgalpngtest/example017-expected.png b/tests/regression/cgalpngtest/example017-expected.png
new file mode 100644
index 00000000..05f429b5
Binary files /dev/null and b/tests/regression/cgalpngtest/example017-expected.png differ
diff --git a/tests/regression/cgalpngtest/example018-expected.png b/tests/regression/cgalpngtest/example018-expected.png
new file mode 100644
index 00000000..5ea05af4
Binary files /dev/null and b/tests/regression/cgalpngtest/example018-expected.png differ
diff --git a/tests/regression/cgalpngtest/example019-expected.png b/tests/regression/cgalpngtest/example019-expected.png
new file mode 100644
index 00000000..42a356a4
Binary files /dev/null and b/tests/regression/cgalpngtest/example019-expected.png differ
diff --git a/tests/regression/cgalpngtest/example020-expected.png b/tests/regression/cgalpngtest/example020-expected.png
new file mode 100644
index 00000000..e6afb94d
Binary files /dev/null and b/tests/regression/cgalpngtest/example020-expected.png differ
diff --git a/tests/regression/cgalpngtest/example021-expected.png b/tests/regression/cgalpngtest/example021-expected.png
new file mode 100644
index 00000000..d657b0d3
Binary files /dev/null and b/tests/regression/cgalpngtest/example021-expected.png differ
diff --git a/tests/regression/cgalpngtest/example022-expected.png b/tests/regression/cgalpngtest/example022-expected.png
new file mode 100644
index 00000000..b8b8fbd2
Binary files /dev/null and b/tests/regression/cgalpngtest/example022-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..ff2da6bc
Binary files /dev/null and b/tests/regression/opencsgtest/example001-expected.png differ
diff --git a/tests/regression/opencsgtest/example002-expected.png b/tests/regression/opencsgtest/example002-expected.png
new file mode 100644
index 00000000..554dc133
Binary files /dev/null and b/tests/regression/opencsgtest/example002-expected.png differ
diff --git a/tests/regression/opencsgtest/example003-expected.png b/tests/regression/opencsgtest/example003-expected.png
new file mode 100644
index 00000000..1faa4a6d
Binary files /dev/null and b/tests/regression/opencsgtest/example003-expected.png differ
diff --git a/tests/regression/opencsgtest/example004-expected.png b/tests/regression/opencsgtest/example004-expected.png
new file mode 100644
index 00000000..beb549cc
Binary files /dev/null and b/tests/regression/opencsgtest/example004-expected.png differ
diff --git a/tests/regression/opencsgtest/example005-expected.png b/tests/regression/opencsgtest/example005-expected.png
new file mode 100644
index 00000000..0bb2fefc
Binary files /dev/null and b/tests/regression/opencsgtest/example005-expected.png differ
diff --git a/tests/regression/opencsgtest/example006-expected.png b/tests/regression/opencsgtest/example006-expected.png
new file mode 100644
index 00000000..ff0fe35d
Binary files /dev/null and b/tests/regression/opencsgtest/example006-expected.png differ
diff --git a/tests/regression/opencsgtest/example007-expected.png b/tests/regression/opencsgtest/example007-expected.png
new file mode 100644
index 00000000..b212b123
Binary files /dev/null and b/tests/regression/opencsgtest/example007-expected.png differ
diff --git a/tests/regression/opencsgtest/example008-expected.png b/tests/regression/opencsgtest/example008-expected.png
new file mode 100644
index 00000000..0e4241f0
Binary files /dev/null and b/tests/regression/opencsgtest/example008-expected.png differ
diff --git a/tests/regression/opencsgtest/example009-expected.png b/tests/regression/opencsgtest/example009-expected.png
new file mode 100644
index 00000000..541410d8
Binary files /dev/null and b/tests/regression/opencsgtest/example009-expected.png differ
diff --git a/tests/regression/opencsgtest/example010-expected.png b/tests/regression/opencsgtest/example010-expected.png
new file mode 100644
index 00000000..3a4ba273
Binary files /dev/null and b/tests/regression/opencsgtest/example010-expected.png differ
diff --git a/tests/regression/opencsgtest/example011-expected.png b/tests/regression/opencsgtest/example011-expected.png
new file mode 100644
index 00000000..13164c3e
Binary files /dev/null and b/tests/regression/opencsgtest/example011-expected.png differ
diff --git a/tests/regression/opencsgtest/example012-expected.png b/tests/regression/opencsgtest/example012-expected.png
new file mode 100644
index 00000000..c705bc77
Binary files /dev/null and b/tests/regression/opencsgtest/example012-expected.png differ
diff --git a/tests/regression/opencsgtest/example013-expected.png b/tests/regression/opencsgtest/example013-expected.png
new file mode 100644
index 00000000..5917382e
Binary files /dev/null and b/tests/regression/opencsgtest/example013-expected.png differ
diff --git a/tests/regression/opencsgtest/example014-expected.png b/tests/regression/opencsgtest/example014-expected.png
new file mode 100644
index 00000000..7f39f612
Binary files /dev/null and b/tests/regression/opencsgtest/example014-expected.png differ
diff --git a/tests/regression/opencsgtest/example015-expected.png b/tests/regression/opencsgtest/example015-expected.png
new file mode 100644
index 00000000..1a1c8697
Binary files /dev/null and b/tests/regression/opencsgtest/example015-expected.png differ
diff --git a/tests/regression/opencsgtest/example016-expected.png b/tests/regression/opencsgtest/example016-expected.png
new file mode 100644
index 00000000..1288ff68
Binary files /dev/null and b/tests/regression/opencsgtest/example016-expected.png differ
diff --git a/tests/regression/opencsgtest/example017-expected.png b/tests/regression/opencsgtest/example017-expected.png
new file mode 100644
index 00000000..b0b2f8a3
Binary files /dev/null and b/tests/regression/opencsgtest/example017-expected.png differ
diff --git a/tests/regression/opencsgtest/example018-expected.png b/tests/regression/opencsgtest/example018-expected.png
new file mode 100644
index 00000000..033a1365
Binary files /dev/null and b/tests/regression/opencsgtest/example018-expected.png differ
diff --git a/tests/regression/opencsgtest/example019-expected.png b/tests/regression/opencsgtest/example019-expected.png
new file mode 100644
index 00000000..306c0fb7
Binary files /dev/null and b/tests/regression/opencsgtest/example019-expected.png differ
diff --git a/tests/regression/opencsgtest/example020-expected.png b/tests/regression/opencsgtest/example020-expected.png
new file mode 100644
index 00000000..4e8c3c41
Binary files /dev/null and b/tests/regression/opencsgtest/example020-expected.png differ
diff --git a/tests/regression/opencsgtest/example021-expected.png b/tests/regression/opencsgtest/example021-expected.png
new file mode 100644
index 00000000..675e57b3
Binary files /dev/null and b/tests/regression/opencsgtest/example021-expected.png differ
diff --git a/tests/regression/opencsgtest/example022-expected.png b/tests/regression/opencsgtest/example022-expected.png
new file mode 100644
index 00000000..66738e0b
Binary files /dev/null and b/tests/regression/opencsgtest/example022-expected.png differ
diff --git a/tests/regression/throwntogethertest/example001-expected.png b/tests/regression/throwntogethertest/example001-expected.png
new file mode 100644
index 00000000..a0ea588e
Binary files /dev/null and b/tests/regression/throwntogethertest/example001-expected.png differ
diff --git a/tests/regression/throwntogethertest/example002-expected.png b/tests/regression/throwntogethertest/example002-expected.png
new file mode 100644
index 00000000..27e3c4ec
Binary files /dev/null and b/tests/regression/throwntogethertest/example002-expected.png differ
diff --git a/tests/regression/throwntogethertest/example003-expected.png b/tests/regression/throwntogethertest/example003-expected.png
new file mode 100644
index 00000000..f27d17ce
Binary files /dev/null and b/tests/regression/throwntogethertest/example003-expected.png differ
diff --git a/tests/regression/throwntogethertest/example004-expected.png b/tests/regression/throwntogethertest/example004-expected.png
new file mode 100644
index 00000000..0d2f1baf
Binary files /dev/null and b/tests/regression/throwntogethertest/example004-expected.png differ
diff --git a/tests/regression/throwntogethertest/example005-expected.png b/tests/regression/throwntogethertest/example005-expected.png
new file mode 100644
index 00000000..4c401dad
Binary files /dev/null and b/tests/regression/throwntogethertest/example005-expected.png differ
diff --git a/tests/regression/throwntogethertest/example006-expected.png b/tests/regression/throwntogethertest/example006-expected.png
new file mode 100644
index 00000000..66441bfd
Binary files /dev/null and b/tests/regression/throwntogethertest/example006-expected.png differ
diff --git a/tests/regression/throwntogethertest/example007-expected.png b/tests/regression/throwntogethertest/example007-expected.png
new file mode 100644
index 00000000..ea17570c
Binary files /dev/null and b/tests/regression/throwntogethertest/example007-expected.png differ
diff --git a/tests/regression/throwntogethertest/example008-expected.png b/tests/regression/throwntogethertest/example008-expected.png
new file mode 100644
index 00000000..880844bd
Binary files /dev/null and b/tests/regression/throwntogethertest/example008-expected.png differ
diff --git a/tests/regression/throwntogethertest/example009-expected.png b/tests/regression/throwntogethertest/example009-expected.png
new file mode 100644
index 00000000..de8868a2
Binary files /dev/null and b/tests/regression/throwntogethertest/example009-expected.png differ
diff --git a/tests/regression/throwntogethertest/example010-expected.png b/tests/regression/throwntogethertest/example010-expected.png
new file mode 100644
index 00000000..37e65456
Binary files /dev/null and b/tests/regression/throwntogethertest/example010-expected.png differ
diff --git a/tests/regression/throwntogethertest/example011-expected.png b/tests/regression/throwntogethertest/example011-expected.png
new file mode 100644
index 00000000..13164c3e
Binary files /dev/null and b/tests/regression/throwntogethertest/example011-expected.png differ
diff --git a/tests/regression/throwntogethertest/example012-expected.png b/tests/regression/throwntogethertest/example012-expected.png
new file mode 100644
index 00000000..360d6eb5
Binary files /dev/null and b/tests/regression/throwntogethertest/example012-expected.png differ
diff --git a/tests/regression/throwntogethertest/example013-expected.png b/tests/regression/throwntogethertest/example013-expected.png
new file mode 100644
index 00000000..d22b68f0
Binary files /dev/null and b/tests/regression/throwntogethertest/example013-expected.png differ
diff --git a/tests/regression/throwntogethertest/example014-expected.png b/tests/regression/throwntogethertest/example014-expected.png
new file mode 100644
index 00000000..562ce746
Binary files /dev/null and b/tests/regression/throwntogethertest/example014-expected.png differ
diff --git a/tests/regression/throwntogethertest/example015-expected.png b/tests/regression/throwntogethertest/example015-expected.png
new file mode 100644
index 00000000..6e16e33f
Binary files /dev/null and b/tests/regression/throwntogethertest/example015-expected.png differ
diff --git a/tests/regression/throwntogethertest/example016-expected.png b/tests/regression/throwntogethertest/example016-expected.png
new file mode 100644
index 00000000..9bc43066
Binary files /dev/null and b/tests/regression/throwntogethertest/example016-expected.png differ
diff --git a/tests/regression/throwntogethertest/example017-expected.png b/tests/regression/throwntogethertest/example017-expected.png
new file mode 100644
index 00000000..b0b2f8a3
Binary files /dev/null and b/tests/regression/throwntogethertest/example017-expected.png differ
diff --git a/tests/regression/throwntogethertest/example018-expected.png b/tests/regression/throwntogethertest/example018-expected.png
new file mode 100644
index 00000000..033a1365
Binary files /dev/null and b/tests/regression/throwntogethertest/example018-expected.png differ
diff --git a/tests/regression/throwntogethertest/example019-expected.png b/tests/regression/throwntogethertest/example019-expected.png
new file mode 100644
index 00000000..306c0fb7
Binary files /dev/null and b/tests/regression/throwntogethertest/example019-expected.png differ
diff --git a/tests/regression/throwntogethertest/example020-expected.png b/tests/regression/throwntogethertest/example020-expected.png
new file mode 100644
index 00000000..fa41d2f9
Binary files /dev/null and b/tests/regression/throwntogethertest/example020-expected.png differ
diff --git a/tests/regression/throwntogethertest/example021-expected.png b/tests/regression/throwntogethertest/example021-expected.png
new file mode 100644
index 00000000..1e1576cf
Binary files /dev/null and b/tests/regression/throwntogethertest/example021-expected.png differ
diff --git a/tests/regression/throwntogethertest/example022-expected.png b/tests/regression/throwntogethertest/example022-expected.png
new file mode 100644
index 00000000..66738e0b
Binary files /dev/null and b/tests/regression/throwntogethertest/example022-expected.png differ