Your request is quite generic. Perhaps you can show what you got so far, and explain where you are stuck more precisely.

     My request is not generic, it is quite specific (quoting the Processing reference pages at one point as a code example).  bezierPoint can only be used with one curve apparently, but I am looking to find a normalized approach to finding a point along multiple connected curves.  Hence my interest in geomeratve or other approaches. 

    However, I have looked at the geomerative library and due to sparse documentation, I do not understand it.  I take it that it creates or operates on SVG files, but I don't understand how it breaks or builds back up the SVG information into paths, shapes, polygons, commands,etc. There is a method in the RPath class, however, that does look promising:

getPoint

public RPoint getPoint(float t)

Return a specific point on the curve. It returns the RPoint for a given advancement parameter t on the curve.

Specified by:

getPoint in class RGeomElem

Parameters:

t - the parameter of advancement on the curve. t must have values between 0 and 1.

Returns:

RPoint, the vertice returned.

A question to ask is if a RPath encompasses a collection of curves and if the parameter t applies to a specific curve or to the whole collection.

I think that PhiLho meant generic in the sense that it lacked some details that would help others give sound advice..

For instance you don't state

1. whether you want a smooth transition as you pass from one Bezier curve to the next or whether cusps and knots are allowed.
2. You say "I would like to use BezierPoint to find a point located some distance along the second curve and display a small circle around it."  you don't explain why, what about the other two curves? It was certainly a question that occured to me.
3. you say you want to connect 3 curves, why only 3? Will there be situations where you want more or less than 3?
4. Bezier curves can be used to create either 2D or 3D splines. I assume you want 2D but I might be wrong
   

Thank you PhiLho and quarks for your quick and thoughtful responses.

In November I posted to the Processing forums a listing titled "String art design using processing".  The posts in this listing (bezierPoint issues (multiple curves)) is a continuation of that.  I will copy it below:


String art was very popular during the 1970's. It involves pounding nails into a wood board at certain intervals, then winding string(s) around the nails to achieve an artistic effect. A video that demonstrates the making of a string art piece is given by this link: string art video.  For pictures of string art works, click on the following link: string art images.

I am interested in converting clip art to string art patterns.  The clip art would supply curves, and then I would need to mark positions for nails along the curves.  Finally, I would care to simulate the weaving of thread around the nails.  Any code snippets to facilitate this process would be appreciated.

*******************************************************************************************************************************************
quarks, the code you provided for me does what I described in this latest listing.  You were right on the mark.  I merely commented out the animation and replaced it with some fixed values to get the effect that I desired. 

The next step, though, is to combine any number of lines, arcs, ellipses, and circles along with bezier curves in a path.  In other words a "pt value from 0 to 1 in the draw() function" (see code) locates a point some distance from the beginning and ends of the path.  Again, the code you provided, quarks, is a wonderful step towards this, but geomerative may need to be used (just a hunch..) unless your code could be abstracted to handle the other entities.

A final step would be to import coordinates from a SVG editor for the path entities.  This is where I am wondering if geomerative would also need to be used.

I apologize for any confusion in my last post to this listing.  I am new to Processing.  I am talking about strictly 2D splines.  Cusps and knots may be OK, but I honestly can't visualize it at this point.  Any number of entities could be combined in a path.

Craig

P.S.  The included image demonstrates what I mean by a path as opposed to a collection of bezier curves.

I am not familiar geomerative library so I can't offer any solutions based on that library. I suggest you post a topic in the Contributed Library forum asking if anyone knows of any additional documantation/examples/tutorial for this library.

So we are not talking about creating smooth Bezier splines because you want to incorporate other curve types. This makes it easier because we don't have to worry about smooth transitions, for instance in your diagram above if it was the other end of the arc connected to the line there would be a cusp.

This boils down to
each section is an independant entity having no effect on the shape of adjacent entities, only their position

Since Processing provides a number of functions to render arcs, lines and Bezier curves then a lot of the work is done for you. The solution is fairly straightforward but involves OOP programming. It can be done without OOP (classes and objects) but the code would not only be messier, it would also be difficult to maintain and extend it.

If want to investigate and use the geomerative library further then thats fine. If it does not suit your needs and are willing to build the solution from scratch then I am happy to help create a solution with you in this forum (hopefully others will benefit from such a discussion). If this is the case drop a PM to me and I will come back to this topic.