Is there a way in Moi to create planar (square or rectangular) surfaces with a specified number of points.
For example a square planar surface with a grid of 4 points by 4 points ?

I'm thinking if I could do this I could mold some of the more difficult surfaces I need by point pulling ?

If not square is there another way to create a circular surface with specified number of points.

Hi Kevjon,

For square yes...
Search on the discussion forum

For another shape, try your self with the same method.

Hi anis I searched the forum for "square" but couldn't find any threads with the same question as I have.

can you think of any keywords to assist in the search ?
I'd be most interested in reading the thread you refer to.

Hi There...

Find attached file.
You have to create 4 curves use Freeform>Control Points
Then network.

BTW, the only one that good in searching a thread is Michael.
Would you lke to share how you can find a thread that "looks" very easy ?

Hi Anis

Thanks for the help, you've given me and idea that helped solved this.

I created a free form curve with 5 points then arrayed the curve 5 times and used the loft command to create the squarish surface.

Result is on the right

Cheers

Hi Kevjon,

In my previous example, I create a single curve. Show the grid line, then I can easily use it as distance point reference. But you way looks work also. It will be cool to see the model that you want to create or when you have done for it.

Ups....,

Base on your image, I can see that the number of points in your curves not same compare to points in the surface.

No its the same 25 points in both.

I find that using traditional loft, network and sweeps sometimes warp, twist and buckle surfaces that I want to create so thought this might be a good approach for those difficult to model nurbs surfaces where you could kind of sculpt the surface like sub'd and then build other surfaces off that shape. I don't want to spend $1500 on Rhino and Tsplines to do those few tricky surfaces.

The model I'm trying to build is this one
http://moi3d.com/forum/index.php?webtag=MOI&final_uri=post.php%3Fwebtag%3DMOI%26amp%3Breplyto%3D2350.0

I was thinking of using this technique on the upper part of the fuselage to sculpt the required shape.

Hi Kevjon,

>> No its the same 25 points in both.
Yes, the number of points same, but the distance is not similar. See the red line below :



>> http://moi3d.com/forum/index.php?webtag=MOI&final_uri=post.php%3Fwebtag%3DMOI%26amp%3Breplyto%3D2350.0

You provide me a wrong link...

Distance doesn't really matter for me as all points will have to be adjusted and tweaked to create the shape I want anyway.

However your technique is good for getting a even distribution of points if that is required.

Hi Kevjon,
You can also create a "GRID" of lines in both directions, a hatch", then run "network" to create a surface. The surface will have points at the grid intersections. So with Array you can create various shapes with exact pointing very fast. If need a picture I'll post it in a bit.

You can then trim that surface with another shape curve to get more exacting shapes of surfaces with the point structure desired.

You may want tot get the "ShrinkTrimmedSrf" command from the Petr's MoI page on the resources tab to shrink away the points left from a surface trim. Although the point structure remaines "Primitive", the surface will be a shape you wanted originally.

Mucho Controlo!

Hi Kevin,

Probably the easiest way currently to make a plane with a particular number of points is to draw 2 curves at right angles to one another, and then use Extrude with the "set path" option, see here for an example:
http://moi3d.com/forum/index.php?webtag=MOI&msg=1313.2

The result of Extrude with "set path" will create a surface that has control points that are an exact combination of those 2 input curves. So if you draw the original curves with as many points as you want in that one direction that should do the job.

The circular/radial type equivalent of that is to use Rail revolve - it is similar in the respect that the number of control points in the resulting rail revolve surface will be a direct combination of the 2 input curves. The main difference between it and extrude is that there is a revolve axis specified for rail revolve and the surface is kind of pivoted around that axis.

In the future when there is a "rebuild" command it will probably be the main one to use for this task of reconstructing a plane with a specified number of points to deform, but I don't have that yet.

- Michael

Thanks Burr and Michael.

That is a better solution than what I had and exactly what I was looking for !

I guess the next question is now, is there any techniques to add additional rows of control points to a surface after you create it ?

I've tried splitting a surface in half by trimming and boolean it back together but that wasn't the answer.

Kevin, Just add points, Edit>Add pt, to your curves that you used for the extrude, that should do it.

Cheers

I havnt followed through with Michaels solution yet, but using mine you could create a much larger surface than needed. Then trim out your initial shape, and DONT use "ShrinkTrimmedSrf", then manipulate your points of the new shape. Then when you want more points, "Heal" the surface by drilling down to the edges and deleting them and the original large surface returns with added points!

I know, I know... Hoky. I havnt tried it with multiple "Odd" shapes yet, only one large square cut down to a smaller square, but in theory should give the ability to keep adding back more points tpo the outer edge of the surface.

Thanks Danny,

Thats a handy tip that does work while the surface is still planar and before you started manipulating/moving points on the surface. After you've moved a couple of points on the surface around, adding additional control points to the original curves doesn't have any effect on the number of points on the surface.

I'm now finding that once I start molding my surface to shape I sometimes need additional rows of points to refine the shape a bit more. Is there a technique that could be used to add the additional points ?

Burr

I like your thinking on this but I'm lost.

I've created a surface of 4 points by 4 points and started moving some of the points on the surface around. I've then trimmed the surface with another curve. All good so far. I've then selected all the edges of the trimmed surface and deleted them but all I get is the original surface back before trimming with no additional points.

Are you able to elaborate a bit more on your suggestion, it sounds interesting ?

Hi Kevin, there currently isn't any way to add points to a surface after you have already been messing around with its points.

You have to add enough points to your original curves.

It is on my list of things to make "Add pt" work on surfaces as well as curves though.

- Michael

Kevin,
After thinking about it and reading your reply to Danny, I realized what I was talking about isnt quite what you were asking. My method only adds more rows and columns to the outside of the shape your using. I'll post a vid as it may work for you in another area though.

Burr the video king :)

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