Trees, Poloygons and File Size

[Mr_Maison 2,426]

Posted this over at Paradox but wanted it to get more exposure here.

I am making some trees and find they are very high in polygon count. Too big in my opinion. I'm seeing 32mb so far. I don't plan on spraying the map with them but just to make some special trees for certain areas. I want to be careful how big I make them.

Some questions:
1. Does the game treat trees as instanced objects or duplicates?
2. What is the average size of the in game trees in terms of mb and polygon count?
3. What should be the highest file size for a tree?

 

My system can handle big files i7-3940k, GTX 760 2GB, 16GB RAM. Just worried about what it would do to the game performance if I plopped a few heavy trees in there. But at the same time I would like to publish some of them also.

[wallacet 336]

Enter Shroomblaze.....

[Mr_Maison 2,426]

Enter Shroomblaze.....

Yeah, I been following him. So far he helped me with foliage color. I'm making heavier trees in a style different from what's in game. I'm sure he'll be along in here soon.

[Mr_Maison 2,426]

This tree is a monster at over 2000 faces. But I want to see it in my map. I'll let y'all know how it goes later when I finish UV mapping the leaves. Have a feeling some pruning is in order.

 

But to put it in perspective, for what I normally do in 3D this is much lower than average.

[Dubai Skyscraper 129]

What I don't understand is how you reached such a "high" poly-count with such a simple tree. I would be really interested in the wire frame view, could you upload a screenshot?

Apart from that, I guess the best way to find an acceptable, average poly-count is by try and error. Just spam the tree until you can notice significant fps drops

[Mr_Maison 2,426]

The tree imported with no problem at all!   The FBX is only 110kb, texture is 4mb and can be reduced. (I have no FBX tech knowledge so don't know what that have to do with poly count in 3D apps) The tree sways and everything without a problem. Don't feel heavy in game at all. I think I read somewhere that buildings can go up to 10,000 polygons(don't quote me on this!). 2000 polygons for any quality tree is very small. As it is good to work at the most optimal levels, we cannot be too afraid of the count for certain things. For the branches I went as low as I could go for the form before they would turn to octagons. The leaves are billboards. They look more dense than they really are. As I said earlier, I don't plan on making a whole forest out of trees like this. I just want some more realistic trees in some key spots of my landscapes especially parks and yards of homes and businesses. This tree was made with XFrog and processed in Blender for UV unwrapping and FBX export.

 

 

 

 

 

BTW Dubai Skyscraper-XFrog is know for making very high poly trees. It's a fight with this program to get low but it's the best I have right now. Wish I could afford SpeedTree.

[TPB 563]

Yeah I imported a 1440 tris bamboo plant and seems to work just fine. As long as you don't go crazy and plant 250k of them I don't see a problem : )

[Shroomblaze 320]

I personally try to keep my trees below 600 Tri's for the sake of game speed. If someone happens to plop down 250k trees with 2000 Tri's it may be game intensive. Ideally I have kept my trees around 300 Tri's though.

[Mr_Maison 2,426]

Does anyone know where all the files size goes when making an FBX file? In Blender this tree was reporting 2500 and 32.98mb. The FBX is 110kb. What happened? Is there still an elephant in the room?

 

I personally try to keep my trees below 600 Tri's for the sake of game speed. If someone happens to plop down 250k trees with 2000 Tri's it may be game intensive. Ideally I have kept my trees around 300 Tri's though.

Shroomblaze, I think it would be near impossible to get a tree like this at 600 tris.

 

 

 

Yeah I imported a 1440 tris bamboo plant and seems to work just fine. As long as you don't go crazy and plant 250k of them I don't see a problem : )

I'm thinking of a very low poly tree design for forestry. Would love to see your bamboo tree.

[TPB 563]

I'm thinking of a very low poly tree design for forestry. Would love to see your bamboo tree.

 

It's on STEX :>

 

By the way I didn't make the model so it's not technically *mine*

 

I found it on DA and the creator allowed me to use it.

 

I'm trying to learn atm so I can hopefully make these myself soon.

[Shelltoe 15]

Does anyone know where all the files size goes when making an FBX file? In Blender this tree was reporting 2500 and 32.98mb. The FBX is 110kb. What happened? Is there still an elephant in the room?

 

 

yes the elephant is still there. the fbx contains only numbers and coordinates. all the other stuff blender saves in it's .blend files isn't needed. like textures, animations or fluid simulation data etc etc

 

actually most of the stuff inside the fbx isnt needed aswell only the raw mesh data.

 

afaik blender creates smaller project files than most studio solutions.

[Mr_Maison 2,426]

 

Does anyone know where all the files size goes when making an FBX file? In Blender this tree was reporting 2500 and 32.98mb. The FBX is 110kb. What happened? Is there still an elephant in the room?

 

 

yes the elephant is still there. the fbx contains only numbers and coordinates. all the other stuff blender saves in it's .blend files isn't needed. like textures, animations or fluid simulation data etc etc

 

actually most of the stuff inside the fbx isnt needed aswell only the raw mesh data.

 

afaik blender creates smaller project files than most studio solutions.

 

So what happens to the mesh when we export? Is it placed in a folder of the game's directory? Do you know the location? The most important question I would like answered by an developer is are the trees instanced in the game?

[Shelltoe 15]

hm? dunno if i got you.

 

actually nothing happens to the mesh while exporting to fbx (besides triangulation maybe). it's just a format CSL can handle. CSL can handle OBJ and DAE too.

your exported fbx should be placed here:

 

The model import user folder is located at:

• On Windows C:\Users\<username>\AppData\Local\Colossal Order\Cities_Skylines\Addons\Import
• On Mac /Users/<username>/Library/Application Support/Colossal Order/Cities_Skylines/Addons/Import
• On Linux /home/<username>/.local/share/Colossal Order/Cities_Skylines/Addons/Import

 

if you import it to CSL your mesh + lod  + the textures will be stored in a new .crp file in the "Assets" folder right next to the "Import" folder

(workshop items are stored somewhere else)

[Mr_Maison 2,426]

hm? dunno if i got you.

 

actually nothing happens to the mesh while exporting to fbx (besides triangulation maybe). it's just a format CSL can handle. CSL can handle OBJ and DAE too.

your exported fbx should be placed here:

 

The model import user folder is located at:

• On Windows C:\Users\<username>\AppData\Local\Colossal Order\Cities_Skylines\Addons\Import
• On Mac /Users/<username>/Library/Application Support/Colossal Order/Cities_Skylines/Addons/Import
• On Linux /home/<username>/.local/share/Colossal Order/Cities_Skylines/Addons/Import

 

if you import it to CSL your mesh + lod  + the textures will be stored in a new .crp file in the "Assets" folder right next to the "Import" folder

(workshop items are stored somewhere else)

Thanks for the info. The .crp file in my assets folder is around 2.6mb (2,570kb). That's a drastic decrease from 32.98mb. What do you mean C:S can handle obj and dae too? Are you saying the model don't have to be FBX all the time?

[Shelltoe 15]

well you can embed textures in fbx. so the fbx would be much bigger doing so. but CSL doesn't  care about it anyway so just skip it

in general your model will have the file size of your textures + a few kb. 

 

 

though right now the actual crp file size seems to change with the template you use. as if the original texture data is still in there or something.

 

eg. i have the same building 2 times in the workshop. the actual file size of all my textures + the mesh is around 1mb

 

1x lower commercial level 1 4x4  -> workshop says 3mb 

1x lower commercial level 3 4x4  -> workshop says 13mb (!?!? it can't use color variations either) 

 

EDIT: I haven't tried texturing a .dae or .obj yet but yes the mesh will load ingame.

[graphite. 2]

Making foliage is not so easy, and takes some time/practice to get it looking right whilst keeping the polygon count down. Within the Unity engine you can also tell it how the billboards should react. i.e static or face camera and at what distance they should start to rotate. I'm guessing for CS this could be done through the API. At the end of the day you can get some pretty good results with very few polygons. 

 

 

 

Keep in mind these numbers work well with the billboards always facing the camera, for static you would have to throw a few more polygons at it

[Mr_Maison 2,426]

Making foliage is not so easy, and takes some time/practice to get it looking right whilst keeping the polygon count down. Within the Unity engine you can also tell it how the billboards should react. i.e static or face camera and at what distance they should start to rotate. I'm guessing for CS this could be done through the API. At the end of the day you can get some pretty good results with very few polygons. 

 

Hey Graphite, good to see you here! Nice tree!

 

Did you get that tree in game?

[graphite. 2]

Hey Mr M,

 

were like birds of a feather ...  

 

re modding: on day one of release I quickly threw in a couple of assets I had lying around just to check out the work flow. But with the amount of free time I have, I can't see myself doing any modding for CS at the moment. Got some time off coming up in a couple of months so that may change then. In the meantime thought I would pop in here just help out, if and when I can.  

 

Looking forward to seeing how you progress with your foliage though

 

cheers mate 

 

 

 

 

 

[Mr_Maison 2,426]

Graphite-Looking forward to your input and free time.

 

 

Question: Does anyone know if the size of trees is capped and if we can make them taller and wider?