Combine Polygons

T

tpitman

0
Combine Polygons

I would like a quick tutorial on how to combine polygons. I have a simple OBJ file that has a lot of polygons that are not needed.

I know I could get a decimation app, but they tend to mess up the polygons.

The model is simple enough that I think if I could select a bunch of polygons on some of the large flat surfaces and then simply combine them that would reduce the poly count enough for what I need.

I can see how to divide polygons, but not how to combine them.
 
That isn´t as trivial as it may sound. When the polycount is a result of a subdivision some apps can rebuild the former stage. If it´s just the end of a poly-by-poly modeling process you have to do it by hand and will destroy the UV-layout of course - if there´s any. You can try to delete edge-loops carefully for example or use target-weld. Optimize-tool is an option as well but will produce tris for sure. But this advice is a bit dangerous without any screenshot or the model itself.

Cheers
Frank
 
This is just a very high poly dice model I got on a free model site.

I have several very flat surfaces on the dice that have tons of polygons that don't need to be there.

So lets say I have this flat surface with 10 x 10 polygons (4 vertices per polygon, so not triangles, but I don't care if they get turned into triangles).

If I want to take those 10 x 10 polygons and turn it into a single polygon, how would I do that? Just reduce it from bing 100 polygons to being a single polygon that takes up the same space?

Hopefully this image will share:

https://drive.google.com/open?id=0B3P6IntD-KkaVW8xeERqVjhtc2c

That shows the middle of one side of the dice. The surface is virtually flat, so if I could just combine a whole bunch of those polygons that would be great.

I will probably do it iteratively, so instructions on how to select some polygons and then make them into a single polygon and then select that same polygon and select some more along with it and combine those would be great.
 
The easiest way in this case is to select all the polygons you don´t need and delete them - then take the create polygon tool and in point mode recreate one single quad by connecting the four corner points - then go optimize to get rid of the unconnected points.

Cheers
Frank

PS: added image
 

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:smile: It’s late for old granny but I have an idea.

This is pretty rough and I’m too tired to play with it any longer.
The General idea is to use a Box & a Ball & a Boolean Modifier.

I forgot the dimensions of the ball I used but I think it was default
and I used 16 sections longitudinal and 16 sections parallel.

I don’t know if I even used the boolean correctly.
Maybe if you play with the size of the box & ball you can get it to your desired shape.

My Best Regards
Jeanny
 

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Also, once I get the basic shape done I need another thing I can't figure out easily.

That is the flat surfaces need to be divided. I know how to do a linear or catmull divide.

The problem is that I need the division to end up being 9 sections instead of 4. Basically it needs to divide into 3rds.

The reason is because the next step is to make the dots on the faces of the dice. If I do a regular divide it divides in 4ths.

I know I could manually draw new lines, but then how to I line them up as exactly as possible and then duplicate the exact same on all 6 faces?

Suggestions?
 
When you adjust the iterations of the box&scale on the fly you can have 3x3 equal quads on each side:
DiceBoolean.png

Cheers
Frank
 
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I should have thoughts of that. I will do that.

I have another small problem with the boolean. I know this is beta, so if this is something you are working on then I understand.

Here is the dice after the boolean of the ball and box. Note that I have tried many iterations of the number of sections for the ball and they all give the problem, just bigger or smaller.

This is a screen shot in Cheetah3d:

https://drive.google.com/open?id=0B3P6IntD-KkaeWRMOF9MZ0pSRDA

When I bring the model into Unity you can see the dice apparently casting shadows on itself because the polygons I guess are not uniform.

Here is the model brought into Unity:

https://drive.google.com/open?id=0B3P6IntD-KkaM2NHWkEyclNJcEE

Is there a way to fix this? I need the lighting in Unity...
 
Actually I just need to divide up the box before doing the boolean. That keeps the distortions to the intersecting edges.

I will play around with it.

This is really awesome and a great learning experience. Thank you for such a great tool!

Well worth the money spent.
 
Because of what those 2 screen shots showed.

When I tried to do low poly the edges between the ball and box give weird shadows in Unity.

I am now trying to recombine the polys on the sides of the dice.

Is there a better way?
 
Low poly gives me this:

open


I guess I am looking for a good balance between poly count and not having all the weird shadows.

The good news is even what I have now with the higher polygons is way less than the model I have which has almost 200k polygons.
 
BTW, how are you guys embedding your images into your forum posts?

I am having to create a PNG, upload it to my google drive and share the link and even then it doesn't show up like yours do.
 
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