Set-coords arc floating precision

[Nate Chodosh]

Thanks for the welcome!

Right, I know that rounding has to occur eventually but if I extend my line
ltk seems to be able to draw an arrow head that looks rotated to a
precision greater than the 45 degree increments allowed by a single pixel
long line. So I'm wondering if it's possible to get that precision without
the long "tail" on the arrow. Googling has turned up this
<http://www.perlmonks.org/?node_id=800025> which seems to indicate that my
idea would work directly in tk so does ltk perform the rounding earlier?

Thanks,
Nate

On Sun, Oct 4, 2015 at 5:24 AM cage <cage at katamail.com> wrote:

> On Fri, Oct 02, 2015 at 08:55:17PM -0400, Nate Chodosh wrote:
> > Hello,
>
> Hello!
>
> > My name is Nate. I have never participated in one of these lists before
> so
> > I don't know the protocol so I apologize if this isn't the appropriate
> > channel.
>
> No problem! Welcome! :)
>
> >
> > I am working on an application where I need arrows on the end of arcs,
> > which I am accomplishing by adding very small lines to the end points.
> > However I think I have discovered that set-coords when used with an arc
> > won't update the position unless the coordinates are integers which makes
> > my approach impossible. Is there a workaround for this issue?
>
> No sure I can see the point here  as you did not provided any code but
> if you are rendering on the screen,  as I guess, you will have to deal
> with rounding anyway: if you want to draw at x = 1.5 (for example) you
> have to decide which pixel draw (x = 1 or x = 2) as there is "nothing"
> between pixel.
>
> > Thank you,
> > Nate
>
> Bye!
> C.
>
>
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