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From: jimf@SABER.COM
Newsgroups: comp.windows.x
Subject: Re: XPutImage() vs XDrawPoint() performance.
Message-ID: <9007131253.AA10897@bowie>
Date: 13 Jul 90 12:53:39 GMT
Sender: daemon@athena.mit.edu (Mr Background)
Organization: The Internet
Lines: 20

|I would suggest using neither.  Use XDrawPoints, which will give you
|better network/IPC bandwidth/performance.  If you don't want to or can't
|do that, I'd suggest XDrawPoint simply because there is less protocol
|data and the primitive is normally quite fast (or should be).

Not for "billions" of points; when I was sending across about a
million points (roughly) I found that it took many seconds (more than
30 if I remember right, although this was R2) on a Sun 386i versus
under one for XPutImage.

If you need point granularity you can send two images across -- one
which is a mask of points to plot and the other containing the point
data and draw the data through the points.  This is still faster than
XDrawPoints for large numbers of points even though you're sending
more data over the wire.  This technique requires quite a bit of
server memory though.

jim frost
saber software
jimf@saber.com