Jump to content


Track building basic tutorial


  • Please log in to reply
202 replies to this topic

#181 Larko29

Larko29

    Denny Hulme

  • Supporter
  • PipPipPipPipPipPipPipPipPipPip
  • 375 posts
  • Gender:Male
  • Location:Down Under
  • Interests:...
  • Sim interest:GPL

Posted Sep 16 2014 - 02:36 AM

Hi Nicholas

Pretty sure they need to be rounded off, Trk23doz has a function to help in this regard, if you don't have this tool it is most likely on the thread you got Gpltrk from. If you load up the .gtk in that it should do alot of the work for you, might just be some minor tweaks required.

Craig

#182 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 16 2014 - 03:16 AM

I have trk23doz, haven't used it yet though. The problem is that some of the info you find on the web is outdated by newer programs, so it gets a bit confusing for me. I've now made a track with GTKMaker. I can load it in GPLTrk to zero the start/finish. Some questions in this regard:

-is it best to zero the other sections now, or don't bother yet and first do the other tasks of track building? (walls, heights, 3DO's, textures)
-is it best to zero the longitudinal gap, or make it slightly negative or positive? (sometimes GPLtrk can't get it at exactly 0)
-I will end up with one lateral gap of about 20mm. Apart from the possible visual consequences, I understand this is no problem for the track?

Edited by Nicolas, Sep 16 2014 - 03:37 AM.


#183 Larko29

Larko29

    Denny Hulme

  • Supporter
  • PipPipPipPipPipPipPipPipPipPip
  • 375 posts
  • Gender:Male
  • Location:Down Under
  • Interests:...
  • Sim interest:GPL

Posted Sep 16 2014 - 06:20 AM

Hi Nicholas

I'm by no means an expert on this, but I believe all mismatches need to be addressed to ensure the track is stable for online racing.

Have a look here http://srmz.net/inde...topic=4047&st=0   Post 19 has some info relating to the management of gaps.

Do you have access to MS OneNote? I have pages from the old GPLEA site which had some good background info relating to building  track

I'll see if I can dig up some more info for you.

Craig

#184 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 16 2014 - 07:17 AM

I've tried the techniques described there. Ignoring some petite lateral gaps, I've all orientation mismatches at zero and all longitudinal gaps at zero, except for a -1 between two curves that the program can't get out of it. But as far as I understand, it is larger and multiple gaps that lead to unstability. So maybe we can live with one -1 gap? Edit: I just read that while orientation mismatches MUST be at zero, a "small" longitudinal overlap of less than (minus)500 is OK. -1 will be fine I guess. :) It's longitudinal gaps (positive gaps) that are the problem.

Edited by Nicolas, Sep 16 2014 - 07:20 AM.


#185 sergioloro

sergioloro

    Denny Hulme

  • Supporter
  • PipPipPipPipPipPipPipPipPipPip
  • 299 posts
  • Gender:Male
  • Sim interest:GPL

Posted Sep 16 2014 - 07:46 PM

gaps of value 1 unit  or 2 unit are OK, at least with all tracks i made :) i think most important is to have all 0 gaps at start/finish section.

#186 Michkov

Michkov

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 879 posts
  • Gender:Male
  • Location:Graz
  • Sim interest:I am here to spam and wish to be deleted after registering

Posted Sep 16 2014 - 11:24 PM

My understanding is that gaps should be avoided, so overlap is ok as long as you keep it small. Longitutinal and orientations mismatches are the dangerous ones, lateral alone should be fine.

I usually zero the gaps when moving from GTKmaker to GPLtrk, or at least move all the gaps to the last curved section. Problem is once you start splitting sections you'll get gaps again, so you'd have to zero it all again anyway once you're done with that step. If you dont compile the track in between steps you can leave the gaps in until you're finished with the trk I think

#187 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 17 2014 - 04:46 AM

OK, clear!

#188 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 20 2014 - 05:12 AM

When applying a texture to an 8m wide track (-4 to +4 wall), the asphalt is nicely 8m wide but it tiles along the centerline instead of along the edges (so everything is shifted half a track width to the side). So if you have an asphalt texture with black asphalt, a white line on the left edge and a red line on the right edge, you would see black-red-white-black in game instead of white-black-red. How can you change this? My tex entry looks like this, and I see no way to give it UV coordinates: 1 0 0 15.0 8.0 asphalt

Edited by Nicolas, Sep 20 2014 - 05:12 AM.


#189 Phil

Phil

    Tazio Nuvolari

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 223 posts
  • Gender:Not Telling
  • Interests:I have no preference
  • Sim interest:I have no preference

Posted Sep 20 2014 - 07:48 AM

Unk4 flags in GPLTrk manipulate texture mapping, use 512 to map the texture once laterally

http://wiki.grandpri..._trk23dow_-_GTK

#190 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 20 2014 - 12:46 PM

It works, thanks! I'm learning a lot here, and the track is evolving nicely. Next problem: in trk23doz I can scale the track. It calculates the % correctly and saves as GT2. Now what? If I next just make the 3DO, it is not scaled. If I rename the GT2 into GTK, it is not scaled.

#191 Michkov

Michkov

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 879 posts
  • Gender:Male
  • Location:Graz
  • Sim interest:I am here to spam and wish to be deleted after registering

Posted Sep 20 2014 - 02:11 PM

The GT2 file is a backup of the GTK before scaling. The original GTK should be scaled. IIRC you have to zero the gaps as well as the scaling only affects the length of the sections not their overall positions

Edited by Michkov, Sep 20 2014 - 02:12 PM.


#192 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 21 2014 - 05:01 AM

I did some more tests, turns out it is the GT2 that is scaled. You can load the GT2 in GPLtrk, do the gapping details, and save as your new GTK. Very nice, now my track length is correct within 1m. Not bad for 10450m... Now that I have that, I took some time to create the correct starting grid in the INI. It starts to look better and better! Now on to the huge task of putting the right walls on all 250 sections, and then setting the altitudes.

#193 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 22 2014 - 01:13 AM

What is best: giving all sections the correct placement of walls first and give altitude to the track next, or altitude first and manipulating the walls next? If that order doesn't matter, I'd like to give altitude first to get a better feel for the track. But I won't go through adding all altitudes if next I find out that runs me into trouble with the walls...

#194 Border Reiver

Border Reiver

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 974 posts
  • Gender:Male
  • Location:St Andrews, Scotland
  • Interests:GPL and GPL editing
  • Sim interest:GPL

Posted Sep 22 2014 - 07:39 AM

In practice they might end up evolving together.

With altitudes, it is not only the track to think about, but also off track things like earth banks, curb stones, hills etc. You only get 16 traces to work with and these lines run parallel to the track centreline. If the track is always a constant width this is not so much of a problem, but it the track width changes then you might need to use traces for e.g. curbs for both the "wide" track parts and for the "narrow" track parts, and this quickly uses up the traces that you have available to use.

When placing the walls which make up all of the track surfaces and the scenery, you also need to be careful how these cross trace lines. Things can also go badly if you place the track wall change exactly on top of a trace line. The positioning of traces within track walls will also affect the mapping UNK4 numbers that you have to use as explained by Phil above.

As I said, you will end up using walls to make the track surface and also off track things like woods, curbs, maybe crowd lines, banks etc. etc., and my recommendation is to get a "rough draft" of this first, maybe even on a piece of paper e.g. using a print out from GPLTrk so that you can sketch in what you are going to want. This can help you to "block in" where things will go and will show you any compromises that you might have to make between reality and what you can do using a sensible number of walls in GPL and only 16 traces. With the walls in place, you can then see where the traces will have to go to make these walls work, to raise up curbs, earth banks etc. relative to the track surface. This "blocking in" process of placing the walls may also lead to you having to split track sections in order to make the walls do what you want and produce the shapes that you want in the 2D overhead map. When you split track sections after altitudes are placed it messes up the altitudes since all of the altitude change moves to the first section, with the second section becoming flat, so you then have to resplit the altitude changes for each trace for the two new sections.

Obviously this is an "ideal world" thing, and inevitably you'll end up fine tuning walls after you have done altitudes and vice versa, so there will be some of this work to do at some point, but hopefuilly only in one or two places rather than for every section around the whole track. We all try to avoid having to repeat jobs, like rezeroing all the gaps, splitting track sections, moving walls etc., but always something comes up and you have to do at least a bit of that.

My personal advice is still to get the "2D plan" looking right in terms of where walls etc. will be, including doing any section splitting that you need to achieve this before embarking on adjusting altitudes, since where the traces are placed gets driven by where the walls need to be. That said, if you want to have a go at altitudes early on, for the overall track elevation then just use two traces, outside of each of the track wall limits and make the whole track world go up and down to give you an initial impression before you start on the individual traces to make local hills, curb stones etc.

Rob

#195 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 22 2014 - 08:35 AM

Quote

Things can also go badly if you place the track wall change exactly on top of a trace line. The positioning of traces within track walls will also affect the mapping UNK4 numbers that you have to use as explained by Phil above.
Or in other words, you're always in trouble. :) From the tutorial, I understood that it was best to have traces at wall edges? A bit contradictory...Now, for the moment everything is flat and I have no problems with this. About altitudes: if I keep all traces at the same height in parallel sence, I understand I won't run into too much problems/rework -except for when I split sections afterwards- while it would give me a good sense of altitude already. I might try that. If I save the altitude parameters of each sections in an XLS, it would be fast rework if required. thanks for your insights!

Edited by Nicolas, Sep 22 2014 - 08:36 AM.


#196 Border Reiver

Border Reiver

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 974 posts
  • Gender:Male
  • Location:St Andrews, Scotland
  • Interests:GPL and GPL editing
  • Sim interest:GPL

Posted Sep 22 2014 - 11:01 AM

I would say that you want them to be very near to wall edges, i.e. within maybe 10 to 100 gpl units, but not at exactly the same numbers. I forget exactly why that is, but I am pretty sure that Ginetto told me this at some point, and I have no reason to doubt him.

Saving the altitudes in excel for import/export is a great idea. Somewhere on this forum there should also be an excel file that someone made which will help you to do the maths of splitting sections and retaining the same original gradients for the traces. The sheet does the maths for you so you just enter the original section length and the coefficients and tell it what the new lengths will be, then it gives you the new coefficients for the split sections.

It was always my dream to make a track with a perfect workflow and no repetition of tasks or wasted effort, but it has still never turned out that way. Planning ahead and making loads of notes, diagrams etc. really does help in the long run though. It is tempting to press on ahead and try to do it all at once, or to hop backlwards and forwards when you get bored of placing walls or adjusting altitudes but that approach is not always so productive.

Also, make lots of back ups! At every significant stage I would always save a copy of the gtk just in case something goes wrong and you can't figure out why the track suddenly stops compiling, or some other problem happens! Every time you compile a new version of the track that works after making a significant change to the altitudes, or the walls, or the section splits or whatever then save a copy of that version of the gtk with another name so you can get back to that point.

To start with to get an impression of the altitudes then using very few (maybe even only 2) traces which are the same and only considering the "global" altitude changes is a very good idea. This gives you the feel of what you will be driving on. Once you have the whole "track world" following the altitude changes of the track, it is then relatively straight forward to make relative local changes to additional traces to build up curbs, hills etc. around the track.

Rob

#197 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 22 2014 - 11:31 AM

Thanks for all these insights! I'll share another one: don't wait until it's too late to start over again. My first go at the track was just based on a sat image. However, comparing with street level images, I simply don't have the correct straights & turns to get the actual feel of the track even though it matches the sat image quite closely (for example, a long continuous turn is a whole other thing than straight-turn-straight-turn to race on). I'm still in early stages, so in the long run the fastest thing to do is to add notes to the sat image, and start from scratch on a new GTK. You'll never make a good track with a bad GTK.

Edited by Nicolas, Sep 22 2014 - 11:32 AM.


#198 Border Reiver

Border Reiver

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 974 posts
  • Gender:Male
  • Location:St Andrews, Scotland
  • Interests:GPL and GPL editing
  • Sim interest:GPL

Posted Sep 22 2014 - 12:21 PM

Been there, done that. :)

At one point we had three totally different GTKs for Surfer's Paradise based on maps, architect's plans and satellite images and none of the three versions was actually really correct or would even overlay with any of the other versions. (Satellite images are great, and they are really useful, but they are not perfect and are a 2D representation of something that is not flat). Part of this comes back to the point about planning that I made and gathering as much information as you can find to begin with. The worst thing that can ever happen is just before you finish to suddenly find some new source which answers a nagging question that you always had, or which proves that the reasoned guess that you made to fill in a gap was actually totally wrong!

The plus point is that nothing is totally wasted and you always learn something from what you do, even if it is only don't try to do it that way again.

Good luck with it.

Rob

#199 Nicolas

Nicolas

    Denny Hulme

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 292 posts
  • Interests:Grand Prix Legends, Rally racing
  • Sim interest:GPL

Posted Sep 23 2014 - 12:15 PM

Meanwhile, I was wondering: is bump-mapping textures possible in GPL? some texts hint at it, but I wouldn't know how or where to get a bumpmap into a MIP...

#200 sergioloro

sergioloro

    Denny Hulme

  • Supporter
  • PipPipPipPipPipPipPipPipPipPip
  • 299 posts
  • Gender:Male
  • Sim interest:GPL

Posted Sep 23 2014 - 03:14 PM

not bump map!! just the .mip texture, what do you see with potoshop is what do you get in game :), with modern CPU we can use bigger resolution (dont go too extreme) and tracks can feel alive if we select the right set of textures.




1 user(s) are reading this topic

0 members, 1 guests, 0 anonymous users

Sim Racing Links