Representation of SCTN Ends

Note: The functionality described in this section will be removed at a future release of Draft.

The DRGP (Drawing Priority) SCTN attribute is used by Draft to determine how to draw SCTN ends in hidden-lines-removed views. DRGP may be set (in the Design Database) to any integer value between 0 (highest priority) and 50.

The effect is demonstrated in the diagrams below, which show plan views of four SCTNs meeting at a node point. The top flanges of the SCTNs are coplanar and none of the SCTN ends have been cut back. In Figure 16:1 below (a) the DRGP attributes of all four SCTNs have been left at 0; as a result Draft is unable to determine how to draw the intersection lines between the SCTNs and so draws the full outlines of all SCTNs. In Figure 16:1 (b) the DRGP attributes of the four SCTNs have been set as indicated, which confers a priority order on them. As a result, Draft is able to determine the representation that is intended.

Figure 16:1. Effect of SCTN DRGP Attribute

Users should be aware that using this functionality in non-orthogonal Views may produce slightly distorted results. This is because when producing the graphics the SCTNs are 'shifted' slightly in the View direction by an amount relative to the SCTN's DRGP value to allow the hidden-line-removal code to function. Distortion is especially likely to be noticed if large values of DRGP are used. We would recommend that DRGP values are kept as small as possible and preferably less than 10.