From:	Kev <krugman AT blueyonderspammaps DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: ALLEGRO: help with ARC
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Date:	Mon, 24 Feb 2003 17:20:23 +0000
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On Mon, 24 Feb 2003 12:50:56 +0000 (UTC), "helen"
<lab_darzo AT libero DOT it> wrote:

>
>I am using Allegro with DJGPP on a win98 OS.
>Everything works fine, but I can't get this to work properly:
>(look under for more questions and details)
>
>/*
Snip
>HELP says
>void arc(BITMAP *bmp, int x, y, fixed ang1, ang2, int r, int color);
>Draws a circular arc with centre x, y and radius r, in an anticlockwise
>direction starting from the angle a1 and ending when it reaches a2.
>These values are specified in 16.16 fixed point format, with 256 equal
>to a full circle, 64 a right angle, etc. Zero is to the right of the
>centre point, and larger values rotate anticlockwise from there.
>
>
>thank you
>
>helen
>
>contact me also at skyboxNOSPAM AT infinito DOT it

The start angle, ang1 is 30, this is a twelth of a circle.
a twelth of 256 is 21.3 recurring

the end angle is 300 this is 5/6 of a circle and 5/6
of 256 is 213.3 recurring

So, I would say that ang1 should be 21.333
and ang2 should be 213.333

Never used the arc() function myself, but this feels about right

Kev.

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