diff --git a/slicer/stl.c b/slicer/stl.c
index 6e1f80e..1590f50 100644
--- a/slicer/stl.c
+++ b/slicer/stl.c
@@ -1,8 +1,8 @@
 /*
  * stl.c - STL file reading
  *
- * Written 2014 by Werner Almesberger
- * Copyright 2014 by Werner Almesberger
+ * Written 2014-2015 by Werner Almesberger
+ * Copyright 2014-2015 by Werner Almesberger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,6 @@
 #include <string.h>
 #include <math.h>
 
-#include "mesh.h"
 #include "stl.h"
 
 
@@ -34,18 +33,16 @@ enum state {
 };
 
 
-void stl_load_file(FILE *file)
+void stl_load_file(FILE *file, void (*facet)(struct v f[3]))
 {
-	char buf[MAX_LINE+1];
+	char buf[MAX_LINE + 1];
 	enum state state = s_init;
-	const struct vertex *v[3];
+	struct v f[3];
 	int num_v = 0;
 	char *s, *e;
 	int n = 0;
 	int end, got;
-	float x, y, z;
 
-	mesh_init();
 	while (fgets(buf, sizeof(buf), file)) {
 		n++;
 		if (!(n & 1023))
@@ -75,13 +72,12 @@ void stl_load_file(FILE *file)
 			num_v = 0;
 			break;
 		case s_vertices:
-			got = sscanf(s, "vertex %f %f %f%n", &x,&y, &z, &end);
+			got = sscanf(s, "vertex %f %f %f%n",
+			    &f[num_v].x, &f[num_v].y, &f[num_v].z, &end);
 			if (got < 3)
 				break;
-			v[num_v] = vertex_add(
-			    roundf(x*1000), roundf(-y*1000), roundf(z*1000));
 			if (++num_v == 3) {
-				facet_add(v[0], v[1], v[2]);
+				facet(f);
 				state = s_endloop;
 			}
 			break;
@@ -94,9 +90,9 @@ void stl_load_file(FILE *file)
 			state = s_facet;
 			break;
 		}
-		if (end != e-s) {
+		if (end != e - s) {
 			fprintf(stderr, "cannot parse line %d (%d %ld)\n",
-			     n, end, e-s);
+			     n, end, e - s);
 			exit(1);
 		}
 	}
@@ -106,7 +102,7 @@ void stl_load_file(FILE *file)
 }
 
 
-void stl_load(const char *name)
+void stl_load(const char *name, void (*facet)(struct v f[3]))
 {
 	FILE *file;
 
@@ -115,6 +111,6 @@ void stl_load(const char *name)
 		perror(name);
 		exit(1);
 	}
-	stl_load_file(file);
+	stl_load_file(file, facet);
 	fclose(file);
 }
diff --git a/slicer/stl.h b/slicer/stl.h
index e1db1c4..3575dc9 100644
--- a/slicer/stl.h
+++ b/slicer/stl.h
@@ -1,8 +1,8 @@
 /*
  * stl.h - STL file reading
  *
- * Written 2014 by Werner Almesberger
- * Copyright 2014 by Werner Almesberger
+ * Written 2014-2015 by Werner Almesberger
+ * Copyright 2014-2015 by Werner Almesberger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,7 +17,12 @@
 #include <stdio.h>
 
 
-void stl_load_file(FILE *file);
-void stl_load(const char *name);
+struct v {
+	float x, y, z;
+};
+
+
+void stl_load_file(FILE *file, void (*facet)(struct v f[3]));
+void stl_load(const char *name, void (*facet)(struct v f[3]));
 
 #endif /* !STL_H */