Index: trunk/src/obj_line.h
===================================================================
--- trunk/src/obj_line.h	(revision 24048)
+++ trunk/src/obj_line.h	(revision 24049)
@@ -100,18 +100,24 @@
 
 void pcb_line_enforce_drc(void);
 
-/* Checks for intersectors against two lines and
- * adjusts the end point until there is no intersection or
- * it winds up back at the start. If way is pcb_false it checks
- * an ortho start line with one 45 refraction to reach the endpoint,
- * otherwise it checks a 45 start, with a ortho refraction to reach endpoint
- *
- * It returns the straight-line length of the best answer, and
- * changes the position of 'end' to the best answer.
- */
-double pcb_drc_lines(const pcb_point_t *start, pcb_point_t *end, pcb_bool way);
+/* Calculate a pair of refractioned (ortho-45) lines between 'start' and 'end'.
+   If 'mid_out' is not NULL, load it with the coords of the middle point.
+   If way is false it checks an ortho start line with one 45 refraction to
+   reach the endpoint, otherwise it checks a 45 start, with a ortho refraction
+   to reach endpoint.
 
+   Checks for intersectors against two lines.
 
+   If optimize is false, return straight-line distance between start and end
+   on success or -1 if the pair-of-lines has hit a blocker object.
+
+   If optimize is true, keep on looking for a mid-way solution, adjusting
+   the fields of 'end' needed to find the closest point to the original target
+   that still won't hit any object. Returns the straigh-line distance between
+   start and the new end. */
+double pcb_drc_lines(const pcb_point_t *start, pcb_point_t *end, pcb_point_t *mid_out, pcb_bool way, pcb_bool optimize);
+
+
 /* Rather than mode the line bounding box, we set it so the point bounding
  * boxes are updated too.
  */
Index: trunk/src/obj_line_drcenf.c
===================================================================
--- trunk/src/obj_line_drcenf.c	(revision 24048)
+++ trunk/src/obj_line_drcenf.c	(revision 24049)
@@ -228,7 +228,7 @@
 	return PCB_R_DIR_FOUND_CONTINUE;
 }
 
-double pcb_drc_lines(const pcb_point_t *start, pcb_point_t *end, pcb_bool way)
+double pcb_drc_lines(const pcb_point_t *start, pcb_point_t *end, pcb_point_t *mid_out, pcb_bool way, pcb_bool optimize)
 {
 	double f, s, f2, s2, len, best;
 	pcb_coord_t dx, dy, temp, last, length;
@@ -383,10 +383,21 @@
 			f -= s;
 		s *= 0.5;
 		length = MIN(f * temp, temp);
+		if (!optimize) {
+			if (blocker)
+				best = -1;
+			else
+				best = length;
+			break;
+		}
 	}
 
 	end->X = ans.X;
 	end->Y = ans.Y;
+	if (mid_out != NULL) {
+		mid_out->X = line1.Point2.X;
+		mid_out->Y = line1.Point2.Y;
+	}
 	return best;
 }
 
@@ -472,9 +483,9 @@
 
 	if (conf_core.editor.line_refraction != 0) {
 		/* first try starting straight */
-		r1 = pcb_drc_lines(&start, &rs, pcb_false);
+		r1 = pcb_drc_lines(&start, &rs, NULL, pcb_false, pcb_true);
 		/* then try starting at 45 */
-		r2 = pcb_drc_lines(&start, &r45, pcb_true);
+		r2 = pcb_drc_lines(&start, &r45, NULL, pcb_true, pcb_true);
 	}
 	else {
 		drc_line(&rs);