View Full Version : Cutting a circle inside a four-sided poly

10 October 2010, 09:58 PM
What would be the best way to go about inserting a circular shape into a four sided poly?
In this instance I am designing a robot and I need to insert an 'eye' on the front panel of the robots body. The main body of the robot is essentially a tapered cuboid, not an actual 'face' (to avoid any confusion) This main body will then be supported by legs and so on.

Currently the front panel is a single four sided poly. The circle needs to be inserted in the centre. This shape can then be extruded to create a socket for a sphere to sit in.

The obvious way seems to be use a boolean subtraction using a sphere to cut the socket out of the poly, but it will result in weird results due to the difference in vertices/edges etc. I would imagine some works needs to be done clean up the edge flow.

Any suggestions?

PS: I attached a reference image (WIP but you get the basic idea of what I'm asking)

10 October 2010, 02:36 AM
Hey CJ.

This link should be of some help to you especially if you are using 3ds Max. About half way into the vid Grant talks about what he does when a curved surface needs a circular extrusion.

***video link**** (

Unless the surface is completely flat you will have to fiddle around with the verts no matter what method you use.

If you are a Maya user like me, I just bring in a 6 or 8 sided cylinder and try to match up my verts to the cylinders edges and than clean things up when its all said and done.

Hope that helped.


10 October 2010, 04:30 AM
heres what i do:

line up the cylinder with the plane > boolean the plane with the cylinder > add edgeloops to the designated areas > voila

10 October 2010, 02:22 PM
thanks for the help. That boolean method works great :applause:

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10 October 2010, 02:22 PM
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