Dragging and changing a curve (image)

[Beat Cornaz]

>I know that Alejandro has developed a bezier function for RR. It is very cool.

>If you want to just plot a known function, I would recommend my
>favorite graphics tool, Turtle Graphics.

>The code to implement TG is on my web site at
>http://home.infostations.net/jhurley/ under Turtle Graphics.

>Jim


Thanks Jim,
your turtle Graphics works fine from what I've tried and is a 
valuable tool for me. It doesn't solve the problem I'm facing though.

I want to be able to change the shape of a curve by interacting with 
it on screen with the mouse. At the same time I need to know the 
algebraic formula of the curve (the changed one (the new one)) in 
order to do calculations with it. Let's say I start out with y = 
3x^0.9 + 12. As soon as I change the curve with the mouse, I need to 
know the new formula (f.i. y = 3x^1.2 + 33).

      The curve is just a visual rerpesentation of something on the 
screen, but needs to changed a lot. Of course I can do that with 
sliders (that's the way I do it now) but it would be so much neater 
to be able to click and drag-change the curve.

I'm VERY INTERESTED in the Bezier function by Alejandro. Where can I 
get that one?

** If you keep your eyes off of your goal, you'll see mostly obstacles.
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