Hi Rainer,

> I am missing something like 'Bezier Handles' which I can bend and stretch
> independently from the right or left tangent.

Select your joined curve, and then use Edit / Show pts to make handles visible to adjust.

The start or end tangent of a segment is defined by the first two or last two points.

So to make the start and end tangent defined independent from one another, you need to have a segment with at least 4 points in it - use Edit / Add pt to add points if you only have 2 or 3 points currently in the segment to get more freedom to adjust it.

If you're still having any difficulty with this, could you please post an example model or screenshot that shows what you're trying to do?


> Like a 'ctrl' click when I do not wish the knot interpolated. Am I missing something?!

You should be able to use Ctrl+click to do this in either the Draw curve / Freeform / Control points or Through points commands. You can either use Ctrl or you can also click the "Make corner point" checkbox that shows up in the upper-right corner of the window where various command options are shown.

If Ctrl+click is not working for you, could you please describe what you're doing in a little bit more detail?

- Michael

Now I understand the workflow.... sorry for that.... Adding points gives me all the 'handles' and behavior I need. I just expected a different visual... Then the Ctrl failed on me because I did not recognize instantly what the 'make corner point' relates to... The 'Make Corner Point' is there for that special case where the next point is a 'straight' target.

Thanks for the hints!
Rainer

PS:Rhino is a pita by comparison....

Hi Rainer, no problem. For version 2 I would like to improve some of these things to make them a little more familiar to 2D illustrators.

Like right now if you want to convert a "smooth" control point into a corner one, you have to actually insert a new corner point and delete the old smooth one. For version 2 I think that I'd like to put some kind of UI that shows up when you select a point, to let you switch it between "corner" and "smooth".

> The 'Make Corner Point' is there for that special case where the next point is a 'straight' target.

Yup, basically it will end the current smooth segment that you are drawing and start a new segment coming off of that corner point. It is the same thing as if you ended the curve there, and then drew a new curve with the start of the new curve snapped on to that same point and then joined the new curve to the old one.

You can use Edit/Separate to break the combined curve into individual segments later on if you need to.

That same option (which holding down Ctrl and clicking is a shortcut for) also works with Add point as well as the curve drawing commands, if you want the new added point to be a sharp point when you move it around later instead of a smooth curve control point.

Let me know if you get stuck on anything else, it is actually really good feedback for me to hear what things don't quite click immediately, it can help give me ideas on how to simplify and streamline stuff in the future.

- Michael

@lemo : hang on it ;)

Thanks again for the pointers. Now I ran into a different problem. The traced path worked out great now. Real well I might say!!!
Now.... the only challenge is to loft a small bump along the two rails I made. It's a 'WWS' like shape with straight and curved curve parts. SO there is a fair amount of 'up and down' going on.
The problem is that the poor loft algorithm creates a mesh which is not really following the curve. Mostly it does, but then, in areas with low point density, it meshes out and reaches across the curve borders. I tried to get that done in Rhino and could use 'SLASH' to cage the segments into a more meaningful mesh but that also yielded a lot of shading problems and thus is pretty useless as well. Man, this 'little' task seems to start and digest myself. I try and get a middle curve and simply extrude a circle along it and see what happens.... Uggly... all very uggly hahaha.
Rainer

Hi Rainer, can you post the .3dm model of these curves that you are trying to surface?

That would help me give you some more specific advice.

It can be hard to do a long wiggly thing without having things bunch together as the profiles slide along the rails.

- Michael

Hi,

One of the greatest method of handling curve points I've seen in graphic program is double-clicking on the point to toggle it's state (corner, tangent, etc..)

Also a color code for indicating node type would be great.

Regards,

Marc

Here is a link to the screenshot I made this morning. It shows the slashes I made with RHino4 to coax the machinery into producing an acceptable surface. I love the idea of colors and the ability to double click and switch from corner to tangent point. But I must say that after working with it for 5 minutes the current way to handle it becomes second nature. However, a smarter algorithm to sweep between two rails would be fantastic. I can see that this is a rather difficult endeavor as it requires a lot of intelligence in the algorithm.

www.onesmall.com/stuff/moitest.jpg

Rainer

hi lemo : Seems a sweep with only one rail will be more appropriate in this case?

Hi Rainer, the other thing for curve point manipulation that is kind of hidden is the "drag point on curve mode", this allows you to position several nearby points by clicking and pulling directly on an unselected curve that has control points turned on. You may be interested in this as well, there is some more info here: http://moi3d.com/forum/index.php?webtag=MOI&msg=744.16

> However, a smarter algorithm to sweep between two rails would be fantastic.
> I can see that this is a rather difficult endeavor as it requires a lot of
> intelligence in the algorithm.

Yeah, it is a kind of tough area.

However, I do have some experimental code which is currently disabled, that basically tries to do a similar thing as Rhino's "add slash" but doing it automatically by finding shared perpendiculars between the 2 rails and using those as alignment points.

It actually worked pretty well in many cases like you are showing there, but it could also get confused sometimes. It needs a bit more work before it is finished so I pushed it off to v2.

But if you want to post the .3dm file with those curves, I could enable it and give it a try to see if it would have processed your sweep better.

One last FYI - it can be handy to bring stuff between MoI and Rhino for different types of processing. I just wanted to make sure you knew that you can just use copy and paste between MoI and Rhino to transfer objects back and forth really quickly, you don't need to even save to a file. When pasting from MoI into Rhino, make sure to leave MoI running while you do the paste.

- Michael