Re: Bug in Graphics output of Circle primitive?
- To: mathgroup at smc.vnet.net
- Subject: [mg62926] Re: Bug in Graphics output of Circle primitive?
- From: Yves Klett <yk at despammed.com>
- Date: Thu, 8 Dec 2005 03:27:36 -0500 (EST)
- Organization: Comp.Center (RUS), U of Stuttgart, FRG
- References: <dn5o7s$nih$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Dear Mathgroup,
thank you very much for your suggestions. I will have to avoid using
those wild scalings when dealing with arc primitives and use some
workaround as described by your posts.
With best regards,
Yves
Yves Klett schrieb:
> Dear Mathgroup,
>
> I stumbled upon a strange (and suspicious) graphics output when
> displaying arcs with small angular length.
>
> If I evaluate the following lines:
>
> r = 10000;
> gx = Circle[{r, 0}, r, {179°, 180°}];
> Show[Graphics[{gx, Point[{0, 0}]}], Axes -> True,
> PlotRange -> {Automatic, Automatic}, AxesOrigin -> {0, 0}];
>
> (or the same in plain text format...)
>
> r=10000;
> gx=Circle[{r,0},r,{179\[Degree],180\[Degree]}];
> Show[Graphics[{gx,Point[{0,0}]}],Axes\[Rule]True,
> PlotRange\[Rule]{Automatic,Automatic},AxesOrigin\[Rule]{0,0}];
>
>
> I get the point as specified at the origin {0,0}. The arc though does
> not intersect at the origin as it should IMHO, but somewhat left of it.
> Same thing occurs for arbitrary values of r.
>
> There might be some precision problem of the postscript output
> concerning the Circle primitive when very different axes scaling is
> used, but any enlightment would be appreciated.
>
> I am using V5.2 on windows. Any hints or tips to get rid of this faulty
> output would be very welcome,
>
> Yves Klett
>