Fix arrow damage with highlightDragging XB

With highlight dragging the highlights of the previous moves are cleared
when lifting the piece. Logically, this should also clear the arrow, but
to do that requires a board redraw, which is not done at this stage. (And
even then this would only be effective after marking the arrow damage,
which is not done yet either). As a temporary fix, we repair the arrow
by redrawing it.
  This patch has moved marking of the arrow damage from DrawArrowHighlight
to a separate routine, so a future better fix can also call that when the
arrow should be erased.

diff --git a/xboard.c b/xboard.c
index 559843c..f05027d 100644 (file)
--- a/xboard.c
+++ b/xboard.c
@@ -4213,6 +4213,8 @@ SetHighlights (int fromX, int fromY, int toX, int toY)
            drawHighlight(toX, toY, highlineGC);
        }
     }
+    if(toX<0) // clearing the highlights must have damaged arrow
+       DrawArrowHighlight(hi1X, hi1Y, hi2X, hi2Y); // for now, redraw it (should really be cleared!)
     hi1X = fromX;
     hi1Y = fromY;
     hi2X = toX;
@@ -8590,11 +8592,25 @@ DrawArrowBetweenPoints (int s_x, int s_y, int d_x, int d_y)
 //    Polygon( hdc, arrow, 7 );
 }
 
+void
+ArrowDamage (int s_col, int s_row, int d_col, int d_row)
+{
+    int hor, vert, i;
+    hor = 64*s_col + 32; vert = 64*s_row + 32;
+    for(i=0; i<= 64; i++) {
+            damage[0][vert+6>>6][hor+6>>6] = True;
+            damage[0][vert-6>>6][hor+6>>6] = True;
+            damage[0][vert+6>>6][hor-6>>6] = True;
+            damage[0][vert-6>>6][hor-6>>6] = True;
+            hor += d_col - s_col; vert += d_row - s_row;
+    }
+}
+
 /* [AS] Draw an arrow between two squares */
 void
 DrawArrowBetweenSquares (int s_col, int s_row, int d_col, int d_row)
 {
-    int s_x, s_y, d_x, d_y, hor, vert, i;
+    int s_x, s_y, d_x, d_y;
 
     if( s_col == d_col && s_row == d_row ) {
         return;
@@ -8631,15 +8647,7 @@ DrawArrowBetweenSquares (int s_col, int s_row, int d_col, int d_row)
     A_WIDTH = squareSize / 14.; //[HGM] make float
 
     DrawArrowBetweenPoints( s_x, s_y, d_x, d_y );
-
-    hor = 64*s_col + 32; vert = 64*s_row + 32;
-    for(i=0; i<= 64; i++) {
-            damage[0][vert+6>>6][hor+6>>6] = True;
-            damage[0][vert-6>>6][hor+6>>6] = True;
-            damage[0][vert+6>>6][hor-6>>6] = True;
-            damage[0][vert-6>>6][hor-6>>6] = True;
-            hor += d_col - s_col; vert += d_row - s_row;
-    }
+    ArrowDamage(s_col, s_row, d_col, d_row);
 }
 
 Boolean