Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!zaphod.mps.ohio-state.edu!mips!bridge2!3comvax!tymix!tardis!jms
From: jms@tardis.Tymnet.COM (Joe Smith)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: (Non) Square Pixels?
Message-ID: <943@tardis.Tymnet.COM>
Date: 23 Feb 90 10:25:52 GMT
References: <4687@lmrc.uucp> <3119@cello.UUCP>
Reply-To: jms@tardis.Tymnet.COM (Joe Smith)
Organization: BT Tymnet, San Jose, CA
Lines: 37

To: cs.utexas.edu!romp!auschs!cello!sabre!robin
Subject: Re: (Non) Square Pixels?
Newsgroups: comp.sys.amiga.hardware
In-Reply-To: <3119@cello.UUCP>
References: <4687@lmrc.uucp>
Organization: BT Tymnet, San Jose, CA

In article <3119@cello.UUCP> you write:
>The machine doesn't control the shape of the pixel.  It merely sends the signal
>to the montior to GENERATE the pixels.  Only the monitor controls how they are
>shaped.  

The topic being discussed is not round versus square pixels, but rather
rectangular versus square pixels.

The machine DOES control the shape of the pixels.  A 640x200 screen tall,
skinny pixels.  A 320x400 screen has short, fat pixels.  A 640x400 screen
has small, almost square pixels.  A 320x200 screen has big, fat pixels, and
each pixel consists of several glowing phosphor dots.  This is true for all
monitors.  The shape of the dots of phosphor and the number of phosphor dots
per square inch do not really affect the shape of the pixels.  The thing
that affects the shape of the pixels the most are:

	1) the vertical distance the beam travels
	2) the horizontal distance the beam travels
	3) interlace versus non-interlace
	4) the color clock frequency (7.16 versus 14.3 MHz)

Items 1 and 2 can be adjusted at the monitor.  Items 3 and 4 are under
control of the CPU.  Amiga monitors can be forced to display square
pixels by reducing the vertical height, at which point the monitor is
displaying more horizontal lines than a typical TV set.
-- 
Joe Smith (408)922-6220 | SMTP: jms@tardis.tymnet.com or jms@gemini.tymnet.com
BT Tymnet Tech Services | UUCP: ...!{ames,pyramid}!oliveb!tymix!tardis!jms
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