nuclear@0: /* version 2: does not crash when there are no texture coordinates or normals */
nuclear@0: #include <stdio.h>
nuclear@0: #include <stdlib.h>
nuclear@0: #include <string.h>
nuclear@0: #include <errno.h>
nuclear@0: #include <limits.h>
nuclear@0: #include <ctype.h>
nuclear@0: #include "objfile.h"
nuclear@0: 
nuclear@0: #define INVALID_IDX		INT_MIN
nuclear@0: 
nuclear@0: struct objfile {
nuclear@0: 	float *verts, *normals, *texcoords;
nuclear@0: 	int num_faces;
nuclear@0: };
nuclear@0: 
nuclear@0: struct vec3 {
nuclear@0: 	float x, y, z;
nuclear@0: };
nuclear@0: 
nuclear@0: struct face {
nuclear@0: 	int vidx[4];
nuclear@0: 	int nidx[4];
nuclear@0: 	int tidx[4];
nuclear@0: };
nuclear@0: 
nuclear@0: static int objf_read(struct objfile *obj, FILE *fp, const char *fname);
nuclear@0: static int count_elem(FILE *fp, const char *elem);
nuclear@0: static char *strip(char *s);
nuclear@0: static int mkface(char *line, struct face *face);
nuclear@0: static int parse_face(char *s, int *vidx, int *nidx, int *tidx);
nuclear@0: static int is_int(const char *str);
nuclear@0: 
nuclear@0: 
nuclear@0: struct objfile *objf_load(const char *fname)
nuclear@0: {
nuclear@0: 	FILE *fp;
nuclear@0: 	struct objfile *obj;
nuclear@0: 
nuclear@0: 	if(!(fp = fopen(fname, "rb"))) {
nuclear@0: 		fprintf(stderr, "objf_load: failed to open file: %s: %s\n", fname, strerror(errno));
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	if(!(obj = malloc(sizeof *obj))) {
nuclear@0: 		perror("failed to allocate objfile structure\n");
nuclear@0: 		fclose(fp);
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	if(objf_read(obj, fp, fname) == -1) {
nuclear@0: 		free(obj);
nuclear@0: 		obj = 0;
nuclear@0: 	}
nuclear@0: 	fclose(fp);
nuclear@0: 	return obj;
nuclear@0: }
nuclear@0: 
nuclear@0: void objf_free(struct objfile *obj)
nuclear@0: {
nuclear@0: 	if(obj) {
nuclear@0: 		free(obj->verts);
nuclear@0: 		free(obj->normals);
nuclear@0: 		free(obj->texcoords);
nuclear@0: 		free(obj);
nuclear@0: 	}
nuclear@0: }
nuclear@0: 
nuclear@0: int objf_vertex_count(struct objfile *obj)
nuclear@0: {
nuclear@0: 	return obj->num_faces * 3;
nuclear@0: }
nuclear@0: 
nuclear@0: int objf_face_count(struct objfile *obj)
nuclear@0: {
nuclear@0: 	return obj->num_faces;
nuclear@0: }
nuclear@0: 
nuclear@0: float *objf_vertices(struct objfile *obj)
nuclear@0: {
nuclear@0: 	return obj->verts;
nuclear@0: }
nuclear@0: 
nuclear@0: float *objf_normals(struct objfile *obj)
nuclear@0: {
nuclear@0: 	return obj->normals;
nuclear@0: }
nuclear@0: 
nuclear@0: float *objf_texcoords(struct objfile *obj)
nuclear@0: {
nuclear@0: 	return obj->texcoords;
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: float *objf_vertex(struct objfile *obj, int idx)
nuclear@0: {
nuclear@0: 	return obj->verts + idx * 3;
nuclear@0: }
nuclear@0: 
nuclear@0: float *objf_normal(struct objfile *obj, int idx)
nuclear@0: {
nuclear@0: 	return obj->normals + idx * 3;
nuclear@0: }
nuclear@0: 
nuclear@0: float *objf_texcoord(struct objfile *obj, int idx)
nuclear@0: {
nuclear@0: 	return obj->texcoords + idx * 2;
nuclear@0: }
nuclear@0: 
nuclear@0: static int objf_read(struct objfile *obj, FILE *fp, const char *fname)
nuclear@0: {
nuclear@0: 	int i, j, res = -1;
nuclear@0: 	int vcount, ncount, tcount, fcount;
nuclear@0: 	int num_verts;
nuclear@0: 	struct vec3 *varr, *narr, *tarr;
nuclear@0: 	struct vec3 *vptr, *nptr, *tptr;
nuclear@0: 	struct vec3 dummy_vec = {0, 0, 0};
nuclear@0: 	struct face *faces, *fptr;
nuclear@0: 	float *vdest, *ndest, *tdest;
nuclear@0: 	char buf[512];
nuclear@0: 
nuclear@0: 	vcount = count_elem(fp, "v");
nuclear@0: 	rewind(fp);
nuclear@0: 	ncount = count_elem(fp, "vn");
nuclear@0: 	rewind(fp);
nuclear@0: 	tcount = count_elem(fp, "vt");
nuclear@0: 	rewind(fp);
nuclear@0: 	fcount = count_elem(fp, "f");
nuclear@0: 	rewind(fp);
nuclear@0: 
nuclear@0: 	obj->num_faces = fcount;
nuclear@0: 
nuclear@0: 	if(!vcount || !fcount) {
nuclear@0: 		fprintf(stderr, "invalid or corrupted obj file: %s\n", fname);
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	printf("Reading obj file: %s (%d vertices, %d faces)\n", fname, vcount, fcount);
nuclear@0: 
nuclear@0: 	vptr = varr = malloc(vcount * sizeof *varr);
nuclear@0: 	nptr = narr = ncount ? malloc(ncount * sizeof *narr) : &dummy_vec;
nuclear@0: 	tptr = tarr = tcount ? malloc(tcount * sizeof *tarr) : &dummy_vec;
nuclear@0: 	fptr = faces = malloc(fcount * sizeof *faces);
nuclear@0: 
nuclear@0: 	if(!varr || !narr || !tarr || !faces) {
nuclear@0: 		perror("can't allocate enough memory for the geometry");
nuclear@0: 		goto cleanup;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	while(fgets(buf, sizeof buf, fp)) {
nuclear@0: 		char *line;
nuclear@0: 
nuclear@0: 		if(!(line = strip(buf)) || *line == '#') {
nuclear@0: 			continue;	/* ignore empty lines and comments */
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		if(sscanf(line, "v %f %f %f", &vptr->x, &vptr->y, &vptr->z) == 3) {
nuclear@0: 			vptr++;
nuclear@0: 		} else if(sscanf(line, "vn %f %f %f", &nptr->x, &nptr->y, &nptr->z) == 3) {
nuclear@0: 			nptr++;
nuclear@0: 		} else if(sscanf(line, "vt %f %f", &tptr->x, &tptr->y) == 2) {
nuclear@0: 			tptr++;
nuclear@0: 		} else if(mkface(line, fptr) == 0) {
nuclear@0: 			fptr++;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	/* now go forth and create the straight-up 3-vert-per-face vertex arrays */
nuclear@0: 	num_verts = obj->num_faces * 3;
nuclear@0: 
nuclear@0: 	vdest = obj->verts = malloc(num_verts * 3 * sizeof *obj->verts);
nuclear@0: 	ndest = obj->normals = malloc(num_verts * 3 * sizeof *obj->normals);
nuclear@0: 	tdest = obj->texcoords = malloc(num_verts * 2 * sizeof *obj->texcoords);
nuclear@0: 
nuclear@0: 	if(!obj->verts || !obj->normals || !obj->texcoords) {
nuclear@0: 		free(obj->verts);
nuclear@0: 		free(obj->normals);
nuclear@0: 		goto cleanup;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	/* for all faces */
nuclear@0: 	for(i=0; i<fcount; i++) {
nuclear@0: 		/* for the 3 vertices of each face */
nuclear@0: 		for(j=0; j<3; j++) {
nuclear@0: 			*vdest++ = varr[faces[i].vidx[j]].x;
nuclear@0: 			*vdest++ = varr[faces[i].vidx[j]].y;
nuclear@0: 			*vdest++ = varr[faces[i].vidx[j]].z;
nuclear@0: 
nuclear@0: 			*ndest++ = narr[faces[i].nidx[j]].x;
nuclear@0: 			*ndest++ = narr[faces[i].nidx[j]].y;
nuclear@0: 			*ndest++ = narr[faces[i].nidx[j]].z;
nuclear@0: 
nuclear@0: 			*tdest++ = tarr[faces[i].tidx[j]].x;
nuclear@0: 			*tdest++ = tarr[faces[i].tidx[j]].y;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	res = 0;	/* success */
nuclear@0: 
nuclear@0: cleanup:
nuclear@0: 	free(varr);
nuclear@0: 	if(narr != &dummy_vec) {
nuclear@0: 		free(narr);
nuclear@0: 	}
nuclear@0: 	if(tarr != &dummy_vec) {
nuclear@0: 		free(tarr);
nuclear@0: 	}
nuclear@0: 	free(faces);
nuclear@0: 	return res;
nuclear@0: }
nuclear@0: 
nuclear@0: static int count_elem(FILE *fp, const char *elem)
nuclear@0: {
nuclear@0: 	int count = 0;
nuclear@0: 	char buf[512];
nuclear@0: 
nuclear@0: 	while(fgets(buf, sizeof buf, fp)) {
nuclear@0: 		if(buf[0] == elem[0] && (!elem[1] || buf[1] == elem[1])) {
nuclear@0: 			count++;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	return count;
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: static char *strip(char *s)
nuclear@0: {
nuclear@0: 	while(*s && isspace(*s)) {
nuclear@0: 		s++;
nuclear@0: 	}
nuclear@0: 	return s;
nuclear@0: }
nuclear@0: 
nuclear@0: static int mkface(char *s, struct face *face)
nuclear@0: {
nuclear@0: 	int nverts;
nuclear@0: 
nuclear@0: 	if(s[0] != 'f') {
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	if((nverts = parse_face(s + 2, face->vidx, face->nidx, face->tidx)) == -1) {
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 	if(nverts > 3) {
nuclear@0: 		fprintf(stderr, "warning face with more than 3 vertices found\n");
nuclear@0: 	}
nuclear@0: 	return 0;
nuclear@0: }
nuclear@0: 
nuclear@0: #define SEP	" \t\v\n\r"
nuclear@0: /* returns the number of vertices on this face, or -1 on error. */
nuclear@0: static int parse_face(char *s, int *vidx, int *nidx, int *tidx)
nuclear@0: {
nuclear@0: 	int i, num_verts = 0;
nuclear@0: 	char *tok[] = {0, 0, 0, 0};
nuclear@0: 	char *subtok;
nuclear@0: 
nuclear@0: 	for(i=0; i<4; i++) {
nuclear@0: 		if((!(tok[i] = strtok(i == 0 ? s : 0, SEP)) || !is_int(tok[i]))) {
nuclear@0: 			if(i < 3) return -1;
nuclear@0: 		} else {
nuclear@0: 			num_verts++;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	for(i=0; i<4; i++) {
nuclear@0: 		subtok = tok[i];
nuclear@0: 		if(!subtok || !*subtok || !is_int(subtok)) {
nuclear@0: 			if(i < 3) {
nuclear@0: 				return -1;
nuclear@0: 			}
nuclear@0: 			vidx[i] = INVALID_IDX;
nuclear@0: 		} else {
nuclear@0: 			vidx[i] = atoi(subtok);
nuclear@0: 			if(vidx[i] > 0) vidx[i]--;	/* convert to 0-based */
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		while(subtok && *subtok && *subtok != '/') {
nuclear@0: 			subtok++;
nuclear@0: 		}
nuclear@0: 		if(subtok && *subtok && *++subtok && is_int(subtok)) {
nuclear@0: 			tidx[i] = atoi(subtok);
nuclear@0: 			if(tidx[i] > 0) tidx[i]--;	/* convert to 0-based */
nuclear@0: 		} else {
nuclear@0: 			tidx[i] = 0;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		while(subtok && *subtok && *subtok != '/') {
nuclear@0: 			subtok++;
nuclear@0: 		}
nuclear@0: 		if(subtok && *subtok && *++subtok && is_int(subtok)) {
nuclear@0: 			nidx[i] = atoi(subtok);
nuclear@0: 			if(nidx[i] > 0) nidx[i]--;	/* convert to 0-based */
nuclear@0: 		} else {
nuclear@0: 			nidx[i] = 0;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	return num_verts;
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: static int is_int(const char *str)
nuclear@0: {
nuclear@0: 	return isdigit(str[0]) ||
nuclear@0: 		(str[0] == '-' && isdigit(str[1])) ||
nuclear@0: 		(str[0] == '+' && isdigit(str[1]));
nuclear@0: }