I'm a huge fan of your scripts and just now work on a design that requires the translation from Subdivision Surfaces to NURBS.
I have one problem though:
Everything works great as long as only two edges meet to build a sharp edge, but in my model I have several places where more edges meet and I wonder if it's possible to solve that somehow?
Here is my Model in Softimage XSI with hard edges applied (the blue ones):
And this is the result in MoI with your script:
I probably could remodel all those edges by hand, but they are many and I wonder if you would have an idea how to deal with it automagically ;-)
If I preserve corners I get rather weird results that are not usable.
It basically would need to keep the rounding but make the corners sharp only where several cuts/corners meet.
Thought some more on how this could be implemented:
If recognising the cross-points automatically is a problem, maybe we could select the points we want to stay sharp before we apply the script?
But I guess you would still need to somehow pick up the continuity between the parts...
BTW. My illustration above from MoI contains some selection errors, in both cases there would be four hard lines that meet in one point if it would be the same as in XSI, but I also have corners where three hard edges meet.
If there is anything I can do to help, please let me know.
Another question:
I checked for a while now, but seem to be unable in MoI to separate an edge.
How would I go about separating edges that are not separatable by a polygon selection?
Like splitting one edge in a ring of polygons? Can that be done at all?
Sorry if I miss something obvious here... ;-)
Otherwise I would have to try if it can be done by separating the polygon edge before import...
my question was maybe unclear: I want to do the conversion from OBJ to NURBS, but want sharp corners inside for instance a Ring of polygons (just as a simple example, my real objects are more involved):
These are four polygons (a cube with top and bottom removed) and one sharp edge. I have not found a way in MoI to "disconnect" an edge like that so that the script can treat it as "sharp".
But somehow I feel it would be even better if we would not have to disconnect the pieces for sharp corners but could simply select the edges we want sharp and the script would work from there. The disconnecting has some disadvantages that I guess would be easier to solve with selected edges instead, since you would still have a whole, connected mesh.
I looked at the script but the math is over my head, so I can't directly contribute other than with some brainstorming on possible approaches and workflow.
now i understand, in Silo for example it's called "crease edges". I quickly created a polygon cube like you show, imported it into the free Fusion 360 (for hobbyists etc.) converted to T-Splines and then creased one edge. See attached image. Another one i have tried is to do the same and then refined the mesh in Silo and imported into Rhino trial with "MeshtoNURB" command, resulting in a high surface patches object in MoI, so not ideal...
So if Max could somehow implement a "crease edge" function for poly import and his subd script, this would be awesome!
awesome, thanks a lot - the good old techniques from the past before there was edge-weighting ;-)
That works pretty well for what I do at the moment, although it creates a tiny rounding instead of a really sharp corner.
Would you consider implementing sharp creases (for instance from an edge selection) or is that out of the scope of what you want to do with the script?
I would really love that feature.
it turns out it's not optimal to work with the multi-line-edges since they tend to create subtle wobbling and smoothing in places where you don't want them.
I can't use an OBJ mesh where the parallel edge-lines coincide completely (for a maximum sharpened edge), I guess the obj importer or MoI merges those away? But even with very small distance values, the Subdiv Script fails (no error message, it just doesn't do anything).
The smallest I seem to be able to go is 0.05 mm which still creates too much smoothness for some of my edges.
So I still would very much love to have a way to set completely sharp corners :-)
I was searching the forum here but didn't saw someone mentioned something regarding ImportObj script.
It seems like, if you have your objects in your other 3D app not perfectly world centered but instead somewhere in the scene - the ImportObj seems to completely ignore
object position/scale when imported in Moi3D, it will just import it in the center of the Moi3D scene. When you export back from Moi3D to other 3D app the object will not anymore be in the original position but instead centered in the middle of the scene.
What i usually do is when i model something in Maya and i see something would be just easier/faster/better to make in Moi3D, i will block it out and export as Obj then using ImportObj script import in Moi3D. At this point the object will not be anymore in original position/scale/rotation so when i am done working in Moi3D and export back to Maya i have to position/scale/rotate the object back in the original place again.
Is there a way currently for Moi3D and other 3D app get along nicely when import/export your object and for object to remember position/scale/rotation instead of, when you import obj, Moi3D to auto center it?
To use it, modify your keyboard shortcut to give the parameter "exact", by adding it to the end of the shortcut separated by a space, so your shortcut should read like this:
Thanks you so much for this, Michael!! This is now extremely helpful! Thanks!
Actually super cool to have both options since sometimes i want to have object in the middle when importing in Moi3D but most of the time i really need to be
at original position. Nice.
Hi glmr, please post the 3DM model file that you are trying to smooth when you see the error.
My guess though is that you have some faces in your object with 5 or more boundary edges on them. The converter will not work on that type of geometry, I think it requires all faces to have either 3 or 4 sides (triangles or quads).
Hi glmr, well I can see right away that you've got a top face on your extrusion which has 24 holes in it, which right there is not suitable for subdivision smoothing.
In order to do sub-d smoothing, your object needs to be made up only of 3 or 4 sided faces with no inner holes in any of them at all. So instead of one single face on the top with trimmed holes in it, the top part of an object like that needs to be tiled and made up of a bunch of smaller 4 sided faces that sort of flow around the holes.
Also you'd typically have an angular cage-like object as the base object to be subdivided, with all edges just being line segments, not starting out with curvy outlines like you've got there.
Sub-d modeling is a really different approach from a drawing based one like you're showing there.
try to export the file to .obj-format to get triangles and quads. Then reimport the result with the obj-importer written by Max Smirnov. After that - run the script:-)
Did you install a shortcut key in MoI Options icon?
For example: Select Options / Shortcut keys,
and add a new entry of your choice, such as Alt+F in first column, then _Subdiv_beta9 in the next column.
or for example, Alt+/ _Subdiv_beta9
The prefix _ must match the prefix of the _Subdiv_beta9.htm and .js files. _ is not required, but its presence or absence must match.
Then close and open MoI again, load a solid polygon, such as Box, select it, and type in the shortcut key combo,
for example hold down the Alt key and type F.
(I now use Max's custom ui for Ext.scripts, instead of shortcut keys, and also use _ prefix for the non-basic MoI scripts)
Either method, or both methods may be used.
MulticornerMeet_MoI.jpg
