Path: chuka.playstation.co.uk!news
From: "Mark Wilson" <m.wilson@dial.pipex.com>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: VSync return values
Date: Thu, 19 Mar 1998 18:56:15 -0000
Organization: PlayStation Net Yaroze (SCEE)
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Help, something weird is happening...

I've hacked together a 3D starfield, and the first method of drawing the
stars I used (using a GsSortLine to draw a line of one pixel's length) was a
bit slow, so I tried using a buffer in main RAM, drawing all the stars into
that, and then using LoadImage to shove it all into the current display
buffer.

This seems to work fine except for one thing. At the top of the screen I'm
using the built-in font to print the number of frames elapsed, the number of
lines since the last VSync, and the maximum number of lines since VSync that
has so far occurred. Occasionally, the text seems to glitch for one frame,
and the maximum number of lines leaps to some huge figure, like 30000 lines!
The stars don't seem to be affected by this at all.

Any ideas as to what's causing this?

Mark Wilson