Rhino question

[Alnico]

Regarding the XY (2D) outline of a solid-body (Strat-style)...I did the first version by rough freehand, and then fine tuning and snapping each point to a 1/10th of an inch. I then ran the List command, and I notice on the output that many of the points on that list aren't *exactly* what I have on the screen. For instance an edit point which I'll click on and shows as say: 12.5, 2.2, 0 might show on the list text output as: CV[24] 12.51678490876, 2.19874572345, 0 ...very close but not exactly. Why?

I then took the text of that list copied it to a text editor, cleaned out the brackets and stuff to make it into a script, made some parts exactly symmetrical, deleted the old curve and imported back in using a script like this:

!_-curve
12.01678490876, 1.99874572345, 0
11.00001234568, 1.57894561231, 0
;etc
;etc
;etc
1.098745612313, .254563123456, 0
_enter

(This is just a general example, the real one is much longer)

When I click on the edit points of the curve from the newly imported curve script, they're close, but don't match exacly. What's up?

I guess my first question should be: how can I have the List show the edit points (CV) with only 2 or 3 decimal pts as on the screen? And how can I get the result of the script import to show the edit pts exactly?

(oddly enough, when I do a List command again, it shows the edit pts exactly as on the script as they went in)

[turmite]

Al can you zip the original, and the new files and post them? It is so much easier to see than to guess?

Mike

[RandK]

The short answer is that when you make an interpolated points curve, a nurbs curve is created that goes through those points but those points don't become either control points (CV) or edit points which you can then manipulate via dragging etc.

[Alnico]

Thanks! BTW, while on the topic of Rhino, is anyone using the Smooth command on your curve lines to even things out? If so, what smooth factor?

[RandK]

Didn't know about smooth; I'm not sure how it's different. Help doesn't say much. I use fitcrv, rebuild and fair sometimes, especially if I've done something that has multiplied the number of control points and it needs to be simplified. Often I need to split the main curve into pieces and do them separately because it will do things like round off the cutaway horn if it is part of a whole body curve but not if it is a smaller chunk. Showing the curve hairs and manually fairing the curve (smoothing the hairs) works well and allows you control over areas which need work without messing up the rest or splitting the curve.

[turmite]

Originally Posted by Alnico Thanks! BTW, while on the topic of Rhino, is anyone using the Smooth command on your curve lines to even things out? If so, what smooth factor?

Al I have used smooth and rebuild both. The settings will be determined by more than a single factor, and like RandK said, it will change some things. I personally have gone to using create curve using freeform and controlpoints. I pick as few points along the curve or object as I can get by with and then turn control points on to manipulate the new curve to what I want.

I just finished modeling a guitar that was sent to me as a dxf. The dxf was no where close to being smooth, lots of facets on the outside curves. So I simply used the method I just described to you and made a very nice smooth product.

My problem, well actually one of my problems with Rhino, is that are so many different ways to get to the same place that it is confusing. So I decided to try as many as I could figure out, then used the ones that best fit the way I model. My models are slowly getting much better.

Mike

[spoiledbrat]

You may have already tried this, but if you have a rough polyline, and you want to convert it into a single curve, try "refit to tolerance" under "curve edit tools". This will convert your line into a very smooth line, and display the deviation from the original curves in the dialog box.