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From: tjh@bucrf11.bu.edu (Tim Hall)
Newsgroups: comp.sys.sgi
Subject: reading overlay planes on non-PI machines
Message-ID: <1990Oct9.180347@bucrf11.bu.edu>
Date: 9 Oct 90 22:03:47 GMT
Sender: news@bu.edu.bu.edu
Reply-To: tjh@bucrf11.bu.edu (Tim Hall)
Followup-To: comp.sys.sgi
Organization: Boston University Computer Graphics Lab
Lines: 23

Is it possible to read the overlay/underlay planes on non-PI machines?
I dug through the manuals (honest!) and I didn't come up with anything.
There is, of course, readsource( SRC_OVER ) and then doing a rectread
but the man page for readsource claims that the flag SRC_OVER only works
on PI's.  We'd like to do it on a 4D/2xx machines too.

If I recall correctly, gl_readscreen is able to read the overlay planes
on non-PI's but returns RGB values, not the color map values.

While I'm here, just a check.  The following would...
	overlay( 4 );
	readsource( SRC_OVER );
	rectread( blah, blah, woof, woof, buf );
...return 4 bits/pixel in the short array buf.

Many thanks for any help.

--
-Tim Hall
tjh@bu-pub.bu.edu

The night is filled with the cries of dispossessed children in search
of paradise.  -Dead Can Dance