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From: jan@golf.canberra.edu.au (Jan Newmarch)
Newsgroups: comp.windows.x
Subject: Re: XDrawLine doesn't draw lines! Looking for help.
Message-ID: <jan.664762218@golf>
Date: 25 Jan 91 00:10:18 GMT
References: <1991Jan23.235111.23319@rodan.acs.syr.edu>
Sender: news@csc.canberra.edu.au
Organization: Info Sci & Eng, University of Canberra
Lines: 23

In <1991Jan23.235111.23319@rodan.acs.syr.edu> rshankar@top.cis.syr.edu (Ravi V. Shankar) writes:


>  I seem to be running into a problem when I use XDrawLine to draw a set
>  of lines. My program is pretty basic. It reads from a text file
>  4 values at a time and draws a line using the read values as coordinates
>  for the two endpoints.

Standard question, standard answer: you MUST wait for the first expose
event before attempting to draw. See e.g O'Reilly vol 1 (Xlib Programming)
section 3.2.14 When can I draw?

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  Jan Newmarch, Information Science and Engineering,
  University of Canberra, PO Box 1, Belconnen, Act 2616
  Australia. Tel: (Aust) 6-2522422. Fax: (Aust) 6-2522999

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