[37] | 1 | /* |
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| 2 | |
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| 3 | plyplanecrop: |
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| 4 | crop away all points in a ply file below a specified plane. |
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| 5 | |
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| 6 | Brian Curless, 2005. |
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| 7 | |
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| 8 | */ |
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| 9 | |
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| 10 | #include <stdio.h> |
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| 11 | #include <stdlib.h> |
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| 12 | #include <math.h> |
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| 13 | #include <strings.h> |
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| 14 | #include <ply.h> |
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| 15 | |
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| 16 | float A,B,C,D; |
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| 17 | |
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| 18 | /* user's vertex and face definitions for a polygonal object */ |
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| 19 | |
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| 20 | typedef struct Vertex { |
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| 21 | float x,y,z; |
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| 22 | int index; |
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| 23 | void *other_props; /* other properties */ |
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| 24 | } Vertex; |
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| 25 | |
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| 26 | typedef struct Face { |
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| 27 | unsigned char nverts; /* number of vertex indices in list */ |
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| 28 | int *verts; /* vertex index list */ |
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| 29 | void *other_props; /* other properties */ |
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| 30 | } Face; |
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| 31 | |
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| 32 | char *elem_names[] = { /* list of the kinds of elements in the user's object */ |
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| 33 | "vertex", "face" |
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| 34 | }; |
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| 35 | |
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| 36 | PlyProperty vert_props[] = { /* list of property information for a vertex */ |
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| 37 | {"x", PLY_FLOAT, PLY_FLOAT, offsetof(Vertex,x), 0, 0, 0, 0}, |
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| 38 | {"y", PLY_FLOAT, PLY_FLOAT, offsetof(Vertex,y), 0, 0, 0, 0}, |
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| 39 | {"z", PLY_FLOAT, PLY_FLOAT, offsetof(Vertex,z), 0, 0, 0, 0}, |
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| 40 | }; |
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| 41 | |
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| 42 | PlyProperty face_props[] = { /* list of property information for a vertex */ |
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| 43 | {"vertex_indices", PLY_INT, PLY_INT, offsetof(Face,verts), |
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| 44 | 1, PLY_UCHAR, PLY_UCHAR, offsetof(Face,nverts)}, |
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| 45 | }; |
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| 46 | |
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| 47 | |
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| 48 | /*** the PLY object ***/ |
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| 49 | |
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| 50 | static int nverts,nfaces; |
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| 51 | static Vertex **vlist; |
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| 52 | static Face **flist; |
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| 53 | static PlyOtherElems *other_elements = NULL; |
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| 54 | static PlyOtherProp *vert_other,*face_other; |
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| 55 | static int nelems; |
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| 56 | static char **elist; |
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| 57 | static int num_comments; |
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| 58 | static char **comments; |
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| 59 | static int num_obj_info; |
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| 60 | static char **obj_info; |
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| 61 | static int file_type; |
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| 62 | |
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| 63 | void usage(char *progname); |
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| 64 | void read_file(FILE *inFile); |
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| 65 | void write_file(); |
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| 66 | |
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| 67 | |
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| 68 | /****************************************************************************** |
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| 69 | Main program. |
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| 70 | ******************************************************************************/ |
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| 71 | |
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| 72 | int |
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| 73 | main(int argc, char *argv[]) |
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| 74 | { |
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| 75 | int i,j; |
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| 76 | char *s; |
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| 77 | char *progname; |
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| 78 | FILE *inFile = stdin; |
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| 79 | |
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| 80 | progname = argv[0]; |
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| 81 | |
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| 82 | if (argc < 5 || argc > 6) { |
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| 83 | usage (progname); |
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| 84 | exit (-1); |
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| 85 | } |
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| 86 | |
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| 87 | A = atof(argv[1]); |
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| 88 | B = atof(argv[2]); |
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| 89 | C = atof(argv[3]); |
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| 90 | D = atof(argv[4]); |
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| 91 | |
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| 92 | /* optional input file (if not, read stdin ) */ |
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| 93 | if (argc == 6) { |
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| 94 | inFile = fopen(argv[5], "r"); |
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| 95 | if (inFile == NULL) { |
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| 96 | fprintf(stderr, "Error: Couldn't open input file %s\n", argv[0]); |
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| 97 | usage(progname); |
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| 98 | exit(-1); |
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| 99 | } |
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| 100 | } |
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| 101 | |
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| 102 | // Read in the file |
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| 103 | read_file(inFile); |
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| 104 | |
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| 105 | // Write back out, ignoring points below the plane |
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| 106 | write_file(); |
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| 107 | } |
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| 108 | |
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| 109 | |
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| 110 | /****************************************************************************** |
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| 111 | Print out usage information. |
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| 112 | ******************************************************************************/ |
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| 113 | |
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| 114 | void |
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| 115 | usage(char *progname) |
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| 116 | { |
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| 117 | fprintf (stderr, "usage: %s <a> <b> <c> <d> [in.ply] > out.ply\n", progname); |
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| 118 | fprintf (stderr, " or: %s <a> <b> <c> <d> < in.ply > out.ply\n", progname); |
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| 119 | fprintf (stderr, "\n"); |
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| 120 | fprintf (stderr, " This program will remove all vertices (and their\n"); |
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| 121 | fprintf (stderr, " corresponding faces) that are outside the specified\n"); |
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| 122 | fprintf (stderr, " plane, i.e., vertices where a*x + b*y + c*z + d < 0.\n"); |
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| 123 | fprintf (stderr, "\n"); |
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| 124 | exit(-1); |
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| 125 | } |
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| 126 | |
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| 127 | |
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| 128 | |
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| 129 | /****************************************************************************** |
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| 130 | Read in the PLY file from standard in. |
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| 131 | ******************************************************************************/ |
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| 132 | |
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| 133 | void |
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| 134 | read_file(FILE *inFile) |
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| 135 | { |
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| 136 | int i,j,k; |
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| 137 | PlyFile *ply; |
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| 138 | int nprops; |
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| 139 | int num_elems; |
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| 140 | PlyProperty **plist; |
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| 141 | char *elem_name; |
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| 142 | float version; |
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| 143 | |
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| 144 | |
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| 145 | /*** Read in the original PLY object ***/ |
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| 146 | |
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| 147 | |
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| 148 | ply = ply_read (inFile, &nelems, &elist); |
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| 149 | ply_get_info (ply, &version, &file_type); |
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| 150 | |
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| 151 | for (i = 0; i < nelems; i++) { |
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| 152 | |
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| 153 | /* get the description of the first element */ |
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| 154 | elem_name = elist[i]; |
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| 155 | plist = ply_get_element_description (ply, elem_name, &num_elems, &nprops); |
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| 156 | |
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| 157 | if (equal_strings ("vertex", elem_name)) { |
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| 158 | |
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| 159 | /* create a vertex list to hold all the vertices */ |
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| 160 | vlist = (Vertex **) malloc (sizeof (Vertex *) * num_elems); |
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| 161 | nverts = num_elems; |
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| 162 | |
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| 163 | /* set up for getting vertex elements */ |
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| 164 | |
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| 165 | ply_get_property (ply, elem_name, &vert_props[0]); |
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| 166 | ply_get_property (ply, elem_name, &vert_props[1]); |
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| 167 | ply_get_property (ply, elem_name, &vert_props[2]); |
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| 168 | vert_other = ply_get_other_properties (ply, elem_name, |
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| 169 | offsetof(Vertex,other_props)); |
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| 170 | |
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| 171 | /* grab all the vertex elements */ |
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| 172 | for (j = 0; j < num_elems; j++) { |
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| 173 | vlist[j] = (Vertex *) malloc (sizeof (Vertex)); |
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| 174 | ply_get_element (ply, (void *) vlist[j]); |
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| 175 | } |
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| 176 | } |
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| 177 | else if (equal_strings ("face", elem_name)) { |
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| 178 | |
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| 179 | /* create a list to hold all the face elements */ |
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| 180 | flist = (Face **) malloc (sizeof (Face *) * num_elems); |
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| 181 | nfaces = num_elems; |
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| 182 | |
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| 183 | /* set up for getting face elements */ |
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| 184 | |
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| 185 | ply_get_property (ply, elem_name, &face_props[0]); |
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| 186 | face_other = ply_get_other_properties (ply, elem_name, |
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| 187 | offsetof(Face,other_props)); |
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| 188 | |
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| 189 | /* grab all the face elements */ |
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| 190 | for (j = 0; j < num_elems; j++) { |
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| 191 | flist[j] = (Face *) malloc (sizeof (Face)); |
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| 192 | ply_get_element (ply, (void *) flist[j]); |
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| 193 | /* DEBUG |
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| 194 | fprintf(stderr, "face %d: %d verts: %d %d %d\n", |
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| 195 | j, flist[j]->nverts, |
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| 196 | flist[j]->verts[0], |
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| 197 | flist[j]->verts[1], |
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| 198 | flist[j]->verts[2]); |
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| 199 | */ |
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| 200 | } |
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| 201 | } |
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| 202 | else |
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| 203 | other_elements = ply_get_other_element (ply, elem_name, num_elems); |
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| 204 | } |
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| 205 | |
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| 206 | comments = ply_get_comments (ply, &num_comments); |
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| 207 | obj_info = ply_get_obj_info (ply, &num_obj_info); |
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| 208 | |
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| 209 | ply_close (ply); |
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| 210 | } |
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| 211 | |
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| 212 | |
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| 213 | /****************************************************************************** |
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| 214 | Write out the PLY file to standard out. |
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| 215 | Ignore all the points (and corresponding faces) below |
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| 216 | the plane. |
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| 217 | ******************************************************************************/ |
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| 218 | |
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| 219 | void |
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| 220 | write_file() |
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| 221 | { |
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| 222 | int i,j,k; |
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| 223 | PlyFile *ply; |
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| 224 | int num_elems; |
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| 225 | char *elem_name; |
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| 226 | int vert_count; |
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| 227 | int face_count; |
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| 228 | |
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| 229 | /*** Write out the final PLY object ***/ |
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| 230 | |
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| 231 | |
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| 232 | ply = ply_write (stdout, nelems, elist, file_type); |
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| 233 | |
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| 234 | // count the vertices that are above the plane |
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| 235 | vert_count = 0; |
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| 236 | for (i = 0; i < nverts; i++) { |
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| 237 | // Set the index to either the index number, or -1... |
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| 238 | if (A*vlist[i]->x + B*vlist[i]->y + C*vlist[i]->z + D >= 0) { |
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| 239 | vlist[i]->index = vert_count; |
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| 240 | vert_count++; |
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| 241 | } else { |
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| 242 | vlist[i]->index = -1; |
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| 243 | } |
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| 244 | } |
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| 245 | |
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| 246 | // count the faces that are still valid |
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| 247 | face_count = 0; |
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| 248 | for (i = 0; i < nfaces; i++) { |
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| 249 | bool valid = (flist[i]->nverts > 0); |
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| 250 | for (j = 0; j < flist[i]->nverts; j++) { |
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| 251 | if (vlist[flist[i]->verts[j]]->index == -1) { |
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| 252 | valid = false; |
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| 253 | break; |
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| 254 | } |
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| 255 | } |
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| 256 | |
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| 257 | // If face not valid, set nverts to 0, so it won't |
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| 258 | // get written out later. |
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| 259 | if (valid) { |
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| 260 | face_count++; |
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| 261 | } else { |
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| 262 | flist[i]->nverts = 0; |
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| 263 | } |
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| 264 | } |
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| 265 | |
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| 266 | /* describe what properties go into the vertex and face elements */ |
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| 267 | |
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| 268 | ply_element_count (ply, "vertex", vert_count); |
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| 269 | ply_describe_property (ply, "vertex", &vert_props[0]); |
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| 270 | ply_describe_property (ply, "vertex", &vert_props[1]); |
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| 271 | ply_describe_property (ply, "vertex", &vert_props[2]); |
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| 272 | ply_describe_other_properties (ply, vert_other, offsetof(Vertex,other_props)); |
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| 273 | ply_element_count (ply, "face", face_count); |
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| 274 | ply_describe_property (ply, "face", &face_props[0]); |
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| 275 | ply_describe_other_properties (ply, face_other, offsetof(Face,other_props)); |
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| 276 | |
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| 277 | ply_describe_other_elements (ply, other_elements); |
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| 278 | |
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| 279 | for (i = 0; i < num_comments; i++) |
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| 280 | ply_put_comment (ply, comments[i]); |
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| 281 | |
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| 282 | for (i = 0; i < num_obj_info; i++) |
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| 283 | ply_put_obj_info (ply, obj_info[i]); |
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| 284 | |
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| 285 | ply_header_complete (ply); |
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| 286 | |
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| 287 | /* set up and write the vertex elements */ |
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| 288 | |
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| 289 | ply_put_element_setup (ply, "vertex"); |
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| 290 | |
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| 291 | for (i = 0; i < nverts; i++) |
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| 292 | if (vlist[i]->index > -1) |
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| 293 | ply_put_element (ply, (void *) vlist[i]); |
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| 294 | |
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| 295 | /* set up and write the face elements */ |
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| 296 | ply_put_element_setup (ply, "face"); |
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| 297 | |
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| 298 | for (i = 0; i < nfaces; i++) { |
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| 299 | if (flist[i]->nverts == 0) |
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| 300 | continue; |
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| 301 | for (j = 0; j < flist[i]->nverts; j++) |
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| 302 | flist[i]->verts[j] = (vlist[flist[i]->verts[j]])->index; |
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| 303 | ply_put_element (ply, (void *) flist[i]); |
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| 304 | } |
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| 305 | |
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| 306 | ply_put_other_elements (ply); |
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| 307 | |
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| 308 | /* close the PLY file */ |
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| 309 | ply_close (ply); |
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| 310 | } |
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