[37] | 1 | /* |
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| 2 | |
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| 3 | Converts from Paul Ning's polygon file format to text polygon description. |
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| 4 | |
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| 5 | Greg Turk - November 1992 |
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| 6 | |
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| 7 | */ |
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| 8 | |
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| 9 | #include <stdio.h> |
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| 10 | #include <malloc.h> |
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| 11 | #include "mcfile.h" |
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| 12 | #include <math.h> |
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| 13 | #include <string.h> |
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| 14 | #include <unistd.h> |
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| 15 | |
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| 16 | #include "Linear.h" |
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| 17 | |
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| 18 | #include "ply.h" |
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| 19 | |
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| 20 | struct PlyVertex { |
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| 21 | float x, y, z; |
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| 22 | float nx, ny, nz; |
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| 23 | }; |
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| 24 | |
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| 25 | struct PlyFace { |
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| 26 | unsigned char nverts; |
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| 27 | int *verts; |
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| 28 | }; |
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| 29 | |
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| 30 | static PlyVertex *vert_dummy; |
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| 31 | #define voffset(field) ((char *) (&vert_dummy->field) - (char *) vert_dummy) |
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| 32 | |
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| 33 | static PlyFace *face_dummy; |
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| 34 | #define foffset(field) ((char *) (&face_dummy->field) - (char *) face_dummy) |
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| 35 | |
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| 36 | static char *elem_names[] = { |
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| 37 | "vertex", "face", |
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| 38 | }; |
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| 39 | |
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| 40 | static PlyProperty vert_props[] = { |
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| 41 | {"x", PLY_FLOAT, PLY_FLOAT, 0, 0, PLY_START_TYPE, PLY_START_TYPE, 0}, |
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| 42 | {"y", PLY_FLOAT, PLY_FLOAT, 0, 0, PLY_START_TYPE, PLY_START_TYPE, 0}, |
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| 43 | {"z", PLY_FLOAT, PLY_FLOAT, 0, 0, PLY_START_TYPE, PLY_START_TYPE, 0}, |
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| 44 | {"nx", PLY_FLOAT, PLY_FLOAT, 0, 0, PLY_START_TYPE, PLY_START_TYPE, 0}, |
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| 45 | {"ny", PLY_FLOAT, PLY_FLOAT, 0, 0, PLY_START_TYPE, PLY_START_TYPE, 0}, |
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| 46 | {"nz", PLY_FLOAT, PLY_FLOAT, 0, 0, PLY_START_TYPE, PLY_START_TYPE, 0} |
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| 47 | }; |
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| 48 | |
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| 49 | static PlyProperty face_props[] = { |
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| 50 | {"vertex_indices", PLY_INT, PLY_INT, 0, 1, PLY_UCHAR, PLY_UCHAR, 0}, |
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| 51 | }; |
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| 52 | |
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| 53 | |
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| 54 | TriangleVertex *verts; |
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| 55 | int npolys; |
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| 56 | |
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| 57 | |
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| 58 | void write_polys_ply(char *filename); |
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| 59 | |
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| 60 | |
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| 61 | /****************************************************************************** |
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| 62 | Main routine. |
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| 63 | ******************************************************************************/ |
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| 64 | |
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| 65 | void |
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| 66 | main(int, char **argv) |
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| 67 | { |
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| 68 | int i,j; |
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| 69 | FILE *fp; |
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| 70 | char infile[80],outfile[80]; |
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| 71 | mcfile header; |
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| 72 | int index; |
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| 73 | |
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| 74 | strcpy (infile, argv[1]); |
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| 75 | strcpy (outfile, argv[2]); |
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| 76 | |
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| 77 | if (strlen (infile) < 3 || |
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| 78 | strcmp (infile + strlen (infile) - 3, ".mc") != 0) |
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| 79 | strcat (infile, ".mc"); |
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| 80 | |
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| 81 | if (strlen (outfile) < 5 || |
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| 82 | strcmp (outfile + strlen (outfile) - 5, ".ply") != 0) |
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| 83 | strcat (outfile, ".ply"); |
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| 84 | |
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| 85 | printf ("reading polygons from '%s'\n", infile); |
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| 86 | |
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| 87 | /* open the polygon input file */ |
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| 88 | |
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| 89 | if ((fp = fopen(infile, "r")) == NULL) { |
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| 90 | fprintf (stderr, "bad open\n"); |
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| 91 | exit (-1); |
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| 92 | } |
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| 93 | |
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| 94 | /* open the polygon output file */ |
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| 95 | |
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| 96 | /* |
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| 97 | if ((fp_out = fopen(outfile, "w+b")) == NULL) { |
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| 98 | fprintf (stderr, "bad open\n"); |
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| 99 | exit (-1); |
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| 100 | } |
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| 101 | */ |
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| 102 | |
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| 103 | /* read header info from the polygon file */ |
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| 104 | header = MC_ReadHeader (fp); |
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| 105 | |
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| 106 | /* |
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| 107 | npolys = header.mc_length / (3 * sizeof (sizeof(TriangleVertex))); |
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| 108 | */ |
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| 109 | npolys = header.mc_length / 42; |
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| 110 | printf ("%d polygons\n", npolys); |
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| 111 | verts = (TriangleVertex *) malloc (sizeof (TriangleVertex) * 3 * npolys); |
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| 112 | if (verts == 0) { |
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| 113 | fprintf (stderr, "can't allocate enough space\n"); |
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| 114 | exit (-1); |
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| 115 | } |
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| 116 | |
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| 117 | /* read in the polygons */ |
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| 118 | printf ("reading polygons...\n"); |
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| 119 | for (i = 0; i < npolys; i++) { |
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| 120 | for (j = 0; j < 3; j++) { |
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| 121 | index = i * 3 + j; |
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| 122 | verts[index] = MC_ReadTriangleVertex (fp); |
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| 123 | } |
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| 124 | } |
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| 125 | |
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| 126 | /* write polygons to output file */ |
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| 127 | printf ("writing polygons...\n"); |
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| 128 | write_polys_ply (outfile); |
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| 129 | |
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| 130 | printf ("done.\n"); |
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| 131 | } |
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| 132 | |
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| 133 | |
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| 134 | /****************************************************************************** |
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| 135 | Write out polygons in Inventor format. |
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| 136 | ******************************************************************************/ |
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| 137 | |
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| 138 | void |
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| 139 | write_polys_ply(char *filename) |
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| 140 | { |
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| 141 | int i,j; |
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| 142 | int index; |
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| 143 | float len; |
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| 144 | float version; |
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| 145 | |
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| 146 | PlyFile *ply = ply_open_for_writing(filename, 2, elem_names, |
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| 147 | PLY_BINARY_BE, &version); |
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| 148 | |
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| 149 | |
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| 150 | // Shouldn't this be a tri-strip-set??? |
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| 151 | int numVerts = 3*npolys; // Hugely inefficient!! |
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| 152 | int numFaces = npolys; |
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| 153 | |
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| 154 | int nvp = 0; |
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| 155 | vert_props[nvp].offset = voffset(x); nvp++; |
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| 156 | vert_props[nvp].offset = voffset(y); nvp++; |
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| 157 | vert_props[nvp].offset = voffset(z); nvp++; |
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| 158 | |
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| 159 | vert_props[nvp].offset = voffset(nx); nvp++; |
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| 160 | vert_props[nvp].offset = voffset(ny); nvp++; |
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| 161 | vert_props[nvp].offset = voffset(nz); nvp++; |
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| 162 | |
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| 163 | |
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| 164 | face_props[0].offset = foffset(verts); |
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| 165 | face_props[0].count_offset = foffset(nverts); /* count offset */ |
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| 166 | |
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| 167 | ply_describe_element (ply, "vertex", numVerts, |
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| 168 | nvp, vert_props); |
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| 169 | |
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| 170 | ply_describe_element (ply, "face", npolys, 1, face_props); |
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| 171 | |
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| 172 | ply_header_complete (ply); |
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| 173 | |
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| 174 | /* set up and write the vertex elements */ |
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| 175 | PlyVertex vert; |
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| 176 | ply_put_element_setup (ply, "vertex"); |
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| 177 | for (i = 0; i < npolys; i++) { |
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| 178 | for (j = 0; j < 3; j++) { |
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| 179 | index = i * 3 + j; |
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| 180 | vert.x = verts[index].x / 128.0; |
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| 181 | vert.y = verts[index].y / 128.0; |
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| 182 | vert. z = verts[index].z / 128.0; |
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| 183 | vert.nx = -verts[index].nx; |
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| 184 | vert.ny = -verts[index].ny; |
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| 185 | vert.nz = -verts[index].nz; |
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| 186 | len = sqrt (vert.nx*vert.nx + vert.ny*vert.ny + vert.nz*vert.nz); |
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| 187 | vert.nx /= len; |
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| 188 | vert.ny /= len; |
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| 189 | vert.nz /= len; |
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| 190 | ply_put_element (ply, (void *) &vert); |
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| 191 | } |
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| 192 | } |
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| 193 | |
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| 194 | /* set up and write the face elements */ |
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| 195 | PlyFace face; |
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| 196 | int v[3]; |
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| 197 | face.nverts = 3; |
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| 198 | face.verts = (int *)(v); |
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| 199 | ply_put_element_setup (ply, "face"); |
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| 200 | for (i = 0; i < npolys; i++) { |
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| 201 | Vec3f v1(verts[i*3].x, verts[i*3].y, verts[i*3].z); |
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| 202 | Vec3f v2(verts[i*3+1].x, verts[i*3+1].y, verts[i*3+1].z); |
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| 203 | Vec3f v3(verts[i*3+2].x, verts[i*3+2].y, verts[i*3+2].z); |
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| 204 | |
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| 205 | Vec3f a = v2 - v1; |
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| 206 | Vec3f b = v3 - v1; |
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| 207 | Vec3f c = a.cross(b); |
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| 208 | Vec3f norm(-verts[i*3].nx, -verts[i*3].ny, -verts[i*3].nz); |
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| 209 | if (c.dot(norm) > 0) { |
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| 210 | face.verts[0] = i*3; |
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| 211 | face.verts[1] = i*3+1; |
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| 212 | face.verts[2] = i*3+2; |
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| 213 | } |
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| 214 | else { |
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| 215 | face.verts[0] = i*3+1; |
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| 216 | face.verts[1] = i*3; |
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| 217 | face.verts[2] = i*3+2; |
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| 218 | } |
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| 219 | ply_put_element (ply, (void *) &face); |
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| 220 | } |
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| 221 | |
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| 222 | /* close the PLY file */ |
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| 223 | ply_close (ply); |
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| 224 | } |
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| 225 | |
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