From:	XXguille AT XXiies DOT XXes (Guillermo Rodriguez Garcia)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Odd problem...
Date:	Wed, 19 May 1999 20:12:25 GMT
Organization:	Telefonica Transmision de Datos
Lines:	27
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References:	<19990519053901232 DOT AAA56 DOT 87 AT mike-s-toy>
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To:	djgpp AT delorie DOT com
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El día Wed, 19 May 1999 00:31:36 -0500, "Roy Taylor"
<rtaylor AT nextsteps DOT com> escribió:

>I have run into a tricky problem while writing a polygon draw function.  It
>seems to work fine in real mode under my MS compiler (but that won't cut it

That just shows how bad MS is :-)

[...]
>    for(i=0;i<=200;i++)
>    {
>        ScreenClip.Start[i]=0;ScreenClip.End[i]=320;
>    }

You are overrunning the array, which only has 200 positions. You are
writing from 0 to 200, that is, 201 values; the six Point objects are
declared just below the HLineList, so when you do this you overwrite
the points, thus getting incorrect values.

BTW: the values you get are the same each time you run this program,
povided you don't change any compiler options.

Regards,
GUILLE
----
Guillermo Rodriguez Garcia
XXguille AT XXiies DOT XXes (ya sabes :-)

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