Render trick with spheres

[TomD.inPDX]

This is a Creo 2.0 M040 part. There is no reason to believe this will work on future releases as it is likely a bug.

But... for the meantime, I found a way to change the color of half a sphere with basic Creo render. If you ever -tried- to do this you know what a pain it can be.

The idea is that the color is applied with the sphere only revolved half way 'round. Change the color of the solid body and then apply a different color to the hemisphere. Then change the revolve to 360 degrees. Whallah!... you now have two appearances on a contiguous spherical surface.

Video Link : 3913

[DaltonF.]

Mirror works too. Revolve 180 degrees, assign a color to the solid body, then a color to the hemisphere. Mirror that across the sketch plane you used, and it looks exactly the same as the way you showed in the video (just in case future releases fix this, if it is a bug).

[TomD.inPDX]

That's good to know; Thanks!

[gkoch]

I believe this is because Creo is trying to impose, that the full revolve is only one surface (while the internal mathematics always need two, to close the surface). So when you select one of the two half surfaces and apply the color, it gets applied to the other as well by Creo.

As it seems this little "fake" has not been implemented to deal with mirror or redefinition of partial revolves. I agree, that it could happen to be "fixed" some day (although I assume chances are low as is the priority).

Even Editing > Split Surface (with the option to select contours automatically) creates a "similar instable situation", i.e. it applies the original color to the second side, but when you try to apply a different color to either half, the full surface gets colored again.

[DaltonF.]

If all else fails, Creo allows a negative revolve angle value to be entered. (-180 becomes 180, but when checking out, it revolves in the opposite direction), so assigning a color to the entire part, then a +180 degree revolve, color, -180 degree revolve, and you have a bi-colored sphere. It merges the two surfaces, however, so repainting one at a time doesn't work still.

[TomD.inPDX]

It really is a fluke. I can see someone complaining about the behavour but for me, it is a nice bug to have. We have so few -nice- bugs