🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: comp.sys.sgi.graphics
Article #154

Re: Problems with blink() (Help!)

#154
From: Brett Bainter
Date: Thu, 28 Jan 1993 03:02
32 lines
1926 bytes
In article <C0GCo0.9C7@cmcl2.nyu.edu>, dario@cns.nyu.edu (Dario Ringach, x3941) writes:
|> I've been having problems making blink() work on a Crimson running IRIX
|> Release 4.0.5 System V.  The problem is that blinking works, but it
|> blinks the color in the colormap with BLACK always, independently of
|> the red, green, blue, entries in:  blink(rate,index,red,green,blue).
|> 
|> Does anyone know why?  Thanks in advance for any help.


this is due to a known bug with blink().  it is passing the rgb values
directly to x.  since x's rgb range is 0..65535 the normal gl rgb values
of 0..255 really are close to black.  the problem can be worked around
by shifting your colors up 8 bits (which is what the fix will do internally).

you can use the following macro to help:

#define m_blink(rate,index,r,g,b)  blink(rate, index, (r)<<8, (g)<<8, (b)<<8)

some other things to look out for when using blink:

1. make sure you gflush your mapcolors. (the blinker.c example from 4Dgifts
   has a problem in that it does not do this).

2. there is a known bug where blinking will fail if a program exits and
   leaves blinking on.  thus you should always do a blink(-1, 0, 0, 0)
   before exiting.  another methodology is to turn blinking on when you
   get focus and turn it off when you lose focus.

-- 
Brett Bainter
Silicon Graphics
brettb@sgi.com
Technical Details
Message-ID: <1993Jan28.030206.14026@odin.corp.sgi.com>
Path: arc1-ca.pugleaf.net!sparky!uunet!charon.amdahl.com!amdahl!rtech!pacbell.com!ames!elroy.jpl.nasa.gov!sdd.hp.com!sgiblab!sgigate!odin!batcave.csd.sgi.com!brettb
References: <C0GCo0.9C7@cmcl2.nyu.edu>

Show Full Headers
Complete Article Headers
Newsgroups: comp.sys.sgi.graphics
Path: arc1-ca.pugleaf.net!sparky!uunet!charon.amdahl.com!amdahl!rtech!pacbell.com!ames!elroy.jpl.nasa.gov!sdd.hp.com!sgiblab!sgigate!odin!batcave.csd.sgi.com!brettb
From: brettb@batcave.csd.sgi.com (Brett Bainter)
Subject: Re: Problems with blink()  (Help!)
Message-ID: <1993Jan28.030206.14026@odin.corp.sgi.com>
Sender: news@odin.corp.sgi.com (Net News)
Nntp-Posting-Host: batcave.csd.sgi.com
Organization: Silicon Graphics, Inc.
References:  <C0GCo0.9C7@cmcl2.nyu.edu>
Date: Thu, 28 Jan 1993 03:02:06 GMT
Lines: 32