1 files changed, 65 insertions, 0 deletions
diff --git a/obj.c b/obj.c
new file mode 100644
index 0000000..9f2a9d9
--- /dev/null
+++ b/obj.c
@@ -0,0 +1,65 @@
+#include <u.h>
+#include <libc.h>
+#include <ctype.h>
+#include <bio.h>
+#include <draw.h>
+#include "dat.h"
+#include "fns.h"
+
+Vector3 *verts;
+Triangle3 *tris;
+int nvert, ntri;
+int lineno;
+
+int
+objread(char *f, Triangle3 **mesh)
+{
+	Biobuf *bin;
+	char *s;
+	int idx;
+	double *coord;
+	Vector3 *vert;
+
+	bin = Bopen(f, OREAD);
+	if(bin == nil)
+		sysfatal("Bopen: %r");
+	while((s = Brdline(bin, '\n')) != nil){
+		lineno++;
+		if(*s == 'v'){
+			verts = erealloc(verts, ++nvert*sizeof(Vector3));
+			coord = (double *)(verts+nvert-1);
+			while(*s != '\n' && (Vector3 *)coord-verts < nvert){
+				while(isspace(*++s))
+					;
+				*coord++ = strtod(s, &s);
+			}
+			if(coord-(double *)(verts+nvert-1) < 3){
+				werrstr("%s:%d insufficient coordinates", f, lineno);
+				goto error;
+			}
+		}
+		if(*s == 'f'){
+			tris = erealloc(tris, ++ntri*sizeof(Triangle3));
+			vert = (Vector3 *)(tris+ntri-1);
+			while(*s != '\n' && (Triangle3 *)vert-tris < ntri){
+				while(isspace(*++s))
+					;
+				idx = strtol(s, &s, 0);
+				if(idx > nvert){
+					werrstr("%s:%d insufficient vertices", f, lineno);
+					goto error;
+				}
+				*vert++ = verts[idx-1];
+			}
+		}
+	}
+	*mesh = tris;
+	free(verts);
+	Bterm(bin);
+	return ntri;
+error:
+	free(verts);
+	free(tris);
+	Bterm(bin);
+	return -1;
+}