From: C.G.C.vanDijk@io.tudelft.nl
Newsgroups: comp.sys.sgi
Subject: anti-aliasing, perfly, reality-engine: question
Date: 15 Oct 92 21:03:51 GMT

A question concerning reality engine, perfly, and antialiasing:

Two weeks ago, we got our Reality Engine update for out Crimson/VGX,
one-span cheapest flavor ;-).  Some of the new demos are really
amazing stuff: you could drop of your chair if you get too absorbed
in the fly-thru-landscape demo's.  Great textures.  But..

Anti-aliasing does not seem to work on this one-span Crimson/RE.

Who knows what is going on?  Did I miss the fine print that says that
a Reality Engine is a great machine for anti-aliased textures as long
as you buy a 2 or 4 span version?  (Hey, we ordered this thing when it
was still called Venice; we did not even have all the normal print.)

I found out the following:

- We did not get any hardcopy documentation with our Crimson/RE, and
  the on-line documentation did not tell me enough.  Should I order
  the m4-glgt-4.0.1-graphics manuals?
- The perfly demo that I saw on another Crimson/RE had a button called
  'anti-aliasing'.  When on, everything looks great.  When off, all the
  lines go flickering, just as one would expect from aliasing.
  Our demo does _not_ have this button (consequently the demo is aliased).
  Can anyone tell me why not? Does this program do a getgdesc() call to
  test if there is anti-aliasing available?  (I added my gdesc & hinv below).
- Our wireframe f-15 demo features line drawing anti-aliasing, seemingly
  at normal speed (but a Crimson would do this at normal speed even in
  software?!)
- Our Inventor SceneViewer application features an anti-aliasing menu
  option.  When chosen, redraw time goes to several seconds and the CPU
  sighs heavily, suggestion software anti-aliasing.
- In the release notes it says that we can have multisample AA 'even
  on the base configuration' RE if you setmon -x SmallWindow_60.  If your
  monitor can handle it of course; mine goes beserk.  This small note
  really scares me.  Does something like 'singlesample' AA exist?
- SGI Holland probably filed my questions on this subject on to mountain
  view, because they did not get back to me in two weeks.  They are usually
  very pleasant, open and quick with their reactions.

Please somebody tell me that I just have to press a dipswitch on the
RE board or something, and that we did not buy too cheap a machine..

Cheers,
                       Casper

ir. Casper G.C. van Dijk
Delft University of Technology
Faculty of Industrial Design Engineering
Section Engineering Design
P.O. Box 5029, 2600 GA  Delft, the Netherlands
Phone: +31 15 783788
Fax: +31 15 787316
E-mail: C.G.C.vanDijk@IO.TUDelft.NL

PS: my hinv & all my getgdesc's:

1 50 MHZ IP17 Processor
FPU: MIPS R4010 Floating Point Chip Revision: 0.0
CPU: MIPS R4000 Processor Chip Revision: 2.2
On-board serial ports: 4
Data cache size: 8 Kbytes
Instruction cache size: 8 Kbytes
Secondary unified instruction/data cache size: 1 Mbyte
Main memory size: 64 Mbytes
I/O board, slot F: IO3B
Integral Ethernet: et0, IO3
RealityEngine Graphics option installed
Integral SCSI controller 1: Version WD33C93A, revision 9
Disk drive: unit 1 on SCSI controller 0
Integral SCSI controller 0: Version WD33C93A, revision 9

 GD_XPMAX	1280 
 GD_YPMAX		1024 
 GD_XMMAX		340 
 GD_YMMAX		272 
 GD_ZMIN			-2147479552 
 GD_ZMAX			2139095040 
 GD_BITS_NORM_SNG_RED	12 
 GD_BITS_NORM_SNG_GREEN	12 
 GD_BITS_NORM_SNG_BLUE	12 
 GD_BITS_NORM_DBL_RED	12 
 GD_BITS_NORM_DBL_GREEN	12 
 GD_BITS_NORM_DBL_BLUE	12 
 GD_BITS_NORM_SNG_CMODE	12 
 GD_BITS_NORM_DBL_CMODE	12 
 GD_BITS_NORM_SNG_MMAP	8 
 GD_BITS_NORM_DBL_MMAP	8 
 GD_BITS_NORM_ZBUFFER	32 
 GD_BITS_OVER_SNG_CMODE	8 
 GD_BITS_UNDR_SNG_CMODE	8 
 GD_BITS_PUP_SNG_CMODE	2 
 GD_BITS_NORM_SNG_ALPHA	12 
 GD_BITS_NORM_DBL_ALPHA	12 
 GD_BITS_CURSOR		2 
 GD_OVERUNDER_SHARED	0 
 GD_BLEND		1 
 GD_CIFRACT		1 
 GD_CROSSHAIR_CINDEX	3 
 GD_DITHER		1 
 GD_LINESMOOTH_CMODE	1 
 GD_LINESMOOTH_RGB	1 
 GD_LOGICOP		1 
 GD_NSCRNS		1 
 GD_NURBS_ORDER		8 
 GD_NBLINKS		20 
 GD_NVERTEX_POLY		256 
 GD_PATSIZE_64		0 
 GD_PNTSMOOTH_CMODE	1 
 GD_PNTSMOOTH_RGB	1 
 GD_PUP_TO_OVERUNDER	0 
 GD_READSOURCE		1 
 GD_READSOURCE_ZBUFFER	1 
 GD_STEREO		1 
 GD_SUBPIXEL_LINE	1 
 GD_SUBPIXEL_PNT		1 
 GD_SUBPIXEL_POLY	1 
 GD_TRIMCURVE_ORDER	8 
 GD_WSYS			1 
 GD_ZDRAW_GEOM		1 
 GD_ZDRAW_PIXELS		1 
 GD_SCRNTYPE		0 
 GD_TEXTPORT		1 
 GD_NMMAPS		16 
 GD_FRAMEGRABBER		0 
 GD_TIMERHZ		67 
 GD_DBBOX		0 
 GD_AFUNCTION		1 
 GD_ALPHA_OVERUNDER	0 
 GD_BITS_ACBUF		24 
 GD_BITS_ACBUF_HW	12 
 GD_BITS_STENCIL		8 
 GD_CLIPPLANES		6 
 GD_FOGVERTEX		1 
 GD_LIGHTING_TWOSIDE	1 
 GD_POLYMODE		1 
 GD_POLYSMOOTH		1 
 GD_SCRBOX		1 
 GD_TEXTURE		1 
 GD_FOGPIXEL		1 
 GD_TEXTURE_PERSP	1 
 GD_MUXPIPES		1