Hi Will also one other note:
quote:
Now I did perform a test yesterday, exporting two joined surfaces into Cinema 4D - all the normals were in the proper direction, but the app I really need to test is Lightwave since that's the one that exhibited the flips the last time I ran across the issue.
Also when you join pieces together, what it will do is give you a _consistent_ normal between each piece.
However, unless it has joined all together into a solid, it is possible that the whole piece may not have the normal direction that you want.
That's something that happen in any 3D app where you are not working with closed objects, including polygon modelers as well - it's why there is a flip function in all polygon modeling programs.
If you have everything closed up into a solid, then again one of those convenience features kicks in and MoI will know how to automatically orient things to the "outside" of the solid. But if you do not have a solid MoI (and any other 3D program really, including NURBS and polygons as well) does not have any good way to know which side is supposed to be the outside.
So if you work with open objects in MoI instead of solids, you may need to flip your object at some point, either in MoI (set up a keyboard shortcut and put in Flip as the command name), or more likely in your polygon modeling program where the normals have become important to you.
But again that is not something specific to MoI - any 3D modeling program that works with open objects may require flipping at some point because it is not generally easy for software algorithms to recognize which side of an open mesh is supposed to be the "outside" part, since there is only a clearly mathematically defined inside and outside with closed objects. Without it being clearly defined, it tends to require human judgment to say which way they are supposed to go and it is difficult to emulate human judgment in software.
But Joining will still help you significantly because it will make the whole joined piece at least have a consistent normal throughout it, so that individual sub-pieces of the joined object do not need to be flipped independently, just the whole thing may need flipping still.
The only way you can avoid the need to potentially do any flipping at all though is to make solids before exporting the mesh - that's the case where it is handled for you automatically.
- Michael
