Problems in smooth = Polygons

# 1 17-07-2008 , 01:40 PM

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Hi Guys,

need some help on the smooth process. I am making a car model which has a few inlets on the bonnet. I have extruded the faces and pushed them in for the shape. However, when I smoothen this, the rectangular shape converts to a hexagonal / octogonal shape. How do I ensure that the shape remains as a rectangle?

Thanks

GP

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# 2 17-07-2008 , 01:56 PM

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it is very easy to fix, any rectangles if you apply smooth on it it is turn to this hex-angles of shape, if you want to keep your rectangle edges smooth and the same shape you need make extra edges with polygon cut face tool, just create extra edges around your rectangle to keep the shape, later apply smooth on and see how looks like, hoop this help, otherwise i'll send you the image.

let me know if this helps,

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# 3 17-07-2008 , 02:09 PM

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The further apart the rows of edges or verts are, the rounder the shape will be when you smooth because the point at which the surface will bend or curve for smoothing to take place is halfway between two points. This is just what I've observed, maybe someone can give a more pro explanation :p

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# 4 17-07-2008 , 02:27 PM

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Yeah the closer your edge flow is the more it's keeps it shape.

Here is an illustration I made showing edge flow on a cube I modeled. Notice the lines are pretty close together.

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Last edited by THX1138; 17-07-2008 at 02:30 PM.

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# 5 17-07-2008 , 02:30 PM

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And here is the result after smoothing. As you can see the cube keeps it's shape. BTW I beveled the edges of the cube if your curious. Did it just for illustration purposes.

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# 6 17-07-2008 , 03:57 PM

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Hi,
I have tried the extra edges around the shape to keep it rectangular in the smooth mode. However, despite this, the shape deforms. The before and after image is as below. Not sure if I am right, but adding more lines to keep the shape on, would make the image heavy right? Also, do I need to have so may edges?

Thanks.

GP

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# 7 17-07-2008 , 03:58 PM

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This is the image before applying smooth.

Thx
GP

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# 8 17-07-2008 , 05:55 PM

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In time you'll get familiar with how this stuff works. And if you need the added geometry to get the shape you want no biggie, when you start adding more geometry when you really don't need it then you may want to rethink things, the less the machine has to deal with the better but the point is to get the desired look while being practical.

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# 9 17-07-2008 , 06:32 PM

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gputhige: Here is what the problem is. You don't have enough corner edges to keep your geometry from curving. Here is an example.

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# 10 17-07-2008 , 06:32 PM

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Here is a closer look at the inside.

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# 11 17-07-2008 , 06:34 PM

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Here is the smoothed version. As you can tell the geometry keeps it's shape.

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# 12 18-07-2008 , 07:53 AM

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Hi Guys,
thanks for the good feedback. This has helped very much though I still cant get the perfect rectangle I am looking for. Guess this comes with more practice. BTW, does hardening the edges first and then smooth help?

Thanks.

GP

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# 13 18-07-2008 , 07:59 AM

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Harding the edges? Could you be a little more specific?

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# 14 18-07-2008 , 08:12 AM

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Thats what you're supposed to do :p Add the edges to keep the corners tight then smooth, unless you want to get in there later and start sliding edges around. You have Maya 2008 so you can get a preview of the shape by hitting 3 on your keyboard without actually changing the geometry,(it doesn't render this way) hit 1 to get it back to low poly view.

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# 15 18-07-2008 , 08:19 AM

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Never heard the term hardening edges in place of keeping edge flow tight. Hardening and softening normals; yes, hardening edges, never heard of that term. learn something new every day. user added image

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Problems in smooth = Polygons

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