Hi,

I am having a problem with orienting objects in CSG's. Due to my poor
math skills I can't seem to figure it out.

I want to use one cube to cut another cube using a difference CSG.
Sort of like making a pyramid by cutting a cube. However, unlike a
pyramid the cutting cube I want to use is not square to any axis.
Since I am trying to model something specific using the CSG I would
like to position the cutting cube precisely.

I know the coordinates of three points on the cube to be cut which I
want to hit with the cutting cube. Does anyone know a procedure to
determine from these points the rotation angles (x,y,z) I need to
place the cutting object where I want it?

Right now I have to use trial and error and lots of renderings to get
the results I want by making slight tweaks to the rotations. Perhaps
there is a better way?

Thanks for any help,


Stefan

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Hi sso### [at] aolcom, you recently wrote in moray.win:

> I want to use one cube to cut another cube using a difference CSG.
I'm not sure I understand what shape you want to make, but some things
that may make life easier are:

- Use the local coordinates function to move the pivot point of the
cutting cube to a face. That may make it easier to position.

- Use more than one cube, for example one cube for each plane that you
want to cut away.

- If you know the coordinates of all the points of the final shape,
write a small POV include file and the corresponding UDO and use that.

Regards,

- Lutz
  email : lut### [at] stmuccom
  Web   : http://www.stmuc.com/moray

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Lutz,

Thanks. That helps some, but it is still trial and error.

I have used UDO's in the past by generating the object using a cad
program and importing it in to Moray. However, when you cut a UDO the
light which comes in the hole is visible on the outside of the object.

The picture attached shows a UDO object both with and without a hole
in the far side. As you can see there is a bright patch on the near
side from the light coming through the hole.

I am trying to make the object in the picture using CSG, but figuring
the angles to cut the tapered ends is difficult.

Stefan

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