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-rw-r--r--hacks/glx/marching.c645
1 files changed, 645 insertions, 0 deletions
diff --git a/hacks/glx/marching.c b/hacks/glx/marching.c
new file mode 100644
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+++ b/hacks/glx/marching.c
@@ -0,0 +1,645 @@
+/* xscreensaver, Copyright (c) 2002 Jamie Zawinski <jwz@jwz.org>
+ * Utility functions to create "marching cubes" meshes from 3d fields.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation. No representations are made about the suitability of this
+ * software for any purpose. It is provided "as is" without express or
+ * implied warranty.
+ *
+ * Marching cubes implementation by Paul Bourke <pbourke@swin.edu.au>
+ * http://astronomy.swin.edu.au/~pbourke/modelling/polygonise/
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+
+#ifndef HAVE_JWXYZ
+# include <GL/gl.h>
+#endif
+
+#ifdef HAVE_ANDROID
+# include <GLES/gl.h>
+#endif
+
+#ifdef HAVE_JWZGLES
+# include "jwzgles.h"
+#endif /* HAVE_JWZGLES */
+
+#include "marching.h"
+#include "normals.h"
+
+extern char *progname;
+
+#undef ABS
+#define ABS(x) ((x)<0?(-(x)):(x))
+
+typedef struct {
+ XYZ p[3];
+} TRIANGLE;
+
+typedef struct {
+ XYZ p[8];
+ double val[8];
+} GRIDCELL;
+
+
+/* Indexing convention:
+
+ Vertices: Edges:
+
+ 4 ______________ 5 ______________
+ /| /| /| 4 /|
+ / | 6 / | 7 / |8 5 / |
+ 7 /_____________/ | /______________/ | 9
+ | | | | | | 6 | |
+ | 0 |_________|___| 1 | |_________|10_|
+ | / | / 11 | 3/ 0 | /
+ | / | / | / | / 1
+ 3 |/____________|/ 2 |/____________|/
+ 2
+ */
+
+static const int edgeTable[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 const int triTable[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}
+};
+
+
+
+/* Linearly interpolate the position where an isosurface cuts
+ an edge between two vertices, each with their own scalar value
+*/
+static XYZ
+interp_vertex (double isolevel, XYZ p1, XYZ p2, double valp1, double valp2)
+{
+ double mu;
+ XYZ p;
+
+ if (ABS(isolevel-valp1) < 0.00001)
+ return(p1);
+ if (ABS(isolevel-valp2) < 0.00001)
+ return(p2);
+ if (ABS(valp1-valp2) < 0.00001)
+ return(p1);
+ mu = (isolevel - valp1) / (valp2 - valp1);
+ p.x = p1.x + mu * (p2.x - p1.x);
+ p.y = p1.y + mu * (p2.y - p1.y);
+ p.z = p1.z + mu * (p2.z - p1.z);
+
+ return(p);
+}
+
+
+/* Given a grid cell and an isolevel, calculate the triangular
+ facets required to represent the isosurface through the cell.
+ Return the number of triangular facets.
+ `triangles' will be loaded up with the vertices at most 5 triangular facets.
+ 0 will be returned if the grid cell is either totally above
+ of totally below the isolevel.
+
+ By Paul Bourke <pbourke@swin.edu.au>
+*/
+static int
+march_one_cube (GRIDCELL grid, double isolevel, TRIANGLE *triangles)
+{
+ int i, ntriang;
+ int cubeindex;
+ XYZ vertlist[12];
+
+ /*
+ Determine the index into the edge table which
+ tells us which vertices are inside of the surface
+ */
+ cubeindex = 0;
+ if (grid.val[0] < isolevel) cubeindex |= 1;
+ if (grid.val[1] < isolevel) cubeindex |= 2;
+ if (grid.val[2] < isolevel) cubeindex |= 4;
+ if (grid.val[3] < isolevel) cubeindex |= 8;
+ if (grid.val[4] < isolevel) cubeindex |= 16;
+ if (grid.val[5] < isolevel) cubeindex |= 32;
+ if (grid.val[6] < isolevel) cubeindex |= 64;
+ if (grid.val[7] < isolevel) cubeindex |= 128;
+
+ /* Cube is entirely in/out of the surface */
+ if (edgeTable[cubeindex] == 0)
+ return(0);
+
+ /* Find the vertices where the surface intersects the cube */
+ if (edgeTable[cubeindex] & 1)
+ vertlist[0] =
+ interp_vertex (isolevel,grid.p[0],grid.p[1],grid.val[0],grid.val[1]);
+ if (edgeTable[cubeindex] & 2)
+ vertlist[1] =
+ interp_vertex (isolevel,grid.p[1],grid.p[2],grid.val[1],grid.val[2]);
+ if (edgeTable[cubeindex] & 4)
+ vertlist[2] =
+ interp_vertex (isolevel,grid.p[2],grid.p[3],grid.val[2],grid.val[3]);
+ if (edgeTable[cubeindex] & 8)
+ vertlist[3] =
+ interp_vertex (isolevel,grid.p[3],grid.p[0],grid.val[3],grid.val[0]);
+ if (edgeTable[cubeindex] & 16)
+ vertlist[4] =
+ interp_vertex (isolevel,grid.p[4],grid.p[5],grid.val[4],grid.val[5]);
+ if (edgeTable[cubeindex] & 32)
+ vertlist[5] =
+ interp_vertex (isolevel,grid.p[5],grid.p[6],grid.val[5],grid.val[6]);
+ if (edgeTable[cubeindex] & 64)
+ vertlist[6] =
+ interp_vertex (isolevel,grid.p[6],grid.p[7],grid.val[6],grid.val[7]);
+ if (edgeTable[cubeindex] & 128)
+ vertlist[7] =
+ interp_vertex (isolevel,grid.p[7],grid.p[4],grid.val[7],grid.val[4]);
+ if (edgeTable[cubeindex] & 256)
+ vertlist[8] =
+ interp_vertex (isolevel,grid.p[0],grid.p[4],grid.val[0],grid.val[4]);
+ if (edgeTable[cubeindex] & 512)
+ vertlist[9] =
+ interp_vertex (isolevel,grid.p[1],grid.p[5],grid.val[1],grid.val[5]);
+ if (edgeTable[cubeindex] & 1024)
+ vertlist[10] =
+ interp_vertex (isolevel,grid.p[2],grid.p[6],grid.val[2],grid.val[6]);
+ if (edgeTable[cubeindex] & 2048)
+ vertlist[11] =
+ interp_vertex (isolevel,grid.p[3],grid.p[7],grid.val[3],grid.val[7]);
+
+ /* Create the triangle */
+ ntriang = 0;
+ for (i=0; triTable[cubeindex][i] != -1; i+=3)
+ {
+ triangles[ntriang].p[0] = vertlist[triTable[cubeindex][i ]];
+ triangles[ntriang].p[1] = vertlist[triTable[cubeindex][i+1]];
+ triangles[ntriang].p[2] = vertlist[triTable[cubeindex][i+2]];
+ ntriang++;
+ }
+
+ return(ntriang);
+}
+
+
+/* Walking the grid. By jwz.
+ */
+
+
+/* Computes the normal of the scalar field at the given point,
+ for vertex normals (as opposed to face normals.)
+ */
+static void
+do_function_normal (double x, double y, double z,
+ double (*compute_fn) (double x, double y, double z,
+ void *closure),
+ void *c)
+{
+ XYZ n;
+ double off = 0.5;
+ n.x = compute_fn (x-off, y, z, c) - compute_fn (x+off, y, z, c);
+ n.y = compute_fn (x, y-off, z, c) - compute_fn (x, y+off, z, c);
+ n.z = compute_fn (x, y, z-off, c) - compute_fn (x, y, z+off, c);
+ /* normalize (&n); */
+ glNormal3f (n.x, n.y, n.z);
+}
+
+
+/* Given a function capable of generating a value at any XYZ position,
+ creates OpenGL faces for the solids defined.
+
+ init_fn is called at the beginning for initial, and returns an object.
+ free_fn is called at the end.
+
+ compute_fn is called for each XYZ in the specified grid, and returns
+ the double value of that coordinate. If smoothing is on, then
+ compute_fn will also be called twice more for each emitted vertex,
+ in order to calculate vertex normals (so don't assume it will only
+ be called with values falling on the grid boundaries.)
+
+ Points are inside an object if the are less than `isolevel', and
+ outside otherwise.
+*/
+void
+marching_cubes (int grid_size, /* density of the mesh */
+ double isolevel, /* cutoff point for "in" versus "out" */
+ int wireframe_p, /* wireframe, or solid */
+ int smooth_p, /* smooth, or faceted */
+
+ void * (*init_fn) (double grid_size, void *closure1),
+ double (*compute_fn) (double x, double y, double z,
+ void *closure2),
+ void (*free_fn) (void *closure2),
+ void *closure1,
+
+ unsigned long *polygon_count)
+{
+ int planesize = grid_size * grid_size;
+ int x, y, z;
+ void *closure2 = 0;
+ unsigned long polys = 0;
+ double *layers;
+
+ layers = (double *) calloc (sizeof (*layers), planesize * 2);
+ if (!layers)
+ {
+ fprintf (stderr, "%s: out of memory for %dx%dx%d grid\n",
+ progname, grid_size, grid_size, 2);
+ exit (1);
+ }
+
+ if (init_fn)
+ closure2 = init_fn (grid_size, closure1);
+
+ glFrontFace(GL_CCW);
+ if (!wireframe_p)
+ glBegin (GL_TRIANGLES);
+
+ for (z = 0; z < grid_size; z++)
+ {
+ double *layer0 = (z & 1 ? layers+planesize : layers);
+ double *layer1 = (z & 1 ? layers : layers+planesize);
+ double *row;
+
+ /* Fill in the XY grid on the currently-bottommost layer. */
+ row = layer1;
+ for (y = 0; y < grid_size; y++, row += grid_size)
+ {
+ double *cell = row;
+ for (x = 0; x < grid_size; x++, cell++)
+ *cell = compute_fn (x, y, z, closure2);
+ }
+
+ /* Now we've completed one layer (an XY slice of Z.) Now we can
+ generate the polygons that fill the space between this layer
+ and the previous one (unless this is the first layer.)
+ */
+ if (z == 0) continue;
+
+ for (y = 1; y < grid_size; y += 1)
+ for (x = 1; x < grid_size; x += 1)
+ {
+ TRIANGLE tri[6];
+ int i, ntri;
+ GRIDCELL cell;
+
+ /* This is kinda hokey, there ought to be a more efficient
+ way to do this... */
+ cell.p[0].x = x-1; cell.p[0].y = y-1; cell.p[0].z = z-1;
+ cell.p[1].x = x ; cell.p[1].y = y-1; cell.p[1].z = z-1;
+ cell.p[2].x = x ; cell.p[2].y = y ; cell.p[2].z = z-1;
+ cell.p[3].x = x-1; cell.p[3].y = y ; cell.p[3].z = z-1;
+ cell.p[4].x = x-1; cell.p[4].y = y-1; cell.p[4].z = z ;
+ cell.p[5].x = x ; cell.p[5].y = y-1; cell.p[5].z = z ;
+ cell.p[6].x = x ; cell.p[6].y = y ; cell.p[6].z = z ;
+ cell.p[7].x = x-1; cell.p[7].y = y ; cell.p[7].z = z ;
+
+# define GRID(X,Y,WHICH) ((WHICH) \
+ ? layer1[((Y)*grid_size) + ((X))] \
+ : layer0[((Y)*grid_size) + ((X))])
+
+ cell.val[0] = GRID (x-1, y-1, 0);
+ cell.val[1] = GRID (x , y-1, 0);
+ cell.val[2] = GRID (x , y , 0);
+ cell.val[3] = GRID (x-1, y , 0);
+ cell.val[4] = GRID (x-1, y-1, 1);
+ cell.val[5] = GRID (x , y-1, 1);
+ cell.val[6] = GRID (x , y , 1);
+ cell.val[7] = GRID (x-1, y , 1);
+# undef GRID
+
+ /* Now generate the triangles for this cubic segment,
+ and emit the GL faces.
+ */
+ ntri = march_one_cube (cell, isolevel, tri);
+ polys += ntri;
+ for (i = 0; i < ntri; i++)
+ {
+ if (wireframe_p) glBegin (GL_LINE_LOOP);
+
+ /* If we're smoothing, we need to call the field function
+ again for each vertex (via function_normal().) If we're
+ not smoothing, then we can just compute the normal from
+ this triangle.
+ */
+ if (!smooth_p)
+ do_normal (tri[i].p[0].x, tri[i].p[0].y, tri[i].p[0].z,
+ tri[i].p[1].x, tri[i].p[1].y, tri[i].p[1].z,
+ tri[i].p[2].x, tri[i].p[2].y, tri[i].p[2].z);
+
+# define VERT(X,Y,Z) \
+ if (smooth_p) \
+ do_function_normal ((X), (Y), (Z), compute_fn, closure2); \
+ glVertex3f ((X), (Y), (Z))
+
+ VERT (tri[i].p[0].x, tri[i].p[0].y, tri[i].p[0].z);
+ VERT (tri[i].p[1].x, tri[i].p[1].y, tri[i].p[1].z);
+ VERT (tri[i].p[2].x, tri[i].p[2].y, tri[i].p[2].z);
+# undef VERT
+ if (wireframe_p) glEnd ();
+ }
+ }
+ }
+
+ if (!wireframe_p)
+ glEnd ();
+
+ free (layers);
+
+ if (free_fn)
+ free_fn (closure2);
+
+ if (polygon_count)
+ *polygon_count = polys;
+}