# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1361152012 -7200
# Node ID e09cbb2e9d4f8c46bb488bca00838d9c54c804c8
# Parent  5fb21401b7c8d76412fd6b7d92ff61dec683d515
metaballs

diff -r 5fb21401b7c8 -r e09cbb2e9d4f Makefile
--- a/Makefile	Thu Feb 07 18:52:28 2013 +0200
+++ b/Makefile	Mon Feb 18 03:46:52 2013 +0200
@@ -1,12 +1,13 @@
-csrc = $(wildcard src/*.c)
+csrc = $(wildcard src/*.c) \
+	   $(wildcard libs/metasurf/*.c)
 ccsrc = $(wildcard src/*.cc)
 obj = $(csrc:.c=.o) $(ccsrc:.cc=.o)
 dep = $(obj:.o=.d)
 bin = udg
 
-CFLAGS = -pedantic -Wall -g
+CFLAGS = -pedantic -Wall -g -O3 -Ilibs/metasurf
 CXXFLAGS = -std=c++11 $(CFLAGS)
-LDFLAGS = $(libgl) -limago
+LDFLAGS = $(libgl) -limago -lvmath
 
 ifeq ($(shell uname -s), Darwin)
 	libgl = -framework OpenGL -framework GLUT -lGLEW
diff -r 5fb21401b7c8 -r e09cbb2e9d4f libs/metasurf/mcubes.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libs/metasurf/mcubes.h	Mon Feb 18 03:46:52 2013 +0200
@@ -0,0 +1,294 @@
+static int mc_edge_table[256] = {
+	0x0  , 0x109, 0x203, 0x30a, 0x406, 0x50f, 0x605, 0x70c,
+	0x80c, 0x905, 0xa0f, 0xb06, 0xc0a, 0xd03, 0xe09, 0xf00,
+	0x190, 0x99 , 0x393, 0x29a, 0x596, 0x49f, 0x795, 0x69c,
+	0x99c, 0x895, 0xb9f, 0xa96, 0xd9a, 0xc93, 0xf99, 0xe90,
+	0x230, 0x339, 0x33 , 0x13a, 0x636, 0x73f, 0x435, 0x53c,
+	0xa3c, 0xb35, 0x83f, 0x936, 0xe3a, 0xf33, 0xc39, 0xd30,
+	0x3a0, 0x2a9, 0x1a3, 0xaa , 0x7a6, 0x6af, 0x5a5, 0x4ac,
+	0xbac, 0xaa5, 0x9af, 0x8a6, 0xfaa, 0xea3, 0xda9, 0xca0,
+	0x460, 0x569, 0x663, 0x76a, 0x66 , 0x16f, 0x265, 0x36c,
+	0xc6c, 0xd65, 0xe6f, 0xf66, 0x86a, 0x963, 0xa69, 0xb60,
+	0x5f0, 0x4f9, 0x7f3, 0x6fa, 0x1f6, 0xff , 0x3f5, 0x2fc,
+	0xdfc, 0xcf5, 0xfff, 0xef6, 0x9fa, 0x8f3, 0xbf9, 0xaf0,
+	0x650, 0x759, 0x453, 0x55a, 0x256, 0x35f, 0x55 , 0x15c,
+	0xe5c, 0xf55, 0xc5f, 0xd56, 0xa5a, 0xb53, 0x859, 0x950,
+	0x7c0, 0x6c9, 0x5c3, 0x4ca, 0x3c6, 0x2cf, 0x1c5, 0xcc ,
+	0xfcc, 0xec5, 0xdcf, 0xcc6, 0xbca, 0xac3, 0x9c9, 0x8c0,
+	0x8c0, 0x9c9, 0xac3, 0xbca, 0xcc6, 0xdcf, 0xec5, 0xfcc,
+	0xcc , 0x1c5, 0x2cf, 0x3c6, 0x4ca, 0x5c3, 0x6c9, 0x7c0,
+	0x950, 0x859, 0xb53, 0xa5a, 0xd56, 0xc5f, 0xf55, 0xe5c,
+	0x15c, 0x55 , 0x35f, 0x256, 0x55a, 0x453, 0x759, 0x650,
+	0xaf0, 0xbf9, 0x8f3, 0x9fa, 0xef6, 0xfff, 0xcf5, 0xdfc,
+	0x2fc, 0x3f5, 0xff , 0x1f6, 0x6fa, 0x7f3, 0x4f9, 0x5f0,
+	0xb60, 0xa69, 0x963, 0x86a, 0xf66, 0xe6f, 0xd65, 0xc6c,
+	0x36c, 0x265, 0x16f, 0x66 , 0x76a, 0x663, 0x569, 0x460,
+	0xca0, 0xda9, 0xea3, 0xfaa, 0x8a6, 0x9af, 0xaa5, 0xbac,
+	0x4ac, 0x5a5, 0x6af, 0x7a6, 0xaa , 0x1a3, 0x2a9, 0x3a0,
+	0xd30, 0xc39, 0xf33, 0xe3a, 0x936, 0x83f, 0xb35, 0xa3c,
+	0x53c, 0x435, 0x73f, 0x636, 0x13a, 0x33 , 0x339, 0x230,
+	0xe90, 0xf99, 0xc93, 0xd9a, 0xa96, 0xb9f, 0x895, 0x99c,
+	0x69c, 0x795, 0x49f, 0x596, 0x29a, 0x393, 0x99 , 0x190,
+	0xf00, 0xe09, 0xd03, 0xc0a, 0xb06, 0xa0f, 0x905, 0x80c,
+	0x70c, 0x605, 0x50f, 0x406, 0x30a, 0x203, 0x109, 0x0
+};
+
+
+static int mc_tri_table[256][16] = {
+	{-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 1, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 8, 3, 9, 8, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 10, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 3, 1, 2, 10, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{9, 2, 10, 0, 2, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{2, 8, 3, 2, 10, 8, 10, 9, 8, -1, -1, -1, -1, -1, -1, -1},
+	{3, 11, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 11, 2, 8, 11, 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 9, 0, 2, 3, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 11, 2, 1, 9, 11, 9, 8, 11, -1, -1, -1, -1, -1, -1, -1},
+	{3, 10, 1, 11, 10, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 10, 1, 0, 8, 10, 8, 11, 10, -1, -1, -1, -1, -1, -1, -1},
+	{3, 9, 0, 3, 11, 9, 11, 10, 9, -1, -1, -1, -1, -1, -1, -1},
+	{9, 8, 10, 10, 8, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 3, 0, 7, 3, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 1, 9, 8, 4, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 1, 9, 4, 7, 1, 7, 3, 1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 10, 8, 4, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{3, 4, 7, 3, 0, 4, 1, 2, 10, -1, -1, -1, -1, -1, -1, -1},
+	{9, 2, 10, 9, 0, 2, 8, 4, 7, -1, -1, -1, -1, -1, -1, -1},
+	{2, 10, 9, 2, 9, 7, 2, 7, 3, 7, 9, 4, -1, -1, -1, -1},
+	{8, 4, 7, 3, 11, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{11, 4, 7, 11, 2, 4, 2, 0, 4, -1, -1, -1, -1, -1, -1, -1},
+	{9, 0, 1, 8, 4, 7, 2, 3, 11, -1, -1, -1, -1, -1, -1, -1},
+	{4, 7, 11, 9, 4, 11, 9, 11, 2, 9, 2, 1, -1, -1, -1, -1},
+	{3, 10, 1, 3, 11, 10, 7, 8, 4, -1, -1, -1, -1, -1, -1, -1},
+	{1, 11, 10, 1, 4, 11, 1, 0, 4, 7, 11, 4, -1, -1, -1, -1},
+	{4, 7, 8, 9, 0, 11, 9, 11, 10, 11, 0, 3, -1, -1, -1, -1},
+	{4, 7, 11, 4, 11, 9, 9, 11, 10, -1, -1, -1, -1, -1, -1, -1},
+	{9, 5, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{9, 5, 4, 0, 8, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 5, 4, 1, 5, 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{8, 5, 4, 8, 3, 5, 3, 1, 5, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 10, 9, 5, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{3, 0, 8, 1, 2, 10, 4, 9, 5, -1, -1, -1, -1, -1, -1, -1},
+	{5, 2, 10, 5, 4, 2, 4, 0, 2, -1, -1, -1, -1, -1, -1, -1},
+	{2, 10, 5, 3, 2, 5, 3, 5, 4, 3, 4, 8, -1, -1, -1, -1},
+	{9, 5, 4, 2, 3, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 11, 2, 0, 8, 11, 4, 9, 5, -1, -1, -1, -1, -1, -1, -1},
+	{0, 5, 4, 0, 1, 5, 2, 3, 11, -1, -1, -1, -1, -1, -1, -1},
+	{2, 1, 5, 2, 5, 8, 2, 8, 11, 4, 8, 5, -1, -1, -1, -1},
+	{10, 3, 11, 10, 1, 3, 9, 5, 4, -1, -1, -1, -1, -1, -1, -1},
+	{4, 9, 5, 0, 8, 1, 8, 10, 1, 8, 11, 10, -1, -1, -1, -1},
+	{5, 4, 0, 5, 0, 11, 5, 11, 10, 11, 0, 3, -1, -1, -1, -1},
+	{5, 4, 8, 5, 8, 10, 10, 8, 11, -1, -1, -1, -1, -1, -1, -1},
+	{9, 7, 8, 5, 7, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{9, 3, 0, 9, 5, 3, 5, 7, 3, -1, -1, -1, -1, -1, -1, -1},
+	{0, 7, 8, 0, 1, 7, 1, 5, 7, -1, -1, -1, -1, -1, -1, -1},
+	{1, 5, 3, 3, 5, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{9, 7, 8, 9, 5, 7, 10, 1, 2, -1, -1, -1, -1, -1, -1, -1},
+	{10, 1, 2, 9, 5, 0, 5, 3, 0, 5, 7, 3, -1, -1, -1, -1},
+	{8, 0, 2, 8, 2, 5, 8, 5, 7, 10, 5, 2, -1, -1, -1, -1},
+	{2, 10, 5, 2, 5, 3, 3, 5, 7, -1, -1, -1, -1, -1, -1, -1},
+	{7, 9, 5, 7, 8, 9, 3, 11, 2, -1, -1, -1, -1, -1, -1, -1},
+	{9, 5, 7, 9, 7, 2, 9, 2, 0, 2, 7, 11, -1, -1, -1, -1},
+	{2, 3, 11, 0, 1, 8, 1, 7, 8, 1, 5, 7, -1, -1, -1, -1},
+	{11, 2, 1, 11, 1, 7, 7, 1, 5, -1, -1, -1, -1, -1, -1, -1},
+	{9, 5, 8, 8, 5, 7, 10, 1, 3, 10, 3, 11, -1, -1, -1, -1},
+	{5, 7, 0, 5, 0, 9, 7, 11, 0, 1, 0, 10, 11, 10, 0, -1},
+	{11, 10, 0, 11, 0, 3, 10, 5, 0, 8, 0, 7, 5, 7, 0, -1},
+	{11, 10, 5, 7, 11, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{10, 6, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 3, 5, 10, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{9, 0, 1, 5, 10, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 8, 3, 1, 9, 8, 5, 10, 6, -1, -1, -1, -1, -1, -1, -1},
+	{1, 6, 5, 2, 6, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 6, 5, 1, 2, 6, 3, 0, 8, -1, -1, -1, -1, -1, -1, -1},
+	{9, 6, 5, 9, 0, 6, 0, 2, 6, -1, -1, -1, -1, -1, -1, -1},
+	{5, 9, 8, 5, 8, 2, 5, 2, 6, 3, 2, 8, -1, -1, -1, -1},
+	{2, 3, 11, 10, 6, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{11, 0, 8, 11, 2, 0, 10, 6, 5, -1, -1, -1, -1, -1, -1, -1},
+	{0, 1, 9, 2, 3, 11, 5, 10, 6, -1, -1, -1, -1, -1, -1, -1},
+	{5, 10, 6, 1, 9, 2, 9, 11, 2, 9, 8, 11, -1, -1, -1, -1},
+	{6, 3, 11, 6, 5, 3, 5, 1, 3, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 11, 0, 11, 5, 0, 5, 1, 5, 11, 6, -1, -1, -1, -1},
+	{3, 11, 6, 0, 3, 6, 0, 6, 5, 0, 5, 9, -1, -1, -1, -1},
+	{6, 5, 9, 6, 9, 11, 11, 9, 8, -1, -1, -1, -1, -1, -1, -1},
+	{5, 10, 6, 4, 7, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 3, 0, 4, 7, 3, 6, 5, 10, -1, -1, -1, -1, -1, -1, -1},
+	{1, 9, 0, 5, 10, 6, 8, 4, 7, -1, -1, -1, -1, -1, -1, -1},
+	{10, 6, 5, 1, 9, 7, 1, 7, 3, 7, 9, 4, -1, -1, -1, -1},
+	{6, 1, 2, 6, 5, 1, 4, 7, 8, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 5, 5, 2, 6, 3, 0, 4, 3, 4, 7, -1, -1, -1, -1},
+	{8, 4, 7, 9, 0, 5, 0, 6, 5, 0, 2, 6, -1, -1, -1, -1},
+	{7, 3, 9, 7, 9, 4, 3, 2, 9, 5, 9, 6, 2, 6, 9, -1},
+	{3, 11, 2, 7, 8, 4, 10, 6, 5, -1, -1, -1, -1, -1, -1, -1},
+	{5, 10, 6, 4, 7, 2, 4, 2, 0, 2, 7, 11, -1, -1, -1, -1},
+	{0, 1, 9, 4, 7, 8, 2, 3, 11, 5, 10, 6, -1, -1, -1, -1},
+	{9, 2, 1, 9, 11, 2, 9, 4, 11, 7, 11, 4, 5, 10, 6, -1},
+	{8, 4, 7, 3, 11, 5, 3, 5, 1, 5, 11, 6, -1, -1, -1, -1},
+	{5, 1, 11, 5, 11, 6, 1, 0, 11, 7, 11, 4, 0, 4, 11, -1},
+	{0, 5, 9, 0, 6, 5, 0, 3, 6, 11, 6, 3, 8, 4, 7, -1},
+	{6, 5, 9, 6, 9, 11, 4, 7, 9, 7, 11, 9, -1, -1, -1, -1},
+	{10, 4, 9, 6, 4, 10, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 10, 6, 4, 9, 10, 0, 8, 3, -1, -1, -1, -1, -1, -1, -1},
+	{10, 0, 1, 10, 6, 0, 6, 4, 0, -1, -1, -1, -1, -1, -1, -1},
+	{8, 3, 1, 8, 1, 6, 8, 6, 4, 6, 1, 10, -1, -1, -1, -1},
+	{1, 4, 9, 1, 2, 4, 2, 6, 4, -1, -1, -1, -1, -1, -1, -1},
+	{3, 0, 8, 1, 2, 9, 2, 4, 9, 2, 6, 4, -1, -1, -1, -1},
+	{0, 2, 4, 4, 2, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{8, 3, 2, 8, 2, 4, 4, 2, 6, -1, -1, -1, -1, -1, -1, -1},
+	{10, 4, 9, 10, 6, 4, 11, 2, 3, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 2, 2, 8, 11, 4, 9, 10, 4, 10, 6, -1, -1, -1, -1},
+	{3, 11, 2, 0, 1, 6, 0, 6, 4, 6, 1, 10, -1, -1, -1, -1},
+	{6, 4, 1, 6, 1, 10, 4, 8, 1, 2, 1, 11, 8, 11, 1, -1},
+	{9, 6, 4, 9, 3, 6, 9, 1, 3, 11, 6, 3, -1, -1, -1, -1},
+	{8, 11, 1, 8, 1, 0, 11, 6, 1, 9, 1, 4, 6, 4, 1, -1},
+	{3, 11, 6, 3, 6, 0, 0, 6, 4, -1, -1, -1, -1, -1, -1, -1},
+	{6, 4, 8, 11, 6, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{7, 10, 6, 7, 8, 10, 8, 9, 10, -1, -1, -1, -1, -1, -1, -1},
+	{0, 7, 3, 0, 10, 7, 0, 9, 10, 6, 7, 10, -1, -1, -1, -1},
+	{10, 6, 7, 1, 10, 7, 1, 7, 8, 1, 8, 0, -1, -1, -1, -1},
+	{10, 6, 7, 10, 7, 1, 1, 7, 3, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 6, 1, 6, 8, 1, 8, 9, 8, 6, 7, -1, -1, -1, -1},
+	{2, 6, 9, 2, 9, 1, 6, 7, 9, 0, 9, 3, 7, 3, 9, -1},
+	{7, 8, 0, 7, 0, 6, 6, 0, 2, -1, -1, -1, -1, -1, -1, -1},
+	{7, 3, 2, 6, 7, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{2, 3, 11, 10, 6, 8, 10, 8, 9, 8, 6, 7, -1, -1, -1, -1},
+	{2, 0, 7, 2, 7, 11, 0, 9, 7, 6, 7, 10, 9, 10, 7, -1},
+	{1, 8, 0, 1, 7, 8, 1, 10, 7, 6, 7, 10, 2, 3, 11, -1},
+	{11, 2, 1, 11, 1, 7, 10, 6, 1, 6, 7, 1, -1, -1, -1, -1},
+	{8, 9, 6, 8, 6, 7, 9, 1, 6, 11, 6, 3, 1, 3, 6, -1},
+	{0, 9, 1, 11, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{7, 8, 0, 7, 0, 6, 3, 11, 0, 11, 6, 0, -1, -1, -1, -1},
+	{7, 11, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{7, 6, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{3, 0, 8, 11, 7, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 1, 9, 11, 7, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{8, 1, 9, 8, 3, 1, 11, 7, 6, -1, -1, -1, -1, -1, -1, -1},
+	{10, 1, 2, 6, 11, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 10, 3, 0, 8, 6, 11, 7, -1, -1, -1, -1, -1, -1, -1},
+	{2, 9, 0, 2, 10, 9, 6, 11, 7, -1, -1, -1, -1, -1, -1, -1},
+	{6, 11, 7, 2, 10, 3, 10, 8, 3, 10, 9, 8, -1, -1, -1, -1},
+	{7, 2, 3, 6, 2, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{7, 0, 8, 7, 6, 0, 6, 2, 0, -1, -1, -1, -1, -1, -1, -1},
+	{2, 7, 6, 2, 3, 7, 0, 1, 9, -1, -1, -1, -1, -1, -1, -1},
+	{1, 6, 2, 1, 8, 6, 1, 9, 8, 8, 7, 6, -1, -1, -1, -1},
+	{10, 7, 6, 10, 1, 7, 1, 3, 7, -1, -1, -1, -1, -1, -1, -1},
+	{10, 7, 6, 1, 7, 10, 1, 8, 7, 1, 0, 8, -1, -1, -1, -1},
+	{0, 3, 7, 0, 7, 10, 0, 10, 9, 6, 10, 7, -1, -1, -1, -1},
+	{7, 6, 10, 7, 10, 8, 8, 10, 9, -1, -1, -1, -1, -1, -1, -1},
+	{6, 8, 4, 11, 8, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{3, 6, 11, 3, 0, 6, 0, 4, 6, -1, -1, -1, -1, -1, -1, -1},
+	{8, 6, 11, 8, 4, 6, 9, 0, 1, -1, -1, -1, -1, -1, -1, -1},
+	{9, 4, 6, 9, 6, 3, 9, 3, 1, 11, 3, 6, -1, -1, -1, -1},
+	{6, 8, 4, 6, 11, 8, 2, 10, 1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 10, 3, 0, 11, 0, 6, 11, 0, 4, 6, -1, -1, -1, -1},
+	{4, 11, 8, 4, 6, 11, 0, 2, 9, 2, 10, 9, -1, -1, -1, -1},
+	{10, 9, 3, 10, 3, 2, 9, 4, 3, 11, 3, 6, 4, 6, 3, -1},
+	{8, 2, 3, 8, 4, 2, 4, 6, 2, -1, -1, -1, -1, -1, -1, -1},
+	{0, 4, 2, 4, 6, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 9, 0, 2, 3, 4, 2, 4, 6, 4, 3, 8, -1, -1, -1, -1},
+	{1, 9, 4, 1, 4, 2, 2, 4, 6, -1, -1, -1, -1, -1, -1, -1},
+	{8, 1, 3, 8, 6, 1, 8, 4, 6, 6, 10, 1, -1, -1, -1, -1},
+	{10, 1, 0, 10, 0, 6, 6, 0, 4, -1, -1, -1, -1, -1, -1, -1},
+	{4, 6, 3, 4, 3, 8, 6, 10, 3, 0, 3, 9, 10, 9, 3, -1},
+	{10, 9, 4, 6, 10, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 9, 5, 7, 6, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 3, 4, 9, 5, 11, 7, 6, -1, -1, -1, -1, -1, -1, -1},
+	{5, 0, 1, 5, 4, 0, 7, 6, 11, -1, -1, -1, -1, -1, -1, -1},
+	{11, 7, 6, 8, 3, 4, 3, 5, 4, 3, 1, 5, -1, -1, -1, -1},
+	{9, 5, 4, 10, 1, 2, 7, 6, 11, -1, -1, -1, -1, -1, -1, -1},
+	{6, 11, 7, 1, 2, 10, 0, 8, 3, 4, 9, 5, -1, -1, -1, -1},
+	{7, 6, 11, 5, 4, 10, 4, 2, 10, 4, 0, 2, -1, -1, -1, -1},
+	{3, 4, 8, 3, 5, 4, 3, 2, 5, 10, 5, 2, 11, 7, 6, -1},
+	{7, 2, 3, 7, 6, 2, 5, 4, 9, -1, -1, -1, -1, -1, -1, -1},
+	{9, 5, 4, 0, 8, 6, 0, 6, 2, 6, 8, 7, -1, -1, -1, -1},
+	{3, 6, 2, 3, 7, 6, 1, 5, 0, 5, 4, 0, -1, -1, -1, -1},
+	{6, 2, 8, 6, 8, 7, 2, 1, 8, 4, 8, 5, 1, 5, 8, -1},
+	{9, 5, 4, 10, 1, 6, 1, 7, 6, 1, 3, 7, -1, -1, -1, -1},
+	{1, 6, 10, 1, 7, 6, 1, 0, 7, 8, 7, 0, 9, 5, 4, -1},
+	{4, 0, 10, 4, 10, 5, 0, 3, 10, 6, 10, 7, 3, 7, 10, -1},
+	{7, 6, 10, 7, 10, 8, 5, 4, 10, 4, 8, 10, -1, -1, -1, -1},
+	{6, 9, 5, 6, 11, 9, 11, 8, 9, -1, -1, -1, -1, -1, -1, -1},
+	{3, 6, 11, 0, 6, 3, 0, 5, 6, 0, 9, 5, -1, -1, -1, -1},
+	{0, 11, 8, 0, 5, 11, 0, 1, 5, 5, 6, 11, -1, -1, -1, -1},
+	{6, 11, 3, 6, 3, 5, 5, 3, 1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 10, 9, 5, 11, 9, 11, 8, 11, 5, 6, -1, -1, -1, -1},
+	{0, 11, 3, 0, 6, 11, 0, 9, 6, 5, 6, 9, 1, 2, 10, -1},
+	{11, 8, 5, 11, 5, 6, 8, 0, 5, 10, 5, 2, 0, 2, 5, -1},
+	{6, 11, 3, 6, 3, 5, 2, 10, 3, 10, 5, 3, -1, -1, -1, -1},
+	{5, 8, 9, 5, 2, 8, 5, 6, 2, 3, 8, 2, -1, -1, -1, -1},
+	{9, 5, 6, 9, 6, 0, 0, 6, 2, -1, -1, -1, -1, -1, -1, -1},
+	{1, 5, 8, 1, 8, 0, 5, 6, 8, 3, 8, 2, 6, 2, 8, -1},
+	{1, 5, 6, 2, 1, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 3, 6, 1, 6, 10, 3, 8, 6, 5, 6, 9, 8, 9, 6, -1},
+	{10, 1, 0, 10, 0, 6, 9, 5, 0, 5, 6, 0, -1, -1, -1, -1},
+	{0, 3, 8, 5, 6, 10, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{10, 5, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{11, 5, 10, 7, 5, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{11, 5, 10, 11, 7, 5, 8, 3, 0, -1, -1, -1, -1, -1, -1, -1},
+	{5, 11, 7, 5, 10, 11, 1, 9, 0, -1, -1, -1, -1, -1, -1, -1},
+	{10, 7, 5, 10, 11, 7, 9, 8, 1, 8, 3, 1, -1, -1, -1, -1},
+	{11, 1, 2, 11, 7, 1, 7, 5, 1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 3, 1, 2, 7, 1, 7, 5, 7, 2, 11, -1, -1, -1, -1},
+	{9, 7, 5, 9, 2, 7, 9, 0, 2, 2, 11, 7, -1, -1, -1, -1},
+	{7, 5, 2, 7, 2, 11, 5, 9, 2, 3, 2, 8, 9, 8, 2, -1},
+	{2, 5, 10, 2, 3, 5, 3, 7, 5, -1, -1, -1, -1, -1, -1, -1},
+	{8, 2, 0, 8, 5, 2, 8, 7, 5, 10, 2, 5, -1, -1, -1, -1},
+	{9, 0, 1, 5, 10, 3, 5, 3, 7, 3, 10, 2, -1, -1, -1, -1},
+	{9, 8, 2, 9, 2, 1, 8, 7, 2, 10, 2, 5, 7, 5, 2, -1},
+	{1, 3, 5, 3, 7, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 7, 0, 7, 1, 1, 7, 5, -1, -1, -1, -1, -1, -1, -1},
+	{9, 0, 3, 9, 3, 5, 5, 3, 7, -1, -1, -1, -1, -1, -1, -1},
+	{9, 8, 7, 5, 9, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{5, 8, 4, 5, 10, 8, 10, 11, 8, -1, -1, -1, -1, -1, -1, -1},
+	{5, 0, 4, 5, 11, 0, 5, 10, 11, 11, 3, 0, -1, -1, -1, -1},
+	{0, 1, 9, 8, 4, 10, 8, 10, 11, 10, 4, 5, -1, -1, -1, -1},
+	{10, 11, 4, 10, 4, 5, 11, 3, 4, 9, 4, 1, 3, 1, 4, -1},
+	{2, 5, 1, 2, 8, 5, 2, 11, 8, 4, 5, 8, -1, -1, -1, -1},
+	{0, 4, 11, 0, 11, 3, 4, 5, 11, 2, 11, 1, 5, 1, 11, -1},
+	{0, 2, 5, 0, 5, 9, 2, 11, 5, 4, 5, 8, 11, 8, 5, -1},
+	{9, 4, 5, 2, 11, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{2, 5, 10, 3, 5, 2, 3, 4, 5, 3, 8, 4, -1, -1, -1, -1},
+	{5, 10, 2, 5, 2, 4, 4, 2, 0, -1, -1, -1, -1, -1, -1, -1},
+	{3, 10, 2, 3, 5, 10, 3, 8, 5, 4, 5, 8, 0, 1, 9, -1},
+	{5, 10, 2, 5, 2, 4, 1, 9, 2, 9, 4, 2, -1, -1, -1, -1},
+	{8, 4, 5, 8, 5, 3, 3, 5, 1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 4, 5, 1, 0, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{8, 4, 5, 8, 5, 3, 9, 0, 5, 0, 3, 5, -1, -1, -1, -1},
+	{9, 4, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 11, 7, 4, 9, 11, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1},
+	{0, 8, 3, 4, 9, 7, 9, 11, 7, 9, 10, 11, -1, -1, -1, -1},
+	{1, 10, 11, 1, 11, 4, 1, 4, 0, 7, 4, 11, -1, -1, -1, -1},
+	{3, 1, 4, 3, 4, 8, 1, 10, 4, 7, 4, 11, 10, 11, 4, -1},
+	{4, 11, 7, 9, 11, 4, 9, 2, 11, 9, 1, 2, -1, -1, -1, -1},
+	{9, 7, 4, 9, 11, 7, 9, 1, 11, 2, 11, 1, 0, 8, 3, -1},
+	{11, 7, 4, 11, 4, 2, 2, 4, 0, -1, -1, -1, -1, -1, -1, -1},
+	{11, 7, 4, 11, 4, 2, 8, 3, 4, 3, 2, 4, -1, -1, -1, -1},
+	{2, 9, 10, 2, 7, 9, 2, 3, 7, 7, 4, 9, -1, -1, -1, -1},
+	{9, 10, 7, 9, 7, 4, 10, 2, 7, 8, 7, 0, 2, 0, 7, -1},
+	{3, 7, 10, 3, 10, 2, 7, 4, 10, 1, 10, 0, 4, 0, 10, -1},
+	{1, 10, 2, 8, 7, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 9, 1, 4, 1, 7, 7, 1, 3, -1, -1, -1, -1, -1, -1, -1},
+	{4, 9, 1, 4, 1, 7, 0, 8, 1, 8, 7, 1, -1, -1, -1, -1},
+	{4, 0, 3, 7, 4, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{4, 8, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{9, 10, 8, 10, 11, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{3, 0, 9, 3, 9, 11, 11, 9, 10, -1, -1, -1, -1, -1, -1, -1},
+	{0, 1, 10, 0, 10, 8, 8, 10, 11, -1, -1, -1, -1, -1, -1, -1},
+	{3, 1, 10, 11, 3, 10, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 2, 11, 1, 11, 9, 9, 11, 8, -1, -1, -1, -1, -1, -1, -1},
+	{3, 0, 9, 3, 9, 11, 1, 2, 9, 2, 11, 9, -1, -1, -1, -1},
+	{0, 2, 11, 8, 0, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{3, 2, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{2, 3, 8, 2, 8, 10, 10, 8, 9, -1, -1, -1, -1, -1, -1, -1},
+	{9, 10, 2, 0, 9, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{2, 3, 8, 2, 8, 10, 0, 1, 8, 1, 10, 8, -1, -1, -1, -1},
+	{1, 10, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{1, 3, 8, 9, 1, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 9, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{0, 3, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
+	{-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}
+};
diff -r 5fb21401b7c8 -r e09cbb2e9d4f libs/metasurf/metasurf.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libs/metasurf/metasurf.c	Mon Feb 18 03:46:52 2013 +0200
@@ -0,0 +1,413 @@
+/*
+metasurf - a library for implicit surface polygonization
+Copyright (C) 2011  John Tsiombikas <nuclear@member.fsf.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include <stdio.h>
+#include <stdlib.h>
+#include "metasurf.h"
+#include "mcubes.h"
+
+#undef USE_MTETRA
+#define USE_MCUBES
+
+#if (defined(USE_MTETRA) && defined(USE_MCUBES)) || (!defined(USE_MTETRA) && !defined(USE_MCUBES))
+#error "pick either USE_MTETRA or USE_MCUBES, not both..."
+#endif
+
+typedef float vec3[3];
+
+struct metasurface {
+	vec3 min, max;
+	int res[3];
+	float thres;
+
+	msurf_eval_func_t eval;
+	msurf_vertex_func_t vertex;
+	msurf_normal_func_t normal;
+
+	float dx, dy, dz;
+	int flip;
+
+	vec3 vbuf[3];
+	int nverts;
+};
+
+static int msurf_init(struct metasurface *ms);
+static void process_cell(struct metasurface *ms, vec3 pos, vec3 sz);
+#ifdef USE_MTETRA
+static void process_tetra(struct metasurface *ms, int *idx, vec3 *pos, float *val);
+#endif
+#ifdef USE_MCUBES
+static void process_cube(struct metasurface *ms, vec3 *pos, float *val);
+#endif
+
+
+struct metasurface *msurf_create(void)
+{
+	struct metasurface *ms;
+
+	if(!(ms = malloc(sizeof *ms))) {
+		return 0;
+	}
+	if(msurf_init(ms) == -1) {
+		free(ms);
+	}
+	return ms;
+}
+
+void msurf_free(struct metasurface *ms)
+{
+	free(ms);
+}
+
+static int msurf_init(struct metasurface *ms)
+{
+	ms->thres = 0.0;
+	ms->eval = 0;
+	ms->vertex = 0;
+	ms->normal = 0;
+	ms->min[0] = ms->min[1] = ms->min[2] = -1.0;
+	ms->max[0] = ms->max[1] = ms->max[2] = 1.0;
+	ms->res[0] = ms->res[1] = ms->res[2] = 40;
+	ms->nverts = 0;
+
+	ms->dx = ms->dy = ms->dz = 0.001;
+	ms->flip = 0;
+
+	return 0;
+}
+
+void msurf_inside(struct metasurface *ms, int inside)
+{
+	switch(inside) {
+	case MSURF_GREATER:
+		ms->flip = 0;
+		break;
+
+	case MSURF_LESS:
+		ms->flip = 1;
+		break;
+
+	default:
+		fprintf(stderr, "msurf_inside expects MSURF_GREATER or MSURF_LESS\n");
+	}
+}
+
+void msurf_eval_func(struct metasurface *ms, msurf_eval_func_t func)
+{
+	ms->eval = func;
+}
+
+void msurf_vertex_func(struct metasurface *ms, msurf_vertex_func_t func)
+{
+	ms->vertex = func;
+}
+
+void msurf_normal_func(struct metasurface *ms, msurf_normal_func_t func)
+{
+	ms->normal = func;
+}
+
+void msurf_bounds(struct metasurface *ms, float xmin, float ymin, float zmin, float xmax, float ymax, float zmax)
+{
+	ms->min[0] = xmin;
+	ms->min[1] = ymin;
+	ms->min[2] = zmin;
+	ms->max[0] = xmax;
+	ms->max[1] = ymax;
+	ms->max[2] = zmax;
+}
+
+void msurf_resolution(struct metasurface *ms, int xres, int yres, int zres)
+{
+	ms->res[0] = xres;
+	ms->res[1] = yres;
+	ms->res[2] = zres;
+}
+
+void msurf_threshold(struct metasurface *ms, float thres)
+{
+	ms->thres = thres;
+}
+
+
+int msurf_polygonize(struct metasurface *ms)
+{
+	int i, j, k;
+	vec3 pos, delta;
+
+	if(!ms->eval || !ms->vertex) {
+		fprintf(stderr, "you need to set eval and vertex callbacks before calling msurf_polygonize\n");
+		return -1;
+	}
+
+	for(i=0; i<3; i++) {
+		delta[i] = (ms->max[i] - ms->min[i]) / (float)ms->res[i];
+	}
+
+	pos[0] = ms->min[0];
+	for(i=0; i<ms->res[0] - 1; i++) {
+
+		pos[1] = ms->min[1];
+		for(j=0; j<ms->res[1] - 1; j++) {
+
+			pos[2] = ms->min[2];
+			for(k=0; k<ms->res[2] - 1; k++) {
+
+				process_cell(ms, pos, delta);
+
+				pos[2] += delta[2];
+			}
+			pos[1] += delta[1];
+		}
+		pos[0] += delta[0];
+	}
+	return 0;
+}
+
+
+static void process_cell(struct metasurface *ms, vec3 pos, vec3 sz)
+{
+	int i;
+	vec3 p[8];
+	float val[8];
+
+#ifdef USE_MTETRA
+	static int tetra[][4] = {
+		{0, 2, 3, 7},
+		{0, 2, 6, 7},
+		{0, 4, 6, 7},
+		{0, 6, 1, 2},
+		{0, 6, 1, 4},
+		{5, 6, 1, 4}
+	};
+#endif
+
+	static const float offs[][3] = {
+		{0.0f, 0.0f, 0.0f},
+		{1.0f, 0.0f, 0.0f},
+		{1.0f, 1.0f, 0.0f},
+		{0.0f, 1.0f, 0.0f},
+		{0.0f, 0.0f, 1.0f},
+		{1.0f, 0.0f, 1.0f},
+		{1.0f, 1.0f, 1.0f},
+		{0.0f, 1.0f, 1.0f}
+	};
+
+	for(i=0; i<8; i++) {
+		p[i][0] = pos[0] + sz[0] * offs[i][2];
+		p[i][1] = pos[1] + sz[1] * offs[i][1];
+		p[i][2] = pos[2] + sz[2] * offs[i][0];
+
+		val[i] = ms->eval(p[i][0], p[i][1], p[i][2]);
+	}
+
+#ifdef USE_MTETRA
+	for(i=0; i<6; i++) {
+		process_tetra(ms, tetra[i], p, val);
+	}
+#endif
+#ifdef USE_MCUBES
+	process_cube(ms, p, val);
+#endif
+}
+
+
+/* ---- marching cubes implementation ---- */
+#ifdef USE_MCUBES
+
+static unsigned int mc_bitcode(float *val, float thres);
+
+static void process_cube(struct metasurface *ms, vec3 *pos, float *val)
+{
+	static const int pidx[12][2] = {
+		{0, 1}, {1, 2}, {2, 3}, {3, 0}, {4, 5}, {5, 6},
+		{6, 7},	{7, 4}, {0, 4}, {1, 5}, {2, 6}, {3, 7}
+	};
+	int i, j;
+	vec3 vert[12];
+	unsigned int code = mc_bitcode(val, ms->thres);
+
+	if(ms->flip) {
+		code = ~code & 0xff;
+	}
+
+	if(mc_edge_table[code] == 0) {
+		return;
+	}
+
+	for(i=0; i<12; i++) {
+		if(mc_edge_table[code] & (1 << i)) {
+			int p0 = pidx[i][0];
+			int p1 = pidx[i][1];
+
+			float t = (ms->thres - val[p0]) / (val[p1] - val[p0]);
+			vert[i][0] = pos[p0][0] + (pos[p1][0] - pos[p0][0]) * t;
+			vert[i][1] = pos[p0][1] + (pos[p1][1] - pos[p0][1]) * t;
+			vert[i][2] = pos[p0][2] + (pos[p1][2] - pos[p0][2]) * t;
+		}
+	}
+
+	for(i=0; mc_tri_table[code][i] != -1; i+=3) {
+		for(j=0; j<3; j++) {
+			float *v = vert[mc_tri_table[code][i + j]];
+
+			if(ms->normal) {
+				float dfdx, dfdy, dfdz;
+				dfdx = ms->eval(v[0] - ms->dx, v[1], v[2]) - ms->eval(v[0] + ms->dx, v[1], v[2]);
+				dfdy = ms->eval(v[0], v[1] - ms->dy, v[2]) - ms->eval(v[0], v[1] + ms->dy, v[2]);
+				dfdz = ms->eval(v[0], v[1], v[2] - ms->dz) - ms->eval(v[0], v[1], v[2] + ms->dz);
+
+				if(ms->flip) {
+					dfdx = -dfdx;
+					dfdy = -dfdy;
+					dfdz = -dfdz;
+				}
+				ms->normal(dfdx, dfdy, dfdz);
+			}
+
+			ms->vertex(v[0], v[1], v[2]);
+		}
+	}
+}
+
+static unsigned int mc_bitcode(float *val, float thres)
+{
+	unsigned int i, res = 0;
+
+	for(i=0; i<8; i++) {
+		if(val[i] > thres) {
+			res |= 1 << i;
+		}
+	}
+	return res;
+}
+#endif	/* USE_MCUBES */
+
+
+/* ---- marching tetrahedra implementation (incomplete) ---- */
+#ifdef USE_MTETRA
+
+static unsigned int mt_bitcode(float v0, float v1, float v2, float v3, float thres);
+static void emmit(struct metasurface *ms, float v0, float v1, vec3 p0, vec3 p1, int rev)
+
+
+#define REVBIT(x)	((x) & 8)
+#define INV(x)		(~(x) & 0xf)
+#define EDGE(a, b)	emmit(ms, val[idx[a]], val[idx[b]], pos[idx[a]], pos[idx[b]], REVBIT(code))
+static void process_tetra(struct metasurface *ms, int *idx, vec3 *pos, float *val)
+{
+	unsigned int code = mt_bitcode(val[idx[0]], val[idx[1]], val[idx[2]], val[idx[3]], ms->thres);
+
+	switch(code) {
+	case 1:
+	case INV(1):
+		EDGE(0, 1);
+		EDGE(0, 2);
+		EDGE(0, 3);
+		break;
+
+	case 2:
+	case INV(2):
+		EDGE(1, 0);
+		EDGE(1, 3);
+		EDGE(1, 2);
+		break;
+
+	case 3:
+	case INV(3):
+		EDGE(0, 3);
+		EDGE(0, 2);
+		EDGE(1, 3);
+
+		EDGE(1, 3);
+		EDGE(1, 2);
+		EDGE(0, 2);
+		break;
+
+	case 4:
+	case INV(4):
+		EDGE(2, 0);
+		EDGE(2, 1);
+		EDGE(2, 3);
+		break;
+
+	case 5:
+	case INV(5):
+		EDGE(0, 1);
+		EDGE(2, 3);
+		EDGE(0, 3);
+
+		EDGE(0, 1);
+		EDGE(1, 2);
+		EDGE(2, 3);
+		break;
+
+	case 6:
+	case INV(6):
+		EDGE(0, 1);
+		EDGE(1, 3);
+		EDGE(2, 3);
+
+		EDGE(0, 1);
+		EDGE(0, 2);
+		EDGE(2, 3);
+		break;
+
+	case 7:
+	case INV(7):
+		EDGE(3, 0);
+		EDGE(3, 2);
+		EDGE(3, 1);
+		break;
+
+	default:
+		break;	/* cases 0 and 15 */
+	}
+}
+
+#define BIT(i)	((v##i > thres) ? (1 << i) : 0)
+static unsigned int mt_bitcode(float v0, float v1, float v2, float v3, float thres)
+{
+	return BIT(0) | BIT(1) | BIT(2) | BIT(3);
+}
+
+static void emmit(struct metasurface *ms, float v0, float v1, vec3 p0, vec3 p1, int rev)
+{
+	int i;
+	float t = (ms->thres - v0) / (v1 - v0);
+
+	vec3 p;
+	for(i=0; i<3; i++) {
+		p[i] = p0[i] + (p1[i] - p0[i]) * t;
+	}
+	ms->vertex(p[0], p[1], p[2]);
+
+	/*for(i=0; i<3; i++) {
+		ms->vbuf[ms->nverts][i] = p0[i] + (p1[i] - p0[i]) * t;
+	}
+
+	if(++ms->nverts >= 3) {
+		ms->nverts = 0;
+
+		for(i=0; i<3; i++) {
+			int idx = rev ? (2 - i) : i;
+			ms->vertex(ms->vbuf[idx][0], ms->vbuf[idx][1], ms->vbuf[idx][2]);
+		}
+	}*/
+}
+
+#endif	/* USE_MTETRA */
diff -r 5fb21401b7c8 -r e09cbb2e9d4f libs/metasurf/metasurf.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libs/metasurf/metasurf.h	Mon Feb 18 03:46:52 2013 +0200
@@ -0,0 +1,72 @@
+/*
+metasurf - a library for implicit surface polygonization
+Copyright (C) 2011  John Tsiombikas <nuclear@member.fsf.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef METASURF_H_
+#define METASURF_H_
+
+#define MSURF_GREATER	1
+#define MSURF_LESS		0
+
+struct metasurface;
+
+typedef float (*msurf_eval_func_t)(float, float, float);
+typedef void (*msurf_vertex_func_t)(float, float, float);
+typedef void (*msurf_normal_func_t)(float, float, float);
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct metasurface *msurf_create(void);
+void msurf_free(struct metasurface *ms);
+
+/* which is inside above or below the threshold */
+void msurf_inside(struct metasurface *ms, int inside);
+
+/* set a scalar field evaluator function */
+void msurf_eval_func(struct metasurface *ms, msurf_eval_func_t func);
+
+/* set a generated vertex callback function */
+void msurf_vertex_func(struct metasurface *ms, msurf_vertex_func_t func);
+
+/* set a generated surface normal callback function (unused yet) */
+void msurf_normal_func(struct metasurface *ms, msurf_normal_func_t func);
+
+/* set the bounding box (default: -1, -1, -1, 1, 1, 1)
+ * keep this as tight as possible to avoid wasting grid resolution
+ */
+void msurf_bounds(struct metasurface *ms, float xmin, float ymin, float zmin, float xmax, float ymax, float zmax);
+
+/* resolution of the 3D evaluation grid, the bigger, the better, the slower
+ * (default: 40, 40, 40)
+ */
+void msurf_resolution(struct metasurface *ms, int xres, int yres, int zres);
+
+/* isosurface threshold value (default: 0) */
+void msurf_threshold(struct metasurface *ms, float thres);
+
+
+/* finally call this to perform the polygonization */
+int msurf_polygonize(struct metasurface *ms);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* METASURF_H_ */
diff -r 5fb21401b7c8 -r e09cbb2e9d4f src/mballs.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mballs.cc	Mon Feb 18 03:46:52 2013 +0200
@@ -0,0 +1,140 @@
+#include <vector>
+#include "opengl.h"
+#include "mballs.h"
+#include "metasurf.h"
+#include "vmath/vmath.h"
+
+struct MetaBall {
+	Vector3 pos;
+	float orbit;
+	float energy;
+	float phase_offs;
+};
+
+#define VOL_SZ			2
+#define MBALL_GRID_SZ	50
+
+static void update();
+static float calc_field(float x, float y, float z);
+static float eval(float x, float y, float z);
+static void vertex(float x, float y, float z);
+static void normal(float x, float y, float z);
+
+static float grid[MBALL_GRID_SZ][MBALL_GRID_SZ][MBALL_GRID_SZ];
+static std::vector<MetaBall> balls;
+static struct metasurface *msurf;
+
+bool mball_init()
+{
+	static const float bbmin = -VOL_SZ / 2.0;
+	static const float bbmax = VOL_SZ / 2.0;
+
+	if(!(msurf = msurf_create())) {
+		return false;
+	}
+	msurf_threshold(msurf, 10);
+	msurf_resolution(msurf, MBALL_GRID_SZ, MBALL_GRID_SZ, MBALL_GRID_SZ);
+	msurf_bounds(msurf, bbmin, bbmin, bbmin, bbmax, bbmax, bbmax);
+	msurf_eval_func(msurf, eval);
+	msurf_vertex_func(msurf, vertex);
+	//msurf_normal_func(msurf, normal);
+
+	for(int i=0; i<10; i++) {
+		MetaBall mb;
+		mb.orbit = 0.25 * rand() / (float)RAND_MAX + 0.35;
+		mb.energy = 0.2 * rand() / (float)RAND_MAX + 0.15;
+		mb.phase_offs = rand() / (float)RAND_MAX * M_PI * 2.0;
+		balls.push_back(mb);
+	}
+
+	return true;
+}
+
+void mball_render()
+{
+	update();
+
+	glMatrixMode(GL_MODELVIEW);
+	glPushMatrix();
+	glScalef(4.0, 4.0, 4.0);
+
+	glBegin(GL_TRIANGLES);
+	msurf_polygonize(msurf);
+	glEnd();
+
+	glPopMatrix();
+}
+
+
+static void update()
+{
+	unsigned int msec = glutGet(GLUT_ELAPSED_TIME);
+	float sec = msec / 1000.0;
+
+	for(size_t i=0; i<balls.size(); i++) {
+		float t = sec + balls[i].phase_offs;
+		balls[i].pos.x = cos(t * 1.8) * balls[i].orbit;
+		balls[i].pos.z = sin(t * 1.2) * balls[i].orbit;
+		balls[i].pos.y = (sin(t) + cos(t * 2.0) / 2.0 + sin(t * 3.0) / 3.0) * 0.45;
+	}
+
+	for(int i=0; i<MBALL_GRID_SZ; i++) {
+		float x = (float)i / (float)MBALL_GRID_SZ * 2.0 - 1.0;
+		for(int j=0; j<MBALL_GRID_SZ; j++) {
+			float y = (float)j / (float)MBALL_GRID_SZ * 2.0 - 1.0;
+			for(int k=0; k<MBALL_GRID_SZ; k++) {
+				float z = (float)k / (float)MBALL_GRID_SZ * 2.0 - 1.0;
+				grid[i][j][k] = calc_field(x, y, z);
+			}
+		}
+	}
+}
+
+static float calc_field(float x, float y, float z)
+{
+	Vector3 pt(x, y, z);
+
+	float sum = 0.0f;
+	for(size_t i=0; i<balls.size(); i++) {
+		float dist_sq = (balls[i].pos - pt).length_sq();
+		if(dist_sq > 1e-6) {
+			sum += balls[i].energy / dist_sq;
+		} else {
+			sum += 1000.0;
+		}
+	}
+	return sum;
+}
+
+static inline int clamp(int x, int a, int b)
+{
+	return x < a ? a : (x > b ? b : x);
+}
+
+static float eval(float x, float y, float z)
+{
+	int cell_x = clamp((int)((x / VOL_SZ + 0.5) * MBALL_GRID_SZ), 0, MBALL_GRID_SZ - 1);
+	int cell_y = clamp((int)((y / VOL_SZ + 0.5) * MBALL_GRID_SZ), 0, MBALL_GRID_SZ - 1);
+	int cell_z = clamp((int)((z / VOL_SZ + 0.5) * MBALL_GRID_SZ), 0, MBALL_GRID_SZ - 1);
+
+	return grid[cell_x][cell_y][cell_z];
+}
+
+static void vertex(float x, float y, float z)
+{
+	float delta = (float)VOL_SZ / (float)MBALL_GRID_SZ;
+
+	float dfdx = calc_field(x - delta, y, z) - calc_field(x + delta, y, z);
+	float dfdy = calc_field(x, y - delta, z) - calc_field(x, y + delta, z);
+	float dfdz = calc_field(x, y, z - delta) - calc_field(x, y, z + delta);
+
+	float len = sqrt(dfdx * dfdx + dfdy * dfdy + dfdz * dfdz);
+
+	glNormal3f(dfdx / len, dfdy / len, dfdz / len);
+	glVertex3f(x, y, z);
+}
+
+static void normal(float x, float y, float z)
+{
+	glNormal3f(x, y, z);
+}
diff -r 5fb21401b7c8 -r e09cbb2e9d4f src/mballs.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mballs.h	Mon Feb 18 03:46:52 2013 +0200
@@ -0,0 +1,7 @@
+#ifndef MBALLS_H_
+#define MBALLS_H_
+
+bool mball_init();
+void mball_render();
+
+#endif	/* MBALLS_H_ */
diff -r 5fb21401b7c8 -r e09cbb2e9d4f src/udg.cc
--- a/src/udg.cc	Thu Feb 07 18:52:28 2013 +0200
+++ b/src/udg.cc	Mon Feb 18 03:46:52 2013 +0200
@@ -6,6 +6,7 @@
 #include "sdr.h"
 #include "dither_matrix.h"
 #include "scroller.h"
+#include "mballs.h"
 
 #define DITHER_SZ		8
 #define DITHER_LEVELS	16
@@ -35,11 +36,14 @@
 void destroy_rtarg(struct render_target *rt);
 
 int xsz, ysz;
-float cam_theta, cam_phi = 25, cam_dist = 8;
+float cam_theta, cam_phi = 25, cam_dist = 9;
 unsigned int dither_tex;
 struct render_target *rtarg;
 unsigned int prog;
 
+int opt_highres, opt_regular_render;
+
+
 int main(int argc, char **argv)
 {
 	glutInit(&argc, argv);
@@ -96,10 +100,15 @@
 		return false;
 	}
 
+	if(!mball_init()) {
+		return false;
+	}
+
 	glEnable(GL_CULL_FACE);
 	glEnable(GL_DEPTH_TEST);
 	glEnable(GL_LIGHTING);
 	glEnable(GL_LIGHT0);
+	glEnable(GL_NORMALIZE);
 
 	return true;
 }
@@ -137,11 +146,15 @@
 void disp()
 {
 	float ldir[] = {-1, 1, 2, 0};
+	int xres, yres;
 
-	int xres = xsz / DITHER_SZ;
-	int yres = ysz / DITHER_SZ;
-	/*int xres = xsz;
-	int yres = ysz;*/
+	if(opt_highres) {
+		xres = xsz;
+		yres = ysz;
+	} else {
+		xres = xsz / DITHER_SZ;
+		yres = ysz / DITHER_SZ;
+	}
 
 	if(!rtarg) {
 		printf("(re)creating render target (%dx%d)\n", xres, yres);
@@ -150,7 +163,9 @@
 		}
 	}
 
-	glBindFramebufferEXT(GL_FRAMEBUFFER, rtarg->fbo);
+	if(!opt_regular_render) {
+		glBindFramebufferEXT(GL_FRAMEBUFFER, rtarg->fbo);
+	}
 	glViewport(0, 0, xres, yres);
 
 	glClearColor(1, 1, 1, 1);
@@ -161,72 +176,72 @@
 	glMatrixMode(GL_MODELVIEW);
 	glLoadIdentity();
 
-	glLightfv(GL_LIGHT0, GL_POSITION, ldir);
-
 	glTranslatef(0, 0, -cam_dist);
 	glRotatef(cam_phi, 1, 0, 0);
 	glRotatef(cam_theta, 0, 1, 0);
 
+	glLightfv(GL_LIGHT0, GL_POSITION, ldir);
+
 	const float blue[] = {0.4, 0.45, 1.0, 1};
 	const float white[] = {1, 1, 1, 1};
 	glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue);
 	glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, white);
 	glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 80.0);
 
-	glFrontFace(GL_CW);
-	glutSolidTeapot(1.0);
-	glFrontFace(GL_CCW);
+	mball_render();
 
 
-	glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
-	glViewport(0, 0, xsz, ysz);
+	if(!opt_regular_render) {
+		glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
+		glViewport(0, 0, xsz, ysz);
 
-	glClear(GL_COLOR_BUFFER_BIT);
+		glClear(GL_COLOR_BUFFER_BIT);
 
-	glMatrixMode(GL_PROJECTION);
-	glPushMatrix();
-	glLoadIdentity();
-	glMatrixMode(GL_MODELVIEW);
-	glLoadIdentity();
-	glPushMatrix();
+		glMatrixMode(GL_PROJECTION);
+		glPushMatrix();
+		glLoadIdentity();
+		glMatrixMode(GL_MODELVIEW);
+		glLoadIdentity();
+		glPushMatrix();
 
-	glPushAttrib(GL_ENABLE_BIT);
-	glDisable(GL_DEPTH_TEST);
+		glPushAttrib(GL_ENABLE_BIT);
+		glDisable(GL_DEPTH_TEST);
 
-	bind_program(prog);
-	set_uniform_int(prog, "framebuf", 0);
-	set_uniform_int(prog, "dither_tex", 1);
-	set_uniform_int(prog, "dither_levels", DITHER_LEVELS);
-	set_uniform_int(prog, "dither_size", DITHER_SZ);
+		bind_program(prog);
+		set_uniform_int(prog, "framebuf", 0);
+		set_uniform_int(prog, "dither_tex", 1);
+		set_uniform_int(prog, "dither_levels", DITHER_LEVELS);
+		set_uniform_int(prog, "dither_size", DITHER_SZ);
 
-	glActiveTextureARB(GL_TEXTURE0);
-	glBindTexture(GL_TEXTURE_2D, rtarg->color_tex);
-	glEnable(GL_TEXTURE_2D);
-	glActiveTextureARB(GL_TEXTURE1);
-	glBindTexture(GL_TEXTURE_2D, dither_tex);
-	glEnable(GL_TEXTURE_2D);
+		glActiveTextureARB(GL_TEXTURE0);
+		glBindTexture(GL_TEXTURE_2D, rtarg->color_tex);
+		glEnable(GL_TEXTURE_2D);
+		glActiveTextureARB(GL_TEXTURE1);
+		glBindTexture(GL_TEXTURE_2D, dither_tex);
+		glEnable(GL_TEXTURE_2D);
 
-	glBegin(GL_QUADS);
-	glColor3f(0, 1, 0);
-	glTexCoord2f(0, 0); glVertex2f(-1, -1);
-	glTexCoord2f(1, 0); glVertex2f(1, -1);
-	glTexCoord2f(1, 1); glVertex2f(1, 1);
-	glTexCoord2f(0, 1); glVertex2f(-1, 1);
-	glEnd();
+		glBegin(GL_QUADS);
+		glColor3f(0, 1, 0);
+		glTexCoord2f(0, 0); glVertex2f(-1, -1);
+		glTexCoord2f(1, 0); glVertex2f(1, -1);
+		glTexCoord2f(1, 1); glVertex2f(1, 1);
+		glTexCoord2f(0, 1); glVertex2f(-1, 1);
+		glEnd();
 
-	glActiveTextureARB(GL_TEXTURE1);
-	glDisable(GL_TEXTURE_2D);
-	glActiveTextureARB(GL_TEXTURE0);
-	glDisable(GL_TEXTURE_2D);
+		glActiveTextureARB(GL_TEXTURE1);
+		glDisable(GL_TEXTURE_2D);
+		glActiveTextureARB(GL_TEXTURE0);
+		glDisable(GL_TEXTURE_2D);
 
-	bind_program(0);
+		bind_program(0);
 
-	glPopAttrib();
+		glPopAttrib();
 
-	glMatrixMode(GL_PROJECTION);
-	glPopMatrix();
-	glMatrixMode(GL_MODELVIEW);
-	glPopMatrix();
+		glMatrixMode(GL_PROJECTION);
+		glPopMatrix();
+		glMatrixMode(GL_MODELVIEW);
+		glPopMatrix();
+	}
 
 	glutSwapBuffers();
 	assert(glGetError() == GL_NO_ERROR);
@@ -274,6 +289,18 @@
 			}
 		}
 		break;
+
+	case 'r':
+		opt_regular_render = !opt_regular_render;
+		break;
+
+	case 'h':
+		opt_highres = !opt_highres;
+		if(rtarg) {
+			destroy_rtarg(rtarg);
+			rtarg = 0;
+		}
+		break;
 	}
 }