W.I.P. Dallas 1984 Grand Prix Street Track

[EKO Sim-Racing]

Hello to all,

After all I have read and learnt, I've decided to revamp completely the Dallas 1984 F1 GP track I did for F1C and rF1 and get it properly into Assetto Corsa.

Everything will be done via:
- 3DS Max 2017 (sorry for the Blender affiliates, but I never used Blender)
- using LiDAR data to make it as real as possible (see below pic).
- using all my research from over the years of what I know about the track
- using your precious advice to make this as good and as fast as I can.

I had started doing a revamped update of this track for rFactor 1, where you can see some puny results somewhere on the internet, and halted once I got my hands on LiDAR data, to figure out how to use it.
The new edition will be insanely better than anything I've done before, first step I GOT THE LiDAR DATA (YESSS!):

(ugly red line is where the track portion is)


I will notify that this project will not go as fast as most people mod here, as I do not have a zillion hours of free time on my hands, but I have a few in the evenings #ijustrealizedthatissadtosay

Anyway, I like this track a lot (even though it would have been hell to drive for real on this in the same conditions the F1 drivers did back then), the circuit is a pure street course and actually quite fast, with cambered corners and elevation differences all around.

I will need some pointers from you as I go along on this, but I hope to teach a few tricks to some of the new or future modders.

Maybe I'll even see about making a few video tutorials also using this track as the reference.

Cheers,

Nericksenna

 

[EKO Sim-Racing]

So let's see... how to start off this sort of blog/forum/tutorial/diary whatever..:
Oh, before I go any further, HUGE KUDOS to many here such as luchian and DanTDBV, reading your stuff was awesome (albeit a bit eye-stabbing when into the real technical meat of the topics, but great anyway).

For now, I have been able to get the LiDAR data (as you can see in my previous post).
I've been using CloudCompare (free and pretty damn performant little tool) since last year and just this week figured out a very fundamental thing (albeit very easy): separating the ground + sidewalks from other objects (buildings, trees, cars etc).

This gives me a perfect point cloud with only the ground, street and kerb with the necessary elevation data to make the track.

If anybody is interested in this quick trick, please let me know.

 

[luchian]

Hi there, welcome . I honestly believe that there are too few street circuits in AC, so this will be a very nice addition (even if personally I am not a huge fan of historic tracks - maybe this will change).

On a side note, I would be curious to learn about the separating stuff trick; I might get my hands on some laser/lidar data in the not so distant future, so it might be handy. No hurry though, it's not for "tomorrow" .

Good luck with the project.

 

[EKO Sim-Racing]

Thank you luchian
I am almost sure that I can change your mind on historic tracks, especially here because this particular one made for some very good racing in real life, so I am sure in AC it will provide also.

OK, for the trick:
1 - Load up your LiDAR data (I have a LAS or an LAZ) within CloudCompare.

2- If you have many portions of LiDAR, which was my case (I had 4 major portions, representing the entire city and suburbs of Dallas Texas (I just need the Fair Park portion for the track),

Spoiler: like explained here

https://assettocorsamods.net/threads/lidar-point-cloud-to-mesh-tutorial.422/

and merge your portions into one big portion. Up to this point nothing very new..
Now make sure to select your point cloud.

3 - The new part: in the Top Tool Box (TTB - you know the horizontal ribbon on the top of the program where there's File / Edit / Tools etc), go to the Plugins thumbnail, go down to CSF Filter (if you do not have this plugin, just download and install the latest version of CloudCompare) like this:

4 - A text box appears, and in the General parameter setting you'll have different types of data separation processes (I personally chose Steep Slope, I haven't yet done Relief, but I'll try it out next chance I get to do so as it might be better end result). Don't hit OK just yet

5 - Go to the thumbnail just next to General parameter setting which is Advanced parameter setting. Within this I believe we can really fine tune our ground capture and separation (this will have to be played around with in the future). For now I just left the default parameters:

All right, now you can hit OK It might take a bit of time to compute, depending on your CPU..

6- That done, you will see 3 things in the DB Tree (the arborescence tree on the top left next to your point cloud viewer):
--- Your original (or merged) point cloud data
--- Your new point cloud data separated into two subtrees called "gound points" (this is our track surface and kerbs depending on the samples taken with all the elevation data)
---and "off-ground points" (this is whatever is above the ground, i.e. buildings, trees, cars, maybe even people walking around during the laser scan). To see just the ground points, un-tick all the data point groups except for "ground points" and VOILÀ !

Hopefully this little trick will avoid people going insane on selecting polygons and removing them painstakingly like I did for many minutes or even hours depending on what is wished, and most of all, having a clean selection / separation of ground data and non-ground data.

 

[luchian]

Oh, that was fast. Thank you. Definitely not something I would've found easily "by clicking around" .

 

[EKO Sim-Racing]

Ok everybody, I just made a few video tutorials to explain a bit better the first steps of what I did.

Feel free to comment and give your suggestions:

 

[luchian]

Thank you for taking the time to do this. I am sure it will serve many people.

 

[EKO Sim-Racing]

Well, I hope it helps, I mean I really tried to understand step by step on the written tutorial in a sticky in this forum on how to do LiDAR tracks, or at least use the LiDAR data. But not everything went to what was hoped for... So now that I know a few tricks (not just the one I mentionned above) hopefully it'll take less time to make really good and precise tracks.

Ok, so now I have a really cool looking track with perfect height data, I'll try to make a tuto video this weekend if I have the chance (time).

Quick question: How can I make a lot of marbles on the track like this ? And is it possible to make them appear after a certain amount of on-track time ?

 

[Prototype]

Quick question: How can I make a lot of marbles on the track like this ? And is it possible to make them appear after a certain amount of on-track time ?

I would imagine, using the GROOVE function could do something like this ... ?

 

[Prototype]

Awesome thread btw.

 

[luchian]

I would imagine, using the GROOVE function could do something like this ... ?

Yes, for progressive build-up, only groove could do something . Here some info on how to set it up.

 

[EKO Sim-Racing]

Ok, so I put the track in game, there are some really bad bumpy areas, I guess where there's some jagged height data, how would you advise on this ? I don't want to loose any valuable height data, but I don't want the car rocketeering off into the crowd in a normal corner..

 

[Pixelchaser]

Ok, so I put the track in game, there are some really bad bumpy areas, I guess where there's some jagged height data, how would you advise on this ? I don't want to loose any valuable height data, but I don't want the car rocketeering off into the crowd in a normal corner..

one has to treat the data as a reference and build upon the data with geometry suitable for game world and most commonly done via spline modelling. this also means the step where you optimised the resolution of the data might not be correct thing to do as the new geometry you build will be the averaged out data (smooth) if the data is 1 million polygons raw data then that's what you should build upon. the point being the data is a reference for the actual modelling seen in game.

 

[EKO Sim-Racing]

Ok well in that case, I should be fine then, I'll just have to optimize it manually.

Effectively, I do spline modelling:
1 - center spline
2- inner track spline
3- outer track spline

Then I delete the center spline (or keep it as a UV reference spline for later), conform the inner and outer track splines to the ground mesh. After that, just cross-section both splines and that gives me my track surface.

I mean, in all, the track is super accurate, it's just in some parts where it's a bit jagged (like in a chicane or cross corner).

 

[Pixelchaser]

yeah lidar is great but just never perfect. I optimised my lidar to a uniform mesh that was same resolution as the original, creates minimal averaging, then laid splines points every 6 m or so. then visually checked for nonsense data and removed what was needed in that area to maintain smoothness. corners cambers are usually there nicely but might need enhancing and its usually quite nice.

 

[EKO Sim-Racing]

Any use of me doing a tuto video on how to do this ?

The 6m intervals is a good trick to know, I've been winging it up to know: I did 1m, 2m and I think the last I did was 10m (and IMO this is a bit too much...).

 

[Pixelchaser]

there is no rules really. just best practices at the end of the day and it can be different for every track. assuming the data is incorrect can force you to look at it more too. sometimes that can make things better.

 

[EKO Sim-Racing]

I tried the same method on another track I'm working on at the moment, but since the track is already flat as a board... no real need to use LiDAR.

Any advice on the texturing I've done below ?

 

[EKO Sim-Racing]

yeah lidar is great but just never perfect. I optimised my lidar to a uniform mesh that was same resolution as the original, creates minimal averaging, then laid splines points every 6 m or so. then visually checked for nonsense data and removed what was needed in that area to maintain smoothness. corners cambers are usually there nicely but might need enhancing and its usually quite nice.

Just so that everybody understands what Pixelchaser was talking about, here is a really good (and I find one of the coolest things to do in 3dsmax) tutorial:

 

[luchian]

Any advice on the texturing I've done below ?

While the "shading" is ok, it looks low-res. And that decreases the value of the job.
All you need to know for top notch roads, is here: https://assettocorsamods.net/threads/photo-quality-road-surface.834/