Hi Will,

> okay, perhaps I just meant >handle bar< editors for the existing points - similar to Rhino...

You mean like the HBar command in Rhino?

The main useful part of HBar is actually already built in to MoI - you can activate it by dragging on an unselected curve that has control points turned on.

For example - if you have this curve, if you click and drag from here:



You will get this dragging effect, same as if there was an HBar there and you were dragging the middle point of it:



This allows you to drag a point directly on the curve from where you dragged to a new location, you sort of grab a point directly on the curve with this mechanism. It's basically a way to manipulate several nearby control points all in one single motion, so it can be useful for kind of roughing out and making big changes to a shape.

This is a lot better than a dedicated command because it is always implicitly available just with a drag gesture on an unselected curve (if the curve is selected then you will drag the entire curve). HBar as a dedicated command is really quite awkward, you have to worry about firing up the command and repeating it a bunch of times... Also HBar in Rhino requires more clicks - you can't just click and drag on a portion of the curve, you have to click once to place the handlebar, and then click again on the handlebar to drag. This actually wasn't the case when I originally wrote HBar, it looks like that got a bit messed up in Rhino.

Re: full Bezier editor -

Doing a full bezier type editing system would tend to greatly exacerbate the original problem here about having multiple joined segments.

A Bezier editor creates curves that are made up of tons of little separate individual curves joined together into a long string. Each little piece is made up of 4 control points. It forces shared tangents by moving points together to be in a straight line between each little piece, but it generally does not produce shared curvature between each piece. So I'm not really planning on doing anything like that, it just does not create as high quality of smooth curves as the current NURBS system in MoI.

NURBS were essentially invented as a solution to this problem with chaining together lots of little individual Bezier curves! The mathematics are related, I mean NURBS builds on a lot of Bezier mathematics as a foundation, but it provides a way to have a smoother curve when you have more than 4 points.

Doing a Bezier style editor would be kind of taking a step backwards technology-wise...

- Michael