diff --git a/testmaps/glasstest.map b/testmaps/glasstest.map
new file mode 100644
index 00000000..9a53b2ab
--- /dev/null
+++ b/testmaps/glasstest.map
@@ -0,0 +1,221 @@
+// Game: Quake
+// Format: Standard
+// entity 0
+{
+"classname" "worldspawn"
+"wad" "free_wad.wad"
+"_sunlight2" "200"
+"_sun_mangle" "330 -60 0"
+"_sunlight" "100"
+"_sunlight_color" "100 150 255"
+// brush 0
+{
+( 512 64 816 ) ( 512 64 817 ) ( 512 65 816 ) brown 0 0 0 1 1
+( -1472 -64 784 ) ( -1472 -63 784 ) ( -1472 -64 785 ) brown -0 -0 -0 1 1
+( 64 704 816 ) ( 65 704 816 ) ( 64 704 817 ) brown -0 -0 -0 1 1
+( -64 -320 784 ) ( -64 -320 785 ) ( -63 -320 784 ) brown 0 0 0 1 1
+( 64 64 816 ) ( 64 65 816 ) ( 65 64 816 ) brown 0 0 0 1 1
+( -64 -64 800 ) ( -63 -64 800 ) ( -64 -63 800 ) brown 0 0 0 1 1
+}
+// brush 1
+{
+( 576 704 16 ) ( 576 704 17 ) ( 576 705 16 ) brown -0 -0 -0 1 1
+( -1472 576 -16 ) ( -1472 577 -16 ) ( -1472 576 -15 ) brown -0 -0 -0 1 1
+( -96 672 16 ) ( -95 672 16 ) ( -96 672 17 ) brown 64 -0 -0 1 1
+( -224 640 -16 ) ( -224 640 -15 ) ( -223 640 -16 ) brown 64 -0 -0 1 1
+( -96 704 800 ) ( -96 705 800 ) ( -95 704 800 ) brown 64 -0 -0 1 1
+( -224 576 -16 ) ( -223 576 -16 ) ( -224 577 -16 ) brown 64 -0 -0 1 1
+}
+// brush 2
+{
+( 544 64 16 ) ( 544 64 17 ) ( 544 65 16 ) brown 0 0 0 1 1
+( 512 -64 -16 ) ( 512 -63 -16 ) ( 512 -64 -15 ) brown 0 0 0 1 1
+( 640 704 16 ) ( 641 704 16 ) ( 640 704 17 ) brown -0 -0 -0 1 1
+( 512 -320 -16 ) ( 512 -320 -15 ) ( 513 -320 -16 ) brown 0 0 0 1 1
+( 640 64 800 ) ( 640 65 800 ) ( 641 64 800 ) brown 0 0 0 1 1
+( 512 -64 -16 ) ( 513 -64 -16 ) ( 512 -63 -16 ) brown 0 0 0 1 1
+}
+// brush 3
+{
+( -1472 64 16 ) ( -1472 64 17 ) ( -1472 65 16 ) brown -0 -0 -0 1 1
+( -1504 -64 -16 ) ( -1504 -63 -16 ) ( -1504 -64 -15 ) brown -0 -0 -0 1 1
+( -1376 640 16 ) ( -1375 640 16 ) ( -1376 640 17 ) brown -0 -0 -0 1 1
+( -1504 -320 -16 ) ( -1504 -320 -15 ) ( -1503 -320 -16 ) brown -0 -0 -0 1 1
+( -1376 64 800 ) ( -1376 65 800 ) ( -1375 64 800 ) brown -0 -0 -0 1 1
+( -1504 -64 -16 ) ( -1503 -64 -16 ) ( -1504 -63 -16 ) brown -0 -0 -0 1 1
+}
+// brush 4
+{
+( 544 -288 16 ) ( 544 -288 17 ) ( 544 -287 16 ) brown 0 0 0 1 1
+( -1472 -416 -16 ) ( -1472 -415 -16 ) ( -1472 -416 -15 ) brown -0 -0 -0 1 1
+( 64 -320 16 ) ( 65 -320 16 ) ( 64 -320 17 ) brown 0 0 0 1 1
+( -64 -352 -16 ) ( -64 -352 -15 ) ( -63 -352 -16 ) brown 0 0 0 1 1
+( 64 -288 800 ) ( 64 -287 800 ) ( 65 -288 800 ) brown 0 0 0 1 1
+( -64 -416 -16 ) ( -63 -416 -16 ) ( -64 -415 -16 ) brown 0 0 0 1 1
+}
+// brush 5
+{
+( 528 64 16 ) ( 528 64 17 ) ( 528 65 16 ) gbstone 0 0 0 1 1
+( -1472 -64 -16 ) ( -1472 -63 -16 ) ( -1472 -64 -15 ) gbstone -0 -0 -0 1 1
+( 64 704 16 ) ( 65 704 16 ) ( 64 704 17 ) gbstone -0 -0 -0 1 1
+( -64 -320 -16 ) ( -64 -320 -15 ) ( -63 -320 -16 ) gbstone 0 0 0 1 1
+( 64 64 16 ) ( 64 65 16 ) ( 65 64 16 ) gbstone 0 0 0 1 1
+( -64 -64 -16 ) ( -63 -64 -16 ) ( -64 -63 -16 ) gbstone 0 0 0 1 1
+}
+}
+// entity 1
+{
+"classname" "info_player_start"
+"origin" "-416 -224 40"
+"angle" "90"
+}
+// entity 2
+{
+"classname" "light_globe"
+"origin" "-584 512 72"
+"angle" "-0"
+"target" "t1"
+"delay" "2"
+}
+// entity 3
+{
+"classname" "info_null"
+"origin" "-584 384 40"
+"angle" "90"
+"targetname" "t1"
+}
+// entity 4
+{
+"classname" "func_wall"
+"_shadow" "1"
+"alpha" "0.25"
+// brush 0
+{
+( -648 440 16 ) ( -648 424 32 ) ( -648 424 16 ) spipe2 8 -0 180 1 -1
+( -648 440 16 ) ( -520 440 32 ) ( -648 440 32 ) hazard 7.99997 16 -0 1 1
+( -648 440 16 ) ( -520 424 16 ) ( -520 440 16 ) spipe2 8.00024 -7.99963 270 1 1
+( -648 440 144 ) ( -520 424 144 ) ( -648 424 144 ) spipe2 8.00024 -7.99963 270 1 1
+( -520 440 16 ) ( -520 424 32 ) ( -520 440 32 ) spipe2 8 -0 180 1 -1
+( -648 424 16 ) ( -520 424 32 ) ( -520 424 16 ) blood4 7.99997 0 -0 1 1
+}
+}
+// entity 5
+{
+"classname" "light_globe"
+"origin" "-328 512 72"
+"angle" "-0"
+"target" "t2"
+"delay" "2"
+}
+// entity 6
+{
+"classname" "func_wall"
+"_shadow" "1"
+"alpha" "0.5"
+// brush 0
+{
+( -392 440 16 ) ( -392 424 32 ) ( -392 424 16 ) spipe2 8 -0 180 1 -1
+( -392 440 16 ) ( -264 440 32 ) ( -392 440 32 ) hazard -56 16 -0 1 1
+( -392 440 16 ) ( -264 424 16 ) ( -264 440 16 ) spipe2 8 8.00034 270 1 1
+( -392 440 144 ) ( -264 424 144 ) ( -392 424 144 ) spipe2 8 8.00034 270 1 1
+( -264 440 16 ) ( -264 424 32 ) ( -264 440 32 ) spipe2 8 -0 180 1 -1
+( -392 424 16 ) ( -264 424 32 ) ( -264 424 16 ) blood4 -56 0 -0 1 1
+}
+}
+// entity 7
+{
+"classname" "info_null"
+"origin" "-328 384 40"
+"angle" "90"
+"targetname" "t2"
+}
+// entity 8
+{
+"classname" "func_wall"
+"_shadow" "1"
+"alpha" "0.75"
+// brush 0
+{
+( -136 440 16 ) ( -136 424 32 ) ( -136 424 16 ) spipe2 8 -0 180 1 -1
+( -136 440 16 ) ( -8 440 32 ) ( -136 440 32 ) hazard -56 16 -0 1 1
+( -136 440 16 ) ( -8 424 16 ) ( -8 440 16 ) spipe2 7.99988 8.00024 270 1 1
+( -136 440 144 ) ( -8 424 144 ) ( -136 424 144 ) spipe2 7.99988 8.00024 270 1 1
+( -8 440 16 ) ( -8 424 32 ) ( -8 440 32 ) spipe2 8 -0 180 1 -1
+( -136 424 16 ) ( -8 424 32 ) ( -8 424 16 ) blood4 -56 0 -0 1 1
+}
+}
+// entity 9
+{
+"classname" "light_globe"
+"origin" "-72 512 72"
+"angle" "-0"
+"target" "t3"
+"delay" "2"
+}
+// entity 10
+{
+"classname" "info_null"
+"origin" "-72 384 40"
+"angle" "90"
+"targetname" "t3"
+}
+// entity 11
+{
+"classname" "light_globe"
+"origin" "248 512 72"
+"angle" "-0"
+"target" "t4"
+"delay" "2"
+}
+// entity 12
+{
+"classname" "func_wall"
+"_shadow" "1"
+"alpha" "1"
+// brush 0
+{
+( 184 440 16 ) ( 184 424 32 ) ( 184 424 16 ) spipe2 8 -0 180 1 -1
+( 184 440 16 ) ( 312 440 32 ) ( 184 440 32 ) hazard -56 16 -0 1 1
+( 184 440 16 ) ( 312 424 16 ) ( 312 440 16 ) spipe2 7.99974 8.00024 270 1 1
+( 184 440 144 ) ( 312 424 144 ) ( 184 424 144 ) spipe2 7.99974 8.00024 270 1 1
+( 312 440 16 ) ( 312 424 32 ) ( 312 440 32 ) spipe2 8 -0 180 1 -1
+( 184 424 16 ) ( 312 424 32 ) ( 312 424 16 ) blood4 -56 0 -0 1 1
+}
+}
+// entity 13
+{
+"classname" "info_null"
+"origin" "248 384 40"
+"angle" "90"
+"targetname" "t4"
+}
+// entity 14
+{
+"classname" "func_wall"
+"_shadow" "1"
+"alpha" "0.001"
+// brush 0
+{
+( -904 440 16 ) ( -904 424 32 ) ( -904 424 16 ) spipe2 8 -0 180 1 -1
+( -904 440 16 ) ( -776 440 32 ) ( -904 440 32 ) hazard 7.99997 16 -0 1 1
+( -904 440 16 ) ( -776 424 16 ) ( -776 440 16 ) spipe2 8.00037 -7.99954 270 1 1
+( -904 440 144 ) ( -776 424 144 ) ( -904 424 144 ) spipe2 8.00037 -7.99954 270 1 1
+( -776 440 16 ) ( -776 424 32 ) ( -776 440 32 ) spipe2 8 -0 180 1 -1
+( -904 424 16 ) ( -776 424 32 ) ( -776 424 16 ) blood4 7.99997 0 -0 1 1
+}
+}
+// entity 15
+{
+"classname" "light_globe"
+"origin" "-840 512 72"
+"angle" "-0"
+"target" "t0"
+"delay" "2"
+}
+// entity 16
+{
+"classname" "info_null"
+"origin" "-840 384 40"
+"angle" "90"
+"targetname" "t0"
+}