Hi, CAWers!
As we can see, there are a lot of nice worlds available, but many of them are not playable for low-end computers, unless you set the graphics to minimm, but that is not a solution (for me) as all aesthetics is lot then.
I am working on a world now, my machine is pretty good, but as i use a lot of CC, large worlds still lag for me. So, I want to ask, what causes lag?
I know, this is caused by:
1) skyscrapers
2) large number of lots
3) many trees
4) too many terrain paints (esp. if there are more than 8 per chunk)
5) overpopulation (that's when the world is already being played)

What else can cause issues? I am especially interested in the following:
1) many CAW objects (all those railroads, bigboards, light, fences...)
2) is it better to use more small lots or fewer, but bigger lots?
3) many tree species
4) roads/sidewalks density
5) what's more practical, curvy roads and multilevel terrain, or larger peices of flat terrain and straight roads (that's what I'm more into, my roads in the city part are straight)

for all of those you have listed, I would rule out most.

CC are objects as any other game objects. They do not cause any more lag than the objects you get with the game.
Skyscrapers should not cause lag
Large number of lots CAN cause lag, if the amount is ridiculous, ie. +200 lots
Many trees should not cause lag at all if are clustered
Too many terrainpaints should not cause lag either, unless one has very crappy graphics (then they should not be playing sims anyways)
Overpopulation, relates to too many lots I suppose.

What causes most lag is badly done routing. You can find many threads about the routing there at MTS, one tutorial done by the signed too. This relates to placing CAW objects, lots, roads, trees, basically everything you can put to a world. So plan and do the routing with care.
I don't know if it's better to use smaller or bigger lots, this too relates to the amount of them.
Many tree species - should not cause lag, again cluster the plants and trees.
Roads and sidewalk density effects routing. If you make sure everything you want accessed IS accessible, and everything you don't want accessed IS properly blocked with unroutable paints, you should not have issues.
Road shape and elevation should not effect anything else but the looks.

What also effects the performance, is how you layer the stuff. Some people put everything in one layer, some make layers for areas, and some for types of stuffs. For these, the first is an option I would not recommend.

So, as a quick summary:
- Plan your routing with care, and also check that you don't have spots that are not connected.
- Keep sense in placing lots and population. (and again, keep routing in mind)
- Cluster your plants and trees.
- Make use of the layers. Either grouping the stuff by type, or area.

Number one cause of lag is poor routing.
http://www.modthesims.info/showthread.php?t=439329

Skyscrapers I probably disagree with. They are just building shells, and so provided the building within is not overly complex and does not have any routing problems, I can't see why they should cause problems. The shells do have a sound effect, but so do trees so that shouldn't cause lag. Unless you mean lots built using CFE to give more than five floors? Same applies, as long as the complexity and routing is ok, no issues. Here's some detail about lot routing from my experiences:
http://modthesims.info/showpost.php...4&postcount=395

Trees- if you have a large number of trees then yes, that increases the complexity of the world and so can cause lag in low spec computers. But, if you place all trees on the same layer, CAW will group them by species, so increasing performance. So having too many species could decrease performance slightly.

Many CAW objects- yes, but again this is referring to the complexity of the world. The more objects you have, the more polygons there are to render and the more complex the routing is. If you have a lot of objects or lots clustered together then low end computers may notice a reduction in performance when in that area. So perhaps space out lots and use trees, plants and objects sparingly if you want to make a simple world.

For the question about lots (is it better to have few large or many small), then that depends upon whether you are playing the lot or not. If your sim lives on a huge lot with a huge building on it, performance will be worse than if you play a small lot. If you send your sim to walk down the street then the larger, more complex lots will take more computer power to render high-detail, but if you set your computer to only have one high detail lot then everything else will be low detail.

For the question about which is more practical, flat straight roads or curvy roads, then that depends. If you look at the routing thread I linked to you will see that the more objects you have, the more complex the routing becomes. So if you have an area of wilderness with hills and curved road, the routing will be simpler than if you have a straight, flat city street with many lots and objects. The terrain doesn't change in complexity at all whether it is flat or hilly- it is still comprised of a grid of a constant resolution (complexity). Roads too are just a routing spline which changes little whether the road is flat, curved or hilly. But if you break the road with objects, or place trees on a hill then you are automatically increasing the amount of work the computer has to do to calculate the sim's path.

Things you have forgotten:
Effects- like the lighthouse effect, waterfalls, birds. The more of these the harder the computer has to work.

Lights- If you jam pack your streets with lights then you will up the resources needed. Use them sparingly.

Spawners- Use only what's necessary, the computer has to work karder to aniate and fire these.

Registers- that includes stages (proprietor spawning), consignment stores, LN bars, the exclusive lounge velvet ropes- each time you use one of these, the game will create a sim to man these objects. So use them sparingly if you want to keep the population down.

World size/ height- The height of a world will affect its size too; a small 300 high world is more complex then a small 200 hight world. Think of it as a cube.

@Armiel- I disagree about the layer thing, there is no indication that having many objects on one layer will cause problems. The only items that matter for layers are plants and trees.

Also, I disagree on the terrain paints- when I had a low end computer, I could sense lag when I went from a chunk with few terrain paints to a chunk with more than 8 terrain paints. So keeping a low number of terrain paints per chunk will definitely help.

A related question...

I'm about ready to put down lots of spawners, and I'm wondering how many unique spawners in each category(seeds, gems, fish, etc.) are needed to unlock all the rewards like the 'heart cut' for gems and so forth. Is there a general rule of thumb? Obviously, you wouldn't want to restrict your world that tightly, but it would make a good starting point.

Oh Man! Where's a tardis when you need one? I need to turn back the clock before I read this.

Red boundary chunks cause lags, too? Starlight Shores has 3. Was just about to prepare the download thread.
Back to the drawing board...more reading for me! How fun!

When it comes ot spotting and swatting routing problems, you might want to look at this: http://sims3newyork.blogspot.com/20...-yet-again.html

If I read this right, a large world with X-amount of lots split up on all the chunks create lesser lag than a small world with the same amount of lots, since it have fewer chunks ant the lots therefor have to share the chunks, right ?

I think that would depend upon the complexity of the lots and the complexity of the chunks, for example routing complaxity, number of CAW objects, terrain paint complexity. It would be difficult to give a formula or quantify this as there are so many variables.

But if we are talking about the exact same lots, but in different world sizes. ?

I'm just trying to understand the mystery of CAW

I like that phrasing...CAW is a mystery. simsample has done as much as anyone to quantify it, but there are still vast expanses of unexplored territory out there. Even Pescado calls it Create a Crap. Me, I think it may be the best thing Maxis ever made, even with its flaws...best of all, it's free..my favorite price.

One way to find out would be to test it. I look forward to your results!

ha ha ... guess that I asked for that answer well, I'm not the fastest builder, so it will take a while before you will get any results

@PF I agree, CAW is a great tool, too bad that it is made unavailable too so many, by making it so complicated ... it is easy to slap down a world, but difficult to make a good world

I tend to think that world-building is inherently complex. I don't think the CAW tool is bad at all, for what it needs to do.

I think that has a lot more to do with lack of patience than because it's intrinsically a bad tool. People expect too much too quickly.

Aside from bad routing most of the factors aren't necessarily an issue by themselves, it's more the interaction between them that matters.

The terrain paints per chunk really shouldn't be that big a deal, we're talking about 8 1024x1024 textures - you would get the same graphics processing demands from having 8 Sims on an empty lot. Also if you used 512x512 textures instead, then the 8 limit makes less sense. It also doesn't make any sense to keep to the 8 limit and then go mad using tons of lot terrains.

The number of lots - again, depends entirely on the whole picture. Yes I suspect 200+ residential lots would be a problem because the game doesn't really support populations at that level, but if most of the lots are small, decorative hidden lots or which otherwise don't attract Sims, then a high number of lots isn't by itself a problem.

Weather would also be a factor. It strikes me that tuning down the demands of the cloud speed, sea noise and wave speed etc, could be used effectively to mitigate against higher demands in other areas.

I've seen that it does make a huge difference on low end computers, although on my new computer it isn't noticeable. You can't really compare 8 textures to 8 sims- for a start, they are stored completely differently. The terrain paints are stored as image resources in the world file itself for each chunk, and the game reads these resources and applies the tiled texture each time the camera is within that chunk. So if more layers of texture are being rendered in a chunk this will have resource implications for everything else on that chunk, since the terrain is always rendered. I don't think world terrain paints are something which you could just dismiss as being a trivial resource commitment when you are building for low-spec computers (or for performance), and you can't really compare chunk textures to lot textures either, as they are dealt with differently.


I'm not sure that changing weather parameters has much impact on performance, apart from the randomize interval (how often a new weather is chosen). The clouds, sky colour and waves are rendered whether they are animated or not, and cloud speed, water wave pattern and direction has not made any impact on performance in my tests. I have found that a small lag will sometimes occur on a low-end computer when the weather is randomized, but this happens in the EA worlds as well as custom.

Thanks for tutorials, Simsample and Armiel.
Hell, that routing is the most complicated thing, esp. on the hilly roads. I checked all my roads for routing issues and found a lot of them to fix.
Now, about the clustered trees. As I understand it, when we install a world into the game, the trees are clustered, and objects belong to different layers, but when we place trees in World Editor, they aren't clustered, and the game considers each single tree or object as a separate item, which increases lag? I'm asking because I often do this to both EA and custom worlds - take down some trees and replace hem with other ones, or just put new trees.

A few details I've posted on Pasimfic Wiki:

From Rebecca of the EA world building team:



TS3's tech director and the WB team responding to this tutorial by eyelem:



If you have questions for the EA WB team about best practice, send them to @SimGuruSarah on twitter. She is likely to pass them on, and you may get a helpful response.

Thanks for that, kiwi_tea!

I'm glad we have some confirmation on the layers; it was as I suspected.


No, trees don't group across layers. They have to be on the same layer. For the EA worlds they have one layer per region or neighbourhood- for example, in Sunset they have a layer for Pinochle, a layer for the main town, a layer for the beach area. Everything- lots, trees, objects- for that area is put in the same layer. So the EA worlds have some trees on the same chunk which are not on the same layer- so will not cluster.

SommarBlomma- The trees you add in World Editor in-game are not stored in the world at all- they are just in the save game. So yes, they would be treated as individual objects.