Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Ed Federmeyer <fedeedw@charlie.cns.iit.edu>
Newsgroups: scea.yaroze.programming.3d_graphics
Subject: Hither clipping plane
Date: Sun, 13 Jul 1997 19:14:40 -0500
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I've been working with objects in 3D space lately, and I'm having
a hard time controlling when objects are too close to the display
screen, and "dissapear".

Basically, it looks like the "hither clipping plane" (the close
Z-axis clipping plane) is too far "into" the screen.

I have objects that move around on the X-Z (horizontal) plane, with my
viewpoint looking down at a slight angle onto a playfield that extends
well beyond the borders of the screen.

As the objects start heading in the -Z direction (they get closer to
the viewpoint), they should appear to go "under" the viewpoint smoothly
and dissapear only when they are completely out of the view.

Instead, they completely pop-out before they even start "going under"
the viewpoint.

I can get the effect I want by making my viewpoint look more straight
down on the playfield, but I really want a shallower, 3/4 style
point-of-view.

Is there a function for setting hither-and-yon clipping behavior of
the 3D graphics routines?

Messing with the projection distance helped a *little*, but the view
get *very* distorted very quickly.

Any tips or suggestions are welcome!
Ed Federmeyer