pathedit.cpp

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// $Id: pathedit.cpp 1282 2006-06-09 09:46:49Z alex $
/* @@tag:xara-cn@@ DO NOT MODIFY THIS LINE
================================XARAHEADERSTART===========================
 
               Xara LX, a vector drawing and manipulation program.
                    Copyright (C) 1993-2006 Xara Group Ltd.
       Copyright on certain contributions may be held in joint with their
              respective authors. See AUTHORS file for details.

LICENSE TO USE AND MODIFY SOFTWARE
----------------------------------

This file is part of Xara LX.

Xara LX is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License version 2 as published
by the Free Software Foundation.

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-----------------

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The additional rights are to use, modify, and distribute the software
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=================================XARAHEADEREND============================
 */
// Contains general purpose operations to be used in path editing

/*
*/

#include "camtypes.h"
#include "pathedit.h"

// Code headers
//#include "app.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "attrmgr.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "blobs.h"
#include "csrstack.h"
//#include "cursor.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "document.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "docview.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "fixmem.h"               // for CCMalloc and CCFree - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "group.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "lineattr.h"           // for getting the line width of a NodePath
#include "nodepath.h"
#include "ndtxtpth.h"
//#include "nodeattr.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "objchge.h"
#include "pathops.h"
#include "progress.h"
//#include "tool.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "tranform.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "attrmap.h"
//#include "spread.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "bubbleid.h"
#include "ndbldpth.h"
#include "nodeblnd.h"
//#include "blndtool.h"
#include "nodebldr.h"
#include "opdrbrsh.h"
// Resource headers
#include "helpids.h"
//#include "jim.h"
//#include "peter.h"
//#include "resource.h"    
//#include "barsdlgs.h"
//#include "rik.h"
//#include "simon.h"
//#include "viewrc.h"
//#include "phil.h"
//#include "becomea.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "brshattr.h"
#include "opbevel.h"
#include "nodemold.h"
#include "ndmldpth.h"
#include "samplist.h"
#include "brshattr.h"
#include "ophist.h"
#include "blndtool.h"

#define PATRACE if(IsUserName("Peter")) TRACE

// Useful macro, given a pointer to a CCObject (or an object derived
// from it) and a string format, it will output the class name of the object. 
// Example usage PACLASSNAME(CurrentNode,"Node class = %s\n");
// N.B. No checking is node or parameters.  Note semi-colon on end.
#define PACLASSNAME(a,b) CCRuntimeClass* Blob; Blob = a->GetRuntimeClass(); PATRACE(b,Blob->m_lpszClassName)

// Operations
CC_IMPLEMENT_DYNCREATE( OpJoinShapes, SelOperation)
CC_IMPLEMENT_DYNCREATE( OpBreakShapes, SelOperation) 
CC_IMPLEMENT_DYNCREATE( OpDeletePoints, SelOperation)       // Deleting of path endpoints
CC_IMPLEMENT_DYNCREATE( OpNodePathEditBlob, SelOperation)   // Dragging of a path endpoint
CC_IMPLEMENT_DYNCREATE( OpToggleSmooth, SelOperation)       // Toggling smooth/cuspness of endpoints
CC_IMPLEMENT_DYNCREATE( OpNodePathEditControlBlob, OpNodePathEditBlob)  // Dragging of a Bezier control point
CC_IMPLEMENT_DYNCREATE( OpReshapeOrAddPoint, OpNodePathEditBlob)        // Reshaping a path OR adding an endpoint
CC_IMPLEMENT_DYNCREATE( OpNodePathAddEndpoint, OpNodePathEditBlob)      // Adding an endpoint to the end of the path
CC_IMPLEMENT_DYNCREATE( OpNewPath, OpNodePathEditBlob)
CC_IMPLEMENT_DYNCREATE( OpCloseNodePaths, OpNodePathAddEndpoint)        // Closing all selected open paths

// Actions
CC_IMPLEMENT_DYNCREATE( ModifyPathAction, Action)
CC_IMPLEMENT_DYNCREATE( RemovePathElementAction, Action)
CC_IMPLEMENT_DYNCREATE( InsertPathElementAction, Action)
CC_IMPLEMENT_DYNCREATE( ModifyElementAction, Action)
CC_IMPLEMENT_DYNCREATE( ModifyFlagsAction, Action)
CC_IMPLEMENT_DYNCREATE( RecalcBoundsAction, Action)
CC_IMPLEMENT_DYNCREATE( RecordBoundsAction, Action)
CC_IMPLEMENT_DYNCREATE( ModifyFilledAction, Action)
CC_IMPLEMENT_DYNCREATE( SavePathArraysAction, Action)
//CC_IMPLEMENT_DYNCREATE( StorePathSubSelStateAction, Action)

// Declare smart memory handling in Debug builds
#define new CAM_DEBUG_NEW

/********************************************************************************************

>   OpNodePathEditBlob::OpNodePathEditBlob()

    Author:     Rik_Heywood (Xara Group Ltd) <camelotdev@xara.com>
    Created:    20/7/93
    Purpose:    Constructor. This simply sets a few of the operation flags.

********************************************************************************************/

OpNodePathEditBlob::OpNodePathEditBlob()
{
    EndSnapped = FALSE; 
    SnapToAnother = FALSE;  
    pMoveCursor = NULL;
    SnapToPath = NULL;
    DragStarted = FALSE;
    SnapToLineOrCurve = FALSE;
    DragPoint = -1;
    UpdatePoint = -1;
    ConstrainPoint = DocCoord(-1,-1);
    ConstrainPrevPoint = DocCoord(-1,-1);
    ConstrainNextPoint = DocCoord(-1,-1);
    MultiplePaths = FALSE;
}

/********************************************************************************************

>   void OpNodePathEditBlob::DoStartDragEdit(NodePath* OrigPath, DocCoord Anchor, Spread *pSpread)

    Author:     Rik_Heywood (Xara Group Ltd) <camelotdev@xara.com> - latterly Peter
    Created:    5/7/93
    Inputs:     OrigPath - Pointer to the path we are about to edit
                Anchor - The position of the mouse at the start of the Drag
                pSpread - The spread that the path is on
    Purpose:    This is called to start a drag operation on an endpoint on a path

********************************************************************************************/

void OpNodePathEditBlob::DoStartDragEdit(NodePath* OrigPath, DocCoord Anchor, Spread *pSpread)
{
    BOOL Success = TRUE;
    
    // We had better take a note of the starting point of the drag
    LastMousePos = Anchor;
    StartMousePos = Anchor;
    StartSpread  = pSpread;

    SelRange* theSelection = GetApplication ()->FindSelection ();

    BOOL selectionContainsMoulds = FALSE;

    if (theSelection)
    {
        // we need to do some special processing to handle moulds ....

        Node* pCurrentNode = (Node*) theSelection->FindFirst ();

        while (pCurrentNode)
        {
            if (IS_A (pCurrentNode, NodeMould))
            {
                selectionContainsMoulds = TRUE;
                pCurrentNode = NULL;
            }
            else
            {
                pCurrentNode = (Node*) theSelection->FindNext (pCurrentNode);
            }
        }
    }

    if (!selectionContainsMoulds)
    {
        BevelTools::BuildListOfSelectedNodes(&OriginalPaths, CC_RUNTIME_CLASS(NodePath));
    }
    else
    {
        // now go and get those moulds baby !
        BevelTools::BuildListOfSelectedNodes(&OriginalPaths, CC_RUNTIME_CLASS(NodeMouldPath));

        // now, we also have to rescan the selection (again!) BUT this time without
        // the moulds

        Node* pCurrentNode = (Node*) theSelection->FindFirst ();

        while (pCurrentNode)
        {
            if (IS_A (pCurrentNode, NodeMould))
            {
                pCurrentNode = (Node*) theSelection->FindNext (pCurrentNode);
            }
            else
            {
                if (IS_A (pCurrentNode, NodePath))
                {
                    NodeListItem* pInsert = new NodeListItem ();
                    
                    if (pInsert)    // and insert into the paths list ....
                    {
                        pInsert->pNode = pCurrentNode;
                        OriginalPaths.AddHead (pInsert);
                    }
                }
                
                pCurrentNode = (Node*) theSelection->FindNext (pCurrentNode);
            }
        }
    }

    if (OriginalPaths.GetCount () == 1)
    //if (TRUE)
    {
        MultiplePaths = FALSE;
        
        OriginalPath = OrigPath;

        // Now calculate DragPoint and UpdatePoint
        if (Success)
        {
            PathFlags* Flags = OriginalPath->InkPath.GetFlagArray();
            PathVerb* Verbs = OriginalPath->InkPath.GetVerbArray();
            INT32 NumCoords = OriginalPath->InkPath.GetNumCoords();

            for (INT32 i=0;i<NumCoords;i++)
            {
                if (Flags[i].IsEndPoint && Flags[i].IsSelected 
                                && !(OriginalPath->InkPath.IsSubPathClosed(i) && (Verbs[i] == PT_MOVETO)) )
                {
                    // If you are dragging a closepoint then you are actually dragging two points
                    // but we need to update the line tool as the user thinks they are dragging one.
                    // If we are on the opening moveto then just skip the tests.
                    if (DragPoint != -1)
                    {
                        UpdatePoint = -1;
                        DragPoint = -1;
                        break;
                    }
                    else
                    {
                        UpdatePoint = i;
                        DragPoint = i;
                    }
                }
            }
            // On exit from that loop, DragPoint = -1 if there are multiple selected endpoints,
            // otherwise DragPoint is the index to the selected endpoint.  UpdatePoint is the
            // index of the point displaied in the Line tool
        }

        // Set the constrain point
        if (DragPoint != -1)
        {
            ConstrainPoint = OriginalPath->InkPath.GetCoordArray()[DragPoint];

            // Get the previous endpoint
            INT32 OtherEndpoint = DragPoint;
            if (OriginalPath->InkPath.FindPrevEndPoint(&OtherEndpoint))
                ConstrainPrevPoint = OriginalPath->InkPath.GetCoordArray()[OtherEndpoint];
            else
                ConstrainPrevPoint = ConstrainPoint;

            // Get the next endpoint
            OtherEndpoint = DragPoint;
            if (OriginalPath->InkPath.FindNextEndPoint(&OtherEndpoint))
                ConstrainNextPoint = OriginalPath->InkPath.GetCoordArray()[OtherEndpoint];
            else
                ConstrainNextPoint = ConstrainPoint;
        }
        else
        {
            ConstrainPoint = Anchor;
            ConstrainPrevPoint = Anchor;
            ConstrainNextPoint = Anchor;
        }

        // We also need to make a version of the path that we can change
        Success = BuildEditPath();

        // Create and send a change message about this path edit
        // This one is handled by moulds in their OnChildChange() function
        if (Success)
            Success = (EditObjChange.ObjChangeStarting(OrigPath,this,&EditPath,StartSpread,TRUE) == CC_OK);

        // Create and display the cursors for this operation
        if (Success)
            Success = CreateCursors();
        if (Success)
            ChangeCursor(pCrossHairCursor);
        
    //  // Render the bits of the path that are different
        DocRect EditPathBBox = EditPath.GetBoundingRect();
    //  if (Success)
    //      RenderPathEditBlobs(EditPathBBox, pSpread);

        // Tell the Dragging system that we need drags to happen
        if (Success)
            Success = StartDrag(DRAGTYPE_AUTOSCROLL, &EditPathBBox, &LastMousePos);

        if (!Success)
        {
            InformError();
            FailAndExecute();
            End();
        }
    }
    else
    {
        // lets try and keep things the same for the blobs parent as in the one selection case
        // BUT lets also try and do our extra stuff ....  I expect time MUCK UPS to occur !!!!

        MultiplePaths = TRUE;
        
        OriginalPath = OrigPath;

        // we need to make OrigPath the first one in our linked list ....

        NodeListItem* pCurrentOrig = (NodeListItem*) OriginalPaths.GetHead ();

        while (pCurrentOrig)
        {
            NodePath* pOrigPath = (NodePath*) (pCurrentOrig->pNode);

            if (pOrigPath == OrigPath)
            {
                NodeListItem* newHead = (NodeListItem*) OriginalPaths.RemoveItem (pCurrentOrig);
                
                OriginalPaths.AddHead (newHead);

                pCurrentOrig = NULL;
            }
            else
            {
                pCurrentOrig = (NodeListItem*) OriginalPaths.GetNext (pCurrentOrig);
            }
        }

        // Now calculate DragPoint and UpdatePoint
        if (Success)
        {
            NodeListItem* pCurrentOrig = (NodeListItem*) OriginalPaths.GetHead ();

            // CGS:  while loop taken out since we can only be 'drag sensitive' to the point
            // that is actually being dragged

            //while (pCurrentOrig)
            {
                NodePath* pOrigPath = (NodePath*) (pCurrentOrig->pNode);
                
                PathFlags* Flags = pOrigPath->InkPath.GetFlagArray();
                PathVerb* Verbs = pOrigPath->InkPath.GetVerbArray();
                INT32 NumCoords = pOrigPath->InkPath.GetNumCoords();

                for (INT32 i=0;i<NumCoords;i++)
                {
                    if (Flags[i].IsEndPoint && Flags[i].IsSelected 
                                    && !(pOrigPath->InkPath.IsSubPathClosed(i) && (Verbs[i] == PT_MOVETO)) )
                    {
                        // If you are dragging a closepoint then you are actually dragging two points
                        // but we need to update the line tool as the user thinks they are dragging one.
                        // If we are on the opening moveto then just skip the tests.
                        if (DragPoint != -1)
                        {
                            UpdatePoint = -1;
                            DragPoint = -1;
                            break;
                        }
                        else
                        {
                            UpdatePoint = i;
                            DragPoint = i;
                        }
                    }
                }

            //  pCurrentOrig = (NodeListItem*) OriginalPaths.GetNext (pCurrentOrig);
            }
            // On exit from that loop, DragPoint = -1 if there are multiple selected endpoints,
            // otherwise DragPoint is the index to the selected endpoint.  UpdatePoint is the
            // index of the point displaied in the Line tool
        }

        // Set the constrain point - do this only for the path that was clicked on
        // Any guesses as to why?

        // Answer:  cause its the one that is being dragged!
        if (DragPoint != -1)
        {
            NodeListItem* pCurrentOrig = (NodeListItem*) OriginalPaths.GetHead ();
            NodePath* pOrigPath = (NodePath*) (pCurrentOrig->pNode);
            
            ConstrainPoint = pOrigPath->InkPath.GetCoordArray()[DragPoint];

            // Get the previous endpoint
            INT32 OtherEndpoint = DragPoint;
            if (pOrigPath->InkPath.FindPrevEndPoint(&OtherEndpoint))
                ConstrainPrevPoint = pOrigPath->InkPath.GetCoordArray()[OtherEndpoint];
            else
                ConstrainPrevPoint = ConstrainPoint;

            // Get the next endpoint
            OtherEndpoint = DragPoint;
            if (pOrigPath->InkPath.FindNextEndPoint(&OtherEndpoint))
                ConstrainNextPoint = pOrigPath->InkPath.GetCoordArray()[OtherEndpoint];
            else
                ConstrainNextPoint = ConstrainPoint;
        }
        else
        {
            ConstrainPoint = Anchor;
            ConstrainPrevPoint = Anchor;
            ConstrainNextPoint = Anchor;
        }

        // We also need to make versions of the paths that we can change
        Success = BuildEditPaths();

        // Create and send a change message about this path edit
        // This one is handled by moulds in their OnChildChange() function
        if (Success)
        {
            NodeListItem* pCurrentOrig = (NodeListItem*) OriginalPaths.GetHead ();
            NodeListItem* pCurrentEdit = (NodeListItem*) EditPaths.GetHead ();

            while ((pCurrentOrig) && (pCurrentEdit))
            {
                NodePath* pOrigPath = (NodePath*) (pCurrentOrig->pNode);
                Path* pEditPath = (Path*) (pCurrentEdit->pNode);
                
                
                ObjChangePathEdit* NewEditObjChange = new ObjChangePathEdit;
                
                Success = (NewEditObjChange->ObjChangeStarting(pOrigPath,this,pEditPath,StartSpread,TRUE) == CC_OK);

                NodeListItem* pInsert = new NodeListItem;
                pInsert->pNode = (Node*) NewEditObjChange;
        
                ObjChanges.AddTail (pInsert);


                BOOL* NewDragStartVal = new BOOL;
                *NewDragStartVal = FALSE;
                
                NodeListItem* pInsert2 = new NodeListItem;
                pInsert2->pNode = (Node*) NewDragStartVal;

                PathsDragStarted.AddTail (pInsert2);


                if (Success)
                {
                    pCurrentOrig = (NodeListItem*) OriginalPaths.GetNext (pCurrentOrig);
                    pCurrentEdit = (NodeListItem*) EditPaths.GetNext (pCurrentEdit);
                }
                else
                {
                    pCurrentOrig = NULL;
                    pCurrentEdit = NULL;
                }

                
                //delete (NewEditObjChange);
        //      delete (NewDragStartVal);
            }
        }

        // Create and display the cursors for this operation (only once - obviously)
        if (Success)
            Success = CreateCursors();
        if (Success)
            ChangeCursor(pCrossHairCursor);
        
    //  // Render the bits of the path that are different
        DocRect EditPathBBox;// = EditPath.GetBoundingRect();

        SelRange* Selected = GetApplication()->FindSelection();

        EditPathBBox = Selected->GetBlobBoundingRect ();

    //  if (Success)
    //      RenderPathEditBlobs(EditPathBBox, pSpread);

        // Tell the Dragging system that we need drags to happen
        if (Success)
            Success = StartDrag(DRAGTYPE_AUTOSCROLL, &EditPathBBox, &LastMousePos);

        if (!Success)
        {
            InformError();
            FailAndExecute();
            End();
        }
    }
}



/********************************************************************************************

>   void OpNodePathEditBlob::DragPointerMove( DocCoord PointerPos, ClickModifiers ClickMods, Spread*, BOOL bSolidDrag)

    Author:     Rik_Heywood (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/7/93
    Inputs:     PointerPos - The current position of the mouse in Doc Coords
                ClickMods - Which key modifiers are being pressed
    Purpose:    This is called every time the mouse moves, during a drag.
    SeeAlso:    ClickModifiers

********************************************************************************************/

void OpNodePathEditBlob::DragPointerMove( DocCoord PointerPos, ClickModifiers ClickMods, Spread *pSpread, BOOL bSolidDrag)
{
    if (!MultiplePaths)
    {
        // If drag has moved onto a different spread, convert the coord to be relative to the
        // original spread.
        if (pSpread != StartSpread)
            PointerPos = MakeRelativeToSpread(StartSpread, pSpread, PointerPos);

        Path TempPath;

        // inform the parent a change is happening
        if (EditObjChange.ChangeMask.EorBlobs)
        {
            ChangeCode Chge = EditObjChange.RenderCurrentBlobs(OriginalPath,this,&EditPath,StartSpread,TRUE);
            if (Chge!=CC_OK)
                return;
            // Create a local copy of the edit path
            if (!TempPath.Initialise(EditPath.GetNumCoords(), 12))
                return;
            TempPath.CopyPathDataFrom(&EditPath);
        }

        // Rub out the old EORed version of the path
        if (DragStarted)
            RenderPathEditBlobs( EditPath.GetBoundingRect(), StartSpread );
        else
            DragStarted = TRUE;

        // Here is where we do all the snapping to grids and endpoints
        // and constrain. First we check for snapping to line ends, then
        // we check constrain, then we check grid snapping

        EndSnapped = FALSE;         // TRUE if this point snaps to the other end
        SnapToAnother = FALSE;      // TRUE if this point snaps to another line end
        SnapToLineOrCurve = FALSE;  // No snapped other line

        // We might be snapping to an endpoint if the point we're dragging around is either
        // a moveto, or is the last point in the subpath. We will also only snap if there is
        // only one point selected on the path

        DocRect PointerBlobRect;
        GetApplication()->GetBlobManager()->GetBlobRect(PointerPos,&PointerBlobRect);

        DocCoord* Coords = EditPath.GetCoordArray();
//      PathFlags* Flags = EditPath.GetFlagArray();
        PathVerb* Verbs = EditPath.GetVerbArray();
        INT32 NumCoords = EditPath.GetNumCoords();

        INT32 i;
        if (DragPoint != -1)
        {
            // Look to see if the selected point is a real endpoint
            if (Verbs[DragPoint] == PT_MOVETO)
            {
                // This is the start element of the path
                i = DragPoint;
                if (!EditPath.IsSubPathClosed(i))
                {
                    INT32 NextEndpoint = i;
                    if (EditPath.FindNextEndPoint(&NextEndpoint))
                    {
                        EditPath.FindEndElOfSubPath(&i);        // i indexes to the end element

                        // If this sub-path is one element long then closing it is not allowed
                        if ((i != NextEndpoint) && PointerBlobRect.ContainsCoord(Coords[i]))
                        {
                            PointerPos.x = Coords[i].x + LastMousePos.x - Coords[DragPoint].x;
                            PointerPos.y = Coords[i].y + LastMousePos.y - Coords[DragPoint].y;
                            EndSnapped = TRUE;
                        }
                    }
                }
            }
            else if (DragPoint+1 == NumCoords || Verbs[DragPoint+1] == PT_MOVETO)
            {
                // This is the last element in the sub-path
                i = DragPoint;
                if (!EditPath.IsSubPathClosed(i))
                {
                    INT32 PrevEndpoint = i;
                    if (EditPath.FindPrevEndPoint(&PrevEndpoint))
                    {
                        EditPath.FindStartOfSubPath(&i);            // i is the index of the start of the sub-path
            
                        // If this sub-path is one element long then closing it is not allowed
                        if ((i != PrevEndpoint) && PointerBlobRect.ContainsCoord(Coords[i]))
                        {
                            PointerPos.x = Coords[i].x + LastMousePos.x - Coords[DragPoint].x;
                            PointerPos.y = Coords[i].y + LastMousePos.y - Coords[DragPoint].y;
                            EndSnapped = TRUE;
                        }
                    }
                }
            }
        }
        
        // That detects snapping to the opposite endpoint, but what about snapping to another
        // endpoint altogether? Time to check for that eventuality
        if (!EndSnapped && DragPoint != -1 && (Verbs[DragPoint] == PT_MOVETO || DragPoint+1 == NumCoords || Verbs[DragPoint+1] == PT_MOVETO) )
        {
            // Get a snapshot of the selection
            SelRange* Selected = GetApplication()->FindSelection();
            Node* pNode = Selected->FindFirst();
            INT32 SubIndex,SubEnd;
            while (pNode)
            {
                if ((pNode->FindParentSpread() == StartSpread) && 
                    (pNode->GetRuntimeClass() == CC_RUNTIME_CLASS(NodePath)) /*&&
                    (pNode != OriginalPath)*/ )
                {
                    Path* ThisPath = &(((NodePath*)pNode)->InkPath);
                    INT32 ThisNum = ThisPath->GetNumCoords();
                    SubIndex = 0;
                    SubEnd = 0;
                    while (SubIndex<ThisNum)        
                    {
                        DocCoord tempStart,tempEnd;
                        ThisPath->SetPathPosition(SubIndex);    // Set the path's internal pos index
                        if (ThisPath->GetSubPathEnds(&tempStart, &tempEnd))
                        {
                            SubEnd = ThisPath->GetPathPosition();
                            // Now SubIndex is the index of the first, and SubEnd is the index
                            // of the last element (N.B. might be a curveto, in which case add 2)
                            if (ThisPath->GetVerb() == PT_BEZIERTO)
                                SubEnd+=2;

                            BOOL ClosedPath = (ThisPath->GetVerbArray()[SubEnd] & PT_CLOSEFIGURE) ;

                            // Now compare start and end with pointer position, but not if this
                            // subpath is the currently dragging subpath
                            if ( !ClosedPath &&
                                 ( (pNode != OriginalPath) ||
                                   ((pNode == OriginalPath) && (DragPoint != SubIndex) && (DragPoint != SubEnd)) ) )
                            {
                                if (PointerBlobRect.ContainsCoord(tempStart))
                                {
                                    break;
                                }
                                if (PointerBlobRect.ContainsCoord(tempEnd))
                                {
                                    SubIndex = SubEnd;
                                    break;
                                }
                            }
                        }
                        else
                        {
                            SubEnd = ThisPath->GetPathPosition();
                        }
                        SubIndex = SubEnd+1;        // Points at start of next subpath
                                                    // or top of whole path
                    }
                    // if SubIndex < ThisNum we must have found a matching coord
                    // so that's what we'll snap to
                    if (SubIndex < ThisNum)
                        break;              // Exit the outer while condition
                }
                pNode = Selected->FindNext(pNode);
            }
            // At this point, if pNode == NULL we haven't snapped to anything
            // otherwise pNode is the path we've snapped to, and SubIndex is the index
            // of the point we've snapped to
            if (pNode)
            {
                // if the snap to path is the path being edited check that it has the same number of points!
                if (((NodePath*)pNode == OriginalPath) && (OriginalPath->InkPath.GetNumCoords() != EditPath.GetNumCoords()))
                {
//                  PATRACE( _T("Attempted to join an edited path!\n"));
                    // The problem is that if the OriginalPath has been edited by adding an endpoint then
                    // SnapToIndex will be wrong as it counted along the original path, not the edited one....
                }
                else
                {
                    SnapToAnother = TRUE;
                    SnapToPath = (NodePath*)pNode;
                    SnapToIndex = SubIndex;
                    SnapToPath->InkPath.SetPathPosition(SnapToIndex);
                    PointerPos.x = SnapToPath->InkPath.GetCoord().x + LastMousePos.x - Coords[DragPoint].x;
                    PointerPos.y = SnapToPath->InkPath.GetCoord().y + LastMousePos.y - Coords[DragPoint].y;
                }
            }
        }

        // We don't allow closed paths consiting of two straight segments
        if (EndSnapped && NumCoords < 4)
            EndSnapped = FALSE;
            
        if ((EndSnapped || SnapToAnother) && (pMoveCursor != NULL))
            ChangeCursor(pCloseCursor);
        else
            ChangeCursor(pCrossHairCursor);
        
        // Now constrain the mouse point
        ERROR3IF(ConstrainPoint == DocCoord(-1,-1),"ConstrainPoint wasn't set");
        ERROR3IF(ConstrainPrevPoint == DocCoord(-1,-1),"ConstrainPrevPoint wasn't set");
        ERROR3IF(ConstrainNextPoint == DocCoord(-1,-1),"ConstrainNextPoint wasn't set");
        if (!EndSnapped && ClickMods.Constrain)
        {
            if (ClickMods.Adjust)
            {
                if (ClickMods.Alternative1 || ClickMods.Alternative2)
                    DocView::ConstrainToAngle(ConstrainNextPoint, &PointerPos);
                else
                    DocView::ConstrainToAngle(ConstrainPrevPoint, &PointerPos);
            }
            else
                DocView::ConstrainToAngle(ConstrainPoint, &PointerPos);
        }

        // Only snap to grid if we didn't snap to the end of a path
        if (!EndSnapped)
            DocView::SnapCurrent(StartSpread,&PointerPos);

        // This is the bit where we go off and re-calculate the paths position,
        // based on how much the mouse has moved
        DocCoord Offset;
        Offset.x = PointerPos.x - LastMousePos.x;
        Offset.y = PointerPos.y - LastMousePos.y;

        RecalculatePath(Offset, EndSnapped, DragPoint);

        if (EditObjChange.ChangeMask.EorBlobs)
        {
            ChangeCode Chge = EditObjChange.RenderChangedBlobs(OriginalPath,this,&EditPath,StartSpread,TRUE);
            if (Chge!=CC_OK)
            {
                // replace the old edit path
                EditPath.CopyPathDataFrom(&TempPath);
                RenderPathEditBlobs( EditPath.GetBoundingRect(), StartSpread );
                return;
            }
        }

        // Update the Last Mouse Position
        LastMousePos = PointerPos;

        // Draw in the new version of the path
        RenderPathEditBlobs( EditPath.GetBoundingRect(), StartSpread );

        // If there is just one selected point being dragged then we should show
        // its new position in the line tool infobar.
        if (UpdatePoint != -1)
            BROADCAST_TO_ALL(PathEditedMsg(&EditPath, pSpread, UpdatePoint));

        SetStatusLineHelp();
    }
    else
    {   
        NodeListItem* pCurrentOrig = (NodeListItem*) OriginalPaths.GetHead ();
        NodeListItem* pCurrentEdit = (NodeListItem*) EditPaths.GetHead ();
        NodeListItem* pCurrentChange = (NodeListItem*) ObjChanges.GetHead ();
        NodeListItem* pCurrentDragS = (NodeListItem*) PathsDragStarted.GetHead ();

        DocCoord Offset(0,0);

        while ((pCurrentOrig) && (pCurrentEdit) && (pCurrentChange) && (pCurrentDragS))
        {
            NodePath* pOrigPath = (NodePath*) (pCurrentOrig->pNode);
            Path* pEditPath = (Path*) (pCurrentEdit->pNode);
            ObjChangePathEdit* pObjChange = (ObjChangePathEdit*) (pCurrentChange->pNode);
            BOOL* pDragStarted = (BOOL*) (pCurrentDragS->pNode);


            // If drag has moved onto a different spread, convert the coord to be relative to the
            // original spread.
            if (pSpread != StartSpread)
                PointerPos = MakeRelativeToSpread(StartSpread, pSpread, PointerPos);

            Path TempPath;

            // inform the parent a change is happening
            if (pObjChange->ChangeMask.EorBlobs)
            {
                ChangeCode Chge = pObjChange->RenderCurrentBlobs(pOrigPath,this,pEditPath,StartSpread,TRUE);
                if (Chge!=CC_OK)
                    return;
                // Create a local copy of the edit path
                if (!TempPath.Initialise(pEditPath->GetNumCoords(), 12))
                    return;
                TempPath.CopyPathDataFrom(pEditPath);
            }

            // Rub out the old EORed version of the path
            if (*pDragStarted == TRUE)
            {
                RenderPathEditBlobs(pEditPath, /*pEditPath->GetBoundingRect(),*/ StartSpread );
            }
            else
            {
                *pDragStarted = TRUE;
//              pCurrentDragS->pNode = (Node*) pDragStarted;
            }

            DocRect PointerBlobRect;
            GetApplication()->GetBlobManager()->GetBlobRect(PointerPos,&PointerBlobRect);

            DocCoord* Coords = pEditPath->GetCoordArray();
//          PathFlags* Flags = pEditPath->GetFlagArray();
            PathVerb* Verbs = pEditPath->GetVerbArray();
            INT32 NumCoords = pEditPath->GetNumCoords();

            if (pCurrentOrig == (NodeListItem*) OriginalPaths.GetHead ())
            {
                // CGS:  all of the operations to do with snapping to grid, snapping to opposite
                // end point and snapping to another lines endpoint are relevant only for
                // that control point that the drag was initiated from ....

                // Here is where we do all the snapping to grids and endpoints
                // and constrain. First we check for snapping to line ends, then
                // we check constrain, then we check grid snapping

                EndSnapped = FALSE;         // TRUE if this point snaps to the other end
                SnapToAnother = FALSE;      // TRUE if this point snaps to another line end
                SnapToLineOrCurve = FALSE;  // No snapped other line

                // We might be snapping to an endpoint if the point we're dragging around is either
                // a moveto, or is the last point in the subpath. We will also only snap if there is
                // only one point selected on the path

                INT32 i;
                if (DragPoint != -1)
                {
                    // Look to see if the selected point is a real endpoint
                    if (Verbs[DragPoint] == PT_MOVETO)
                    {
                        // This is the start element of the path
                        i = DragPoint;
                        if (!pEditPath->IsSubPathClosed(i))
                        {
                            INT32 NextEndpoint = i;
                            if (pEditPath->FindNextEndPoint(&NextEndpoint))
                            {
                                pEditPath->FindEndElOfSubPath(&i);      // i indexes to the end element

                                // If this sub-path is one element long then closing it is not allowed
                                if ((i != NextEndpoint) && PointerBlobRect.ContainsCoord(Coords[i]))
                                {
                                    PointerPos.x = Coords[i].x + LastMousePos.x - Coords[DragPoint].x;
                                    PointerPos.y = Coords[i].y + LastMousePos.y - Coords[DragPoint].y;
                                    EndSnapped = TRUE;
                                }
                            }
                        }
                    }
                    else if (DragPoint+1 == NumCoords || Verbs[DragPoint+1] == PT_MOVETO)
                    {
                        // This is the last element in the sub-path
                        i = DragPoint;
                        if (!pEditPath->IsSubPathClosed(i))
                        {
                            INT32 PrevEndpoint = i;
                            if (pEditPath->FindPrevEndPoint(&PrevEndpoint))
                            {
                                pEditPath->FindStartOfSubPath(&i);          // i is the index of the start of the sub-path
                    
                                // If this sub-path is one element long then closing it is not allowed
                                if ((i != PrevEndpoint) && PointerBlobRect.ContainsCoord(Coords[i]))
                                {
                                    PointerPos.x = Coords[i].x + LastMousePos.x - Coords[DragPoint].x;
                                    PointerPos.y = Coords[i].y + LastMousePos.y - Coords[DragPoint].y;
                                    EndSnapped = TRUE;
                                }
                            }
                        }
                    }
                }
            
                // That detects snapping to the opposite endpoint, but what about snapping to another
                // endpoint altogether? Time to check for that eventuality
                if (!EndSnapped && DragPoint != -1 && (Verbs[DragPoint] == PT_MOVETO || DragPoint+1 == NumCoords || Verbs[DragPoint+1] == PT_MOVETO) )
                {
                    // Get a snapshot of the selection
                    SelRange* Selected = GetApplication()->FindSelection();

                    // do something extra in here ....

                    Node* pNode = Selected->FindFirst();
                    INT32 SubIndex,SubEnd;
                    while (pNode)
                    {
                        if ((pNode->FindParentSpread() == StartSpread) && 
                            (pNode->GetRuntimeClass() == CC_RUNTIME_CLASS(NodePath)) /*&&
                    (pNode != OriginalPath)*/ )
                        {
                            Path* ThisPath = &(((NodePath*)pNode)->InkPath);
                            INT32 ThisNum = ThisPath->GetNumCoords();
                            SubIndex = 0;
                            SubEnd = 0;
                            while (SubIndex<ThisNum)        
                            {
                                DocCoord tempStart,tempEnd;
                                ThisPath->SetPathPosition(SubIndex);    // Set the path's internal pos index
                                if (ThisPath->GetSubPathEnds(&tempStart, &tempEnd))
                                {
                                    SubEnd = ThisPath->GetPathPosition();
                                    // Now SubIndex is the index of the first, and SubEnd is the index
                                    // of the last element (N.B. might be a curveto, in which case add 2)
                                    if (ThisPath->GetVerb() == PT_BEZIERTO)
                                        SubEnd+=2;

                                    BOOL ClosedPath = (ThisPath->GetVerbArray()[SubEnd] & PT_CLOSEFIGURE) ;

                                    // Now compare start and end with pointer position, but not if this
                                    // subpath is the currently dragging subpath
                                    if ( !ClosedPath &&
                                         ( (pNode != OriginalPath) ||
                                           ((pNode == OriginalPath) && (DragPoint != SubIndex) && (DragPoint != SubEnd)) ) )
                                    {
                                        if (PointerBlobRect.ContainsCoord(tempStart))
                                        {
                                            break;
                                        }
                                        if (PointerBlobRect.ContainsCoord(tempEnd))
                                        {
                                            SubIndex = SubEnd;
                                            break;
                                        }
                                    }
                                }
                                else
                                {
                                    SubEnd = ThisPath->GetPathPosition();
                                }
                                SubIndex = SubEnd+1;        // Points at start of next subpath
                                                            // or top of whole path
                            }
                            // if SubIndex < ThisNum we must have found a matching coord
                            // so that's what we'll snap to
                            if (SubIndex < ThisNum)
                                break;              // Exit the outer while condition
                        }
                        pNode = Selected->FindNext(pNode);
                    }
                    // At this point, if pNode == NULL we haven't snapped to anything
                    // otherwise pNode is the path we've snapped to, and SubIndex is the index
                    // of the point we've snapped to
                    if (pNode)
                    {
                        // if the snap to path is the path being edited check that it has the same number of points!
                        if (((NodePath*)pNode == pOrigPath) && (pOrigPath->InkPath.GetNumCoords() != pEditPath->GetNumCoords()))
                        {
//                          PATRACE( _T("Attempted to join an edited path!\n"));
                            // The problem is that if the OriginalPath has been edited by adding an endpoint then
                            // SnapToIndex will be wrong as it counted along the original path, not the edited one....
                        }
                        else
                        {
                            SnapToAnother = TRUE;
                            SnapToPath = (NodePath*)pNode;
                            SnapToIndex = SubIndex;
                            SnapToPath->InkPath.SetPathPosition(SnapToIndex);
                            PointerPos.x = SnapToPath->InkPath.GetCoord().x + LastMousePos.x - Coords[DragPoint].x;
                            PointerPos.y = SnapToPath->InkPath.GetCoord().