private void RemoveAdorner(ref DrawBondAdorner adorner)
{
var layer = AdornerLayer.GetAdornerLayer(CurrentEditor);
layer.Remove(adorner);
adorner = null;
}
///
/// what happens when we move the mouse
///
private void CurrentEditor_PreviewMouseMove(object sender, MouseEventArgs e)
{
Bond existingBond = null;
if (_adorner != null)
{
RemoveAdorner(ref _adorner);
}
var targetedVisual = CurrentEditor.ActiveVisual;
string bondOrder = EditViewModel.CurrentBondOrder;
//check to see if we have already got an atom remembered
if (_currentAtomVisual != null)
{
Point?lastPos;
if (Dragging(e))
{
CurrentStatus = "[Shift] = unlock length; [Ctrl] = unlock angle; [Esc] = cancel.";
//are we already on top of an atom?
if (targetedVisual is GroupVisual gv)
{
CurrentEditor.Cursor = Cursors.No;
lastPos = null;
}
else if (targetedVisual is AtomVisual atomUnderCursor)
{
CurrentEditor.Cursor = CursorUtils.Pencil;
//if so. snap to the atom's position
lastPos = atomUnderCursor.Position;
//if we are stroking over an existing bond
//then draw a double bond adorner
existingBond = _lastAtomVisual.ParentAtom.BondBetween(atomUnderCursor.ParentAtom);
if (_lastAtomVisual != null &&
existingBond != null)
{
if (existingBond.Order == OrderSingle)
{
bondOrder = OrderDouble;
}
else if (existingBond.Order == OrderDouble)
{
bondOrder = OrderTriple;
}
else if (existingBond.Order == OrderTriple)
{
bondOrder = OrderSingle;
}
}
}
else //or dangling over free space?
{
CurrentEditor.Cursor = CursorUtils.Pencil;
lastPos = e.GetPosition(CurrentEditor);
var angleBetween =
Vector.AngleBetween(_lastAtomVisual?.ParentAtom?.BalancingVector() ?? BasicGeometry.ScreenNorth,
BasicGeometry.ScreenNorth);
//snap a bond into position
lastPos = _angleSnapper.SnapBond(lastPos.Value, e, angleBetween);
}
if (lastPos != null)
{
_adorner = new DrawBondAdorner(CurrentEditor, BondThickness)
{
Stereo = EditViewModel.CurrentStereo,
BondOrder = bondOrder,
ExistingBond = existingBond
};
_adorner.StartPoint = _currentAtomVisual.Position;
_adorner.EndPoint = lastPos.Value;
}
}
}
else
{
if (targetedVisual is GroupVisual gv) //can't draw on a group
{
CurrentStatus = "Ungroup before attempting to draw.";
CurrentEditor.Cursor = Cursors.No;
}
else if (targetedVisual is AtomVisual av)
{
CurrentEditor.Cursor = CursorUtils.Pencil;
if (EditViewModel.SelectedElement != av.ParentAtom.Element)
{
CurrentStatus = "Click to set element.";
}
else
{
CurrentStatus = "Click to sprout chain";
}
}
else if (targetedVisual is BondVisual bv)
{
CurrentEditor.Cursor = CursorUtils.Pencil;
CurrentStatus = "Click to modify bond";
}
}
}
