// start selection/resizing/moving
protected override void OnMouseDown(MouseEventArgs e)
{
base.OnMouseDown(e);
if (IsSelectionAreaPresent()) // we have selected area
{
if (!selectionArea.Contains(e.Location))
{ // we are outside of selected => erase current selection
selectionArea = new Rectangle(0, 0, 0, 0);
Invalidate();
croppingState = CroppingState.NONE;
return;
}
else // we are within the selection area
{
DragCorner dc = PointAtDragCorner(selectionArea, e.Location);
if (dc != DragCorner.NONE)
{ // we are at a corner of selection => we start resizing
croppingState = CroppingState.RESIZING; // it is a special drag, where the corners are pulled for resizing
dragPreviousPoint = e.Location; // initial previous drag location
}
else
{ // we are inside selection => we start dragging
croppingState = CroppingState.DRAGGING;
dragPreviousPoint = e.Location; // initial previous drag location
}
}
}
else // we just start selecting
{
croppingState = CroppingState.SELECTING;
selectionStartPoint = e.Location; // initial selection area location
}
}
private void clearSelectionArea()
{
selectionArea = new Rectangle(0, 0, 0, 0);
Invalidate();
croppingState = CroppingState.NONE;
}
protected override void OnMouseUp(MouseEventArgs e)
{
base.OnMouseUp(e);
croppingState = CroppingState.NONE;
}
