Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!wdl1!sgi!msc
From: msc@ramoth.SGI.COM (Mark Callow)
Newsgroups: comp.windows.misc
Subject: Re: simple (dumb?) question
Message-ID: <11747@sgi.SGI.COM>
Date: 26 Feb 88 19:07:24 GMT
References: <3132@bloom-beacon.MIT.EDU>
Sender: daemon@sgi.SGI.COM
Lines: 21
Summary: implementors aren't dumb

In article <3132@bloom-beacon.MIT.EDU>, tada@athena.mit.edu (Michael Zehr) writes:
> 
> ... However, I've yet to see
> routines like draw_vertical_line, draw_horizontal_line,
> draw_rectangle, etc.  With lines, usually a fair number of them are
> drawn either horizontally or vertically.  Are the draw_line routines
> implemented so efficiently that there wouldn't be much of a speed
> savings by special-casing h. and v. lines?  Or is the current design
> philosophy to avoid special cases as much as possible?  

Usually the implementors special case horizontal and vertical lines inside
the draw-line primitive to save you the trouble.

The implementors of the primitives typically know better than the user what
should be treated as a special case on a given machine especially when
dealing with hardware assists.
--
From the TARDIS of Mark Callow
msc@sgi.sgi.com, ...{ames,decwrl,sun}!sgi!msc
"There is much virtue in a window.  It is to a human being as a frame is to
a painting, as a proscenium to a play.  It strongly defines its content."