Need Help Cutting Peices out of a Sphere

[steve-j]

Hello Everyone.  Maya Noob here with big plans for this software.

Anyway, What I'm trying to do is Create a sphere (Earth)  and devide it into plate Tectonics.  I want to have an independant shape for each plate, all coming together to make the entire sphere. 

I am looking for the fastest/easiest way to do this.  I'm not sure of the right way, but here's what I've attempted so far before I got stuck.

So far I have Applied an image of the fault lines onto a sphere using the hypershade.
Then I traced the fault lines by making the sphere live, and Created a curve that followed all the fault lines.
Is there an easy way to use that curve to cut peices out of the sphere?  Polygons or nurbs, I don't care.

Can I do it with shatter?  Shatter makes really nice peices, but so far I can't figure out how to shatter an object using a custom map (like fault lines).  Is that possible?

OR.  Is there a better way of doing it all together?  The goal here is to have an earth broken into tectonic peices.  Being a noob, I hope I'm just missing out on an easy tool here.

thanks for your help in advance

[thnkr]

Start simple; Do all your modeling on a planar model, then bend it into a sphere.

[steve-j]

Ok,  I could probably get all the peices modeled right as a plane,  but I am unaware of how to take those flat peices and wrap them into a sphere nicely.  please forgive me for my lack of knowledge, I have been studying,  but there's alot to remember.

Also, I'm sure I can manually mold the shapes from a planar surface.  But is it  possible to trace the lines and cut a custom shape out?  That would save a ton of time.

[joojaa]

Assuming the plane is aperfect 1x1 square y being the plane normal you could do this (im being abit lazy you shouldnt do this much n maya overall):

proc jooCCRequestedSpherizeUnitPlane(string $planeName){
  float $kPi=3.14159265358979323846264;
  $points=`ls -fl {$planeName+".cv[ *]",$planeName+".vtx[ *]"}`;
  for ($point in $points){
    vector $pos=pointPosition("-local",$point);
    vector $rot=rot(<<1,0,0>> + $pos.y,<<0,0,1>>,$kPi*$pos.z);
    $rot=rot($rot,<<0,1,0>>,2*$kPi*$pos.x);
    move -ws ($rot.x) ($rot.y) ($rot.z) $point;
  }
 
}
 
 
// usage example:
jooCCRequestedSpherizeUnitPlane("pPlane1")

PS: merge the seam afterwards

[steve-j]

Thanks,  I'll give that a shot. 

[almakos]

cool script, Joojaa! works really well.
but is it different to make cuts on plane or on a sphere? no difference as for me )

using Split Polygon Tool + bevel + Joojaa's script

[joojaa]

Thanks. I was thinking is this sort of thing really so un-obvious? I mean its just a Cartesian to polar conevrsion (by the way the script actually also turns elevation into elevation in the sphere so anything at 0 y height will be at radius of 1 and anything at 0.5 y height will be at 1.5 units).

Now i was later thinking should this be extended?

see there's no real reason why one cant make a Cartesian to cylindrical, Cartesian to toroida, cartesian to hyperbolic Cartesian to Perlin noise an indeed reverses for fun effects. Or in fact any nurbs shape to any nurbs shape mapping of overlying polygonal shapes. But whats the real problem? Then it hit me, maybe the problem is.

Theres no name for this, at least not as far as artists are concerned. There's no tool in the menus for it, sure there are few tutorials on cylindrical modeling to do this. But this may not be obvious to everyone. Extending cylindrical to spherical may be too much.

So should a very general tutorial that shows how different mappings might make life easier? Realistically speaking one would need some good use cases for it tough.

but is it different to make cuts on plane or on a sphere?

Well yes if you approach it that way not really. It may be convenient since you see the whole work are in one go tough. However the script doesn't actually care whether or not it was a plane or not. So your shape could have been a planar of a vector outlines that's then turned into piece on sphere. (further it doenst care if they are polys or nurbs altough for nurbs it dont really work out if they are squares)

So what if instead of the grid you'd want to turn the grid into diamond shapes instead, on sphere it would be pain but on the 2d plane you could make a undivided plane and cut the plane into diamonds in no time. Then later fix the seam area or make the edges jaggy (they'd then fit the conversion again).

Anyway this could be made to use history so you could o back an forth between the shapes maybe several ones so you could cut in whatever space was easiest.

PS: theres several reasons why i think the script is no good in general, as it should be a node really. So yes i criticize my own actions too