VARKON Version 1.15 1997-10-24

perp_view - Procedure

Sets perspective


Description

Changes the viewing distance for named view. Viewing distance is used to create true 3D perspective projections. A viewing distance of zero turns true perspective off and switches to parallel projection. This is also the default when a new view is created

Syntax

perp_view(name, dist)

STRING	name*15;
FLOAT	dist;

Principal parameters

name	- The name of the view
dist	- The new viewing distance

Optional parameters

None.

Comments

Viewing distance is measured as the true distance between the observer and X=Y=Z=0 in the view coordinate system. It is therefore important to assure that the distance is large enough to place the observer well outside the model. A viewing distance smaller than the size of the model would mean entering into the model and looking at it from the inside out. Currently VARKON does not support that.

In order to display the model with respect to the new viewing distance use rep_view() with appropriate parameters. perp_view() does not update the display automatically.