View Limits

The VIEW element attribute controlling whether the View limits are locked to the view frame is VFLIIND ('View Frame Limits Independent'). The default is TRUE, in common with historic VIEW behavior. Setting the attribute to FALSE unlocks the frame from the view limits (attribute VWLIMITS) so they can be manipulated independently. To avoid confusion, note that the sense of the VFLIIND attribute is the reverse of the view property "Limits locked to frame" in the user interface (ie "Limits locked to frame" false is implied by VFLIIND TRUE and vice-versa).

The VWLIMITS physical attribute on the VIEW can be set manually using the following example syntax:

Vwlimits From E 1500mm S 2001mm U 1285mm To E 15465mm N 18500mm U 23962mm

Note:
The VWLIMITS attribute is ignored if VFLIIND is FALSE as the view limits are then calculated from the view frame. If VFLIIND is TRUE.

The VWLIMITS attribute should not be confused with the read-only VLIMITS pseudo attribute.

Q VLIMITS

returns the 3d coordinates corresponding to the view frame (and 0 perpendicular to the plane of the paper).

When a view frame is larger than the view limits, the expected behavior is for all Model elements within or overlapping the limits box to displayed in their entirety (up to the view frame and of course only as determined by the view's Idlist). Model elements entirely outside the view limits will not be displayed. If the user requires Model elements that overlap the view limits to be clipped to the view limits it is necessary to apply clipping planes, as is normal to achieve any clipping inside the view frame.