Development Q's doe the 3D side of things iPhone related

Could not think of a better title :sweat_smile:

It’s been a while since I posted and had a chance to browse the forums so maybe I missed an awnser or two, but any help would be a huge thanks, to note I do not know code but have been learning it from a book, so i’m a good year away from knowing and understanding the advanced code ways around problems.

As a 3D modeller I have been working on iPhone assets for a while now but I have not been able to find some solid awnsers on a few things, the first thing I need to ask is to do with making a huge world, I read that the idevice will only try to render what is on the screen but at the same time if I am making a racing circuit I would need to limit draw distance somehow anyway to stop all the track ahead of the player being loaded in, the two ways I was thinking about this are:

  • Build the circuit as 20 pieces, making only 3 appear visually at one time, player always in the middle of the 3 so he can see ahead and behind.

  • Make the entire circuit and tell Unity to only load up to 200meters ahead of the car.

I am not sure if Unity can so the second method directly or not, maybe a script or something? The racing circuit would be point to point, but I am thinking that also keeping track of 3 segments at all times may take up a few too many draw calls.

My second question is to do with Unity’s built in physics for making balls roll and car’s drive about, does this take up quite a bit of resources and draw calls to make a 4 wheeled car drive around with some kind of physical suspension? or am I thinking that this is too much to ask on top of a few k’s of polys too? For the wheel collisions I was going to overlay an invisible but simple mesh which would be your wheel detection, keeping the car only on drivable areas without worry of having the entire scene as a collision.

A huge thanks to anyone in advance if they can awnser, I included some visuals on what I am working on (NOT ingame as I can not code)


The car is just under 1000 polygons (would be the only vehicle on screen) with a single texture 256x256, the world is also low poly and using one single 256x256 texture with an alpha map.

You might try the first technique above via some manual control of what’s loaded and where. Or you just might be able to do the second technique by using occlusion culling, although that’s typically best suited for indoor environments more than outdoor ones, but it’s worth considering. Maybe others can chime in with their own thoughts on that.

Well, physics itself doesn’t incur any draw call hits so I wouldn’t go that route. But with that in mind you have to think carefully about your use of physics as it’s a phone, not a desktop PC or something like that. But with that in mind driving simulations can (and have been) done in Unity already so the engine is up to the task physics-wise.

Thanks for the feedback, building the circuits in chunks sounds like the best way, maybe adding in some volume zones so it’s only displaying the segments it needs to do.

I seen games using unity with physics based suspension and movement but they all look simple, something I was worried about was how much of a performance hitter it is, I will worry about that more down the line as I still have a lot of assets and target renders to make.