Geometry count, a real issue.

[Cool_Z 1,547]

I noticed two things.

 

First, I can import a building in the game without even making a LOD for it, means that the game uses all the geometry when zooming out.

 

Second, that some builders use an incredible amount of geometry... I just saw someone posting a quite simple high density residence with 2700 tris.

 

There seems to be no limit to what the game acccepts to import, I hope people realize that staying low poly saves gpu power and makes the game run smoother. I won't install things with a ridiculous amount of geometry.

[neona 0]

First, I can import a building in the game without even making a LOD for it, means that the game uses all the geometry when zooming out.

Actually, the game will just generate a  (very bad looking) LOD in this case.

 

I do otherwise agree that it's easy for poly counts to get out of control, though - perhaps some community guidelines should be created to help give people a better idea for target poly counts/etc.

[Cool_Z 1,547]

Actually, the game will just generate a  (very bad looking) LOD in this case.

 

I do otherwise agree that it's easy for poly counts to get out of control, though - perhaps some community guidelines should be created to help give people a better idea for target poly counts/etc.

 

 

Ok I feel better about the LOD now...

 

Agreed on the guidelines. We should add the uvmaps size too because I already convinced a guy to go down from 2048 to 1024 on a building. (8,5 to 3 Mb file in the end... quite a difference.).

[Hamish 1,369]

 

 

...perhaps some community guidelines should be created to help give people a better idea for target poly counts/etc.

 

 

I agree too. Not sure when it would be appropriate to introduce this. Probably after a few months of moding and exploring the buildings in the game will we reach a poly count guideline, but its a very good idea to start thinking about it now. Keeping poly counts low is a must for a most custom content.

[Cool_Z 1,547]

 

 

 

...perhaps some community guidelines should be created to help give people a better idea for target poly counts/etc.

 

 

I agree too. Not sure when it would be appropriate to introduce this. Probably after a few months of moding and exploring the buildings in the game will we reach a poly count guideline, but its a very good idea to start thinking about it now. Keeping poly counts low is a must for a most custom content.

 

 

I think about it more like an emergency measure to take, because right now hundreds of people have already started building stuff (and some are already downloading dog kennels with 3000 polys and 2048 uvmaps).

[T Wrecks 10,209]

No recommendations from the developers of the game? Or is there a way to check the typical polygon count of default buildings?

[Cool_Z 1,547]

No recommendations from the developers of the game? Or is there a way to check the typical polygon count of default buildings?

 

There were some recommendations, but the paradox forums are quite a mess now... They're buried somewhere.

 

Edit : Found this about poly count :

 

 

Some more details about LOD's and poly counts from Henkka:

"Start with ~1000 triangles for buildings (can be fewer triangles if smaller building like a detached house - the fewer the better performance-wise), going up to 10K+ triangles for really big, monument sized buildings but don't go too far over 10K tris. LOD models need to be as few triangles as possible, maximum of 100. Keeping it below 100 tris guarantees it actually works. LOD model does not need to be textured but it needs to be UV-mapped. LOD filename should end with "LOD.fbx".

 

http://forum.paradoxplaza.com/forum/showthread.php?840333-Custom-Building-Competition

[Cool_Z 1,547]

I've just seen that guy from Maxis buildings have a big poly count...

 

[Cyclone Boom 16,875]

If Colossal Order could confirm some recommendations, that'd be a great starting point.

 

Then I think it'd be neat if there was a tool, able to find the poly count for any building. That way, anyone could test if a custom model is likely to slow down the game, in proportion to others / the recommend value. Especially if downloading building collections from the workshop, I think this would be a useful way to validate them prior to using. The last thing anyone wants is to install a bunch of buildings, notice the game runs slower, then have to track down the culprit(s).

 

E.g. Some useful features may include a batch checker mode, and a way to "flag" models with an excessive count.

[JaWood 194]

Well, I've been modeling my first building for C:SL and here are some of the things I've been noticing as I've been going along.

 

The building I'm creating is a small car wash facility on a 3x3 lot called the Super Suds.  I'm going for a kind of stylized look with fun shapes and colors. Remember these downloadable buildings from Maxis for SC4 back in the day?

 

http://www.wiki.sc4devotion.com/index.php?title=Sobchak_Lanes_%28DLC%29

http://www.wiki.sc4devotion.com/index.php?title=Lucky%27s_Hang_Ten

Shorty Burger (Can't find a link to it.)

 

I'm kind of going for a fun stylized, kind of retro feel while using those lots as inspiration. So my building has a car wash tunnel, the a central office attached to the side, a vacuuming area, storage tanks on the side of the tunnel holding soap/wax (more for a fun visual appeal than for realism), and a big tall stylized neon sign next to the street.  There's swooping arced roofs with v-shaped posts supporting some of them where they overhang the building, and curbing to show how traffic is to flow through the lot. Sorry I don't have pictures. I'm not ready to show it off and I'm away from my main computer anyways.

 

Now here's the thing. I'm almost, but still not quite done with the modeling portion of this building. My poly count is probably 2000-2500 triangles at the moment. I am aware of Paradox Forum's suggestion to stay at or below 1000, but I just can't seem to get anywhere near that level. I've made sure the arched roofs are low poly, and have reduced their number of faces a couple times during modeling. I've kept all pole, pipe and post diameters at 6 sides or less. Some modeled details are one dimensional only. The building doesn't have a bottom since you won't see it.

 

In desperation, I loaded the Asset Editor and started studying the in-game buildings that are roughly the same size as my car wash. I don't have a way to gather their exact poly count, but I can't believe most of them are holding to the 1000 or less rule. There's just no way!  Some simple houses have fully modeled railings going around the building with 3D rails and rungs, fully modeled rain gutters, fully modeled window frames, some with 3D trim and inset window jambs, some have arced features, and the list goes on. They're not any less detailed than what I'm modeling, that's for sure.

 

And here's the other thing. I read somewhere that our models need to be one continuous connected shell with no intersecting faces. So whenever I have something like a vent coming out of the roof, I cut a hole in the roof where the vent meets and connect the edges together. This majorly breaks up the triangle count for the roof, or wherever else I weld stuff together like that, but It's what I read to do and it's supposedly the correct way to model for S:CL. If I could model the building in sections and group the sections only to themselves, like make each roof section their own groups, the building sections their own groups, the overhang supports their own groups, etc, and they don't weld to each other, then The poly count would be waaaay lower.

 

I don't know what to do other than ignore the 1000 triangle rule and just keep going while still trying to be as conservative as possible while still maintaining a descent amount of detail.

[Cool_Z 1,547]

I agree that it will be difficult to stay around 1000... and it's more like "try to stay there if you can" but the fewer the better.

 

Even if some of OC's buildings are obviously over 1000 it still takes more to render hi poly than low poly... and most of us will download everything that's available to the point CO buildings will be a minority.

 

 

I didn't read anything about the non intersecting faces. 

[JaWood 194]

Well if I can get away with intersecting geometry, then I will. I haven't tried importing it both ways yet. I guess I ought to.

[iviaarten 533]

Well if I can get away with intersecting geometry, then I will. I haven't tried importing it both ways yet. I guess I ought to.

I think I read it has to be a single object.

[xonedl 341]

Well, multiple entities under one group is still one object.... perhaps.

Someone wanna test it out? Merging everything is a very very very bad idea - the polygon count can go up like crazy...

[JaWood 194]

Well, multiple entities under one group is still one object.... perhaps.

Someone wanna test it out? Merging everything is a very very very bad idea - the polygon count can go up like crazy...

The frustrating thing is Sketchup (what I like to use for modeling) merges and welds geometry together by default. I can get around it by creating portions separately out in open space, grouping the faces together, then bring all the groups together to assemble the full model. A little more time consuming, but way fewer polygons.

[xonedl 341]

 

Well, multiple entities under one group is still one object.... perhaps.

Someone wanna test it out? Merging everything is a very very very bad idea - the polygon count can go up like crazy...

The frustrating thing is Sketchup (what I like to use for modeling) merges and welds geometry together by default. I can get around it by creating portions separately out in open space, grouping the faces together, then bring all the groups together to assemble the full model. A little more time consuming, but way fewer polygons.

 

 

Uh...... you should be using grouping all the time, why you need to move things around?

Create a wall - group. Create a floor - group, Ceiling, group. Roof, group.... If I gonna use the same item twice, turn it into component. You get the idea.

It probably the most used context function around whenever I drawing things.

Triple click > Right click > Make Group has become a process that I'm not even aware of the "tediousness" after all these years lol...

 

I'm not proficient in other 3d softwares but what I see is, they are already pre-grouped for you whenever you create a basic object.

However we don't create basic object in Sketchup, rather we start with face / line.

[Mr_Maison 2,426]

Does CS support models done with quads? Working with quads instead of triangles would not only make cleaner models but reduce ploy counts also. I will also add that using groups and components in Sketchup is essential unless it's a very simple object.

[bixel 1,223]

http://gamedev.stackexchange.com/questions/66312/quads-vs-triangles

 

Personally I am still learning the UV-unwrap stuff, cause texturing for these models is very very hard compared to SC4. But I will be releasing some buildings pushing 4000. There are many tricks to keep detail while removing polys.

So my recommendations;

 

1 Cull faces not visible by camera, and all 'under' faces.. even if you like to go FPS mode.

2 Replace fence model or balcony model with a texture with alpha channel.

3 Trim excess detail even though this is artistically painful... 

4 Examine parts of the model where a surface could be remodel cleaner

[Cool_Z 1,547]

...I will be releasing some buildings pushing 4000...

 

"I will be releasing some buildings"... "I will be releasing some buildings"...                 

[Jasoncw 11,840]

It's a hard thing to balance because their recommendations are for making the game run smoothly under certain computer specs. I don't know what those are, but presumably they're targeted towards the average gamer's computer, and many of us here will have better computers than that. The other thing is that computers get better over time, and I think it would be good to have more resource intensive buildings now, but which will last longer, than have a bunch of buildings now that will look terrible and need to be replaced in 5 years. But this still means being aware and respectful of polycounts and texture sizes. We need to be very lean and responsible about these things. Higher poly but sensibly modeled things are what we want, and 4,000 poly dog kennels are what we need to avoid.  

 

I think they key to making excellent buildings that are not resources intensive is very careful building selection.

 

Some buildings, by their nature, require fewer polygons to accurately model. This means you can either splurge on isolated areas that would benefit from it, or you could have the entire building be lower poly to accommodate other buildings where inherently require more polygons. Or maybe if the building is really low poly you can afford to have a higher resolution texture.

 

For textures it's similar. Some buildings don't have as much surface texture, or they have a lot of texture repetition, so you can get away with lower resolutions. Also, the texture space is not linked to geometry size, so if you want one area to have higher resolution textures you can, at the expense of the resolution of other parts of the building.

[Shy Dude 149]

I think people are underestimating the power of normal maps. The only problem I see is doing a building with tons of sculptures or columns but stuff like pilasters and windows doesn't seem troubling.

[Cool_Z 1,547]

It's a matter of knowing what you want to do in certain areas... and what is acceptable or not.

 

One stupidly simple example might be a house I haven't finished yet.

 

I wanted to add a store on a window. It was an easy addition... but I had to add the stores supports. I could use only two triangles but add an alpha to cut into them and create bars... or two more triangles to make the bars solid and no alpha map for the whole house.

 

It's all a question of balance.

[Ocram's Razr 963]

It would be great if Cities: Skylines used more than 2 models for Level of Detail. I think Cities XL was optimum with 4 LOD levels and 4 tiers with the lowest LOD having a limit of 100 triangles and the highest T4 (exceptional building) L1 (highest resolution) model having a limit of I think 20,000 triangles. More levels of detail mean that performance and visual quality can both increase (at the expense of having a bigger file size).

--Ocram