elliptic movement?

I have a point in 3D that should move along an elipsis where the lenght of 
the elipsis should be user specified. I have a time variable that runs from 
0.0 -> inf. Any ideas on how I updated the point position on an ellipsis 
based on this parameter? 

0
mlt
2/28/2009 7:54:15 PM
comp.graphics.api.opengl 7063 articles. 0 followers. Post Follow

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mlt a �crit :
> I have a point in 3D that should move along an elipsis where the lenght 
> of the elipsis should be user specified. I have a time variable that 
> runs from 0.0 -> inf. Any ideas on how I updated the point position on 
> an ellipsis based on this parameter?

Hi
That's not an OpenGL related question at all, but, if the axis of your 
ellipsis is oriented according the Ox and Oy axis:
x=a.cost
y=b.sint
where a and b are the half axis.
Hope this helps
Cathy
0
Cathy
2/28/2009 9:03:29 PM
"Cathy" <no@no.fr> wrote in message 
news:49a9a6a2$0$25584$426a34cc@news.free.fr...
> mlt a �crit :
>> I have a point in 3D that should move along an elipsis where the lenght 
>> of the elipsis should be user specified. I have a time variable that runs 
>> from 0.0 -> inf. Any ideas on how I updated the point position on an 
>> ellipsis based on this parameter?
>
> Hi
> That's not an OpenGL related question at all, but, if the axis of your 
> ellipsis is oriented according the Ox and Oy axis:
> x=a.cost
> y=b.sint

What does "." mean? Is it multiply:

x = a*cos(t)

? 

0
mlt
3/1/2009 9:42:39 AM
mlt a �crit :
> 
> "Cathy" <no@no.fr> wrote in message 
> news:49a9a6a2$0$25584$426a34cc@news.free.fr...
>> mlt a �crit :
>>> I have a point in 3D that should move along an elipsis where the 
>>> lenght of the elipsis should be user specified. I have a time 
>>> variable that runs from 0.0 -> inf. Any ideas on how I updated the 
>>> point position on an ellipsis based on this parameter?
>>
>> Hi
>> That's not an OpenGL related question at all, but, if the axis of your 
>> ellipsis is oriented according the Ox and Oy axis:
>> x=a.cost
>> y=b.sint
> 
> What does "." mean? Is it multiply:
> 
> x = a*cos(t)
> 
> ?

Hum... sorry, yes the dot means multiply.
0
Cathy
3/1/2009 4:23:24 PM
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