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-rw-r--r--progs/objviewer/glm.c1917
1 files changed, 1917 insertions, 0 deletions
diff --git a/progs/objviewer/glm.c b/progs/objviewer/glm.c
new file mode 100644
index 0000000000..7f36cdf28e
--- /dev/null
+++ b/progs/objviewer/glm.c
@@ -0,0 +1,1917 @@
+/*
+ * GLM library. Wavefront .obj file format reader/writer/manipulator.
+ *
+ * Written by Nate Robins, 1997.
+ * email: ndr@pobox.com
+ * www: http://www.pobox.com/~ndr
+ */
+
+/* includes */
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+#include "glm.h"
+#include "readtex.h"
+
+
+typedef unsigned char boolean;
+#define TRUE 1
+#define FALSE 0
+
+
+/* Some <math.h> files do not define M_PI... */
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+/* defines */
+#define T(x) model->triangles[(x)]
+
+
+/* enums */
+enum { X, Y, Z, W }; /* elements of a vertex */
+
+
+/* typedefs */
+
+/* _GLMnode: general purpose node
+ */
+typedef struct _GLMnode {
+ uint index;
+ boolean averaged;
+ struct _GLMnode* next;
+} GLMnode;
+
+/* strdup is actually not a standard ANSI C or POSIX routine
+ so implement a private one. OpenVMS does not have a strdup; Linux's
+ standard libc doesn't declare strdup by default (unless BSD or SVID
+ interfaces are requested). */
+static char *
+stralloc(const char *string)
+{
+ char *copy;
+
+ copy = malloc(strlen(string) + 1);
+ if (copy == NULL)
+ return NULL;
+ strcpy(copy, string);
+ return copy;
+}
+
+/* private functions */
+
+/* _glmMax: returns the maximum of two floats */
+static float
+_glmMax(float a, float b)
+{
+ if (a > b)
+ return a;
+ return b;
+}
+
+/* _glmAbs: returns the absolute value of a float */
+static float
+_glmAbs(float f)
+{
+ if (f < 0)
+ return -f;
+ return f;
+}
+
+/* _glmDot: compute the dot product of two vectors
+ *
+ * u - array of 3 floats (float u[3])
+ * v - array of 3 floats (float v[3])
+ */
+static float
+_glmDot(float* u, float* v)
+{
+ assert(u);
+ assert(v);
+
+ /* compute the dot product */
+ return u[X] * v[X] + u[Y] * v[Y] + u[Z] * v[Z];
+}
+
+/* _glmCross: compute the cross product of two vectors
+ *
+ * u - array of 3 floats (float u[3])
+ * v - array of 3 floats (float v[3])
+ * n - array of 3 floats (float n[3]) to return the cross product in
+ */
+static void
+_glmCross(float* u, float* v, float* n)
+{
+ assert(u);
+ assert(v);
+ assert(n);
+
+ /* compute the cross product (u x v for right-handed [ccw]) */
+ n[X] = u[Y] * v[Z] - u[Z] * v[Y];
+ n[Y] = u[Z] * v[X] - u[X] * v[Z];
+ n[Z] = u[X] * v[Y] - u[Y] * v[X];
+}
+
+/* _glmNormalize: normalize a vector
+ *
+ * n - array of 3 floats (float n[3]) to be normalized
+ */
+static void
+_glmNormalize(float* n)
+{
+ float l;
+
+ assert(n);
+
+ /* normalize */
+ l = (float)sqrt(n[X] * n[X] + n[Y] * n[Y] + n[Z] * n[Z]);
+ n[0] /= l;
+ n[1] /= l;
+ n[2] /= l;
+}
+
+/* _glmEqual: compares two vectors and returns TRUE if they are
+ * equal (within a certain threshold) or FALSE if not. An epsilon
+ * that works fairly well is 0.000001.
+ *
+ * u - array of 3 floats (float u[3])
+ * v - array of 3 floats (float v[3])
+ */
+static boolean
+_glmEqual(float* u, float* v, float epsilon)
+{
+ if (_glmAbs(u[0] - v[0]) < epsilon &&
+ _glmAbs(u[1] - v[1]) < epsilon &&
+ _glmAbs(u[2] - v[2]) < epsilon)
+ {
+ return TRUE;
+ }
+ return FALSE;
+}
+
+/* _glmWeldVectors: eliminate (weld) vectors that are within an
+ * epsilon of each other.
+ *
+ * vectors - array of float[3]'s to be welded
+ * numvectors - number of float[3]'s in vectors
+ * epsilon - maximum difference between vectors
+ *
+ */
+static float*
+_glmWeldVectors(float* vectors, uint* numvectors, float epsilon)
+{
+ float* copies;
+ uint copied;
+ uint i, j;
+
+ copies = (float*)malloc(sizeof(float) * 3 * (*numvectors + 1));
+ memcpy(copies, vectors, (sizeof(float) * 3 * (*numvectors + 1)));
+
+ copied = 1;
+ for (i = 1; i <= *numvectors; i++) {
+ for (j = 1; j <= copied; j++) {
+ if (_glmEqual(&vectors[3 * i], &copies[3 * j], epsilon)) {
+ goto duplicate;
+ }
+ }
+
+ /* must not be any duplicates -- add to the copies array */
+ copies[3 * copied + 0] = vectors[3 * i + 0];
+ copies[3 * copied + 1] = vectors[3 * i + 1];
+ copies[3 * copied + 2] = vectors[3 * i + 2];
+ j = copied; /* pass this along for below */
+ copied++;
+
+ duplicate:
+ /* set the first component of this vector to point at the correct
+ index into the new copies array */
+ vectors[3 * i + 0] = (float)j;
+ }
+
+ *numvectors = copied-1;
+ return copies;
+}
+
+/* _glmFindGroup: Find a group in the model
+ */
+static GLMgroup*
+_glmFindGroup(GLMmodel* model, char* name)
+{
+ GLMgroup* group;
+
+ assert(model);
+
+ group = model->groups;
+ while(group) {
+ if (!strcmp(name, group->name))
+ break;
+ group = group->next;
+ }
+
+ return group;
+}
+
+/* _glmAddGroup: Add a group to the model
+ */
+static GLMgroup*
+_glmAddGroup(GLMmodel* model, char* name)
+{
+ GLMgroup* group;
+
+ group = _glmFindGroup(model, name);
+ if (!group) {
+ group = (GLMgroup*)malloc(sizeof(GLMgroup));
+ group->name = stralloc(name);
+ group->material = 0;
+ group->numtriangles = 0;
+ group->triangles = NULL;
+ group->next = model->groups;
+ model->groups = group;
+ model->numgroups++;
+ }
+
+ return group;
+}
+
+/* _glmFindGroup: Find a material in the model
+ */
+static uint
+_glmFindMaterial(GLMmodel* model, char* name)
+{
+ uint i;
+
+ for (i = 0; i < model->nummaterials; i++) {
+ if (!strcmp(model->materials[i].name, name))
+ goto found;
+ }
+
+ /* didn't find the name, so set it as the default material */
+ printf("_glmFindMaterial(): can't find material \"%s\".\n", name);
+ i = 0;
+
+found:
+ return i;
+}
+
+
+/* _glmDirName: return the directory given a path
+ *
+ * path - filesystem path
+ *
+ * The return value should be free'd.
+ */
+static char*
+_glmDirName(char* path)
+{
+ char* dir;
+ char* s;
+
+ dir = stralloc(path);
+
+ s = strrchr(dir, '/');
+ if (s)
+ s[1] = '\0';
+ else
+ dir[0] = '\0';
+
+ return dir;
+}
+
+
+/* _glmReadMTL: read a wavefront material library file
+ *
+ * model - properly initialized GLMmodel structure
+ * name - name of the material library
+ */
+static void
+_glmReadMTL(GLMmodel* model, char* name)
+{
+ FILE* file;
+ char* dir;
+ char* filename;
+ char buf[128], buf2[128];
+ uint nummaterials, i;
+ GLMmaterial *mat;
+
+ dir = _glmDirName(model->pathname);
+ filename = (char*)malloc(sizeof(char) * (strlen(dir) + strlen(name) + 1));
+ strcpy(filename, dir);
+ strcat(filename, name);
+ free(dir);
+
+ /* open the file */
+ file = fopen(filename, "r");
+ if (!file) {
+ fprintf(stderr, "_glmReadMTL() failed: can't open material file \"%s\".\n",
+ filename);
+ exit(1);
+ }
+ free(filename);
+
+ /* count the number of materials in the file */
+ nummaterials = 1;
+ while(fscanf(file, "%s", buf) != EOF) {
+ switch(buf[0]) {
+ case '#': /* comment */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ case 'n': /* newmtl */
+ fgets(buf, sizeof(buf), file);
+ nummaterials++;
+ sscanf(buf, "%s %s", buf, buf);
+ break;
+ default:
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ }
+ }
+
+ rewind(file);
+
+ /* allocate memory for the materials */
+ model->materials = (GLMmaterial*)calloc(nummaterials, sizeof(GLMmaterial));
+ model->nummaterials = nummaterials;
+
+ /* set the default material */
+ for (i = 0; i < nummaterials; i++) {
+ model->materials[i].name = NULL;
+ model->materials[i].shininess = 0;
+ model->materials[i].diffuse[0] = 0.8;
+ model->materials[i].diffuse[1] = 0.8;
+ model->materials[i].diffuse[2] = 0.8;
+ model->materials[i].diffuse[3] = 1.0;
+ model->materials[i].ambient[0] = 0.2;
+ model->materials[i].ambient[1] = 0.2;
+ model->materials[i].ambient[2] = 0.2;
+ model->materials[i].ambient[3] = 0.0;
+ model->materials[i].specular[0] = 0.0;
+ model->materials[i].specular[1] = 0.0;
+ model->materials[i].specular[2] = 0.0;
+ model->materials[i].specular[3] = 0.0;
+ }
+ model->materials[0].name = stralloc("default");
+
+ /* now, read in the data */
+ nummaterials = 0;
+
+ mat = &model->materials[nummaterials];
+
+ while(fscanf(file, "%s", buf) != EOF) {
+ switch(buf[0]) {
+ case '#': /* comment */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ case 'n': /* newmtl */
+ fgets(buf, sizeof(buf), file);
+ sscanf(buf, "%s %s", buf, buf);
+ nummaterials++;
+ model->materials[nummaterials].name = stralloc(buf);
+ break;
+ case 'N':
+ fscanf(file, "%f", &model->materials[nummaterials].shininess);
+ /* wavefront shininess is from [0, 1000], so scale for OpenGL */
+ model->materials[nummaterials].shininess /= 1000.0;
+ model->materials[nummaterials].shininess *= 128.0;
+ mat = &model->materials[nummaterials];
+ break;
+ case 'K':
+ switch(buf[1]) {
+ case 'd':
+ fscanf(file, "%f %f %f",
+ &model->materials[nummaterials].diffuse[0],
+ &model->materials[nummaterials].diffuse[1],
+ &model->materials[nummaterials].diffuse[2]);
+ break;
+ case 's':
+ fscanf(file, "%f %f %f",
+ &model->materials[nummaterials].specular[0],
+ &model->materials[nummaterials].specular[1],
+ &model->materials[nummaterials].specular[2]);
+ break;
+ case 'a':
+ fscanf(file, "%f %f %f",
+ &model->materials[nummaterials].ambient[0],
+ &model->materials[nummaterials].ambient[1],
+ &model->materials[nummaterials].ambient[2]);
+ break;
+ default:
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ }
+ break;
+ case 'd': /* alpha? */
+ fscanf(file, "%f",
+ &model->materials[nummaterials].diffuse[3]);
+ break;
+ case 'm': /* texture map */
+ fscanf(file, "%s", buf2);
+ /*printf("map %s\n", buf2);*/
+ mat->map_kd = strdup(buf2);
+ break;
+
+ default:
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ }
+ }
+}
+
+
+/* _glmWriteMTL: write a wavefront material library file
+ *
+ * model - properly initialized GLMmodel structure
+ * modelpath - pathname of the model being written
+ * mtllibname - name of the material library to be written
+ */
+static void
+_glmWriteMTL(GLMmodel* model, char* modelpath, char* mtllibname)
+{
+ FILE* file;
+ char* dir;
+ char* filename;
+ GLMmaterial* material;
+ uint i;
+
+ dir = _glmDirName(modelpath);
+ filename = (char*)malloc(sizeof(char) * (strlen(dir) + strlen(mtllibname)));
+ strcpy(filename, dir);
+ strcat(filename, mtllibname);
+ free(dir);
+
+ /* open the file */
+ file = fopen(filename, "w");
+ if (!file) {
+ fprintf(stderr, "_glmWriteMTL() failed: can't open file \"%s\".\n",
+ filename);
+ exit(1);
+ }
+ free(filename);
+
+ /* spit out a header */
+ fprintf(file, "# \n");
+ fprintf(file, "# Wavefront MTL generated by GLM library\n");
+ fprintf(file, "# \n");
+ fprintf(file, "# GLM library copyright (C) 1997 by Nate Robins\n");
+ fprintf(file, "# email: ndr@pobox.com\n");
+ fprintf(file, "# www: http://www.pobox.com/~ndr\n");
+ fprintf(file, "# \n\n");
+
+ for (i = 0; i < model->nummaterials; i++) {
+ material = &model->materials[i];
+ fprintf(file, "newmtl %s\n", material->name);
+ fprintf(file, "Ka %f %f %f\n",
+ material->ambient[0], material->ambient[1], material->ambient[2]);
+ fprintf(file, "Kd %f %f %f\n",
+ material->diffuse[0], material->diffuse[1], material->diffuse[2]);
+ fprintf(file, "Ks %f %f %f\n",
+ material->specular[0],material->specular[1],material->specular[2]);
+ fprintf(file, "Ns %f\n", material->shininess);
+ fprintf(file, "\n");
+ }
+}
+
+
+/* _glmFirstPass: first pass at a Wavefront OBJ file that gets all the
+ * statistics of the model (such as #vertices, #normals, etc)
+ *
+ * model - properly initialized GLMmodel structure
+ * file - (fopen'd) file descriptor
+ */
+static void
+_glmFirstPass(GLMmodel* model, FILE* file)
+{
+ uint numvertices; /* number of vertices in model */
+ uint numnormals; /* number of normals in model */
+ uint numtexcoords; /* number of texcoords in model */
+ uint numtriangles; /* number of triangles in model */
+ GLMgroup* group; /* current group */
+ unsigned v, n, t;
+ char buf[128];
+
+ /* make a default group */
+ group = _glmAddGroup(model, "default");
+
+ numvertices = numnormals = numtexcoords = numtriangles = 0;
+ while(fscanf(file, "%s", buf) != EOF) {
+ switch(buf[0]) {
+ case '#': /* comment */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ case 'v': /* v, vn, vt */
+ switch(buf[1]) {
+ case '\0': /* vertex */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ numvertices++;
+ break;
+ case 'n': /* normal */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ numnormals++;
+ break;
+ case 't': /* texcoord */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ numtexcoords++;
+ break;
+ default:
+ printf("_glmFirstPass(): Unknown token \"%s\".\n", buf);
+ exit(1);
+ break;
+ }
+ break;
+ case 'm':
+ fgets(buf, sizeof(buf), file);
+ sscanf(buf, "%s %s", buf, buf);
+ model->mtllibname = stralloc(buf);
+ _glmReadMTL(model, buf);
+ break;
+ case 'u':
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ case 'g': /* group */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ sscanf(buf, "%s", buf);
+ group = _glmAddGroup(model, buf);
+ break;
+ case 'f': /* face */
+ v = n = t = 0;
+ fscanf(file, "%s", buf);
+ /* can be one of %d, %d//%d, %d/%d, %d/%d/%d %d//%d */
+ if (strstr(buf, "//")) {
+ /* v//n */
+ sscanf(buf, "%u//%u", &v, &n);
+ fscanf(file, "%u//%u", &v, &n);
+ fscanf(file, "%u//%u", &v, &n);
+ numtriangles++;
+ group->numtriangles++;
+ while(fscanf(file, "%u//%u", &v, &n) > 0) {
+ numtriangles++;
+ group->numtriangles++;
+ }
+ } else if (sscanf(buf, "%u/%u/%u", &v, &t, &n) == 3) {
+ /* v/t/n */
+ fscanf(file, "%u/%u/%u", &v, &t, &n);
+ fscanf(file, "%u/%u/%u", &v, &t, &n);
+ numtriangles++;
+ group->numtriangles++;
+ while(fscanf(file, "%u/%u/%u", &v, &t, &n) > 0) {
+ numtriangles++;
+ group->numtriangles++;
+ }
+ } else if (sscanf(buf, "%u/%u", &v, &t) == 2) {
+ /* v/t */
+ fscanf(file, "%u/%u", &v, &t);
+ fscanf(file, "%u/%u", &v, &t);
+ numtriangles++;
+ group->numtriangles++;
+ while(fscanf(file, "%u/%u", &v, &t) > 0) {
+ numtriangles++;
+ group->numtriangles++;
+ }
+ } else {
+ /* v */
+ fscanf(file, "%u", &v);
+ fscanf(file, "%u", &v);
+ numtriangles++;
+ group->numtriangles++;
+ while(fscanf(file, "%u", &v) > 0) {
+ numtriangles++;
+ group->numtriangles++;
+ }
+ }
+ break;
+
+ default:
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ }
+ }
+
+#if 0
+ /* announce the model statistics */
+ printf(" Vertices: %d\n", numvertices);
+ printf(" Normals: %d\n", numnormals);
+ printf(" Texcoords: %d\n", numtexcoords);
+ printf(" Triangles: %d\n", numtriangles);
+ printf(" Groups: %d\n", model->numgroups);
+#endif
+
+ /* set the stats in the model structure */
+ model->numvertices = numvertices;
+ model->numnormals = numnormals;
+ model->numtexcoords = numtexcoords;
+ model->numtriangles = numtriangles;
+
+ /* allocate memory for the triangles in each group */
+ group = model->groups;
+ while(group) {
+ group->triangles = (uint*)malloc(sizeof(uint) * group->numtriangles);
+ group->numtriangles = 0;
+ group = group->next;
+ }
+}
+
+/* _glmSecondPass: second pass at a Wavefront OBJ file that gets all
+ * the data.
+ *
+ * model - properly initialized GLMmodel structure
+ * file - (fopen'd) file descriptor
+ */
+static void
+_glmSecondPass(GLMmodel* model, FILE* file)
+{
+ uint numvertices; /* number of vertices in model */
+ uint numnormals; /* number of normals in model */
+ uint numtexcoords; /* number of texcoords in model */
+ uint numtriangles; /* number of triangles in model */
+ float* vertices; /* array of vertices */
+ float* normals; /* array of normals */
+ float* texcoords; /* array of texture coordinates */
+ GLMgroup* group; /* current group pointer */
+ uint material; /* current material */
+ uint v, n, t;
+ char buf[128];
+
+ /* set the pointer shortcuts */
+ vertices = model->vertices;
+ normals = model->normals;
+ texcoords = model->texcoords;
+ group = model->groups;
+
+ /* on the second pass through the file, read all the data into the
+ allocated arrays */
+ numvertices = numnormals = numtexcoords = 1;
+ numtriangles = 0;
+ material = 0;
+ while(fscanf(file, "%s", buf) != EOF) {
+ switch(buf[0]) {
+ case '#': /* comment */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ case 'v': /* v, vn, vt */
+ switch(buf[1]) {
+ case '\0': /* vertex */
+ fscanf(file, "%f %f %f",
+ &vertices[3 * numvertices + X],
+ &vertices[3 * numvertices + Y],
+ &vertices[3 * numvertices + Z]);
+ numvertices++;
+ break;
+ case 'n': /* normal */
+ fscanf(file, "%f %f %f",
+ &normals[3 * numnormals + X],
+ &normals[3 * numnormals + Y],
+ &normals[3 * numnormals + Z]);
+ numnormals++;
+ break;
+ case 't': /* texcoord */
+ fscanf(file, "%f %f",
+ &texcoords[2 * numtexcoords + X],
+ &texcoords[2 * numtexcoords + Y]);
+ numtexcoords++;
+ break;
+ }
+ break;
+ case 'u':
+ fgets(buf, sizeof(buf), file);
+ sscanf(buf, "%s %s", buf, buf);
+ material = _glmFindMaterial(model, buf);
+ if (!group->material)
+ group->material = material;
+ /*printf("material %s = %u\n", buf, material);*/
+ break;
+ case 'g': /* group */
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ sscanf(buf, "%s", buf);
+ group = _glmFindGroup(model, buf);
+ group->material = material;
+ /*printf("GROUP %s material %u\n", buf, material);*/
+ break;
+ case 'f': /* face */
+ v = n = t = 0;
+ fscanf(file, "%s", buf);
+ /* can be one of %d, %d//%d, %d/%d, %d/%d/%d %d//%d */
+ if (strstr(buf, "//")) {
+ /* v//n */
+ sscanf(buf, "%u//%u", &v, &n);
+ T(numtriangles).vindices[0] = v;
+ T(numtriangles).nindices[0] = n;
+ fscanf(file, "%u//%u", &v, &n);
+ T(numtriangles).vindices[1] = v;
+ T(numtriangles).nindices[1] = n;
+ fscanf(file, "%u//%u", &v, &n);
+ T(numtriangles).vindices[2] = v;
+ T(numtriangles).nindices[2] = n;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ while(fscanf(file, "%u//%u", &v, &n) > 0) {
+ T(numtriangles).vindices[0] = T(numtriangles-1).vindices[0];
+ T(numtriangles).nindices[0] = T(numtriangles-1).nindices[0];
+ T(numtriangles).vindices[1] = T(numtriangles-1).vindices[2];
+ T(numtriangles).nindices[1] = T(numtriangles-1).nindices[2];
+ T(numtriangles).vindices[2] = v;
+ T(numtriangles).nindices[2] = n;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ }
+ } else if (sscanf(buf, "%u/%u/%u", &v, &t, &n) == 3) {
+ /* v/t/n */
+ T(numtriangles).vindices[0] = v;
+ T(numtriangles).tindices[0] = t;
+ T(numtriangles).nindices[0] = n;
+ fscanf(file, "%u/%u/%u", &v, &t, &n);
+ T(numtriangles).vindices[1] = v;
+ T(numtriangles).tindices[1] = t;
+ T(numtriangles).nindices[1] = n;
+ fscanf(file, "%u/%u/%u", &v, &t, &n);
+ T(numtriangles).vindices[2] = v;
+ T(numtriangles).tindices[2] = t;
+ T(numtriangles).nindices[2] = n;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ while(fscanf(file, "%u/%u/%u", &v, &t, &n) > 0) {
+ T(numtriangles).vindices[0] = T(numtriangles-1).vindices[0];
+ T(numtriangles).tindices[0] = T(numtriangles-1).tindices[0];
+ T(numtriangles).nindices[0] = T(numtriangles-1).nindices[0];
+ T(numtriangles).vindices[1] = T(numtriangles-1).vindices[2];
+ T(numtriangles).tindices[1] = T(numtriangles-1).tindices[2];
+ T(numtriangles).nindices[1] = T(numtriangles-1).nindices[2];
+ T(numtriangles).vindices[2] = v;
+ T(numtriangles).tindices[2] = t;
+ T(numtriangles).nindices[2] = n;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ }
+ } else if (sscanf(buf, "%u/%u", &v, &t) == 2) {
+ /* v/t */
+ T(numtriangles).vindices[0] = v;
+ T(numtriangles).tindices[0] = t;
+ fscanf(file, "%u/%u", &v, &t);
+ T(numtriangles).vindices[1] = v;
+ T(numtriangles).tindices[1] = t;
+ fscanf(file, "%u/%u", &v, &t);
+ T(numtriangles).vindices[2] = v;
+ T(numtriangles).tindices[2] = t;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ while(fscanf(file, "%u/%u", &v, &t) > 0) {
+ T(numtriangles).vindices[0] = T(numtriangles-1).vindices[0];
+ T(numtriangles).tindices[0] = T(numtriangles-1).tindices[0];
+ T(numtriangles).vindices[1] = T(numtriangles-1).vindices[2];
+ T(numtriangles).tindices[1] = T(numtriangles-1).tindices[2];
+ T(numtriangles).vindices[2] = v;
+ T(numtriangles).tindices[2] = t;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ }
+ } else {
+ /* v */
+ sscanf(buf, "%u", &v);
+ T(numtriangles).vindices[0] = v;
+ fscanf(file, "%u", &v);
+ T(numtriangles).vindices[1] = v;
+ fscanf(file, "%u", &v);
+ T(numtriangles).vindices[2] = v;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ while(fscanf(file, "%u", &v) > 0) {
+ T(numtriangles).vindices[0] = T(numtriangles-1).vindices[0];
+ T(numtriangles).vindices[1] = T(numtriangles-1).vindices[2];
+ T(numtriangles).vindices[2] = v;
+ group->triangles[group->numtriangles++] = numtriangles;
+ numtriangles++;
+ }
+ }
+ break;
+
+ default:
+ /* eat up rest of line */
+ fgets(buf, sizeof(buf), file);
+ break;
+ }
+ }
+
+#if 0
+ /* announce the memory requirements */
+ printf(" Memory: %d bytes\n",
+ numvertices * 3*sizeof(float) +
+ numnormals * 3*sizeof(float) * (numnormals ? 1 : 0) +
+ numtexcoords * 3*sizeof(float) * (numtexcoords ? 1 : 0) +
+ numtriangles * sizeof(GLMtriangle));
+#endif
+}
+
+
+
+
+/* public functions */
+
+/* glmUnitize: "unitize" a model by translating it to the origin and
+ * scaling it to fit in a unit cube around the origin. Returns the
+ * scalefactor used.
+ *
+ * model - properly initialized GLMmodel structure
+ */
+float
+glmUnitize(GLMmodel* model)
+{
+ uint i;
+ float maxx, minx, maxy, miny, maxz, minz;
+ float cx, cy, cz, w, h, d;
+ float scale;
+
+ assert(model);
+ assert(model->vertices);
+
+ /* get the max/mins */
+ maxx = minx = model->vertices[3 + X];
+ maxy = miny = model->vertices[3 + Y];
+ maxz = minz = model->vertices[3 + Z];
+ for (i = 1; i <= model->numvertices; i++) {
+ if (maxx < model->vertices[3 * i + X])
+ maxx = model->vertices[3 * i + X];
+ if (minx > model->vertices[3 * i + X])
+ minx = model->vertices[3 * i + X];
+
+ if (maxy < model->vertices[3 * i + Y])
+ maxy = model->vertices[3 * i + Y];
+ if (miny > model->vertices[3 * i + Y])
+ miny = model->vertices[3 * i + Y];
+
+ if (maxz < model->vertices[3 * i + Z])
+ maxz = model->vertices[3 * i + Z];
+ if (minz > model->vertices[3 * i + Z])
+ minz = model->vertices[3 * i + Z];
+ }
+
+ /* calculate model width, height, and depth */
+ w = _glmAbs(maxx) + _glmAbs(minx);
+ h = _glmAbs(maxy) + _glmAbs(miny);
+ d = _glmAbs(maxz) + _glmAbs(minz);
+
+ /* calculate center of the model */
+ cx = (maxx + minx) / 2.0;
+ cy = (maxy + miny) / 2.0;
+ cz = (maxz + minz) / 2.0;
+
+ /* calculate unitizing scale factor */
+ scale = 2.0 / _glmMax(_glmMax(w, h), d);
+
+ /* translate around center then scale */
+ for (i = 1; i <= model->numvertices; i++) {
+ model->vertices[3 * i + X] -= cx;
+ model->vertices[3 * i + Y] -= cy;
+ model->vertices[3 * i + Z] -= cz;
+ model->vertices[3 * i + X] *= scale;
+ model->vertices[3 * i + Y] *= scale;
+ model->vertices[3 * i + Z] *= scale;
+ }
+
+ return scale;
+}
+
+/* glmDimensions: Calculates the dimensions (width, height, depth) of
+ * a model.
+ *
+ * model - initialized GLMmodel structure
+ * dimensions - array of 3 floats (float dimensions[3])
+ */
+void
+glmDimensions(GLMmodel* model, float* dimensions)
+{
+ uint i;
+ float maxx, minx, maxy, miny, maxz, minz;
+
+ assert(model);
+ assert(model->vertices);
+ assert(dimensions);
+
+ /* get the max/mins */
+ maxx = minx = model->vertices[3 + X];
+ maxy = miny = model->vertices[3 + Y];
+ maxz = minz = model->vertices[3 + Z];
+ for (i = 1; i <= model->numvertices; i++) {
+ if (maxx < model->vertices[3 * i + X])
+ maxx = model->vertices[3 * i + X];
+ if (minx > model->vertices[3 * i + X])
+ minx = model->vertices[3 * i + X];
+
+ if (maxy < model->vertices[3 * i + Y])
+ maxy = model->vertices[3 * i + Y];
+ if (miny > model->vertices[3 * i + Y])
+ miny = model->vertices[3 * i + Y];
+
+ if (maxz < model->vertices[3 * i + Z])
+ maxz = model->vertices[3 * i + Z];
+ if (minz > model->vertices[3 * i + Z])
+ minz = model->vertices[3 * i + Z];
+ }
+
+ /* calculate model width, height, and depth */
+ dimensions[X] = _glmAbs(maxx) + _glmAbs(minx);
+ dimensions[Y] = _glmAbs(maxy) + _glmAbs(miny);
+ dimensions[Z] = _glmAbs(maxz) + _glmAbs(minz);
+}
+
+/* glmScale: Scales a model by a given amount.
+ *
+ * model - properly initialized GLMmodel structure
+ * scale - scalefactor (0.5 = half as large, 2.0 = twice as large)
+ */
+void
+glmScale(GLMmodel* model, float scale)
+{
+ uint i;
+
+ for (i = 1; i <= model->numvertices; i++) {
+ model->vertices[3 * i + X] *= scale;
+ model->vertices[3 * i + Y] *= scale;
+ model->vertices[3 * i + Z] *= scale;
+ }
+}
+
+/* glmReverseWinding: Reverse the polygon winding for all polygons in
+ * this model. Default winding is counter-clockwise. Also changes
+ * the direction of the normals.
+ *
+ * model - properly initialized GLMmodel structure
+ */
+void
+glmReverseWinding(GLMmodel* model)
+{
+ uint i, swap;
+
+ assert(model);
+
+ for (i = 0; i < model->numtriangles; i++) {
+ swap = T(i).vindices[0];
+ T(i).vindices[0] = T(i).vindices[2];
+ T(i).vindices[2] = swap;
+
+ if (model->numnormals) {
+ swap = T(i).nindices[0];
+ T(i).nindices[0] = T(i).nindices[2];
+ T(i).nindices[2] = swap;
+ }
+
+ if (model->numtexcoords) {
+ swap = T(i).tindices[0];
+ T(i).tindices[0] = T(i).tindices[2];
+ T(i).tindices[2] = swap;
+ }
+ }
+
+ /* reverse facet normals */
+ for (i = 1; i <= model->numfacetnorms; i++) {
+ model->facetnorms[3 * i + X] = -model->facetnorms[3 * i + X];
+ model->facetnorms[3 * i + Y] = -model->facetnorms[3 * i + Y];
+ model->facetnorms[3 * i + Z] = -model->facetnorms[3 * i + Z];
+ }
+
+ /* reverse vertex normals */
+ for (i = 1; i <= model->numnormals; i++) {
+ model->normals[3 * i + X] = -model->normals[3 * i + X];
+ model->normals[3 * i + Y] = -model->normals[3 * i + Y];
+ model->normals[3 * i + Z] = -model->normals[3 * i + Z];
+ }
+}
+
+/* glmFacetNormals: Generates facet normals for a model (by taking the
+ * cross product of the two vectors derived from the sides of each
+ * triangle). Assumes a counter-clockwise winding.
+ *
+ * model - initialized GLMmodel structure
+ */
+void
+glmFacetNormals(GLMmodel* model)
+{
+ uint i;
+ float u[3];
+ float v[3];
+
+ assert(model);
+ assert(model->vertices);
+
+ /* clobber any old facetnormals */
+ if (model->facetnorms)
+ free(model->facetnorms);
+
+ /* allocate memory for the new facet normals */
+ model->numfacetnorms = model->numtriangles;
+ model->facetnorms = (float*)malloc(sizeof(float) *
+ 3 * (model->numfacetnorms + 1));
+
+ for (i = 0; i < model->numtriangles; i++) {
+ model->triangles[i].findex = i+1;
+
+ u[X] = model->vertices[3 * T(i).vindices[1] + X] -
+ model->vertices[3 * T(i).vindices[0] + X];
+ u[Y] = model->vertices[3 * T(i).vindices[1] + Y] -
+ model->vertices[3 * T(i).vindices[0] + Y];
+ u[Z] = model->vertices[3 * T(i).vindices[1] + Z] -
+ model->vertices[3 * T(i).vindices[0] + Z];
+
+ v[X] = model->vertices[3 * T(i).vindices[2] + X] -
+ model->vertices[3 * T(i).vindices[0] + X];
+ v[Y] = model->vertices[3 * T(i).vindices[2] + Y] -
+ model->vertices[3 * T(i).vindices[0] + Y];
+ v[Z] = model->vertices[3 * T(i).vindices[2] + Z] -
+ model->vertices[3 * T(i).vindices[0] + Z];
+
+ _glmCross(u, v, &model->facetnorms[3 * (i+1)]);
+ _glmNormalize(&model->facetnorms[3 * (i+1)]);
+ }
+}
+
+/* glmVertexNormals: Generates smooth vertex normals for a model.
+ * First builds a list of all the triangles each vertex is in. Then
+ * loops through each vertex in the the list averaging all the facet
+ * normals of the triangles each vertex is in. Finally, sets the
+ * normal index in the triangle for the vertex to the generated smooth
+ * normal. If the dot product of a facet normal and the facet normal
+ * associated with the first triangle in the list of triangles the
+ * current vertex is in is greater than the cosine of the angle
+ * parameter to the function, that facet normal is not added into the
+ * average normal calculation and the corresponding vertex is given
+ * the facet normal. This tends to preserve hard edges. The angle to
+ * use depends on the model, but 90 degrees is usually a good start.
+ *
+ * model - initialized GLMmodel structure
+ * angle - maximum angle (in degrees) to smooth across
+ */
+void
+glmVertexNormals(GLMmodel* model, float angle)
+{
+ GLMnode* node;
+ GLMnode* tail;
+ GLMnode** members;
+ float* normals;
+ uint numnormals;
+ float average[3];
+ float dot, cos_angle;
+ uint i, avg;
+
+ assert(model);
+ assert(model->facetnorms);
+
+ /* calculate the cosine of the angle (in degrees) */
+ cos_angle = cos(angle * M_PI / 180.0);
+
+ /* nuke any previous normals */
+ if (model->normals)
+ free(model->normals);
+
+ /* allocate space for new normals */
+ model->numnormals = model->numtriangles * 3; /* 3 normals per triangle */
+ model->normals = (float*)malloc(sizeof(float)* 3* (model->numnormals+1));
+
+ /* allocate a structure that will hold a linked list of triangle
+ indices for each vertex */
+ members = (GLMnode**)malloc(sizeof(GLMnode*) * (model->numvertices + 1));
+ for (i = 1; i <= model->numvertices; i++)
+ members[i] = NULL;
+
+ /* for every triangle, create a node for each vertex in it */
+ for (i = 0; i < model->numtriangles; i++) {
+ node = (GLMnode*)malloc(sizeof(GLMnode));
+ node->index = i;
+ node->next = members[T(i).vindices[0]];
+ members[T(i).vindices[0]] = node;
+
+ node = (GLMnode*)malloc(sizeof(GLMnode));
+ node->index = i;
+ node->next = members[T(i).vindices[1]];
+ members[T(i).vindices[1]] = node;
+
+ node = (GLMnode*)malloc(sizeof(GLMnode));
+ node->index = i;
+ node->next = members[T(i).vindices[2]];
+ members[T(i).vindices[2]] = node;
+ }
+
+ /* calculate the average normal for each vertex */
+ numnormals = 1;
+ for (i = 1; i <= model->numvertices; i++) {
+ /* calculate an average normal for this vertex by averaging the
+ facet normal of every triangle this vertex is in */
+ node = members[i];
+ if (!node)
+ fprintf(stderr, "glmVertexNormals(): vertex w/o a triangle\n");
+ average[0] = 0.0; average[1] = 0.0; average[2] = 0.0;
+ avg = 0;
+ while (node) {
+ /* only average if the dot product of the angle between the two
+ facet normals is greater than the cosine of the threshold
+ angle -- or, said another way, the angle between the two
+ facet normals is less than (or equal to) the threshold angle */
+ dot = _glmDot(&model->facetnorms[3 * T(node->index).findex],
+ &model->facetnorms[3 * T(members[i]->index).findex]);
+ if (dot > cos_angle) {
+ node->averaged = TRUE;
+ average[0] += model->facetnorms[3 * T(node->index).findex + 0];
+ average[1] += model->facetnorms[3 * T(node->index).findex + 1];
+ average[2] += model->facetnorms[3 * T(node->index).findex + 2];
+ avg = 1; /* we averaged at least one normal! */
+ } else {
+ node->averaged = FALSE;
+ }
+ node = node->next;
+ }
+
+ if (avg) {
+ /* normalize the averaged normal */
+ _glmNormalize(average);
+
+ /* add the normal to the vertex normals list */
+ model->normals[3 * numnormals + 0] = average[0];
+ model->normals[3 * numnormals + 1] = average[1];
+ model->normals[3 * numnormals + 2] = average[2];
+ avg = numnormals;
+ numnormals++;
+ }
+
+ /* set the normal of this vertex in each triangle it is in */
+ node = members[i];
+ while (node) {
+ if (node->averaged) {
+ /* if this node was averaged, use the average normal */
+ if (T(node->index).vindices[0] == i)
+ T(node->index).nindices[0] = avg;
+ else if (T(node->index).vindices[1] == i)
+ T(node->index).nindices[1] = avg;
+ else if (T(node->index).vindices[2] == i)
+ T(node->index).nindices[2] = avg;
+ } else {
+ /* if this node wasn't averaged, use the facet normal */
+ model->normals[3 * numnormals + 0] =
+ model->facetnorms[3 * T(node->index).findex + 0];
+ model->normals[3 * numnormals + 1] =
+ model->facetnorms[3 * T(node->index).findex + 1];
+ model->normals[3 * numnormals + 2] =
+ model->facetnorms[3 * T(node->index).findex + 2];
+ if (T(node->index).vindices[0] == i)
+ T(node->index).nindices[0] = numnormals;
+ else if (T(node->index).vindices[1] == i)
+ T(node->index).nindices[1] = numnormals;
+ else if (T(node->index).vindices[2] == i)
+ T(node->index).nindices[2] = numnormals;
+ numnormals++;
+ }
+ node = node->next;
+ }
+ }
+
+ model->numnormals = numnormals - 1;
+
+ /* free the member information */
+ for (i = 1; i <= model->numvertices; i++) {
+ node = members[i];
+ while (node) {
+ tail = node;
+ node = node->next;
+ free(tail);
+ }
+ }
+ free(members);
+
+ /* pack the normals array (we previously allocated the maximum
+ number of normals that could possibly be created (numtriangles *
+ 3), so get rid of some of them (usually alot unless none of the
+ facet normals were averaged)) */
+ normals = model->normals;
+ model->normals = (float*)malloc(sizeof(float)* 3* (model->numnormals+1));
+ for (i = 1; i <= model->numnormals; i++) {
+ model->normals[3 * i + 0] = normals[3 * i + 0];
+ model->normals[3 * i + 1] = normals[3 * i + 1];
+ model->normals[3 * i + 2] = normals[3 * i + 2];
+ }
+ free(normals);
+
+ printf("glmVertexNormals(): %d normals generated\n", model->numnormals);
+}
+
+
+/* glmLinearTexture: Generates texture coordinates according to a
+ * linear projection of the texture map. It generates these by
+ * linearly mapping the vertices onto a square.
+ *
+ * model - pointer to initialized GLMmodel structure
+ */
+void
+glmLinearTexture(GLMmodel* model)
+{
+ GLMgroup *group;
+ float dimensions[3];
+ float x, y, scalefactor;
+ uint i;
+
+ assert(model);
+
+ if (model->texcoords)
+ free(model->texcoords);
+ model->numtexcoords = model->numvertices;
+ model->texcoords=(float*)malloc(sizeof(float)*2*(model->numtexcoords+1));
+
+ glmDimensions(model, dimensions);
+ scalefactor = 2.0 /
+ _glmAbs(_glmMax(_glmMax(dimensions[0], dimensions[1]), dimensions[2]));
+
+ /* do the calculations */
+ for(i = 1; i <= model->numvertices; i++) {
+ x = model->vertices[3 * i + 0] * scalefactor;
+ y = model->vertices[3 * i + 2] * scalefactor;
+ model->texcoords[2 * i + 0] = (x + 1.0) / 2.0;
+ model->texcoords[2 * i + 1] = (y + 1.0) / 2.0;
+ }
+
+ /* go through and put texture coordinate indices in all the triangles */
+ group = model->groups;
+ while(group) {
+ for(i = 0; i < group->numtriangles; i++) {
+ T(group->triangles[i]).tindices[0] = T(group->triangles[i]).vindices[0];
+ T(group->triangles[i]).tindices[1] = T(group->triangles[i]).vindices[1];
+ T(group->triangles[i]).tindices[2] = T(group->triangles[i]).vindices[2];
+ }
+ group = group->next;
+ }
+
+#if 0
+ printf("glmLinearTexture(): generated %d linear texture coordinates\n",
+ model->numtexcoords);
+#endif
+}
+
+/* glmSpheremapTexture: Generates texture coordinates according to a
+ * spherical projection of the texture map. Sometimes referred to as
+ * spheremap, or reflection map texture coordinates. It generates
+ * these by using the normal to calculate where that vertex would map
+ * onto a sphere. Since it is impossible to map something flat
+ * perfectly onto something spherical, there is distortion at the
+ * poles. This particular implementation causes the poles along the X
+ * axis to be distorted.
+ *
+ * model - pointer to initialized GLMmodel structure
+ */
+void
+glmSpheremapTexture(GLMmodel* model)
+{
+ GLMgroup* group;
+ float theta, phi, rho, x, y, z, r;
+ uint i;
+
+ assert(model);
+ assert(model->normals);
+
+ if (model->texcoords)
+ free(model->texcoords);
+ model->numtexcoords = model->numnormals;
+ model->texcoords=(float*)malloc(sizeof(float)*2*(model->numtexcoords+1));
+
+ /* do the calculations */
+ for (i = 1; i <= model->numnormals; i++) {
+ z = model->normals[3 * i + 0]; /* re-arrange for pole distortion */
+ y = model->normals[3 * i + 1];
+ x = model->normals[3 * i + 2];
+ r = sqrt((x * x) + (y * y));
+ rho = sqrt((r * r) + (z * z));
+
+ if(r == 0.0) {
+ theta = 0.0;
+ phi = 0.0;
+ } else {
+ if(z == 0.0)
+ phi = M_PI / 2.0;
+ else
+ phi = acos(z / rho);
+
+#if WE_DONT_NEED_THIS_CODE
+ if(x == 0.0)
+ theta = M_PI / 2.0; /* asin(y / r); */
+ else
+ theta = acos(x / r);
+#endif
+
+ if(y == 0.0)
+ theta = M_PI / 2.0; /* acos(x / r); */
+ else
+ theta = asin(y / r) + (M_PI / 2.0);
+ }
+
+ model->texcoords[2 * i + 0] = theta / M_PI;
+ model->texcoords[2 * i + 1] = phi / M_PI;
+ }
+
+ /* go through and put texcoord indices in all the triangles */
+ group = model->groups;
+ while(group) {
+ for (i = 0; i < group->numtriangles; i++) {
+ T(group->triangles[i]).tindices[0] = T(group->triangles[i]).nindices[0];
+ T(group->triangles[i]).tindices[1] = T(group->triangles[i]).nindices[1];
+ T(group->triangles[i]).tindices[2] = T(group->triangles[i]).nindices[2];
+ }
+ group = group->next;
+ }
+
+#if 0
+ printf("glmSpheremapTexture(): generated %d spheremap texture coordinates\n",
+ model->numtexcoords);
+#endif
+}
+
+/* glmDelete: Deletes a GLMmodel structure.
+ *
+ * model - initialized GLMmodel structure
+ */
+void
+glmDelete(GLMmodel* model)
+{
+ GLMgroup* group;
+ uint i;
+
+ assert(model);
+
+ if (model->pathname) free(model->pathname);
+ if (model->mtllibname) free(model->mtllibname);
+ if (model->vertices) free(model->vertices);
+ if (model->normals) free(model->normals);
+ if (model->texcoords) free(model->texcoords);
+ if (model->facetnorms) free(model->facetnorms);
+ if (model->triangles) free(model->triangles);
+ if (model->materials) {
+ for (i = 0; i < model->nummaterials; i++)
+ free(model->materials[i].name);
+ }
+ free(model->materials);
+ while(model->groups) {
+ group = model->groups;
+ model->groups = model->groups->next;
+ free(group->name);
+ free(group->triangles);
+ free(group);
+ }
+
+ free(model);
+}
+
+static GLMmaterial *
+glmDefaultMaterial(void)
+{
+ GLMmaterial *m = (GLMmaterial *) calloc(1, sizeof(GLMmaterial));
+
+ m->diffuse[0] = 0.75;
+ m->diffuse[1] = 0.75;
+ m->diffuse[2] = 0.75;
+ m->diffuse[3] = 1.0;
+
+ m->specular[0] = 1.0;
+ m->specular[1] = 1.0;
+ m->specular[2] = 1.0;
+ m->specular[3] = 1.0;
+
+ m->shininess = 5;
+
+ return m;
+}
+
+
+/* glmReadOBJ: Reads a model description from a Wavefront .OBJ file.
+ * Returns a pointer to the created object which should be free'd with
+ * glmDelete().
+ *
+ * filename - name of the file containing the Wavefront .OBJ format data.
+ */
+GLMmodel*
+glmReadOBJ(char* filename)
+{
+ GLMmodel* model;
+ FILE* file;
+
+ /* open the file */
+ file = fopen(filename, "r");
+ if (!file) {
+ fprintf(stderr, "glmReadOBJ() failed: can't open data file \"%s\".\n",
+ filename);
+ exit(1);
+ }
+
+#if 0
+ /* announce the model name */
+ printf("Model: %s\n", filename);
+#endif
+
+ /* allocate a new model */
+ model = (GLMmodel*)malloc(sizeof(GLMmodel));
+ model->pathname = stralloc(filename);
+ model->mtllibname = NULL;
+ model->numvertices = 0;
+ model->vertices = NULL;
+ model->numnormals = 0;
+ model->normals = NULL;
+ model->numtexcoords = 0;
+ model->texcoords = NULL;
+ model->numfacetnorms = 0;
+ model->facetnorms = NULL;
+ model->numtriangles = 0;
+ model->triangles = NULL;
+ model->nummaterials = 0;
+ model->materials = NULL;
+ model->numgroups = 0;
+ model->groups = NULL;
+ model->position[0] = 0.0;
+ model->position[1] = 0.0;
+ model->position[2] = 0.0;
+ model->scale = 1.0;
+
+ /* make a first pass through the file to get a count of the number
+ of vertices, normals, texcoords & triangles */
+ _glmFirstPass(model, file);
+
+ /* allocate memory */
+ model->vertices = (float*)malloc(sizeof(float) *
+ 3 * (model->numvertices + 1));
+ model->triangles = (GLMtriangle*)malloc(sizeof(GLMtriangle) *
+ model->numtriangles);
+ if (model->numnormals) {
+ model->normals = (float*)malloc(sizeof(float) *
+ 3 * (model->numnormals + 1));
+ }
+ if (model->numtexcoords) {
+ model->texcoords = (float*)malloc(sizeof(float) *
+ 2 * (model->numtexcoords + 1));
+ }
+
+ /* rewind to beginning of file and read in the data this pass */
+ rewind(file);
+
+ _glmSecondPass(model, file);
+
+ /* close the file */
+ fclose(file);
+
+ if (!model->materials) {
+ model->materials = glmDefaultMaterial();
+ model->nummaterials = 1;
+ }
+
+ return model;
+}
+
+/* glmWriteOBJ: Writes a model description in Wavefront .OBJ format to
+ * a file.
+ *
+ * model - initialized GLMmodel structure
+ * filename - name of the file to write the Wavefront .OBJ format data to
+ * mode - a bitwise or of values describing what is written to the file
+ * GLM_NONE - render with only vertices
+ * GLM_FLAT - render with facet normals
+ * GLM_SMOOTH - render with vertex normals
+ * GLM_TEXTURE - render with texture coords
+ * GLM_COLOR - render with colors (color material)
+ * GLM_MATERIAL - render with materials
+ * GLM_COLOR and GLM_MATERIAL should not both be specified.
+ * GLM_FLAT and GLM_SMOOTH should not both be specified.
+ */
+void
+glmWriteOBJ(GLMmodel* model, char* filename, uint mode)
+{
+ uint i;
+ FILE* file;
+ GLMgroup* group;
+
+ assert(model);
+
+ /* do a bit of warning */
+ if (mode & GLM_FLAT && !model->facetnorms) {
+ printf("glmWriteOBJ() warning: flat normal output requested "
+ "with no facet normals defined.\n");
+ mode &= ~GLM_FLAT;
+ }
+ if (mode & GLM_SMOOTH && !model->normals) {
+ printf("glmWriteOBJ() warning: smooth normal output requested "
+ "with no normals defined.\n");
+ mode &= ~GLM_SMOOTH;
+ }
+ if (mode & GLM_TEXTURE && !model->texcoords) {
+ printf("glmWriteOBJ() warning: texture coordinate output requested "
+ "with no texture coordinates defined.\n");
+ mode &= ~GLM_TEXTURE;
+ }
+ if (mode & GLM_FLAT && mode & GLM_SMOOTH) {
+ printf("glmWriteOBJ() warning: flat normal output requested "
+ "and smooth normal output requested (using smooth).\n");
+ mode &= ~GLM_FLAT;
+ }
+
+ /* open the file */
+ file = fopen(filename, "w");
+ if (!file) {
+ fprintf(stderr, "glmWriteOBJ() failed: can't open file \"%s\" to write.\n",
+ filename);
+ exit(1);
+ }
+
+ /* spit out a header */
+ fprintf(file, "# \n");
+ fprintf(file, "# Wavefront OBJ generated by GLM library\n");
+ fprintf(file, "# \n");
+ fprintf(file, "# GLM library copyright (C) 1997 by Nate Robins\n");
+ fprintf(file, "# email: ndr@pobox.com\n");
+ fprintf(file, "# www: http://www.pobox.com/~ndr\n");
+ fprintf(file, "# \n");
+
+ if (mode & GLM_MATERIAL && model->mtllibname) {
+ fprintf(file, "\nmtllib %s\n\n", model->mtllibname);
+ _glmWriteMTL(model, filename, model->mtllibname);
+ }
+
+ /* spit out the vertices */
+ fprintf(file, "\n");
+ fprintf(file, "# %d vertices\n", model->numvertices);
+ for (i = 1; i <= model->numvertices; i++) {
+ fprintf(file, "v %f %f %f\n",
+ model->vertices[3 * i + 0],
+ model->vertices[3 * i + 1],
+ model->vertices[3 * i + 2]);
+ }
+
+ /* spit out the smooth/flat normals */
+ if (mode & GLM_SMOOTH) {
+ fprintf(file, "\n");
+ fprintf(file, "# %d normals\n", model->numnormals);
+ for (i = 1; i <= model->numnormals; i++) {
+ fprintf(file, "vn %f %f %f\n",
+ model->normals[3 * i + 0],
+ model->normals[3 * i + 1],
+ model->normals[3 * i + 2]);
+ }
+ } else if (mode & GLM_FLAT) {
+ fprintf(file, "\n");
+ fprintf(file, "# %d normals\n", model->numfacetnorms);
+ for (i = 1; i <= model->numnormals; i++) {
+ fprintf(file, "vn %f %f %f\n",
+ model->facetnorms[3 * i + 0],
+ model->facetnorms[3 * i + 1],
+ model->facetnorms[3 * i + 2]);
+ }
+ }
+
+ /* spit out the texture coordinates */
+ if (mode & GLM_TEXTURE) {
+ fprintf(file, "\n");
+ fprintf(file, "# %d texcoords\n", model->numtexcoords);
+ for (i = 1; i <= model->numtexcoords; i++) {
+ fprintf(file, "vt %f %f\n",
+ model->texcoords[2 * i + 0],
+ model->texcoords[2 * i + 1]);
+ }
+ }
+
+ fprintf(file, "\n");
+ fprintf(file, "# %d groups\n", model->numgroups);
+ fprintf(file, "# %d faces (triangles)\n", model->numtriangles);
+ fprintf(file, "\n");
+
+ group = model->groups;
+ while(group) {
+ fprintf(file, "g %s\n", group->name);
+ if (mode & GLM_MATERIAL)
+ fprintf(file, "usemtl %s\n", model->materials[group->material].name);
+ for (i = 0; i < group->numtriangles; i++) {
+ if (mode & GLM_SMOOTH && mode & GLM_TEXTURE) {
+ fprintf(file, "f %d/%d/%d %d/%d/%d %d/%d/%d\n",
+ T(group->triangles[i]).vindices[0],
+ T(group->triangles[i]).nindices[0],
+ T(group->triangles[i]).tindices[0],
+ T(group->triangles[i]).vindices[1],
+ T(group->triangles[i]).nindices[1],
+ T(group->triangles[i]).tindices[1],
+ T(group->triangles[i]).vindices[2],
+ T(group->triangles[i]).nindices[2],
+ T(group->triangles[i]).tindices[2]);
+ } else if (mode & GLM_FLAT && mode & GLM_TEXTURE) {
+ fprintf(file, "f %d/%d %d/%d %d/%d\n",
+ T(group->triangles[i]).vindices[0],
+ T(group->triangles[i]).findex,
+ T(group->triangles[i]).vindices[1],
+ T(group->triangles[i]).findex,
+ T(group->triangles[i]).vindices[2],
+ T(group->triangles[i]).findex);
+ } else if (mode & GLM_TEXTURE) {
+ fprintf(file, "f %d/%d %d/%d %d/%d\n",
+ T(group->triangles[i]).vindices[0],
+ T(group->triangles[i]).tindices[0],
+ T(group->triangles[i]).vindices[1],
+ T(group->triangles[i]).tindices[1],
+ T(group->triangles[i]).vindices[2],
+ T(group->triangles[i]).tindices[2]);
+ } else if (mode & GLM_SMOOTH) {
+ fprintf(file, "f %d//%d %d//%d %d//%d\n",
+ T(group->triangles[i]).vindices[0],
+ T(group->triangles[i]).nindices[0],
+ T(group->triangles[i]).vindices[1],
+ T(group->triangles[i]).nindices[1],
+ T(group->triangles[i]).vindices[2],
+ T(group->triangles[i]).nindices[2]);
+ } else if (mode & GLM_FLAT) {
+ fprintf(file, "f %d//%d %d//%d %d//%d\n",
+ T(group->triangles[i]).vindices[0],
+ T(group->triangles[i]).findex,
+ T(group->triangles[i]).vindices[1],
+ T(group->triangles[i]).findex,
+ T(group->triangles[i]).vindices[2],
+ T(group->triangles[i]).findex);
+ } else {
+ fprintf(file, "f %d %d %d\n",
+ T(group->triangles[i]).vindices[0],
+ T(group->triangles[i]).vindices[1],
+ T(group->triangles[i]).vindices[2]);
+ }
+ }
+ fprintf(file, "\n");
+ group = group->next;
+ }
+
+ fclose(file);
+}
+
+/* glmWeld: eliminate (weld) vectors that are within an epsilon of
+ * each other.
+ *
+ * model - initialized GLMmodel structure
+ * epsilon - maximum difference between vertices
+ * ( 0.00001 is a good start for a unitized model)
+ *
+ */
+void
+glmWeld(GLMmodel* model, float epsilon)
+{
+ float* vectors;
+ float* copies;
+ uint numvectors;
+ uint i;
+
+ /* vertices */
+ numvectors = model->numvertices;
+ vectors = model->vertices;
+ copies = _glmWeldVectors(vectors, &numvectors, epsilon);
+
+ printf("glmWeld(): %d redundant vertices.\n",
+ model->numvertices - numvectors - 1);
+
+ for (i = 0; i < model->numtriangles; i++) {
+ T(i).vindices[0] = (uint)vectors[3 * T(i).vindices[0] + 0];
+ T(i).vindices[1] = (uint)vectors[3 * T(i).vindices[1] + 0];
+ T(i).vindices[2] = (uint)vectors[3 * T(i).vindices[2] + 0];
+ }
+
+ /* free space for old vertices */
+ free(vectors);
+
+ /* allocate space for the new vertices */
+ model->numvertices = numvectors;
+ model->vertices = (float*)malloc(sizeof(float) *
+ 3 * (model->numvertices + 1));
+
+ /* copy the optimized vertices into the actual vertex list */
+ for (i = 1; i <= model->numvertices; i++) {
+ model->vertices[3 * i + 0] = copies[3 * i + 0];
+ model->vertices[3 * i + 1] = copies[3 * i + 1];
+ model->vertices[3 * i + 2] = copies[3 * i + 2];
+ }
+
+ free(copies);
+}
+
+
+void
+glmReIndex(GLMmodel *model)
+{
+ uint i, j, n;
+ GLMgroup* group;
+ float *newNormals = NULL;
+ float *newTexcoords = NULL;
+ const uint numv = model->numvertices;
+
+ if (model->numnormals > 0)
+ newNormals = (float *) malloc((numv + 1) * 3 * sizeof(float));
+
+ if (model->numtexcoords > 0)
+ newTexcoords = (float *) malloc((numv + 1) * 2 * sizeof(float));
+
+ for (group = model->groups; group; group = group->next) {
+
+ n = group->numtriangles;
+
+ group->triIndexes = (uint *) malloc(n * 3 * sizeof(uint));
+
+ group->minIndex = 10000000;
+ group->maxIndex = 0;
+
+ for (i = 0; i < n; i++) {
+
+ for (j = 0; j < 3; j++) {
+ uint vindex = T(group->triangles[i]).vindices[j];
+ uint nindex = T(group->triangles[i]).nindices[j];
+ uint tindex = T(group->triangles[i]).tindices[j];
+
+ float *nrm = &model->normals[nindex * 3];
+ float *tex = &model->texcoords[tindex * 2];
+
+ if (newNormals) {
+ assert(vindex * 3 + 2 < (numv + 1) * 3);
+ newNormals[vindex * 3 + 0] = nrm[0];
+ newNormals[vindex * 3 + 1] = nrm[1];
+ newNormals[vindex * 3 + 2] = nrm[2];
+ }
+ if (newTexcoords) {
+ newTexcoords[vindex * 2 + 0] = tex[0];
+ newTexcoords[vindex * 2 + 1] = tex[1];
+ }
+
+ T(group->triangles[i]).nindices[j] = vindex;
+ T(group->triangles[i]).tindices[j] = vindex;
+
+ group->triIndexes[i * 3 + j] = vindex;
+
+ if (vindex > group->maxIndex)
+ group->maxIndex = vindex;
+ if (vindex < group->minIndex)
+ group->minIndex = vindex;
+ }
+ }
+ }
+
+ if (newNormals) {
+ free(model->normals);
+ model->normals = newNormals;
+ model->numnormals = model->numvertices;
+ }
+
+ if (newTexcoords) {
+ free(model->texcoords);
+ model->texcoords = newTexcoords;
+ model->numtexcoords = model->numvertices;
+ }
+}
+
+
+
+void
+glmPrint(const GLMmodel *model)
+{
+ uint i, j, grp, n;
+ GLMgroup* group;
+ uint totalTris = 0;
+
+ grp = 0;
+
+ printf("%u vertices\n", model->numvertices);
+ printf("%u normals\n", model->numnormals);
+ printf("%u texcoords\n", model->numtexcoords);
+
+ for (group = model->groups; group; group = group->next, grp++) {
+ printf("Group %u:\n", grp);
+ printf(" Min index %u, max index %u\n", group->minIndex, group->maxIndex);
+
+#if 0
+ if (mode & GLM_MATERIAL) {
+ glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,
+ model->materials[group->material].ambient);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,
+ model->materials[group->material].diffuse);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR,
+ model->materials[group->material].specular);
+ glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS,
+ model->materials[group->material].shininess);
+ }
+
+ if (mode & GLM_COLOR) {
+ glColor3fv(model->materials[group->material].diffuse);
+ }
+#endif
+ totalTris += group->numtriangles;
+
+ printf(" %u triangles\n", group->numtriangles);
+ n = group->numtriangles;
+ if (n > 10)
+ n = 10;
+
+ for (i = 0; i < n; i++) {
+
+ printf(" %u: vert ", i);
+ for (j = 0; j < 3; j++) {
+ printf("%u ", T(group->triangles[i]).vindices[j]);
+ }
+
+ printf(" normal ");
+ for (j = 0; j < 3; j++) {
+ printf("%u ", T(group->triangles[i]).nindices[j]);
+ }
+
+ printf(" tex ");
+ for (j = 0; j < 3; j++) {
+ printf("%u ", T(group->triangles[i]).tindices[j]);
+ }
+
+ printf("\n");
+ }
+ }
+ printf("Total tris: %u\n", totalTris);
+}
+
+
+
+#if 0
+ /* normals */
+ if (model->numnormals) {
+ numvectors = model->numnormals;
+ vectors = model->normals;
+ copies = _glmOptimizeVectors(vectors, &numvectors);
+
+ printf("glmOptimize(): %d redundant normals.\n",
+ model->numnormals - numvectors);
+
+ for (i = 0; i < model->numtriangles; i++) {
+ T(i).nindices[0] = (uint)vectors[3 * T(i).nindices[0] + 0];
+ T(i).nindices[1] = (uint)vectors[3 * T(i).nindices[1] + 0];
+ T(i).nindices[2] = (uint)vectors[3 * T(i).nindices[2] + 0];
+ }
+
+ /* free space for old normals */
+ free(vectors);
+
+ /* allocate space for the new normals */
+ model->numnormals = numvectors;
+ model->normals = (float*)malloc(sizeof(float) *
+ 3 * (model->numnormals + 1));
+
+ /* copy the optimized vertices into the actual vertex list */
+ for (i = 1; i <= model->numnormals; i++) {
+ model->normals[3 * i + 0] = copies[3 * i + 0];
+ model->normals[3 * i + 1] = copies[3 * i + 1];
+ model->normals[3 * i + 2] = copies[3 * i + 2];
+ }
+
+ free(copies);
+ }
+
+ /* texcoords */
+ if (model->numtexcoords) {
+ numvectors = model->numtexcoords;
+ vectors = model->texcoords;
+ copies = _glmOptimizeVectors(vectors, &numvectors);
+
+ printf("glmOptimize(): %d redundant texcoords.\n",
+ model->numtexcoords - numvectors);
+
+ for (i = 0; i < model->numtriangles; i++) {
+ for (j = 0; j < 3; j++) {
+ T(i).tindices[j] = (uint)vectors[3 * T(i).tindices[j] + 0];
+ }
+ }
+
+ /* free space for old texcoords */
+ free(vectors);
+
+ /* allocate space for the new texcoords */
+ model->numtexcoords = numvectors;
+ model->texcoords = (float*)malloc(sizeof(float) *
+ 2 * (model->numtexcoords + 1));
+
+ /* copy the optimized vertices into the actual vertex list */
+ for (i = 1; i <= model->numtexcoords; i++) {
+ model->texcoords[2 * i + 0] = copies[2 * i + 0];
+ model->texcoords[2 * i + 1] = copies[2 * i + 1];
+ }
+
+ free(copies);
+ }
+#endif
+
+#if 0
+ /* look for unused vertices */
+ /* look for unused normals */
+ /* look for unused texcoords */
+ for (i = 1; i <= model->numvertices; i++) {
+ for (j = 0; j < model->numtriangles; i++) {
+ if (T(j).vindices[0] == i ||
+ T(j).vindices[1] == i ||
+ T(j).vindices[1] == i)
+ break;
+ }
+ }
+#endif
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