+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <assert.h>
+#include "cgmath/cgmath.h"
+#include "scenefile.h"
+#include "rbtree.h"
+
+struct facevertex {
+ int vidx, tidx, nidx;
+};
+
+struct objmtl {
+ char *name;
+ cgm_vec3 ka, kd, ks, ke;
+ float shin;
+ float alpha;
+ float ior;
+ char *map_kd, *map_ke, *map_alpha;
+ struct objmtl *next;
+};
+
+static int proc_facevert(struct mesh *mesh, struct facevertex *fv,
+ cgm_vec3 *varr, cgm_vec3 *narr, cgm_vec2 *tarr, struct rbtree *rbtree);
+
+static char *cleanline(char *s);
+static char *parse_idx(char *ptr, int *idx, int arrsz);
+static char *parse_face_vert(char *ptr, struct facevertex *fv, int numv, int numt, int numn);
+
+static int load_mtllib(struct scenefile *scn, const char *path_prefix, const char *mtlfname);
+static void free_mtllist(struct material *mtl);
+static void conv_mtl(struct material *mm, struct objmtl *om, const char *path_prefix);
+
+static int cmp_facevert(const void *ap, const void *bp);
+static void free_rbnode_key(struct rbnode *n, void *cls);
+
+#define GROW_ARRAY(arr, sz) \
+ do { \
+ int newsz = (sz) ? (sz) * 2 : 16; \
+ void *tmp = realloc(arr, newsz * sizeof *(arr)); \
+ if(!tmp) { \
+ fprintf(stderr, "failed to grow array to %d\n", newsz); \
+ goto fail; \
+ } \
+ arr = tmp; \
+ sz = newsz; \
+ } while(0)
+
+
+int load_scenefile(struct scenefile *scn, const char *fname)
+{
+ int i, nlines, res = -1;
+ FILE *fp;
+ char buf[256], *line, *ptr, *path_prefix;
+ int varr_size, varr_max, narr_size, narr_max, tarr_size, tarr_max;
+ cgm_vec3 v, *varr = 0, *narr = 0;
+ cgm_vec2 *tarr = 0;
+ struct facevertex fv[4];
+ struct mesh *mesh;
+ struct material *mtl = 0;
+ char *sep;
+ struct rbtree *rbtree = 0;
+
+
+ varr_size = varr_max = narr_size = narr_max = tarr_size = tarr_max = 0;
+ varr = narr = 0;
+ tarr = 0;
+
+ if(!(fp = fopen(fname, "rb"))) {
+ fprintf(stderr, "load_scenefile: failed to open %s\n", fname);
+ return -1;
+ }
+
+ if(!(rbtree = rb_create(cmp_facevert))) {
+ fprintf(stderr, "load_scenefile: failed to create facevertex search tree\n");
+ fclose(fp);
+ return -1;
+ }
+ rb_set_delete_func(rbtree, free_rbnode_key, 0);
+
+ strcpy(buf, fname);
+ if((sep = strrchr(buf, '/'))) {
+ sep[1] = 0;
+ } else {
+ buf[0] = 0;
+ }
+ path_prefix = alloca(strlen(buf) + 1);
+ strcpy(path_prefix, buf);
+
+ if(!(mesh = malloc(sizeof *mesh))) {
+ fprintf(stderr, "failed to allocate mesh\n");
+ fclose(fp);
+ return -1;
+ }
+ init_mesh(mesh);
+
+ scn->meshlist = 0;
+ scn->num_meshes = 0;
+
+ nlines = 0;
+ while(fgets(buf, sizeof buf, fp)) {
+ nlines++;
+ if(!(line = cleanline(buf))) {
+ continue;
+ }
+
+ switch(line[0]) {
+ case 'v':
+ v.x = v.y = v.z = 0.0f;
+ if(sscanf(line + 2, "%f %f %f", &v.x, &v.y, &v.z) < 2) {
+ break;
+ }
+ if(isspace(line[1])) {
+ if(varr_size >= varr_max) {
+ GROW_ARRAY(varr, varr_max);
+ }
+ varr[varr_size++] = v;
+ } else if(line[1] == 't' && isspace(line[2])) {
+ if(tarr_size >= tarr_max) {
+ GROW_ARRAY(tarr, tarr_max);
+ }
+ tarr[tarr_size++] = *(cgm_vec2*)&v;
+ } else if(line[1] == 'n' && isspace(line[2])) {
+ if(narr_size >= narr_max) {
+ GROW_ARRAY(narr, narr_max);
+ }
+ narr[narr_size++] = v;
+ }
+ break;
+
+ case 'f':
+ if(!isspace(line[1])) break;
+
+ ptr = line + 2;
+
+ for(i=0; i<3; i++) {
+ if(!(ptr = parse_face_vert(ptr, fv + i, varr_size, tarr_size, narr_size))) {
+ break;
+ }
+ if(proc_facevert(mesh, fv + i, varr, narr, tarr, rbtree) == -1) {
+ break;
+ }
+ }
+
+ if(parse_face_vert(ptr, fv + 3, varr_size, tarr_size, narr_size)) {
+ proc_facevert(mesh, fv, varr, narr, tarr, rbtree);
+ proc_facevert(mesh, fv + 2, varr, narr, tarr, rbtree);
+ proc_facevert(mesh, fv + 3, varr, narr, tarr, rbtree);
+ }
+ break;
+
+ case 'o':
+ case 'g':
+ if(mesh->num_verts) {
+ mesh->mtl = mtl;
+ mesh->next = scn->meshlist;
+ scn->meshlist = mesh;
+ scn->num_meshes++;
+
+ if(!(mesh = malloc(sizeof *mesh))) {
+ fprintf(stderr, "failed to allocate mesh\n");
+ goto fail;
+ }
+ init_mesh(mesh);
+ }
+ break;
+
+ case 'm':
+ if(memcmp(line, "mtllib", 6) == 0 && (line = cleanline(line + 6))) {
+ free_mtllist(scn->mtllist);
+ load_mtllib(scn, path_prefix, line);
+ }
+ break;
+
+ case 'u':
+ if(memcmp(line, "usemtl", 6) == 0 && (line = cleanline(line + 6))) {
+ mtl = scn->mtllist;
+ while(mtl) {
+ if(strcmp(mtl->name, line) == 0) {
+ break;
+ }
+ mtl = mtl->next;
+ }
+ }
+ break;
+
+ default:
+ break;
+ }
+ }
+
+ if(mesh->num_verts) {
+ mesh->mtl = mtl;
+ mesh->next = scn->meshlist;
+ scn->meshlist = mesh;
+ scn->num_meshes++;
+ } else {
+ free(mesh);
+ }
+ mesh = 0;
+
+ printf("load_scenefile: loaded %d meshes, %d vertices\n", scn->num_meshes,
+ varr_size);
+
+ res = 0;
+
+fail:
+ fclose(fp);
+ free(mesh);
+ free(varr);
+ free(narr);
+ free(tarr);
+ rb_free(rbtree);
+ return res;
+}
+
+static int proc_facevert(struct mesh *mesh, struct facevertex *fv,
+ cgm_vec3 *varr, cgm_vec3 *narr, cgm_vec2 *tarr, struct rbtree *rbtree)
+{
+ struct rbnode *node;
+ unsigned int idx, newidx;
+ struct facevertex *newfv;
+ struct vertex v;
+
+ if((node = rb_find(rbtree, &fv))) {
+ idx = (unsigned int)node->data;
+ assert(idx < mesh->num_verts);
+ } else {
+ newidx = mesh->num_verts;
+
+ v.pos = varr[fv->vidx];
+ if(fv->nidx >= 0) {
+ v.norm = narr[fv->nidx];
+ }
+ if(fv->tidx >= 0) {
+ v.tex = tarr[fv->tidx];
+ }
+ add_mesh_vertex(mesh, &v);
+ add_mesh_index(mesh, newidx);
+ }
+
+ if((newfv = malloc(sizeof *newfv))) {
+ *newfv = *fv;
+ }
+ if(!newfv || rb_insert(rbtree, newfv, (void*)newidx) == -1) {
+ fprintf(stderr, "load_scenefile: failed to insert facevertex to rbtree\n");
+ free(newfv);
+ return -1;
+ }
+ return 0;
+}
+
+void destroy_scenefile(struct scenefile *scn)
+{
+ struct mesh *m;
+ while(scn->meshlist) {
+ m = scn->meshlist;
+ scn->meshlist = scn->meshlist->next;
+ free(m);
+ }
+}
+
+static char *cleanline(char *s)
+{
+ char *ptr;
+
+ if((ptr = strchr(s, '#'))) *ptr = 0;
+
+ while(*s && isspace(*s)) s++;
+ ptr = s + strlen(s) - 1;
+ while(ptr >= s && isspace(*ptr)) *ptr-- = 0;
+
+ return *s ? s : 0;
+}
+
+static char *parse_idx(char *ptr, int *idx, int arrsz)
+{
+ char *endp;
+ int val = strtol(ptr, &endp, 10);
+ if(endp == ptr) return 0;
+
+ if(val < 0) { /* convert negative indices */
+ *idx = arrsz + val;
+ } else {
+ *idx = val - 1; /* indices in obj are 1-based */
+ }
+ return endp;
+}
+
+/* possible face-vertex definitions:
+ * 1. vertex
+ * 2. vertex/texcoord
+ * 3. vertex//normal
+ * 4. vertex/texcoord/normal
+ */
+static char *parse_face_vert(char *ptr, struct facevertex *fv, int numv, int numt, int numn)
+{
+ fv->tidx = fv->nidx = -1;
+
+ if(!(ptr = parse_idx(ptr, &fv->vidx, numv)))
+ return 0;
+ if(*ptr != '/') return (!*ptr || isspace(*ptr)) ? ptr : 0;
+
+ if(*++ptr == '/') { /* no texcoord */
+ ++ptr;
+ } else {
+ if(!(ptr = parse_idx(ptr, &fv->tidx, numt)))
+ return 0;
+ if(*ptr != '/') return (!*ptr || isspace(*ptr)) ? ptr : 0;
+ ++ptr;
+ }
+
+ if(!(ptr = parse_idx(ptr, &fv->nidx, numn)))
+ return 0;
+ return (!*ptr || isspace(*ptr)) ? ptr : 0;
+}
+
+static int load_mtllib(struct scenefile *scn, const char *path_prefix, const char *mtlfname)
+{
+ FILE *fp;
+ char buf[256], *line;
+ struct objmtl om;
+ struct material *mtl;
+
+ if(path_prefix && *path_prefix) {
+ sprintf(buf, "%s/%s", path_prefix, mtlfname);
+ } else {
+ strcpy(buf, mtlfname);
+ }
+
+ if(!(fp = fopen(buf, "rb"))) {
+ return -1;
+ }
+
+ while(fgets(buf, sizeof buf, fp)) {
+ if(!(line = cleanline(buf))) {
+ continue;
+ }
+
+ if(memcmp(line, "newmtl", 6) == 0) {
+ if(mtl) {
+ mtl->next = scn->mtllist;
+ scn->mtllist = mtl;
+ }
+ if((mtl = calloc(1, sizeof *mtl))) {
+ if((line = cleanline(line + 6))) {
+ mtl->name = strdup(line);
+ }
+ }
+ } else if(memcmp(line, "Kd", 2) == 0) {
+ sscanf(line + 3, "%f %f %f", &om.kd.x, &om.kd.y, &om.kd.z);
+ } else if(memcmp(line, "Ks", 2) == 0) {
+ sscanf(line + 3, "%f %f %f", &om.ks.x, &om.ks.y, &om.ks.z);
+ } else if(memcmp(line, "Ke", 2) == 0) {
+ sscanf(line + 3, "%f %f %f", &om.ke.x, &om.ke.y, &om.ke.z);
+ } else if(memcmp(line, "Ni", 2) == 0) {
+ om.ior = atof(line + 3);
+ } else if(line[0] == 'd' && isspace(line[1])) {
+ om.alpha = atof(line + 2);
+ } else if(memcmp(line, "map_Kd", 6) == 0) {
+ if((line = cleanline(line + 6))) {
+ om.map_kd = strdup(line);
+ }
+ } else if(memcmp(line, "map_Ke", 6) == 0) {
+ if((line = cleanline(line + 6))) {
+ om.map_ke = strdup(line);
+ }
+ } else if(memcmp(line, "map_d", 5) == 0) {
+ if((line = cleanline(line + 5))) {
+ om.map_alpha = strdup(line);
+ }
+ }
+ conv_mtl(mtl, &om, path_prefix);
+ }
+
+ if(mtl) {
+ mtl->next = scn->mtllist;
+ scn->mtllist = mtl;
+ }
+
+ fclose(fp);
+ return 0;
+}
+
+static void free_mtllist(struct material *mtl)
+{
+ while(mtl) {
+ void *tmp = mtl;
+ mtl = mtl->next;
+ free(tmp);
+ }
+}
+
+static void conv_mtl(struct material *mm, struct objmtl *om, const char *path_prefix)
+{
+ char *fname = 0, *suffix = 0;
+ int len, prefix_len, maxlen = 0;
+
+ memset(mm, 0, sizeof *mm);
+ mm->name = strdup(om->name);
+ mm->color = om->kd;
+ mm->spec = om->ks;
+ mm->shininess = om->shin;
+
+ if(om->map_kd && (len = strlen(om->map_kd)) > maxlen) maxlen = len;
+ if(om->map_ke && (len = strlen(om->map_ke)) > maxlen) maxlen = len;
+ if(om->map_alpha && (len = strlen(om->map_alpha)) > maxlen) maxlen = len;
+
+ if(maxlen) {
+ prefix_len = strlen(path_prefix);
+ fname = alloca(maxlen + prefix_len + 2);
+ suffix = fname + prefix_len;
+ strcpy(fname, path_prefix);
+ }
+
+ /*
+ if(om->map_kd) {
+ strcpy(suffix, om->map_kd);
+ mm->tex[TEX_DIFFUSE] = get_image(fname);
+ }
+ */
+}
+
+static int cmp_facevert(const void *ap, const void *bp)
+{
+ const struct facevertex *a = ap;
+ const struct facevertex *b = bp;
+
+ if(a->vidx == b->vidx) {
+ if(a->tidx == b->tidx) {
+ return a->nidx - b->nidx;
+ }
+ return a->tidx - b->tidx;
+ }
+ return a->vidx - b->vidx;
+}
+
+static void free_rbnode_key(struct rbnode *n, void *cls)
+{
+ free(n->key);
+}