Keep track of the original index of a sequence of moves in one dimension. Pass it to the layout manager when moving the insertion point to prevent drifting.

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/gui/trunk@15956 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,3 +1,19 @@
+2003-02-14 17:47  Alexander Malmberg <alexander@malmberg.org>
+
+	* Headers/gnustep/gui/NSTextView.h, Source/NSTextView.m,
+	Source/NSTextView_actions.m: Keep track of the original index of a
+	sequence of moves in one dimension. Pass it to the layout manager
+	when moving the insertion point to prevent drifting.
+
+	* Source/GSHorizontalTypesetter.m (-layoutLineNewParagraph:): Fix
+	an edge case in tab handling. Also, if tabs occur and the paragraph
+	style has no more tab stops, act as if there were tabs every 100
+	points.
+
+	* Source/NSLayoutManager.m (-characterIndexMoving:fromCharacterIndex:
+	originalCharacterIndex:distance:): When moving vertically, return the
+	index of the character nearest the target horizontally.
+
 2003-02-13 01:01  Alexander Malmberg <alexander@malmberg.org>
 
 	* TextConverters/RTF/rtfGrammer.y (rtfCharset): Treat unknown

Headers/gnustep/gui/NSTextView.h

@@ -185,39 +185,33 @@ therefore be stored in the NSLayoutManager to avoid problems.
      need to be recomputed <eg, relayout>. */
   NSRect _insertionPointRect;
 
-#if 0
+  /*
-  /* This is used when you move the insertion point up or down.  The
+  This is the character index a sequence of moves in one dimension (ie.
-     system remembers the horizontal position of the insertion point
+  up/down or left/right) started at. It is passed to the layout manager
-     at the beginning of the process, and always tries to put the
+  and is used when an NSTextView is deciding where to move. (Eg.
-     insertion point in that horizontal position on each line when you
+  NSLayoutManager tries to maintain the original horizontal position when
-     go up or down.  The memory of the horizontal position is changed
+  moving up/down.)
-     as soon as you do something different from moving the cursor
+  */
-     up/down. */
+  unsigned int _originalInsertionPointCharacterIndex;
-  /* TODO: cursor movement needs to be worked out. The current methods
-  aren't good enough (eg. in a vertical layout, the original y position
-  should be preserved when moving left/right, but the original x position
-  is meaningless). A position (in the text container coordinate system)
-  based system won't work when moving through ligatures. A character based
-  system is better. A _originalCharacterIndex here should solve the problems;
-  a method:
 
-    -(unsigned int) characterIndexMoving: (int)direction
+  /*
-                                    from: (unsigned int)currentCharIndex
+  0=no information (_originalInsertionPointCharacterIndex undefined)
-                                original: (unsigned int)originalCharIndex
+  1=horizontal
+  2=vertical
+  */
+  int _currentInsertionPointMovementDirection;
 
-  should be able to give proper behavior in all cases.
+  /*
-
+  TODO:
-  Need to figure out what "proper behavior" is when moving between two
+  Still need to figure out what "proper behavior" is when moving between two
   NSTextView:s, though.
   */
-  unsigned int _originalCharIndex;
-#endif
 }
 
 
 /* Returns the default typing attributes: black text, default paragraph
 style, default user font and size. */
-+(NSDictionary*) defaultTypingAttributes; /* GNUstep extension */
++(NSDictionary *) defaultTypingAttributes; /* GNUstep extension */
 
 
 /**** Initializing ****/

Source/NSTextView.m

@@ -23,6 +23,9 @@
    Author: Pierre-Yves Rivaille <pyrivail@ens-lyon.fr>
    Date: September 2002
 
+   Extensive reworking: Alexander Malmberg <alexander@malmberg.org>
+   Date: December 2002 - February 2003
+
    This file is part of the GNUstep GUI Library.
 
    This library is free software; you can redistribute it and/or
@@ -711,6 +714,8 @@ to this method from the text container or layout manager.
       _layoutManager->_selected_range = NSMakeRange(0,0);
     }
 
+  _currentInsertionPointMovementDirection = 0;
+
   [self _updateMultipleTextViews];
 }
 
@@ -2610,6 +2615,14 @@ afterString in order over charRange.
   /* Set the new selected range */
   _layoutManager->_selected_range = charRange;
 
+  /* Clear the remembered position and direction for insertion point
+  movement.
+
+  Note that we must _not_ clear the index. Many movement actions will
+  reset the direction to a valid value, and they assume that the index
+  remains unchanged here. */
+  _currentInsertionPointMovementDirection = 0;
+
   /* TODO: when and if to restart timer <and where to stop it before> */
   [self updateInsertionPointStateAndRestartTimer: !stillSelectingFlag];
 

Source/NSTextView_actions.m

@@ -22,6 +22,9 @@
    Author: Pierre-Yves Rivaille <pyrivail@ens-lyon.fr>
    Date: September 2002
 
+   Extensive reworking: Alexander Malmberg <alexander@malmberg.org>
+   Date: December 2002 - February 2003
+
    This file is part of the GNUstep GUI Library.
 
    This library is free software; you can redistribute it and/or
@@ -723,14 +726,40 @@ added to the selection (1,3).
        select: (BOOL)select
 {
   unsigned int cindex;
+  int new_direction;
+
+  if (direction == GSInsertionPointMoveUp ||
+      direction == GSInsertionPointMoveDown)
+    {
+      new_direction = 2;
+    }
+  else if (direction == GSInsertionPointMoveLeft ||
+	   direction == GSInsertionPointMoveRight)
+    {
+      new_direction = 1;
+    }
+  else
+    {
+      new_direction = 0;
+    }
 
   cindex = [self _movementOrigin];
+  if (new_direction != _currentInsertionPointMovementDirection ||
+      !new_direction)
+    {
+      _originalInsertionPointCharacterIndex = cindex;
+    }
+  
+
   cindex = [_layoutManager characterIndexMoving: direction
 	      fromCharacterIndex: cindex
-	      originalCharacterIndex: cindex /* TODO */
+	      originalCharacterIndex: _originalInsertionPointCharacterIndex
 	      distance: distance];
   [self _moveTo: cindex
 	 select: select];
+  /* Setting the selected range will clear out the current direction, but
+  not the index. Thus, we always set the direction here. */
+  _currentInsertionPointMovementDirection = new_direction;
 }