How to reduce number of polygon without breaking form?

alex_kim

Hello, people.

I am trying to create a simple missile launcher which is cube shape.

Reference: 



As you see, it has a lot of holes that will generate a lot of edges. 


This is what I did so far. since I create holes for missile (blue cylinder), the entire box has extra edges and faces.

Is there any methods or skill to reduce those edges? Please?

Thanks.

Larry

@alex_kim
i think you are missing the idea... the "low poly" model is probably not the same model you need when you subdivide/smooth it.
I did a quick paint over the half of your model to show how many less polygons you can save. You could save even further, but it can be too complex to draw in photoshop. I hope you get the idea.

Also reduce the cylinder sides. 24 is way too much for a cylinder for a low poly. They can be 16 sided and still have a very good round quality. Also delete the cylinder polygons that look on the inside 

Zack Maxwell

In addition to what @Larry said, most things that do not influence the silhouette can be baked into the normal. This definitely includes that bevel you have running around the border of the front face; it would look virtually identical whether you actually modeled it into the lowpoly or just baked it into the normal.
Assuming you were to add a bit of a slope to it.

Larry

Zack Maxwell said:

In addition to what @Larry said, most things that do not influence the silhouette can be baked into the normal. This definitely includes that bevel you have running around the border of the front face; it would look virtually identical whether you actually modeled it into the lowpoly or just baked it into the normal.
Assuming you were to add a bit of a slope to it.

Hey @Zack Maxwell indeed you can bake that as well however from what i've noticed in the games i've played (after learning about 3d) they all seem to keep those kind of shapes, crevices, and bevels in every object so my guess is, modern hardware is so advanced that you can afford keeping them. Also i believe this kind of crevice alex has, would be badly visible from up close if you were to bake it, since it's quite deep

alex_kim

Hello, people.

I fixed it.

Back:


Front:


As Larry suggested, I reduced the number of side faces from 20 to 16 

Larry

1st picture:
Delete red lines, move green to where they point
2nd picture:
Red lines: you forgot to add them
green lines: move to where they point
blue lines: delete these polygons you dont need them if you put missiles there

Zack Maxwell

I don't know about moving those green ones, at least in the first image. The effect on the overall polycount would be trivial, but creating such long and poorly angled triangles could cause shading errors.

Larry

Zack Maxwell said:

I don't know about moving those green ones, at least in the first image. The effect on the overall polycount would be trivial, but creating such long and poorly angled triangles could cause shading errors.

Well yes, i did it kind of hastily and forgot that they would mostly stretch the polygons in the cylinders. Fixed it to a point where they won't show anything. Going for mobile games might require this kind of reducing i guess.`There are many polygons in his model which serve no purpose

alex_kim

I fix more :-)

Eric Chadwick

If missiles are going to be in those holes, then you don't need the holes behind them.

Mark Dygert

If the missiles are static and never disappear, the holes aren't needed.
If they ever fire and it's important to see the indent, then you'll want them there.

Missile tubes are typically hallow, or capped with break away pieces so exhaust isn't trapped in a confined space, destroying the missile before it gets out of the tube.

So there are a few design decisions that have been taken into account and could cause some headaches later.

I think the number of sides could be reduced even more. They have more sides than the rounded corner details, you need to try and maintain a consistent level of poly detail across the model. Having ultra rounded cylinders next to blocky rounded corners, looks inconsistent and sloppy. 

A lot of work has gone into getting the hole geometry to flow into the surrounding area, which might be making things more complicated than it needs to be. If you separate the geometry you'll have better edge control. 


You can swap out the cylinders fairly easily, if you need different shapes.
For lower LOD's you can remove the cylinder meshes all together.

Also don't forget about chamfering verts to make holes.

1 Chamfer = 4 sided, 2 Chamfers = 8 sided and so on...

alex_kim

Hello, Eric and Mark.

Thanks for your tips. And, Mark's tutorial video is so great :-)

About the missile hole, some of them will be filled with missile while others are empty. 

This is my reference (I am not going to make it exactly same though):




And, this is what I've made so far



Red area is where I put the missile launcher with missiles.
Purple area is where I put the grenade container.

Green area is where I plan to put the workbench or something like it. So, I can put some weapons to make intensive mood. 



This is one of weapon I will put on the green area :-)

Creo_metus

Mark Dygert,
I never even thought to chamfer verts to make a hole... That's brilliant . I appreciate that tip as well.