Subject: Preview of next release...

From: Dave Stampe-Psy+Eng <dstamp@watserv1>
Date: Sat, 21 Mar 92 21:58:27 -0500

I found some time this weekend to work on REND386, and have
gotten the 256 color stuff going.  Most of the work was in
retrofitting the user-interface stuff.

The speed decrement in going from 16 to 256 colors is not as
bad as expected: 15-polygon worlds have a 20% speed loss, and
500-polygon worlds have a 12% speed loss.  So it dropped from
16 fps to 14 fps testing with bishban.plg.

The 256-color stuff can be used in cosine-lit and unlit modes
simultaneously.  Each color word for the polygons has a hue
and brightness field-- if you specify the hue as zero, the 
brightness field specifies the DAC entry to use.  If the hue
is from 1 to 15, that "base color" is used (with the brightness
field specifying the reflectivity of the polygon) with the cosine 
light source.  There are 16 levels (plus black) of brightness per
hue.

The cosine-lighting actually looks a bit dissapointing in color,
mainly because of the few (16) levels of brightness available.
This allows interaction between the colors of adjacent polygons,
causing apparent hue shifts.  The unlit stuff does not look as
3 dimensional (looks a lot like a velvet or flourescent surface)
but altogether it's not bad.  Don't think it's worth going to
7 hues with 32 brightnesses, however.

Got the mouse-select in the demo debugged finally (OK for selecting
and testing).  Selected objects are wireframed over the polys (neat
effect).  Still have to decide on the exact object-motion interface
and do some sort of demo on structured motion.

Any suggestions while the hood's up?

- Dave Stampe

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From: Chris Hand <[email-masked]>
Date: 23 Mar 92 11:30

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==================
> Any suggestions while the hood's up?

What resolutions does the new version support?  Does it include
the "tweaked VGA" 360x480x256 as used in fractint?  I suppose this
uses too much RAM to be double-buffered?

What about SEGA LCD glasses support? (not that I even know anywhere
that sells them here in the UK...).

Is there an OFF-->PLG converter floating around anywhere?  If not
I will knock one up in the next couple of weeks, time permitting.
Even better, how much hassle would it be to allow the REND386
code (or demo or W.H.Y) to read OFF files directly?

Cheers,

Chris

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From: Bernie Roehl <broehl>
Date: Mon, 23 Mar 92 9:15:40 EST

> What resolutions does the new version support?

320x200x16 and 320x200x256

> What about SEGA LCD glasses support?

Relatively easy to add, and can be added in the user's application code
(i.e. does not need to be part of the library).  Simply render the left
and right eye images to different pages, then arrange to switch pages (and
LCD shutters) every so often (probably under interrupts).

> Is there an OFF-->PLG converter floating around anywhere?

I was working on one, and hope to get back to it this week (maybe in time
for our next release).  Bear in mind that most OFF files have far too many
points in them to be practical for real-time work.

> code (or demo or W.H.Y) to read OFF files directly?

Not hard, and again something that could be done in the application program
without modifying the library at all.

-- 
	Bernie Roehl, University of Waterloo Electrical Engineering Dept
	Mail: [email-masked] OR [email-masked]
	BangPath: uunet!watmath!sunee!broehl
	Voice:  (519) 885-1211 x 2607 [work]

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From: Dave Stampe-Psy+Eng <dstamp@watserv1>
Date: Mon, 23 Mar 92 10:04:55 -0500

The REND386 code has always had mechanisms (user-definable functions)
to set your own resolution, colors, drawing routines, etc.  No one 
seems to be using them, though!  All I did for the 256-color mode
was clean up some of the user-interface code and write some new 
color-setting and drawing-interface code.  No assembly required!

In the case of 320x400, it just requires that you write your own
mode-setting routine, set the clipping window, and either write your
own page-setting routine or use only even pages.  Go to it.

Sega glasses:  I'm thinking of posting a small test program I've
written that tests for VGA vertical interrupts, as well as speed.
This would give us some idea whether to go with interrupt or timer-driven 
methods.  Again, you can easily write your own code (set_vpage() affects
nothing else, so you can call it from interrupts).

In conclusion: REND386 is flexible, so you're responsible for your
own customizations.  If you need help-- well, that's what this
mail-list is for!

- Dave Stampe