1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/scene.cc	Wed Aug 11 04:30:35 2010 +0100
     1.3 @@ -0,0 +1,755 @@
     1.4 +#include <stdio.h>
     1.5 +#include <stdlib.h>
     1.6 +#include <string.h>
     1.7 +#include <math.h>
     1.8 +#include <errno.h>
     1.9 +#include <limits.h>
    1.10 +#include <string>
    1.11 +#include <vector>
    1.12 +#include <map>
    1.13 +#include "scene.h"
    1.14 +
    1.15 +#ifndef PATH_MAX
    1.16 +#define PATH_MAX	512
    1.17 +#endif
    1.18 +
    1.19 +using namespace std;
    1.20 +
    1.21 +#define COMMANDS	\
    1.22 +	CMD(V),			\
    1.23 +	CMD(VN),		\
    1.24 +	CMD(VT),		\
    1.25 +	CMD(F),			\
    1.26 +	CMD(O),			\
    1.27 +	CMD(G),			\
    1.28 +	CMD(MTLLIB),	\
    1.29 +	CMD(USEMTL),	\
    1.30 +	CMD(NEWMTL),	\
    1.31 +	CMD(KA),		\
    1.32 +	CMD(KD),		\
    1.33 +	CMD(KS),		\
    1.34 +	CMD(KR),		\
    1.35 +	CMD(NS),		\
    1.36 +	CMD(NI),		\
    1.37 +	CMD(D),			\
    1.38 +	CMD(TR),		\
    1.39 +	CMD(MAP_KD),	\
    1.40 +	CMD(MAP_KS),	\
    1.41 +	CMD(MAP_NS),	\
    1.42 +	CMD(MAP_D),		\
    1.43 +	CMD(REFL),		\
    1.44 +	CMD(BUMP)
    1.45 +
    1.46 +#define CMD(x)	CMD_##x
    1.47 +enum {
    1.48 +	COMMANDS,
    1.49 +	CMD_UNK
    1.50 +};
    1.51 +#undef CMD
    1.52 +
    1.53 +#define CMD(x)	#x
    1.54 +static const char *cmd_names[] = {
    1.55 +	COMMANDS,
    1.56 +	0
    1.57 +};
    1.58 +#undef CMD
    1.59 +
    1.60 +struct Vector3 {
    1.61 +	float x, y, z;
    1.62 +
    1.63 +	Vector3() { x = y = z = 0.0; }
    1.64 +	Vector3(float a, float b, float c) { x = a; y = b; z = c; }
    1.65 +
    1.66 +	void normalize() { float len = sqrt(x * x + y * y + z * z); x /= len; y /= len; z /= len; }
    1.67 +};
    1.68 +
    1.69 +struct Vector2 {
    1.70 +	float x, y;
    1.71 +
    1.72 +	Vector2() { x = y = 0.0; }
    1.73 +	Vector2(float a, float b) { x = a; y = b; }
    1.74 +};
    1.75 +
    1.76 +struct obj_face {
    1.77 +	int elem;
    1.78 +	int v[4], n[4], t[4];
    1.79 +};
    1.80 +
    1.81 +struct obj_file {
    1.82 +	string cur_obj, cur_mat;
    1.83 +	vector<Vector3> v, vn, vt;
    1.84 +	vector<obj_face> f;
    1.85 +};
    1.86 +
    1.87 +struct obj_mat {
    1.88 +	string name;		// newmtl <name>
    1.89 +	Vector3 ambient, diffuse, specular;	// Ka, Kd, Ks
    1.90 +	float shininess;	// Ns
    1.91 +	float ior;			// Ni
    1.92 +	float alpha;		// d, Tr
    1.93 +	float refl;			// Kr (my extesnsion)
    1.94 +
    1.95 +	string tex_dif, tex_spec, tex_shin, tex_alpha;	// map_Kd, map_Ks, map_Ns, map_d
    1.96 +	string tex_refl;	// refl -type sphere|cube file
    1.97 +	string tex_bump;	// bump
    1.98 +
    1.99 +	obj_mat() { reset(); }
   1.100 +
   1.101 +	void reset() {
   1.102 +		ambient = diffuse = Vector3(0.5, 0.5, 0.5);
   1.103 +		specular = Vector3(0.0, 0.0, 0.0);
   1.104 +		name = tex_dif = tex_spec = tex_shin = tex_alpha = tex_refl = tex_bump = "";
   1.105 +		shininess = 0;
   1.106 +		ior = alpha = 1;
   1.107 +		refl = 0.0;
   1.108 +	}
   1.109 +};
   1.110 +
   1.111 +static bool read_materials(FILE *fp, vector<obj_mat> *vmtl);
   1.112 +static Mesh *cons_mesh(obj_file *obj);
   1.113 +
   1.114 +static int get_cmd(char *str);
   1.115 +static bool is_int(const char *str);
   1.116 +static bool is_float(const char *str);
   1.117 +static bool parse_vec(Vector3 *vec);
   1.118 +static bool parse_color(Vector3 *col);
   1.119 +static bool parse_face(obj_face *face);
   1.120 +static const char *parse_map();
   1.121 +
   1.122 +static bool find_file(char *res, int sz, const char *fname, const char *path = ".", const char *mode = "rb");
   1.123 +static const char *dirname(const char *str);
   1.124 +
   1.125 +static Vector3 operator -(const Vector3 &a, const Vector3 &b);
   1.126 +static Vector3 cross(const Vector3 &a, const Vector3 &b);
   1.127 +
   1.128 +static map<string, int> matnames;
   1.129 +
   1.130 +
   1.131 +#define FEQ(a, b)	(fabs((a) - (b)) < 1e-8)
   1.132 +bool Face::operator ==(const Face &f) const
   1.133 +{
   1.134 +	for(int i=0; i<3; i++) {
   1.135 +		for(int j=0; j<3; j++) {
   1.136 +			if(!FEQ(v[i].pos[j], f.v[i].pos[j])) {
   1.137 +				return false;
   1.138 +			}
   1.139 +			if(!FEQ(v[i].normal[j], f.v[i].normal[j])) {
   1.140 +				return false;
   1.141 +			}
   1.142 +		}
   1.143 +		if(!FEQ(normal[i], f.normal[i])) {
   1.144 +			return false;
   1.145 +		}
   1.146 +	}
   1.147 +	return true;
   1.148 +}
   1.149 +
   1.150 +bool Scene::add_mesh(Mesh *m)
   1.151 +{
   1.152 +	// make sure triangles have material ids
   1.153 +	for(size_t i=0; i<m->faces.size(); i++) {
   1.154 +		m->faces[i].matid = m->matid;
   1.155 +	}
   1.156 +	meshes.push_back(m);
   1.157 +	return true;
   1.158 +}
   1.159 +
   1.160 +int Scene::get_num_meshes() const
   1.161 +{
   1.162 +	return (int)meshes.size();
   1.163 +}
   1.164 +
   1.165 +int Scene::get_num_faces() const
   1.166 +{
   1.167 +	int num_faces = 0;
   1.168 +	for(size_t i=0; i<meshes.size(); i++) {
   1.169 +		num_faces += meshes[i]->faces.size();
   1.170 +	}
   1.171 +	return num_faces;
   1.172 +}
   1.173 +
   1.174 +int Scene::get_num_materials() const
   1.175 +{
   1.176 +	return (int)matlib.size();
   1.177 +}
   1.178 +
   1.179 +Material *Scene::get_materials()
   1.180 +{
   1.181 +	if(matlib.empty()) {
   1.182 +		return 0;
   1.183 +	}
   1.184 +	return &matlib[0];
   1.185 +}
   1.186 +
   1.187 +const Material *Scene::get_materials() const
   1.188 +{
   1.189 +	if(matlib.empty()) {
   1.190 +		return 0;
   1.191 +	}
   1.192 +	return &matlib[0];
   1.193 +}
   1.194 +
   1.195 +
   1.196 +#define INVALID_IDX		INT_MIN
   1.197 +
   1.198 +#define SEP		" \t\n\r\v"
   1.199 +#define BUF_SZ	512
   1.200 +
   1.201 +bool Scene::load(const char *fname)
   1.202 +{
   1.203 +	FILE *fp;
   1.204 +
   1.205 +	if(!(fp = fopen(fname, "rb"))) {
   1.206 +		fprintf(stderr, "failed to open %s: %s\n", fname, strerror(errno));
   1.207 +		return false;
   1.208 +	}
   1.209 +
   1.210 +	bool res = load(fp);
   1.211 +	fclose(fp);
   1.212 +	return res;
   1.213 +}
   1.214 +
   1.215 +bool Scene::load(FILE *fp)
   1.216 +{
   1.217 +	static int seq;
   1.218 +	char cur_name[16];
   1.219 +
   1.220 +	obj_file obj;
   1.221 +
   1.222 +	sprintf(cur_name, "default%02d.obj", seq++);
   1.223 +	obj.cur_obj = cur_name;
   1.224 +
   1.225 +	int prev_cmd = 0, obj_added = 0;
   1.226 +	for(;;) {
   1.227 +		Vector3 vec;
   1.228 +		obj_face face;
   1.229 +
   1.230 +		char line[BUF_SZ];
   1.231 +		fgets(line, sizeof line, fp);
   1.232 +		if(feof(fp)) {
   1.233 +			break;
   1.234 +		}
   1.235 +
   1.236 +		char *tok;
   1.237 +		if(!(tok = strtok(line, SEP))) {
   1.238 +			continue; // ignore empty lines
   1.239 +		}
   1.240 +
   1.241 +		int cmd;
   1.242 +		if((cmd = get_cmd(tok)) == -1) {
   1.243 +			continue; // ignore unknown commands ...
   1.244 +		}
   1.245 +
   1.246 +		switch(cmd) {
   1.247 +		case CMD_V:
   1.248 +			if(!parse_vec(&vec)) {
   1.249 +				continue;
   1.250 +			}
   1.251 +			obj.v.push_back(vec);
   1.252 +			break;
   1.253 +
   1.254 +		case CMD_VN:
   1.255 +			if(!parse_vec(&vec)) {
   1.256 +				continue;
   1.257 +			}
   1.258 +			obj.vn.push_back(vec);
   1.259 +			break;
   1.260 +
   1.261 +		case CMD_VT:
   1.262 +			if(!parse_vec(&vec)) {
   1.263 +				continue;
   1.264 +			}
   1.265 +			vec.y = 1.0 - vec.y;
   1.266 +			obj.vt.push_back(vec);
   1.267 +			break;
   1.268 +
   1.269 +		case CMD_O:
   1.270 +		case CMD_G:
   1.271 +			if(prev_cmd == CMD_O || prev_cmd == CMD_G) {
   1.272 +				break;	// just in case we've got both of them in a row
   1.273 +			}
   1.274 +			/* if we have any previous data, group them up, add the object
   1.275 +			 * and continue with the new one...
   1.276 +			 */
   1.277 +			if(!obj.f.empty()) {
   1.278 +				Mesh *mesh = cons_mesh(&obj);
   1.279 +				mesh->matid = matnames[obj.cur_mat];
   1.280 +				add_mesh(mesh);
   1.281 +				obj_added++;
   1.282 +
   1.283 +				obj.f.clear();	// clean the face list
   1.284 +			}
   1.285 +			if((tok = strtok(0, SEP))) {
   1.286 +				obj.cur_obj = tok;
   1.287 +			} else {
   1.288 +				sprintf(cur_name, "default%02d.obj", seq++);
   1.289 +				obj.cur_obj = cur_name;
   1.290 +			}
   1.291 +			break;
   1.292 +
   1.293 +		case CMD_MTLLIB:
   1.294 +			if((tok = strtok(0, SEP))) {
   1.295 +				char path[PATH_MAX];
   1.296 +
   1.297 +				sprintf(path, ".:%s", dirname(tok));
   1.298 +				if(!find_file(path, PATH_MAX, tok, path)) {
   1.299 +					fprintf(stderr, "material library not found: %s\n", tok);
   1.300 +					continue;
   1.301 +				}
   1.302 +
   1.303 +				FILE *mfile;
   1.304 +				if(!(mfile = fopen(path, "rb"))) {
   1.305 +					fprintf(stderr, "failed to open material library: %s\n", path);
   1.306 +					continue;
   1.307 +				}
   1.308 +
   1.309 +				// load all materials of the mtl file into a vector
   1.310 +				vector<obj_mat> vmtl;
   1.311 +				if(!read_materials(mfile, &vmtl)) {
   1.312 +					continue;
   1.313 +				}
   1.314 +				fclose(mfile);
   1.315 +
   1.316 +				// and add them all to the scene
   1.317 +				for(size_t i=0; i<vmtl.size(); i++) {
   1.318 +					Material mat;
   1.319 +
   1.320 +					mat.kd[0] = vmtl[i].diffuse.x;
   1.321 +					mat.kd[1] = vmtl[i].diffuse.y;
   1.322 +					mat.kd[2] = vmtl[i].diffuse.z;
   1.323 +
   1.324 +					mat.ks[0] = vmtl[i].specular.x;
   1.325 +					mat.ks[1] = vmtl[i].specular.y;
   1.326 +					mat.ks[2] = vmtl[i].specular.z;
   1.327 +
   1.328 +					mat.kt = 1.0 - vmtl[i].alpha;
   1.329 +					mat.kr = vmtl[i].refl;
   1.330 +					mat.spow = vmtl[i].shininess;
   1.331 +
   1.332 +					matlib.push_back(mat);
   1.333 +					matnames[vmtl[i].name] = i;
   1.334 +				}
   1.335 +			}
   1.336 +			break;
   1.337 +
   1.338 +		case CMD_USEMTL:
   1.339 +			if((tok = strtok(0, SEP))) {
   1.340 +				obj.cur_mat = tok;
   1.341 +			} else {
   1.342 +				obj.cur_mat = "";
   1.343 +			}
   1.344 +			break;
   1.345 +
   1.346 +		case CMD_F:
   1.347 +			if(!parse_face(&face)) {
   1.348 +				continue;
   1.349 +			}
   1.350 +
   1.351 +			// convert negative indices to regular indices
   1.352 +			for(int i=0; i<4; i++) {
   1.353 +				if(face.v[i] < 0 && face.v[i] != INVALID_IDX) {
   1.354 +					face.v[i] = obj.v.size() + face.v[i];
   1.355 +				}
   1.356 +				if(face.n[i] < 0 && face.n[i] != INVALID_IDX) {
   1.357 +					face.n[i] = obj.vn.size() + face.n[i];
   1.358 +				}
   1.359 +				if(face.t[i] < 0 && face.t[i] != INVALID_IDX) {
   1.360 +					face.t[i] = obj.vt.size() + face.t[i];
   1.361 +				}
   1.362 +			}
   1.363 +
   1.364 +			// break quads into triangles if needed
   1.365 +			obj.f.push_back(face);
   1.366 +			if(face.elem == 4) {
   1.367 +				face.v[1] = face.v[2];
   1.368 +				face.n[1] = face.n[2];
   1.369 +				face.t[1] = face.t[2];
   1.370 +
   1.371 +				face.v[2] = face.v[3];
   1.372 +				face.n[2] = face.n[3];
   1.373 +				face.t[2] = face.t[3];
   1.374 +
   1.375 +				obj.f.push_back(face);
   1.376 +			}
   1.377 +			break;
   1.378 +
   1.379 +		default:
   1.380 +			break;	// ignore unknown commands
   1.381 +		}
   1.382 +
   1.383 +		prev_cmd = cmd;
   1.384 +	}
   1.385 +
   1.386 +	// reached end of file...
   1.387 +	if(!obj.f.empty()) {
   1.388 +		Mesh *mesh = cons_mesh(&obj);
   1.389 +		mesh->matid = matnames[obj.cur_mat];
   1.390 +		add_mesh(mesh);
   1.391 +		obj_added++;
   1.392 +	}
   1.393 +
   1.394 +	return obj_added > 0;
   1.395 +}
   1.396 +
   1.397 +static Mesh *cons_mesh(obj_file *obj)
   1.398 +{
   1.399 +	Mesh *mesh;
   1.400 +
   1.401 +	// need at least one of each element
   1.402 +	bool added_norm = false, added_tc = false;
   1.403 +	if(obj->vn.empty()) {
   1.404 +		obj->vn.push_back(Vector3(0, 0, 0));
   1.405 +		added_norm = true;
   1.406 +	}
   1.407 +	if(obj->vt.empty()) {
   1.408 +		obj->vt.push_back(Vector3(0, 0, 0));
   1.409 +		added_tc = true;
   1.410 +	}
   1.411 +
   1.412 +	mesh = new Mesh;
   1.413 +
   1.414 +	for(size_t i=0; i<obj->f.size(); i++) {
   1.415 +		Face face;
   1.416 +		Vector3 v[3];
   1.417 +
   1.418 +		for(int j=0; j<3; j++) {
   1.419 +			obj_face *f = &obj->f[i];
   1.420 +
   1.421 +			face.v[j].pos[0] = v[j].x = obj->v[f->v[j]].x;
   1.422 +			face.v[j].pos[1] = v[j].y = obj->v[f->v[j]].y;
   1.423 +			face.v[j].pos[2] = v[j].z = obj->v[f->v[j]].z;
   1.424 +			face.v[j].pos[3] = 0.0;
   1.425 +
   1.426 +			int nidx = f->n[j] < 0 ? 0 : f->n[j];
   1.427 +			face.v[j].normal[0] = obj->vn[nidx].x;
   1.428 +			face.v[j].normal[1] = obj->vn[nidx].y;
   1.429 +			face.v[j].normal[2] = obj->vn[nidx].z;
   1.430 +			face.v[j].normal[3] = 0.0;
   1.431 +
   1.432 +			int tidx = f->t[j] < 0 ? 0 : f->t[j];
   1.433 +			face.v[j].tex[0] = obj->vt[tidx].x;
   1.434 +			face.v[j].tex[1] = obj->vt[tidx].y;
   1.435 +		}
   1.436 +
   1.437 +		Vector3 a = v[1] - v[0];
   1.438 +		Vector3 b = v[2] - v[0];
   1.439 +		Vector3 n = cross(a, b);
   1.440 +		n.normalize();
   1.441 +
   1.442 +		face.normal[0] = n.x;
   1.443 +		face.normal[1] = n.y;
   1.444 +		face.normal[2] = n.z;
   1.445 +		face.normal[3] = 0.0;
   1.446 +
   1.447 +		mesh->faces.push_back(face);
   1.448 +	}
   1.449 +
   1.450 +	if(added_norm) {
   1.451 +		obj->vn.pop_back();
   1.452 +	}
   1.453 +	if(added_tc) {
   1.454 +		obj->vt.pop_back();
   1.455 +	}
   1.456 +
   1.457 +	return mesh;
   1.458 +}
   1.459 +
   1.460 +static bool read_materials(FILE *fp, vector<obj_mat> *vmtl)
   1.461 +{
   1.462 +	obj_mat mat;
   1.463 +
   1.464 +	for(;;) {
   1.465 +		char line[BUF_SZ];
   1.466 +		fgets(line, sizeof line, fp);
   1.467 +		if(feof(fp)) {
   1.468 +			break;
   1.469 +		}
   1.470 +
   1.471 +		char *tok;
   1.472 +		if(!(tok = strtok(line, SEP))) {
   1.473 +			continue;
   1.474 +		}
   1.475 +
   1.476 +		int cmd;
   1.477 +		if((cmd = get_cmd(tok)) == -1) {
   1.478 +			continue;
   1.479 +		}
   1.480 +
   1.481 +		switch(cmd) {
   1.482 +		case CMD_NEWMTL:
   1.483 +			// add the previous material, and start a new one
   1.484 +			if(mat.name.length() > 0) {
   1.485 +				printf("Adding material: %s\n", mat.name.c_str());
   1.486 +				vmtl->push_back(mat);
   1.487 +				mat.reset();
   1.488 +			}
   1.489 +			if((tok = strtok(0, SEP))) {
   1.490 +				mat.name = tok;
   1.491 +			}
   1.492 +			break;
   1.493 +
   1.494 +		case CMD_KA:
   1.495 +			parse_color(&mat.ambient);
   1.496 +			break;
   1.497 +
   1.498 +		case CMD_KD:
   1.499 +			parse_color(&mat.diffuse);
   1.500 +			break;
   1.501 +
   1.502 +		case CMD_KS:
   1.503 +			parse_color(&mat.specular);
   1.504 +			break;
   1.505 +
   1.506 +		case CMD_KR:
   1.507 +			if((tok = strtok(0, SEP)) && is_float(tok)) {
   1.508 +				mat.refl = atof(tok);
   1.509 +			}
   1.510 +			break;
   1.511 +
   1.512 +		case CMD_NS:
   1.513 +			if((tok = strtok(0, SEP)) && is_float(tok)) {
   1.514 +				mat.shininess = atof(tok);
   1.515 +			}
   1.516 +			break;
   1.517 +
   1.518 +		case CMD_NI:
   1.519 +			if((tok = strtok(0, SEP)) && is_float(tok)) {
   1.520 +				mat.ior = atof(tok);
   1.521 +			}
   1.522 +			break;
   1.523 +
   1.524 +		case CMD_D:
   1.525 +		case CMD_TR:
   1.526 +			{
   1.527 +				Vector3 c;
   1.528 +				if(parse_color(&c)) {
   1.529 +					mat.alpha = cmd == CMD_D ? c.x : 1.0 - c.x;
   1.530 +				}
   1.531 +			}
   1.532 +			break;
   1.533 +
   1.534 +		case CMD_MAP_KD:
   1.535 +			mat.tex_dif = parse_map();
   1.536 +			break;
   1.537 +
   1.538 +		default:
   1.539 +			break;
   1.540 +		}
   1.541 +	}
   1.542 +
   1.543 +	if(mat.name.length() > 0) {
   1.544 +		printf("Adding material: %s\n", mat.name.c_str());
   1.545 +		vmtl->push_back(mat);
   1.546 +	}
   1.547 +	return true;
   1.548 +}
   1.549 +
   1.550 +static int get_cmd(char *str)
   1.551 +{
   1.552 +	char *s = str;
   1.553 +	while((*s = toupper(*s))) s++;
   1.554 +
   1.555 +	for(int i=0; cmd_names[i]; i++) {
   1.556 +		if(strcmp(str, cmd_names[i]) == 0) {
   1.557 +			return i;
   1.558 +		}
   1.559 +	}
   1.560 +	return CMD_UNK;
   1.561 +}
   1.562 +
   1.563 +static bool is_int(const char *str)
   1.564 +{
   1.565 +	char *tmp;
   1.566 +	strtol(str, &tmp, 10);
   1.567 +	return tmp != str;
   1.568 +}
   1.569 +
   1.570 +static bool is_float(const char *str)
   1.571 +{
   1.572 +	char *tmp;
   1.573 +	strtod(str, &tmp);
   1.574 +	return tmp != str;
   1.575 +}
   1.576 +
   1.577 +static bool parse_vec(Vector3 *vec)
   1.578 +{
   1.579 +	for(int i=0; i<3; i++) {
   1.580 +		char *tok;
   1.581 +
   1.582 +		if(!(tok = strtok(0, SEP)) || !is_float(tok)) {
   1.583 +			if(i < 2) {
   1.584 +				return false;
   1.585 +			}
   1.586 +			vec->z = 0.0;
   1.587 +		} else {
   1.588 +			float v = atof(tok);
   1.589 +
   1.590 +			switch(i) {
   1.591 +			case 0:
   1.592 +				vec->x = v;
   1.593 +				break;
   1.594 +			case 1:
   1.595 +				vec->y = v;
   1.596 +				break;
   1.597 +			case 2:
   1.598 +				vec->z = v;
   1.599 +				break;
   1.600 +			}
   1.601 +		}
   1.602 +	}
   1.603 +	return true;
   1.604 +}
   1.605 +
   1.606 +static bool parse_color(Vector3 *col)
   1.607 +{
   1.608 +	for(int i=0; i<3; i++) {
   1.609 +		char *tok;
   1.610 +
   1.611 +		if(!(tok = strtok(0, SEP)) || !is_float(tok)) {
   1.612 +			col->y = col->z = col->x;
   1.613 +			return i > 0 ? true : false;
   1.614 +		}
   1.615 +
   1.616 +		float v = atof(tok);
   1.617 +		switch(i) {
   1.618 +		case 0:
   1.619 +			col->x = v;
   1.620 +			break;
   1.621 +		case 1:
   1.622 +			col->y = v;
   1.623 +			break;
   1.624 +		case 2:
   1.625 +			col->z = v;
   1.626 +			break;
   1.627 +		}
   1.628 +	}
   1.629 +	return true;
   1.630 +}
   1.631 +
   1.632 +static bool parse_face(obj_face *face)
   1.633 +{
   1.634 +	char *tok[] = {0, 0, 0, 0};
   1.635 +	face->elem = 0;
   1.636 +
   1.637 +	for(int i=0; i<4; i++) {
   1.638 +		if((!(tok[i] = strtok(0, SEP)) || !is_int(tok[i]))) {
   1.639 +			if(i < 3) return false;	// less than 3 verts? not a polygon
   1.640 +		} else {
   1.641 +			face->elem++;
   1.642 +		}
   1.643 +	}
   1.644 +
   1.645 +	for(int i=0; i<4; i++) {
   1.646 +		char *subtok = tok[i];
   1.647 +
   1.648 +		if(!subtok || !*subtok || !is_int(subtok)) {
   1.649 +			if(i < 3) {
   1.650 +				return false;
   1.651 +			}
   1.652 +			face->v[i] = INVALID_IDX;
   1.653 +		} else {
   1.654 +			face->v[i] = atoi(subtok);
   1.655 +			if(face->v[i] > 0) face->v[i]--;	/* convert to 0-based */
   1.656 +		}
   1.657 +
   1.658 +		while(subtok && *subtok && *subtok != '/') {
   1.659 +			subtok++;
   1.660 +		}
   1.661 +		if(subtok && *subtok && *++subtok && is_int(subtok)) {
   1.662 +			face->t[i] = atoi(subtok);
   1.663 +			if(face->t[i] > 0) face->t[i]--;	/* convert to 0-based */
   1.664 +		} else {
   1.665 +			face->t[i] = INVALID_IDX;
   1.666 +		}
   1.667 +
   1.668 +		while(subtok && *subtok && *subtok != '/') {
   1.669 +			subtok++;
   1.670 +		}
   1.671 +		if(subtok && *subtok && *++subtok && is_int(subtok)) {
   1.672 +			face->n[i] = atoi(subtok);
   1.673 +			if(face->n[i] > 0) face->n[i]--;	/* convert to 0-based */
   1.674 +		} else {
   1.675 +			face->n[i] = INVALID_IDX;
   1.676 +		}
   1.677 +	}
   1.678 +
   1.679 +	return true;
   1.680 +}
   1.681 +
   1.682 +static const char *parse_map()
   1.683 +{
   1.684 +	char *tok, *prev = 0;
   1.685 +
   1.686 +	while((tok = strtok(0, SEP))) {
   1.687 +		prev = tok;
   1.688 +	}
   1.689 +
   1.690 +	return prev ? prev : "";
   1.691 +}
   1.692 +
   1.693 +static bool find_file(char *res, int sz, const char *fname, const char *path, const char *mode)
   1.694 +{
   1.695 +	FILE *fp;
   1.696 +	const char *beg, *end;
   1.697 +	int fnamelen = strlen(fname);
   1.698 +
   1.699 +	beg = path;
   1.700 +	while(beg && *beg) {
   1.701 +		end = beg;
   1.702 +		while(*end && *end != ':') {
   1.703 +			end++;
   1.704 +		}
   1.705 +
   1.706 +		int res_len = end - beg;
   1.707 +		char *pathname = (char*)alloca(res_len + fnamelen + 2);
   1.708 +		memcpy(pathname, beg, res_len);
   1.709 +		pathname[res_len] = 0;
   1.710 +		if(res_len) {
   1.711 +			strcat(pathname, "/");
   1.712 +		}
   1.713 +		strcat(pathname, fname);
   1.714 +
   1.715 +		if((fp = fopen(pathname, mode))) {
   1.716 +			fclose(fp);
   1.717 +			strncpy(res, pathname, sz);
   1.718 +			return true;
   1.719 +		}
   1.720 +
   1.721 +		beg += res_len;
   1.722 +		if(*beg == ':') beg++;
   1.723 +	}
   1.724 +	return false;
   1.725 +}
   1.726 +
   1.727 +static const char *dirname(const char *str)
   1.728 +{
   1.729 +	static char buf[PATH_MAX];
   1.730 +
   1.731 +	if(!str || !*str) {
   1.732 +		strcpy(buf, ".");
   1.733 +	} else {
   1.734 +		strncpy(buf, str, PATH_MAX);
   1.735 +		char *ptr = strrchr(buf, '/');
   1.736 +
   1.737 +		if(ptr && *ptr) {
   1.738 +			*ptr = 0;
   1.739 +		} else {
   1.740 +			strcpy(buf, ".");
   1.741 +		}
   1.742 +	}
   1.743 +	return buf;
   1.744 +}
   1.745 +
   1.746 +static Vector3 operator -(const Vector3 &a, const Vector3 &b)
   1.747 +{
   1.748 +	return Vector3(a.x - b.x, a.y - b.y, a.z - b.z);
   1.749 +}
   1.750 +
   1.751 +static Vector3 cross(const Vector3 &a, const Vector3 &b)
   1.752 +{
   1.753 +	Vector3 res;
   1.754 +	res.x = a.y * b.z - a.z * b.y;
   1.755 +	res.y = a.z * b.x - a.x * b.z;
   1.756 +	res.z = a.x * b.y - a.y * b.x;
   1.757 +	return res;
   1.758 +}