# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1279652561 -3600
# Node ID b06518bb16e95cd6153d307741429adae9b6fa6d
# Parent  9f0ddb7018829343596e0a9d2a8f233d4bd3fb83
adding polygon meshes and obj loading

diff -r 9f0ddb701882 -r b06518bb16e9 src/mesh.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mesh.cc	Tue Jul 20 20:02:41 2010 +0100
@@ -0,0 +1,631 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <string>
+#include <vector>
+#include <map>
+#include "mesh.h"
+
+using namespace std;
+
+#define COMMANDS 	\
+	CMD(V),			\
+	CMD(VN),		\
+	CMD(VT),		\
+	CMD(F),			\
+	CMD(O),			\
+	CMD(G),			\
+	CMD(MTLLIB),	\
+	CMD(USEMTL),	\
+	CMD(NEWMTL),	\
+	CMD(KA),		\
+	CMD(KD),		\
+	CMD(KS),		\
+	CMD(NS),		\
+	CMD(NI),		\
+	CMD(D),			\
+	CMD(TR),		\
+	CMD(MAP_KD),	\
+	CMD(MAP_KS),	\
+	CMD(MAP_NS),	\
+	CMD(MAP_D),		\
+	CMD(REFL),		\
+	CMD(BUMP)
+
+#define CMD(x)	CMD_##x
+enum {
+	COMMANDS,
+	CMD_UNK
+};
+#undef CMD
+
+#define CMD(x)	#x
+static const char *cmd_names[] = {
+	COMMANDS,
+	0
+};
+#undef CMD
+
+struct Vector3 {
+	float x, y, z;
+
+	Vector3() { x = y = z = 0.0; }
+	Vector3(float a, float b, float c) { x = a; y = b; z = c; }
+};
+
+struct Vector2 {
+	float x, y;
+
+	Vector2() { x = y = 0.0; }
+	Vector2(float a, float b) { x = a; y = b; }
+};
+
+struct obj_face {
+	int elem;
+	int v[4], n[4], t[4];
+};
+
+struct obj_file {
+	string cur_obj, cur_mat;
+	vector<Vector3> v, vn, vt;
+	vector<obj_face> f;
+};
+
+struct obj_mat {
+	string name;		// newmtl <name>
+	Vector3 ambient, diffuse, specular;	// Ka, Kd, Ks
+	float shininess;	// Ns
+	float ior;			// Ni
+	float alpha;		// d, Tr
+
+	string tex_dif, tex_spec, tex_shin, tex_alpha;	// map_Kd, map_Ks, map_Ns, map_d
+	string tex_refl;	// refl -type sphere|cube file
+	string tex_bump;	// bump
+
+	obj_mat() { reset(); }
+
+	void reset() {
+		ambient = diffuse = Vector3(0.5, 0.5, 0.5);
+		specular = Vector3(0.0, 0.0, 0.0);
+		name = tex_dif = tex_spec = tex_shin = tex_alpha = tex_refl = tex_bump = "";
+		shininess = 0;
+		ior = alpha = 1;
+	}
+};
+
+static bool read_materials(FILE *fp, vector<obj_mat> *vmtl);
+static Mesh *cons_mesh(obj_file *obj);
+
+static int get_cmd(char *str);
+static bool is_int(const char *str);
+static bool is_float(const char *str);
+static bool parse_vec(Vector3 *vec);
+static bool parse_color(Vector3 *col);
+static bool parse_face(obj_face *face);
+static const char *parse_map();
+
+static bool find_file(char *res, int sz, const char *fname, const char *path = ".", const char *mode = "rb");
+static const char *dirname(const char *str);
+
+static map<string, int> matnames;
+
+
+#define INVALID_IDX		INT_MIN
+
+#define SEP		" \t\n\r\v"
+#define BUF_SZ	512
+
+bool Scene::load(const char *fname)
+{
+	FILE *fp;
+
+	if(!(fp = fopen(fname, "rb"))) {
+		fprintf(stderr, "failed to open %s: %s\n", fname, strerror(errno));
+		return false;
+	}
+
+	bool res = load(fp);
+	fclose(fp);
+	return res;
+}
+
+bool Scene::load(FILE *fp)
+{
+	static int seq;
+	char cur_name[16];
+
+	obj_file obj;
+	
+	sprintf(cur_name, "default%02d.obj", seq++);
+	obj.cur_obj = cur_name;
+
+	int prev_cmd = 0, obj_added = 0;
+	for(;;) {
+		Vector3 vec;
+		obj_face face;
+		
+		char line[BUF_SZ];
+		fgets(line, sizeof line, fp);
+		if(feof(fp)) {
+			break;
+		}
+
+		char *tok;
+		if(!(tok = strtok(line, SEP))) {
+			continue; // ignore empty lines
+		}
+
+		int cmd;
+		if((cmd = get_cmd(tok)) == -1) {
+			continue; // ignore unknown commands ...
+		}
+
+		switch(cmd) {
+		case CMD_V:
+			if(!parse_vec(&vec)) {
+				continue;
+			}
+			obj.v.push_back(vec);
+			break;
+
+		case CMD_VN:
+			if(!parse_vec(&vec)) {
+				continue;
+			}
+			obj.vn.push_back(vec);
+			break;
+
+		case CMD_VT:
+			if(!parse_vec(&vec)) {
+				continue;
+			}
+			vec.y = 1.0 - vec.y;
+			obj.vt.push_back(vec);
+			break;
+
+		case CMD_O:
+		case CMD_G:
+			if(prev_cmd == CMD_O || prev_cmd == CMD_G) {
+				break;	// just in case we've got both of them in a row
+			}
+			/* if we have any previous data, group them up, add the object
+			 * and continue with the new one...
+			 */
+			if(!obj.f.empty()) {
+				Mesh *mesh = cons_mesh(&obj);
+				mesh->matid = matnames[obj.cur_mat];
+				meshes.push_back(mesh);
+				obj_added++;
+
+				obj.f.clear();	// clean the face list
+			}
+			if((tok = strtok(0, SEP))) {
+				obj.cur_obj = tok;
+			} else {
+				sprintf(cur_name, "default%02d.obj", seq++);
+				obj.cur_obj = cur_name;
+			}
+			break;
+
+		case CMD_MTLLIB:
+			if((tok = strtok(0, SEP))) {
+				char path[PATH_MAX];
+
+				sprintf(path, ".:%s", dirname(tok));
+				if(!find_file(path, PATH_MAX, tok, path)) {
+					fprintf(stderr, "material library not found: %s\n", tok);
+					continue;
+				}
+
+				FILE *mfile;
+				if(!(mfile = fopen(path, "rb"))) {
+					fprintf(stderr, "failed to open material library: %s\n", path);
+					continue;
+				}
+
+				// load all materials of the mtl file into a vector
+				vector<obj_mat> vmtl;
+				if(!read_materials(mfile, &vmtl)) {
+					continue;
+				}
+				fclose(mfile);
+
+				// and add them all to the scene
+				for(size_t i=0; i<vmtl.size(); i++) {
+					Material mat;
+
+					mat.kd[0] = vmtl[i].diffuse.x;
+					mat.kd[1] = vmtl[i].diffuse.y;
+					mat.kd[2] = vmtl[i].diffuse.z;
+
+					mat.ks[0] = vmtl[i].specular.x;
+					mat.ks[1] = vmtl[i].specular.y;
+					mat.ks[2] = vmtl[i].specular.z;
+
+					mat.kt = 1.0 - vmtl[i].alpha;
+					mat.kr = 0.0;	// TODO
+					mat.spow = vmtl[i].shininess;
+					
+					matnames[vmtl[i].name] = i;
+				}
+			}
+			break;
+
+		case CMD_USEMTL:
+			if((tok = strtok(0, SEP))) {
+				obj.cur_mat = tok;
+			} else {
+				obj.cur_mat = "";
+			}
+			break;
+
+		case CMD_F:
+			if(!parse_face(&face)) {
+				continue;
+			}
+
+			// convert negative indices to regular indices
+			for(int i=0; i<4; i++) {
+				if(face.v[i] < 0 && face.v[i] != INVALID_IDX) {
+					face.v[i] = obj.v.size() + face.v[i];
+				}
+				if(face.n[i] < 0 && face.n[i] != INVALID_IDX) {
+					face.n[i] = obj.vn.size() + face.n[i];
+				}
+				if(face.t[i] < 0 && face.t[i] != INVALID_IDX) {
+					face.t[i] = obj.vt.size() + face.t[i];
+				}
+			}
+
+			// break quads into triangles if needed
+			obj.f.push_back(face);
+			if(face.elem == 4) {
+				face.v[1] = face.v[2];
+				face.n[1] = face.n[2];
+				face.t[1] = face.t[2];
+
+				face.v[2] = face.v[3];
+				face.n[2] = face.n[3];
+				face.t[2] = face.t[3];
+
+				obj.f.push_back(face);
+			}
+			break;
+
+		default:
+			break;	// ignore unknown commands
+		}
+
+		prev_cmd = cmd;
+	}
+
+	// reached end of file...
+	if(!obj.f.empty()) {
+		Mesh *mesh = cons_mesh(&obj);
+		mesh->matid = matnames[obj.cur_mat];
+		meshes.push_back(mesh);
+		obj_added++;
+	}
+
+	return obj_added > 0;
+}
+
+static Mesh *cons_mesh(obj_file *obj)
+{
+	Mesh *mesh;
+
+	// need at least one of each element
+	bool added_norm = false, added_tc = false;
+	if(obj->vn.empty()) {
+		obj->vn.push_back(Vector3(0, 0, 0));
+		added_norm = true;
+	}
+	if(obj->vt.empty()) {
+		obj->vt.push_back(Vector3(0, 0, 0));
+		added_tc = true;
+	}
+
+	mesh = new Mesh;
+
+	for(size_t i=0; i<obj->f.size(); i++) {
+		Face face;
+
+		for(int j=0; j<3; j++) {
+			obj_face *f = &obj->f[i];
+
+			face.v[j].pos[0] = obj->v[f->v[j]].x;
+			face.v[j].pos[1] = obj->v[f->v[j]].y;
+			face.v[j].pos[2] = obj->v[f->v[j]].z;
+
+			int nidx = f->n[j] < 0 ? 0 : f->n[j];
+			face.v[j].normal[0] = obj->vn[nidx].x;
+			face.v[j].normal[1] = obj->vn[nidx].y;
+			face.v[j].normal[2] = obj->vn[nidx].z;
+
+			int tidx = f->t[j] < 0 ? 0 : f->t[j];
+			face.v[j].tex[0] = obj->vt[tidx].x;
+			face.v[j].tex[1] = obj->vt[tidx].y;
+		}
+		mesh->faces.push_back(face);
+	}
+
+	if(added_norm) {
+		obj->vn.pop_back();
+	}
+	if(added_tc) {
+		obj->vt.pop_back();
+	}
+	
+	return mesh;
+}
+
+static bool read_materials(FILE *fp, vector<obj_mat> *vmtl)
+{
+	obj_mat mat;
+
+	for(;;) {
+		char line[BUF_SZ];
+		fgets(line, sizeof line, fp);
+		if(feof(fp)) {
+			break;
+		}
+
+		char *tok;
+		if(!(tok = strtok(line, SEP))) {
+			continue;
+		}
+
+		int cmd;
+		if((cmd = get_cmd(tok)) == -1) {
+			continue;
+		}
+
+		switch(cmd) {
+		case CMD_NEWMTL:
+			// add the previous material, and start a new one
+			if(mat.name.length() > 0) {
+				vmtl->push_back(mat);
+				mat.reset();
+			}
+			if((tok = strtok(0, SEP))) {
+				mat.name = tok;
+			}
+			break;
+
+		case CMD_KA:
+			parse_color(&mat.ambient);
+			break;
+
+		case CMD_KD:
+			parse_color(&mat.diffuse);
+			break;
+
+		case CMD_KS:
+			parse_color(&mat.specular);
+			break;
+
+		case CMD_NS:
+			if((tok = strtok(0, SEP)) && is_float(tok)) {
+				mat.shininess = atof(tok);
+			}
+			break;
+
+		case CMD_NI:
+			if((tok = strtok(0, SEP)) && is_float(tok)) {
+				mat.ior = atof(tok);
+			}
+			break;
+
+		case CMD_D:
+		case CMD_TR:
+			{
+				Vector3 c;
+				if(parse_color(&c)) {
+					mat.alpha = cmd == CMD_D ? c.x : 1.0 - c.x;
+				}
+			}
+			break;
+
+		case CMD_MAP_KD:
+			mat.tex_dif = parse_map();
+			break;
+
+		default:
+			break;
+		}
+	}
+
+	if(mat.name.length() > 0) {
+		vmtl->push_back(mat);
+	}
+	return true;
+}
+
+static int get_cmd(char *str)
+{
+	char *s = str;
+	while((*s = toupper(*s))) s++; 
+
+	for(int i=0; cmd_names[i]; i++) {
+		if(strcmp(str, cmd_names[i]) == 0) {
+			return i;
+		}
+	}
+	return CMD_UNK;
+}
+
+static bool is_int(const char *str)
+{
+	char *tmp;
+	strtol(str, &tmp, 10);
+	return tmp != str;
+}
+
+static bool is_float(const char *str)
+{
+	char *tmp;
+	strtod(str, &tmp);
+	return tmp != str;
+}
+
+static bool parse_vec(Vector3 *vec)
+{
+	for(int i=0; i<3; i++) {
+		char *tok;
+
+		if(!(tok = strtok(0, SEP)) || !is_float(tok)) {
+			if(i < 2) {
+				return false;
+			}
+			vec->z = 0.0;
+		} else {
+			float v = atof(tok);
+
+			switch(i) {
+			case 0:
+				vec->x = v;
+				break;
+			case 1:
+				vec->y = v;
+				break;
+			case 2:
+				vec->z = v;
+				break;
+			}
+		}
+	}
+	return true;
+}
+
+static bool parse_color(Vector3 *col)
+{
+	for(int i=0; i<3; i++) {
+		char *tok;
+
+		if(!(tok = strtok(0, SEP)) || !is_float(tok)) {
+			col->y = col->z = col->x;
+			return i > 0 ? true : false;
+		}
+
+		float v = atof(tok);
+		switch(i) {
+		case 0:
+			col->x = v;
+			break;
+		case 1:
+			col->y = v;
+			break;
+		case 2:
+			col->z = v;
+			break;
+		}
+	}
+	return true;
+}
+
+static bool parse_face(obj_face *face)
+{
+	char *tok[] = {0, 0, 0, 0};
+	face->elem = 0;
+
+	for(int i=0; i<4; i++) {
+		if((!(tok[i] = strtok(0, SEP)) || !is_int(tok[i]))) {
+			if(i < 3) return false;	// less than 3 verts? not a polygon
+		} else {
+			face->elem++;
+		}
+	}
+
+	for(int i=0; i<4; i++) {
+		char *subtok = tok[i];
+
+		if(!subtok || !*subtok || !is_int(subtok)) {
+			if(i < 3) {
+				return false;
+			}
+			face->v[i] = INVALID_IDX;
+		} else {
+			face->v[i] = atoi(subtok);
+			if(face->v[i] > 0) face->v[i]--;	/* convert to 0-based */
+		}
+
+		while(subtok && *subtok && *subtok != '/') {
+			subtok++;
+		}
+		if(subtok && *subtok && *++subtok && is_int(subtok)) {
+			face->t[i] = atoi(subtok);
+			if(face->t[i] > 0) face->t[i]--;	/* convert to 0-based */
+		} else {
+			face->t[i] = INVALID_IDX;
+		}
+
+		while(subtok && *subtok && *subtok != '/') {
+			subtok++;
+		}
+		if(subtok && *subtok && *++subtok && is_int(subtok)) {
+			face->n[i] = atoi(subtok);
+			if(face->n[i] > 0) face->n[i]--;	/* convert to 0-based */
+		} else {
+			face->n[i] = INVALID_IDX;
+		}
+	}
+
+	return true;
+}
+
+static const char *parse_map()
+{
+	char *tok, *prev = 0;
+
+	while((tok = strtok(0, SEP))) {
+		prev = tok;
+	}
+
+	return prev ? prev : "";
+}
+
+static bool find_file(char *res, int sz, const char *fname, const char *path, const char *mode)
+{
+	FILE *fp;
+	const char *beg, *end;
+	int fnamelen = strlen(fname);
+
+	beg = path;
+	while(beg && *beg) {
+		end = beg;
+		while(*end && *end != ':') {
+			end++;
+		}
+
+		int sz = end - beg + 1;
+		char *pathname = (char*)alloca(sz + fnamelen + 2);
+		memcpy(pathname, beg, sz);
+		strcat(pathname, "/");
+		strcat(pathname, fname);
+
+		if((fp = fopen(pathname, mode))) {
+			fclose(fp);
+			strncpy(res, pathname, sz);
+			return true;
+		}
+
+		beg += sz;
+	}
+	return false;
+}
+
+static const char *dirname(const char *str)
+{
+	static char buf[PATH_MAX];
+
+	if(!str || !*str) {
+		strcpy(buf, ".");
+	} else {
+		strncpy(buf, str, PATH_MAX);
+		char *ptr = strrchr(buf, '/');
+
+		if(*ptr) *ptr = 0;
+	}
+	return buf;
+}
diff -r 9f0ddb701882 -r b06518bb16e9 src/mesh.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mesh.h	Tue Jul 20 20:02:41 2010 +0100
@@ -0,0 +1,38 @@
+#ifndef MESH_H_
+#define MESH_H_
+
+#include <vector>
+
+struct Vertex {
+	float pos[3];
+	float normal[3];
+	float tex[2];
+};
+
+struct Face {
+	Vertex v[3];
+	float normal[3];
+	int matid;
+};
+
+struct Material {
+	float kd[3], ks[3];
+	float kr, kt;
+	float spow;
+};
+
+struct Mesh {
+	std::vector<Face> faces;
+	int matid;
+};
+
+class Scene {
+public:
+	std::vector<Mesh*> meshes;
+	std::vector<Material> matlib;
+
+	bool load(const char *fname);
+	bool load(FILE *fp);
+};
+
+#endif	/* MESH_H_ */