Celestia Forums

I have encountered a really basic problem in Anim8or which I'm not sure is due to my own mistake or maybe a bug in Anim8or.

Can any modelling/Anim8or experts help me?

I'm trying to make a hemisphere and it appears that in the process of cutting a sphere in 2, parts of the remaining mesh are distorted (stretched) from where they should be. It appears that after removing points from the sphere, the remaining hemisphere is distorted and is a little bit bigger at the cut edges (It seems to be stretched at the equator)

I suspect that the most likely explanation is that I'm using the wrong technique to cut a sphere in half. This IMO should be really simple, but I'm at a loss as to exactly what I've done wrong. HELP!!!
(NOTE: I've done this before with success, but I can't remember what I did differently)

These are the steps I'm taking...

1. Create a sphere (72 long and 72 lat divisions):



2. Convert to subdivided:



3. Rotate X-90:



4. Select "Points" mode:



5. Select the right half for deletion (points):



That leaves me with:



6. Leave "points" mode:



I created another sphere using the same steps as above...



...and then positioned it in the same position as the hemisphere to demonstrate the difference between the two. (NOTE: the highlighted band around the equator where the hemisphere surface is higher than the sphere:



A closer look (with sphere selected):

You really need to ask this kind of question at the Anim8or Forum.

My guess is that it's because it's subdivided.
Just say no to subdivision. i.e. try cutting it before the conversion.

Also, don't forget that large numbers of triangles will cause a substantial loss in 3D performance. Appropriate surface normals can be used to hide the use of a limited number of vertices in the model.