HELP: nGons and Triangles, how can you avoid them??

[EMKO]

yea i am wondering about this too from what i see people do is put triangles in spots that wont effect the mesh or make that part a new object but i am not to sure so i would also like a answer to this.

[Piflik]

For hard bodies you don't really have to care about tris, as long as you don't use any Sub-D algorithms. Non-flat n-gons can give you some weird results sometimes, but that holds true for non-flat quads, too.

In organic modeling, you also shouldn't try hard to avoid tris and n-gons during modeling, but concentrate on good edge-loops instead. You can get rid of tris and n-gons later.

This (http://maxrovat.sns.hu/subdiv/subdivmodeling.htm) might help.

[niic]

hey Piflik,



I'm quad modeling and using the smoothmesh preview in Maya2008. Here is a basic example of what my problem is or lack of understanding with modeling techniques rather, if you look at the screen capture on the left you will see the unedited version with a smooth on …as you can see the problem, with no supporting edges the hole in the roof is far too smooth and not realistic. If I however go in and start tightening up the geometry around the hole you can see the mass amount of additional resolution created in areas where there really doesn't need to be anything. My actual project is 10x more detailed than this but you get the idea …my floor and walls become so heavily populated with unnecessary detail I’m losing my mind trying to keep it all clean. I can’t extract the peace because I need the resolution around the hole to make it realistic where the window would sit. It is dealing with this additional detail and how to terminate the resolution is where I'm having major issues. My actual model has three windows and also detail on the walls so my floor is a complete mess of mesh with triangles and nGons all over the place! In this example there are only quads since I’m not attempting to terminate any edge loops anywhere.



This creates a further problem because what if I wanted to now go in and add a window on one of my walls, I now have to try and deal with an insane amount of geometry to get what I want.



I put the Maya file up there as well if you are bored and want to take a look at the mesh (it is 2008).



I know I’m missing something.



Image: http://www.vividpixel.net/pub/maya/geo_res.jpg (http://www.vividpixel.net/pub/maya/geo_res.jpg)

MB: http://www.vividpixel.net/pub/maya/creating_resolution.mb (http://www.vividpixel.net/pub/maya/creating_resolution.mb)



Any suggestions on technique would be really great.



Cheers,

Nick.

[Piflik]

Sorry, I am using Max, but if you have an obj, I can have a look at it.

In the meantime you can try something like in the image attached. (It shows one corner of the window.) That should reduce the density without creating much pinching.

[niic]

Hey Piflik,

http://www.vividpixel.net/pub/maya/WindowSubDedges_loops.jpg

Re your example image... what do you do with the edge loops you have around your? I have circled the ones I mean in green. If those edges were ajoinging walls and not simply the end of the mesh what then? With my current understanding I would have to run those all the way around the mesh. There is no point having that resolution running through the floor or adjacent walls so I'm wondering how actually would you terminate those loops so you don't have irrelevant resolution where it isn't needed and create the issues with pinching etc??

http://www.vividpixel.net/pub/maya/WindowSubDedges_loops.jpg

Really appreciate the help mate. Thank you!

Cheers mate,
Nick.

[JasonA]

....what do you do with the edge loops you have around your? I have circled the ones I mean in green. If those edges were ajoinging walls and not simply the end of the mesh what then?

The way that Piflik drew them out is the solution. You cant easily get around having at least one vertical and horizontal loop coming out corner of a cutout. The way he drew the changes shows how you can make a tight corner without adding even more edges to support. There are other topology methods you can use to create a sharp corner too, but I've used Piflik's layout numerous times.

With my current understanding I would have to run those all the way around the mesh. There is no point having that resolution running through the floor or adjacent walls so I'm wondering how actually would you terminate those loops so you don't have irrelevant resolution where it isn't needed and create the issues with pinching etc??

How you resolve loops depends totally on the topology of the mesh, not only in its current state, but in its future state. In other words, what I have found is that as you add detail geometry in other areas of the model, those areas will also require support loops. You can quickly find that loops you didnt know how to terminate earlier all of a sudden can be used to run into your 'other' detail area, hence solving the looping issues. So sometimes its just easiest to not worry about it this very second, and add in detail elsewhere. sometimes these problems solve themselves

[niic]

hey Jason... yep I'm with you and figured as much! I'm just wanting to make sure im doing things correctly and my mesh is clean and optimised! I would like to eventually make this a career one day.

Thanks Piflik, most helpfull mate!

cheers

[shroomer]

edit: ignore this. i read the post wrong... apologies

[niic]

Hey Shroomer,

Thanks for replying though - I got your actual post via email ...appreciate the effort anyway!

Cheers

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