> I wonder if there would be a way to make a Rebuild command for surfaces like there is for curves.

It might be easier to edit the number of control points or edit the points in the original edge curves before re-Meshing.

Michael,
Here is the same sink done in ONE MESH action. I'm amazed!
I took the profile shapes and added profile rings to allow the Mesh function to follow along.
So the path follows from one drain ring, around the sink, and back to the bottom drain ring.

I now have a seamless solid shape with (nearly) perfect surface contours.
Thanks for the insight!

Mike

(Framework on left consisting of open shaped vertical profiles and closed rings to follow them. Single Mesh result on right)

Hi Shaun,

> What determines the number of points on a surface when
> you click show points?

It depends on what technique was used to construct the surface - some surface construction techniques will create a surface that directly inherit the control point structure of the curves that were used to generate them, while some other construction methods may go through a kind of fitting process where the surface is refined until it reaches a particular level of accuracy.


> For example a default sphere shows 86 points. Since there are an
> infinite number of points on a surface I have a feeling MOI shows
> the least number of points possible in order to represent the
> curvature of the surface but still be workable. Is my assumption correct?

Yeah, actually a sphere is a special case - the sphere internally uses the minimum number of points needed to make an exact sphere surface but that does not allow for very good squishing, so when you turn on control points for a sphere it actually shows you the control points for a rebuilt version of the sphere with more points around it. In the future I want to make the number adjustable.

You can actually build a custom sphere with a particular number of points in it right now - to do that you would set up an equator circle and a vertical arc (see attached 3DM file) then use Rebuild on them with the # of points mode to set those curves up with the number of control points you want to have in the final sphere, and then create the custom sphere by using Construct > Revolve > Rail revolve - pick the vertical arc as the profile curve and the equator circle as the rail path, and then pick the revolve axis as the line between the endpoints of the vertical circle and you'll have a sphere with that number of points in it as the result.

If you want to build a flat plane with a particular number of points in it, you can use the Extrude command with the "Set path" option for that, see here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=1313.2

- Michael

Also re: spheres - MoI will only show you the "auto-rebuilt" control points for a sphere that is a full surface that does not have any trimmed out areas in it.

If you trim away a little piece of the sphere and then turn on control points, you'll then actually see the sphere's natural control points which look like this:



These points don't deform well though - it's basically 8 chunks kind of glued together and if you disturb these points you can easily make a sharp crease appear between the sections - that's why MoI will show you the control points for a rebuilt sphere instead when it is able to.

- Michael

Hi Shaun,

> I wonder if there would be a way to make a Rebuild
> command for surfaces like there is for curves.

Yup, that should be possible in the future - also it will be possible to extend Add pt to surfaces for adding in an extra line of points to one area of the surface. The way NURBS surfaces work they are always a rectangular grid of points though so you can't just add in a single point somewhere, you have to add in an entire row or column of points.

Basically surface control point editing is not a fully fleshed out area in MoI yet - because things like Boolean and cutting operations are the greatest strong areas of NURBS modeling, I've focused more attention on those strongest areas first.

The basic assumption is that if you like to do surface point editing, you will likely be doing that in sub-d modeling program instead of in MoI, since that is the strong area of sub-d modeling.

As time goes on I will continue to flesh out the surface control point manipulation toolset a bit at a time, but it's fundamentally limited because of that topological restriction I mentioned above where you can't just insert a single point anywhere you want, with NURBS you have to insert an entire row of points since a NURBS surface is defined by a rectangular grid of points. This places a big constraint on point topology, and it's the biggest reason why sub-d modeling became the method to use for that type of point cage manipulation modeling rather than NURBS surfaces.

- Michael

Hi Mike,

> I now have a seamless solid shape with (nearly) perfect surface contours.
> Thanks for the insight!

You're welcome, and that looks like a great improvement in your shape!

- Michael

"also it will be possible to extend Add pt to surfaces for adding in an extra line of points to one area of the surface"

Now we're cooking!

"also it will be possible to extend Add pt to surfaces for adding in an extra line of points to one area of the surface"

You can also just "Project" a line to the surface ;)

Actually what I think he's saying is we may get the ability to increase the number of points that define the surface. Not adding a curve to the surface like a projection.

Hi Shaun, yup that's what I meant.

- Michael

Hi Michael,

Thought I'd post a pic of how the sink object was used.
I'm happy to have done so much with it the trial time I had left, learned a lot.
In due time, I'd like to do a good quality render.



Kind of obnoxious for a bathroom sink, but it's the result of how MoI can allow quick visualization of an idea. (plug ;-) )

Hi Mike, wow you made a ton of progress, including the mechanics! That's a great result!

- Michael

Sweet concept Mike! I like it a lot.

Cheers

Thanks guys!!! :-)