texturing a race track

kypo

Hey

I wanted to ask what is the best way to texture a racetrack?

At the moment I’m struggling to put skid marks and other track markings on the track with out using masks. How would this normally be done in a racing game? It’s the same for the terrain. Would things like vertex colour blending be used or is just maps? Looking at games like flatout 2, using just maps to blend in all those details on the ground would need alot of maps.




I included this image as a example the tire marks i mean.

And this is my track so far.



Its early but the track issue has been bugging me.

Any input will be greatly appreciated.

Rick Stirling

Decals, or multilayer materials. Each layer can use the same geo but different uvs, so you get one set of tileing track textures and another set of skidmarks.

Jesse Moody

[ QUOTE ]
Decals, or multilayer materials. Each layer can use the same geo but different uvs, so you get one set of tileing track textures and another set of skidmarks.

[/ QUOTE ]

I think this is how I was going to do it when I was planning my track project. After playing Forza 2 I might just revisit that project.

Joshua Stubbles

Per-Rick nailed it. Decals and multitexturing.

kypo

Thanks for the replies guys. I think i was going along the lines of what per was say, i was thinking to much on technical restraint instead of what would look good. from what i have seen, Modern shaders are so flexible that any thing that i can get to render in max is possible with in a game engine. I'll play round with some decals and see what you think.

odium

For your terrain you really should look into some blending, whether its vertex blending or not. ATM your grass looks to much the same, all over, then it sharply hits rock. Blending between the two all over the place a little with a softer blend where you need rock will help a LOT.

As for the tyre marks, decals are usually the best bet to keep the polycount/fillrate low, while still adding in what you need. It also means you can make them as sharp or soft as you want/need.

CrazyButcher

for terrain vertex-blending would definitely be most suited. texture stuff would eat too much memory, and for a race game its sufficient to have vertex accuracy and just spend a few more tris to get good enough vertex blend zones.

about decals, the most efficient way would be packing different "grooves" next to each other in one texture. and then have all decal strips be the same mesh but have uv shifted to pick one of the grooves. the grooves could still tile vertically, to compensate reptition in longer trails.
for "fade in & out" of a trail you could use vertex alpha again for the end&start edge.

on a sidenote, if that track is dynamically "vertex lit", you might want to cut that big poly in front of the tunnel into smaller ones that have a more "even" distributed triangles. else you will get shading artefacts. (actually you should see those in the viewport, too). Though ignore if you manually bake light into vertices or a lightmap

kypo

morning,

ok bit of an update, been playing with the decails and haven't quiet got the hang of it but am getting there. i was using strips of tire marks for the straights and corners, but found that i needed lots of polys on the corner peices to prevent warping, so i have created a seperate decal for the corners.

Some thing look weird with the scale in the scene at the moment, any thoughts?





thank!

vkirchner

I like it, overall it looks great. The only thing I wonder is, the sand or dirt area appears to be very early in the curve. But maybe that's the way it really is. The tire tracks could be varied a little more as far as darkness, but I love the layout. What does the rest of the track area look like, any sketches?

Toomas

You cant really model good track like a fps map. Racing on a flat surface is very boring. Ofcourse you could do more detailed collision geometry for the track but then the player has no visual clue and its annoying to guess and remember.

Ryno

The trees look quite small. Look at the catch fences, which are usually 12-15 feet high. The trees are just slightly bigger than that. In real life, a pine tree is probably more like 50 feet high.

Also, add some more segments to your curves. Those are looking very chunky right now.

I'd recommend getting down on track level, and working on making the stuff on and near the road surface as good as possible. This is where you need the most detail. If you're using Max, put a camera on a path to drive the stretch, and use walkthrough mode to look around a lot, from the perspective of the player. Once the stuff near the track is looking solid, move your way out further from the track, where objects do not need to be as detailed.

A lot of our tracks on Forza and Forza 2 look kind of odd if you take screenshots of them from 50 meters above them. The entire game is meant to look best from the player's perspective, so as we tested stuff this is where we'd like to view stuff from.

And people have got it right with the multi-texturing + decals. You absolutely have to use multi-texturing to break up the huge expanses of tiling terrain, gravel traps, road surfaces, etc. Whether you're doing this with vertex blending or alpha maps depends on the game. We mostly used large area alpha maps for the games that I've worked on.

kypo

Thanks for the input,

@ toomas - I was approuching the model as only making this section, i could maybe some strong visual clues like a tv camera stand tower on the opposite side of the main stand ect.... hmmm

@ Ryno - cool post, got me think alot. so far i have been modelling it from above, so added a camera like you said and it has changed my view on how much more detail i need on the road surface than the barriers ect.... the trees look sort dinky when look at from track level, and the track doesn't feel wide enought. at the moment i am thinking of going almost back over the model and using the current one as a referece to my new one. there goes a couple of hours down the toilet... i'll try getting a new thread started on the pimpin and review side of the boards as this track is turning into more of a project now.

What would be the normal work flow on a forza track?

tar

Ryno

It's really quite a huge process, and not one that I can totally convey here without writing a book. But getting the road drivable and the curves smooth would be a great first step. Then get the terrain blocked out, and snapped to the road edges. Use proxy objects to block out where trees would be, grandstands, etc. Begin doing the initial tiling textures for the roads terrain, etc. Place barriers. Replace proxy objects with finished prop models. Set up collision, AI splines. Figure out the changes in terrain type (grass to dirt, dirt to mud, etc.) Cut geometry where seams will be hidden, and begin making masks for large area terrain transitions. Make variations for tiling textures. Bake lighting. Add decals.

Props really close to the track need more resolution in texture and geometry. Don't short these object. If you must cut corners somewhere, cut it on the props that are off in the distance. Also make sure that your texel density on any surface that you are driving is nice and high. Cracks, ruts and pebbles zipping by underneath you really give you a great sense of speed, and blurry blob texture does not.

That's not all in the exact order that you'd do it every time, and I'm sure that I'm forgetting some stuff, but that's a pretty reasonable summary of the workflow.

I just worked on another racing game: http://games.teamxbox.com/xbox-360/1498/SEGA-Rally-Revo/ where we used a crazy combination of masks and vertex blending to get some really nice terrain variation. This has been a really fun game to work on, and I hope to share more about it once it gets released.

kypo

Thanks for the run on the work flow. think i might look into maybe starting a new piece, gettting some sketches down first this time instead of getting to a point that i'm not sure what to do next. i was thinking of maybe seeing if i can get a road shader made up that varies the road a bit better with maybe a large 1024 x 64 pieces of road and then layer the colour differences on the road inside the shader, hopefully that will keep a nice amount of details in the road surface and prevent the blur-ness.

The new sega rally games look cool, the effect on the road which allows the cars to cut through it look similar to the effect in motor storm. i did wounder why the new colin mcray didn't have a similar one. I'll look forward to seeing some pro modelling and texturing shots of the game when you can.

Rick Stirling

Hey Ryno, did you guys do much LODing on both the tracks and the props?

Check out MotoGP 06 as well.

vkirchner

Kypo, here are a few textures that you might be able to use.

Road Texture #1



http://www.sharecg.com/view.php?upload_id=3921


Road Texture #2



http://www.sharecg.com/view.php?upload_id=3922



Road Texture #3



http://www.sharecg.com/view.php?upload_id=3923


Road Texture #4



http://www.sharecg.com/view.php?upload_id=3924

vkirchner

Road Texture #5



http://www.sharecg.com/view.php?upload_id=3925



Road Berm Texture#1



http://www.sharecg.com/view.php?upload_id=3926



Road Berm Texture#2



http://www.sharecg.com/view.php?upload_id=3928



Road Berm Texture#3



http://www.sharecg.com/view.php?upload_id=3929

vkirchner

Road Berm Texture#4



http://www.sharecg.com/view.php?upload_id=3930



Road Berm Texture#5



http://www.sharecg.com/view.php?upload_id=3931

Genjix

When we wanted to texture a track in a futuristic racer, we got some scripts written that converts and unwraps bevelled curves, so you don't have to convert the mesh before exporting and you have good unwrapping.

Ryno

Rick, for Forza and Forza 2, no. Just streaming, afaik. For Sega Rally Revo, yes we did use quite a bit of LODing.