finding point on a map

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Lou Lipnickey - 13 May 2004 19:28 GMT

I am trying to calculate the location of a point in a plane given a
start point, a distance and an angle. I can't remember enough geometry!

So if I have a point x,y and a distance of d and an angle of a where:
x,y = 100,100
d = 20
a = 30 degrees

can anyone provide a formula to find the end x,y?

Thanks in advance - Lou

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Andrew Thompson - 13 May 2004 19:38 GMT

> I can't remember enough geometry!

So you ask on a Java GUI group?!

Why not ask on (or better still,
search first) a geometry forum,
like, ferinstance..
<http://google.com/groups?group=geometry.forum>

Not that hard now, is it?

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Lou Lipnickey - 13 May 2004 20:04 GMT

Semi related, but thanks for the pointer

>>I can't remember enough geometry!
>
[quoted text clipped - 6 lines]
>
> Not that hard now, is it?

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Roedy Green - 13 May 2004 20:47 GMT

>So if I have a point x,y and a distance of d and an angle of a where:
>x,y = 100,100
>d = 20
>a = 30 degrees

You can use AffineTransform if you don't want to refresh your trig.

to convert cartesian <-> to polar co-ordinates see
http://mindprod.com/jgloss/coordinates.html
and
http://mindprod.com/jgloss/polar.html
and
http://mindprod.com/jgloss/affinetransform.html

That last entry got considerable new work a few days ago.

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Coaching, problem solving, economical contract programming.
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Sergio - 14 May 2004 19:35 GMT

> I am trying to calculate the location of a point in a plane given a
> start point, a distance and an angle. I can't remember enough geometry!
[quoted text clipped - 7 lines]
>
> Thanks in advance - Lou

x2=x+d*cos(a)
y2=y+d*sin(a)

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finding point on a map

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