diff -urN rt_v58/cross.c rt_v59/cross.c
--- rt_v58/cross.c	2018-06-29 09:20:42.000000000 +0900
+++ rt_v59/cross.c	2018-07-06 03:39:31.000000000 +0900
@@ -334,19 +334,27 @@
 	if(kind_idx != KIND_BALL){
 		double *p = ret->l_nv_g.p;
 		double *v = ret->l_nv_g.v;
-		double z[3];
+		double x[3], z[3];
 		struct vecs vs;
 	
 		if(is_plane(kind_idx)){
 			v_set(z, v_x1);
 		}else if(kind_idx == KIND_PIPE_SIDE){
-			v_add(p, v_z1, z);
-		}else{ /* KIND_CONE_SIDE */
 			v_set(z, v_z1);
+		}else{ /* KIND_CONE_SIDE */
+			v_sub(v_z1, ret->p, z);
 		}
+		vecs_by_fix_ref(&vs, 'z', z, 'y', nv);
+		v_set( x, vecs_get_by_name(&vs, 'x') );
+
+		v_add(x, ret->p, x);
+		v_add(z, ret->p, z);
+		lstx_tr_p(l2g, L2G, x, x);
 		lstx_tr_p(l2g, L2G, z, z);
+		v_sub(x, p, x);
 		v_sub(z, p, z);
-		vecs_by_fix_ref(&vs, 'z', z, 'y', v);
+		vecs_by_fix_ref(&vs, 'x', x, 'z', z);
+		v_set( v, vecs_get_by_name(&vs, 'y') );
 	}
 
 	if(rev){