By default the bitmap graph of the model is scaled to ensure that the entire model will fit inside the Graph Window, independent of the view direction. By using Zoom In and Zoom Out the size of the current graph can be increased or decreased. Note that the
complete bitmap is re-sized — the rest of the graph can be seen by clicking
on the scroll bars. This implies that too much zooming can cause the graph to
become extremely large requiring a very large memory capacity. Zoom Out
tries to keep the centre of the Graph Window in the centre of the entire graph. Once the graph is of the same size as the Graph Window it will not be decreased further, but the scale will be increased such that a larger part of the model will appear inside the graph. Zoom Full resets the default graph scaling condition as well as the default view radius.