X-Git-Url: http://winboard.nl/cgi-bin?a=blobdiff_plain;f=backend.c;h=ae1eba1638ff9e20029a729abe9046c91fca8098;hb=7e57e463246f702af0f6423eecda619a1ae28df0;hp=f4ac7f90ad9774e47ffa81b294b63b31976e3833;hpb=09b61995c50278b6a11a159a54d24ea38ac88e87;p=xboard.git

diff --git a/backend.c b/backend.c
index f4ac7f9..ae1eba1 100644
--- a/backend.c
+++ b/backend.c
@@ -888,7 +888,7 @@ void
 Load(ChessProgramState *cps, int i)
 {
     char *p, *q, buf[MSG_SIZ], command[MSG_SIZ], buf2[MSG_SIZ];
-    if(engineLine[0]) { // an engine was selected from the combo box
+    if(engineLine && engineLine[0]) { // an engine was selected from the combo box
 	snprintf(buf, MSG_SIZ, "-fcp %s", engineLine);
 	SwapEngines(i); // kludge to parse -f* / -first* like it is -s* / -second*
 	ParseArgsFromString(resetOptions); appData.fenOverride[0] = NULL;
@@ -5140,7 +5140,7 @@ int PromoScroll(int x, int y)
   int step = 0;
 
   if(promoSweep == EmptySquare || !appData.sweepSelect) return FALSE;
-  if(abs(x - lastX) < 15 && abs(y - lastY) < 15) return FALSE;
+  if(abs(x - lastX) < 25 && abs(y - lastY) < 25) return FALSE;
   if( y > lastY + 2 ) step = -1; else if(y < lastY - 2) step = 1;
   if(!step) return FALSE;
   lastX = x; lastY = y;
@@ -5468,11 +5468,11 @@ UnLoadPV()
 void
 MovePV(int x, int y, int h)
 { // step through PV based on mouse coordinates (called on mouse move)
-  int margin = h>>3, step = 0;
+  int margin = h>>3, step = 0, threshold = (pieceSweep == EmptySquare ? 10 : 15);
 
   // we must somehow check if right button is still down (might be released off board!)
   if(endPV < 0 && pieceSweep == EmptySquare) return; // needed in XBoard because lastX/Y is shared :-(
-  if(abs(x - lastX) < 7 && abs(y - lastY) < 7) return;
+  if(abs(x - lastX) < threshold && abs(y - lastY) < threshold) return;
   if( y > lastY + 2 ) step = -1; else if(y < lastY - 2) step = 1;
   if(!step) return;
   lastX = x; lastY = y;