From: André Pönitz <poenitz@gmx.net>
Date: Fri, 22 Mar 2002 09:31:26 +0000 (+0000)
Subject: fix two items from Konni's list of cursor up/down "issues"
X-Git-Tag: 1.6.10~19591
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=137aaf9cb2559db5500d34e2bc1077c6b2f02b4d;p=features.git

fix two items from Konni's list of cursor up/down "issues"


git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@3810 a592a061-630c-0410-9148-cb99ea01b6c8
---

diff --git a/src/mathed/ChangeLog b/src/mathed/ChangeLog
index 852a90d6d3..f3ab830a4c 100644
--- a/src/mathed/ChangeLog
+++ b/src/mathed/ChangeLog
@@ -1,3 +1,8 @@
+
+2002-03-12  André Pönitz <poenitz@gmx.net>
+
+	* math_cursor.C: fix some Up/Down "issues"
+
 2002-03-21  Lars Gullik Bjønnes  <larsbj@birdstep.com>
 
 	* most files: ws cleanup
diff --git a/src/mathed/math_cursor.C b/src/mathed/math_cursor.C
index 175a0157a2..86a3b12da8 100644
--- a/src/mathed/math_cursor.C
+++ b/src/mathed/math_cursor.C
@@ -1175,6 +1175,9 @@ MathCursorPos const & MathCursor::cursor() const
 
 bool MathCursor::goUpDown(bool up)
 {
+	// Be warned: The 'logic' implemented in this function is highly fragile.
+	// A distance of one pixel or a '<' vs '<=' _really_ matters.
+	// So fiddle around with it only if you know what you are doing!
 	int xlow, xhigh, ylow, yhigh;
 
   int xo, yo;
@@ -1219,8 +1222,10 @@ bool MathCursor::goUpDown(bool up)
 
 	// try to find an inset that knows better then we
 	while (1) {
-		// we found a cell that thinks it has something "below" us.
+		///lyxerr << "updown: We are in " << *par() << " idx: " << idx() << '\n';
+		// ask inset first
 		if (par()->idxUpDown(idx(), up)) {
+			// we found a cell that thinks it has something "below" us.
 			///lyxerr << "updown: found inset that handles UpDown\n";
 			xarray().boundingBox(xlow, xhigh, ylow, yhigh);
 			// project (xo,yo) onto proper box
@@ -1235,6 +1240,7 @@ bool MathCursor::goUpDown(bool up)
 			return true;
 		}
 
+		// leave inset
 		if (!popLeft()) {
 			// no such inset found, just take something "above"
 			///lyxerr << "updown: handled by strange case\n";
@@ -1246,7 +1252,12 @@ bool MathCursor::goUpDown(bool up)
 					up ? yo - 4 : formula()->yhigh()
 				);
 		}
-		///lyxerr << "updown: looping\n";
+		
+		// any improvement so far?
+		int xnew, ynew;
+		getPos(xnew, ynew);
+		if (up ? ynew < yo : ynew > yo)
+			return true;
 	}
 }
 
@@ -1267,7 +1278,9 @@ bool MathCursor::bruteFind
 			int yo = top.ypos();
 			if (xlow <= xo && xo <= xhigh && ylow <= yo && yo <= yhigh) {
 				double d = (x - xo) * (x - xo) + (y - yo) * (y - yo);
-				if (d < best_dist) {
+				// '<=' in order to take the last possible position
+				// this is important for clicking behind \sum in e.g. '\sum_i a'
+				if (d <= best_dist) {
 					best_dist   = d;
 					best_cursor = it.cursor();
 				}