X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=dosdemo;a=blobdiff_plain;f=src%2F3dgfx%2Fmeshload.c;fp=src%2F3dgfx%2Fmeshload.c;h=d6e42a4f5d1ace7561227b930901e89384379875;hp=0000000000000000000000000000000000000000;hb=57bd2dc519c47f434e3e5acf998fb9c72448cbce;hpb=d956a9d9273eebfacfda58cb3bafff017269d5dc

diff --git a/src/3dgfx/meshload.c b/src/3dgfx/meshload.c
new file mode 100644
index 0000000..d6e42a4
--- /dev/null
+++ b/src/3dgfx/meshload.c
@@ -0,0 +1,355 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <assert.h>
+#include "mesh.h"
+#include "dynarr.h"
+#include "rbtree.h"
+#include "3dgfx.h"
+#include "util.h"
+
+typedef struct { float x, y; } vec2_t;
+typedef struct { float x, y, z; } vec3_t;
+typedef struct { float x, y, z, w; } vec4_t;
+
+
+struct vertex_pos_color {
+	float x, y, z;
+	float r, g, b, a;
+};
+
+struct facevertex {
+	int vidx, tidx, nidx;
+};
+
+static char *clean_line(char *s);
+static char *parse_face_vert(char *ptr, struct facevertex *fv, int numv, int numt, int numn);
+static int cmp_facevert(const void *ap, const void *bp);
+static void free_rbnode_key(struct rbnode *n, void *cls);
+
+/* merge of different indices per attribute happens during face processing.
+ *
+ * A triplet of (vertex index/texcoord index/normal index) is used as the key
+ * to search in a balanced binary search tree for vertex buffer index assigned
+ * to the same triplet if it has been encountered before. That index is
+ * appended to the index buffer.
+ *
+ * If a particular triplet has not been encountered before, a new g3d_vertex is
+ * appended to the vertex buffer. The index of this new vertex is appended to
+ * the index buffer, and also inserted into the tree for future searches.
+ */
+int load_mesh(struct g3d_mesh *mesh, const char *fname)
+{
+	int i, line_num = 0, result = -1;
+	int found_quad = 0;
+	FILE *fp = 0;
+	char buf[256];
+	struct vertex_pos_color *varr = 0;
+	vec3_t *narr = 0;
+	vec2_t *tarr = 0;
+	struct rbtree *rbtree = 0;
+
+	if(!(fp = fopen(fname, "rb"))) {
+		fprintf(stderr, "load_mesh: failed to open file: %s\n", fname);
+		goto err;
+	}
+
+	if(!(rbtree = rb_create(cmp_facevert))) {
+		fprintf(stderr, "load_mesh: failed to create facevertex binary search tree\n");
+		goto err;
+	}
+	rb_set_delete_func(rbtree, free_rbnode_key, 0);
+
+	if(!(mesh->varr = dynarr_alloc(0, sizeof *mesh->varr)) ||
+			!(mesh->iarr = dynarr_alloc(0, sizeof *mesh->iarr))) {
+		fprintf(stderr, "load_mesh: failed to allocate resizable mesh arrays\n");
+		goto err;
+	}
+	if(!(varr = dynarr_alloc(0, sizeof *varr)) ||
+			!(narr = dynarr_alloc(0, sizeof *narr)) ||
+			!(tarr = dynarr_alloc(0, sizeof *tarr))) {
+		fprintf(stderr, "load_mesh: failed to allocate resizable vertex array\n");
+		goto err;
+	}
+
+	while(fgets(buf, sizeof buf, fp)) {
+		char *line = clean_line(buf);
+		++line_num;
+
+		if(!*line) continue;
+
+		switch(line[0]) {
+		case 'v':
+			if(isspace(line[1])) {
+				/* vertex */
+				struct vertex_pos_color v;
+				int num;
+
+				num = sscanf(line + 2, "%f %f %f %f %f %f %f", &v.x, &v.y, &v.z, &v.r, &v.g, &v.b, &v.a);
+				if(num < 3) {
+					fprintf(stderr, "%s:%d: invalid vertex definition: \"%s\"\n", fname, line_num, line);
+					goto err;
+				}
+				switch(num) {
+				case 3:
+					v.r = 1.0f;
+				case 4:
+					v.g = 1.0f;
+				case 5:
+					v.b = 1.0f;
+				case 6:
+					v.a = 1.0f;
+				}
+				if(!(varr = dynarr_push(varr, &v))) {
+					fprintf(stderr, "load_mesh: failed to resize vertex buffer\n");
+					goto err;
+				}
+
+			} else if(line[1] == 't' && isspace(line[2])) {
+				/* texcoord */
+				vec2_t tc;
+				if(sscanf(line + 3, "%f %f", &tc.x, &tc.y) != 2) {
+					fprintf(stderr, "%s:%d: invalid texcoord definition: \"%s\"\n", fname, line_num, line);
+					goto err;
+				}
+				tc.y = 1.0f - tc.y;
+				if(!(tarr = dynarr_push(tarr, &tc))) {
+					fprintf(stderr, "load_mesh: failed to resize texcoord buffer\n");
+					goto err;
+				}
+
+			} else if(line[1] == 'n' && isspace(line[2])) {
+				/* normal */
+				vec3_t norm;
+				if(sscanf(line + 3, "%f %f %f", &norm.x, &norm.y, &norm.z) != 3) {
+					fprintf(stderr, "%s:%d: invalid normal definition: \"%s\"\n", fname, line_num, line);
+					goto err;
+				}
+				if(!(narr = dynarr_push(narr, &norm))) {
+					fprintf(stderr, "load_mesh: failed to resize normal buffer\n");
+					goto err;
+				}
+			}
+			break;
+
+		case 'f':
+			if(isspace(line[1])) {
+				/* face */
+				char *ptr = line + 2;
+				struct facevertex fv;
+				struct rbnode *node;
+				int vsz = dynarr_size(varr);
+				int tsz = dynarr_size(tarr);
+				int nsz = dynarr_size(narr);
+
+				for(i=0; i<4; i++) {
+					if(!(ptr = parse_face_vert(ptr, &fv, vsz, tsz, nsz))) {
+						if(i < 3 || found_quad) {
+							fprintf(stderr, "%s:%d: invalid face definition: \"%s\"\n", fname, line_num, line);
+							goto err;
+						} else {
+							break;
+						}
+					}
+
+					if((node = rb_find(rbtree, &fv))) {
+						uint16_t idx = (int)(intptr_t)node->data;
+						if(!(mesh->iarr = dynarr_push(mesh->iarr, &idx))) {
+							fprintf(stderr, "load_mesh: failed to resize index array\n");
+							goto err;
+						}
+					} else {
+						uint16_t newidx = dynarr_size(mesh->varr);
+						struct g3d_vertex v;
+						struct facevertex *newfv;
+
+						v.x = varr[fv.vidx].x;
+						v.y = varr[fv.vidx].y;
+						v.z = varr[fv.vidx].z;
+						v.w = 1.0f;
+						v.r = cround64(varr[fv.vidx].r * 255.0);
+						v.g = cround64(varr[fv.vidx].g * 255.0);
+						v.b = cround64(varr[fv.vidx].b * 255.0);
+						v.a = cround64(varr[fv.vidx].a * 255.0);
+						if(fv.tidx >= 0) {
+							v.u = tarr[fv.tidx].x;
+							v.v = tarr[fv.tidx].y;
+						} else {
+							v.u = v.x;
+							v.v = v.y;
+						}
+						if(fv.nidx >= 0) {
+							v.nx = narr[fv.nidx].x;
+							v.ny = narr[fv.nidx].y;
+							v.nz = narr[fv.nidx].z;
+						} else {
+							v.nx = v.ny = 0.0f;
+							v.nz = 1.0f;
+						}
+
+						if(!(mesh->varr = dynarr_push(mesh->varr, &v))) {
+							fprintf(stderr, "load_mesh: failed to resize combined vertex array\n");
+							goto err;
+						}
+						if(!(mesh->iarr = dynarr_push(mesh->iarr, &newidx))) {
+							fprintf(stderr, "load_mesh: failed to resize index array\n");
+							goto err;
+						}
+
+						if((newfv = malloc(sizeof *newfv))) {
+							*newfv = fv;
+						}
+						if(!newfv || rb_insert(rbtree, newfv, (void*)(intptr_t)newidx) == -1) {
+							fprintf(stderr, "load_mesh: failed to insert facevertex to the binary search tree\n");
+							goto err;
+						}
+					}
+				}
+				if(i > 3) found_quad = 1;
+			}
+			break;
+
+		default:
+			break;
+		}
+	}
+
+	mesh->prim = found_quad ? G3D_QUADS : G3D_TRIANGLES;
+	mesh->vcount = dynarr_size(mesh->varr);
+	mesh->icount = dynarr_size(mesh->iarr);
+	mesh->varr = dynarr_finalize(mesh->varr);
+	mesh->iarr = dynarr_finalize(mesh->iarr);
+	result = 0;	/* success */
+
+	printf("loaded %s mesh: %s: %d vertices, %d faces\n", found_quad ? "quad" : "triangle",
+			fname, mesh->vcount, mesh->icount / mesh->prim);
+
+err:
+	if(fp) fclose(fp);
+	dynarr_free(varr);
+	dynarr_free(narr);
+	dynarr_free(tarr);
+	if(result == -1) {
+		dynarr_free(mesh->varr);
+		dynarr_free(mesh->iarr);
+	}
+	rb_free(rbtree);
+	return result;
+}
+
+int save_mesh(struct g3d_mesh *mesh, const char *fname)
+{
+	int i, fvcount;
+	FILE *fp;
+
+	if(!(fp = fopen(fname, "wb"))) {
+		fprintf(stderr, "save_mesh: failed to open %s for writing\n", fname);
+		return -1;
+	}
+	fprintf(fp, "# Wavefront OBJ file shoved in your FACE by Mindlapse. Deal with it\n");
+
+	for(i=0; i<mesh->vcount; i++) {
+		struct g3d_vertex *v = mesh->varr + i;
+		fprintf(fp, "v %f %f %f %f %f %f %f\n", v->x, v->y, v->z, v->r / 255.0f, v->g / 255.0f,
+				v->b / 255.0f, v->a / 255.0f);
+	}
+	for(i=0; i<mesh->vcount; i++) {
+		fprintf(fp, "vn %f %f %f\n", mesh->varr[i].nx, mesh->varr[i].ny, mesh->varr[i].nz);
+	}
+	for(i=0; i<mesh->vcount; i++) {
+		fprintf(fp, "vt %f %f\n", mesh->varr[i].u, mesh->varr[i].v);
+	}
+
+	fvcount = mesh->prim;
+	for(i=0; i<mesh->icount; i++) {
+		int idx = mesh->iarr[i] + 1;
+
+		if(fvcount == mesh->prim) {
+			fprintf(fp, "\nf");
+			fvcount = 0;
+		}
+		fprintf(fp, " %d/%d/%d", idx, idx, idx);
+		++fvcount;
+	}
+	fprintf(fp, "\n");
+
+	fclose(fp);
+	return 0;
+}
+
+static char *clean_line(char *s)
+{
+	char *end;
+
+	while(*s && isspace(*s)) ++s;
+	if(!*s) return 0;
+
+	end = s;
+	while(*end && *end != '#') ++end;
+	*end = 0;
+
+	while(end > s && isspace(*end)) --end;
+	*end = 0;
+
+	return s;
+}
+
+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)
+{
+	if(!(ptr = parse_idx(ptr, &fv->vidx, numv)))
+		return 0;
+	if(*ptr != '/') return (!*ptr || isspace(*ptr)) ? ptr : 0;
+
+	if(*++ptr == '/') {	/* no texcoord */
+		fv->tidx = -1;
+		++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 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);
+}