Quad modeling help

[yuri_ch]

Hi! Who knows where to find some nice tutorials explaining how to work with quads? I saw some of them with Aaron but look here as my example and I’d like for example to make a rectangular hole in a cylinder. Think I did a right topology and every polygon is a quad. Then I use Artisan to subdiv my shape but tris appears and it gets not a rectangular form. So the question is why am I getting such a result? I know I can use another software tutorials (3ds max, Blender, Maya, etc.) to study working with quads because the principles are the same and I do it but looks like I’ve missed some basic things to continue studying quad topology.
I’ve attached an example in skp.

quad test.skp (5.9 MB)

I can control the rectangular form with the help of some additional edges over the hole and it do something similiar to what I want but then the edge in the top of cylinder gets sharped form because of this extra edges I draw. Some kind of vicious circle

[yuri_ch]

I know about crease tool in Artisan but it makes edges fully sharped. The way to control roundness of the edges is to add supported edges as in my last screenshots but as you see it causes another problems with the shape. So what I’m doing wrong?

[Cotty]

Artisan does not take into account quads, so you should use SubD in this case to keep the quad topology.

[yuri_ch]

thanks. just bought subd and see it works as it must and here is crease tool which can control the value of creasing.