FreeGameDev

I've got an idea for a new track for Supertuxkart. The working name will be "Mountain Lane", because the track will lead around and into a mountain.

For the parts of the track that lead into the mountain I imagined something a little bit Indiana Jones like and for the parts that lead around the mountain it would be something in the mood of the islandtrack, that already belongs to STK.

Also I wanted to construct the track exclusively for STK >= 0.7 and the IrrLicht engine so that I can use the new possibilities like animations. Furthermore the track won't anyway be ready before STK 0.7.

To give you a little impression I modeled a part of the track in Blender and screen-captured a fly-through. It's one of the sections of the track that enters the mountain, leads through it and comes out of it on the other side. Sorry for the bad quality, but the model is so big, that blender doesn't display the whole mesh, so it looks like it is being loaded while flying through it.

It would be nice if you could give me feedback about how you think of my idea and if such a track has a chance to get accepted as an official STK track.

Also I would be glad if you could give me some more ideas about what else to include in such a track.

PS: Had to edit the post, because the forum doesn't allow Matroska-Videos, so I packed it into a zip-archive.

personally i think it's a great idea. and it would be nice to see a track take advantage of the new irrlicht features.

but it's a bit like the mines track..

I really like the idea. That cart is very coo, reminds me of my mines track (maybe a bit too much). If you use some nice textures, it will sure make it to the main package. I can't decide about that though

portets {l Wrote}:personally i think it's a great idea. and it would be nice to see a track take advantage of the new irrlicht features.

but it's a bit like the mines track..

It doesn't have to, with the right textures. Maybe you can add some jungle elements to the track. Or some signs of a lost ancient culture in the mountain (a lost temple), that would make it a real adventure track. What about some rolling rocks crossing the track?

Varivar {l Wrote}:I really like the idea. That cart is very coo, reminds me of my mines track (maybe a bit too much).

I hope the different setting of the track makes it clear, that this is rather an adventurous rollercoaster-like cart than a mining cart

Varivar {l Wrote}:Maybe you can add some jungle elements to the track. Or some signs of a lost ancient culture in the mountain (a lost temple), that would make it a real adventure track.

That sounds really cool! So I am going to discard the islandtrack like mood idea and rather concentrate on a more jungle-like feeling (though keeping the mountain or the cave or however you like to call it). Maybe inspired by Indiana Jones or Tomb Raider? Something like this?:



Of course not as detailed and complex as in this picture (then the track wouldn't be finished in five years ) but in a similar mood with lots of green and grey (plants and stones) and maybe a muddy brown driveline.

Varivar {l Wrote}:What about some rolling rocks crossing the track?

Or maybe a kind of scythe that swings over the driveline and will push your kart off the road when you don't look out?

I've still got a few questions:

• Is it for example possible to model a round plate that is part of the driveline and that turns around like a caroussel so that when you drive onto it you have to countersteer to drive straight?
  
  
• And I've got a problem with the texturing of the driveline. Either I prepare a texture for one short part of the driveline[1] (from one vertex to the other) and then it will repeat so heavily that it disturbs. Or I prepare a texture for a longer part of the driveline but then the UV unwrapping will get a real pain (especially if you want to change something sometime). Is there a trick to UV unwrap say the first ten parts of the driveline, texture them and then copy this texturing to the rest of the driveline (or selected parts)?
  
  
• I wanted to test the first part of my track to see if it is driveable or if I have to make it steeper or less steep. The STK Track Exporter works well and doesn't report a warning. But if I select my track in the game and click "Start Race" STK chrashes and gives the following error:
  
  

  {l Code}: {l Select All Code}

  ==== World : creating AI kart for #0===========
==== World : creating AI kart for #1===========
==== World : creating AI kart for #2===========
==== World : creating player kart for kart #3 which has local_player_id 0 ===========
ERROR: no valid starting position for kart 0 on track testtrack.

  
  But how do I define the starting point? I thought it was specified by the two free vertices at the beginning of the driveline mesh.

[1]: a prototype of the driveline texture is in the attachment (it would be nice if somebody with a little bit more experience could look at the prototype texture and tell if it is ok for a driveline texture or if the colors are too intensive or if it has other problems).

It reminds somewhat of the Amazonian Jungle road texture, so perhaps you could just re-use it and perhaps darken/lighten it a tad just for the variation.

DanielT {l Wrote}:

• And I've got a problem with the texturing of the driveline. Either I prepare a texture for one short part of the driveline[1] (from one vertex to the other) and then it will repeat so heavily that it disturbs. Or I prepare a texture for a longer part of the driveline but then the UV unwrapping will get a real pain (especially if you want to change something sometime). Is there a trick to UV unwrap say the first ten parts of the driveline, texture them and then copy this texturing to the rest of the driveline (or selected parts)?

http://supertuxkart.sourceforge.net/Ble ... g_tutorial

i wouldn't do the track like described in this tutorial. extruding a profile curve along the track curve has some limitations and the disadvantage that you lose the ability to conveniently edit your track after the necessary mesh conversion.

better use blender's array and curve modifiers. you can create a track mesh tile (which can be as long as you want if you have problems with repetition) that gets cloned along a curve (there is the option to automatically weld vertices where the cloned pieces touch). the track will stay fully editable. you can keep working on the track mesh tile and also on the track curve as long as you want. at the end you just will need some connection pieces to close the loop or connect different track parts.

in your case the whole cave could be part of a track mesh tile.

i have used this method for all my tracks (city, canyon, racetrack). you could check out my blend files.



EDIT:
http://www.gamasutra.com/view/feature/3 ... filter.php
...and this is an article about using the high pass filter for avoiding annoying patterns in tiled textures...

horace: sounds interesting indeed. sadly, none of the core developers are very good at blender. If you have too much free time on your hands, maybe you could add this technique to the tutorial

DanielT: you are using 0.7, right? I guess I will let Hiker answer to your problems since he coded that bit

Is it for example possible to model a round plate that is part of the driveline and that turns around like a caroussel so that when you drive onto it you have to countersteer to drive straight?

With the new IPO animation features, I believe it would be possible to make a large round plate that rotates. now, I guess no one ever tested what happens when you drive on that kind of thing, so it might be worth testing to see what happens

a prototype of the driveline texture is in the attachment (it would be nice if somebody with a little bit more experience could look at the prototype texture and tell if it is ok for a driveline texture or if the colors are too intensive or if it has other problems).

Indeed, as was suggested by someone else, feel free to reuse material from my old jungle track, if you think you can make a better track ^^

horace {l Wrote}:better use blender's array and curve modifiers. you can create a track mesh tile (which can be as long as you want if you have problems with repetition) that gets cloned along a curve (there is the option to automatically weld vertices where the cloned pieces touch). the track will stay fully editable. you can keep working on the track mesh tile and also on the track curve as long as you want. at the end you just will need some connection pieces to close the loop or connect different track parts.

Thanks for the tip, but that's the exact same method I used But me dumbhead forgot that I can use a longer part of the driveline as the base mesh for the array modifier instead of just one part.

horace {l Wrote}:http://www.gamasutra.com/view/feature/3 ... filter.php
...and this is an article about using the high pass filter for avoiding annoying patterns in tiled textures...

Thank you again, I'll read it immediately.

Auria {l Wrote}:you are using 0.7, right? I guess I will let Hiker answer to your problems since he coded that bit

Yes, I'm using the latest IrrLicht and STK builds out of SVN.

Auria {l Wrote}:Indeed, as was suggested by someone else, feel free to reuse material from my old jungle track

I am going to see if I can reuse it, but half the fun of making a track is painting the textures

I'm very happy to see another graphist

And it seem you're good so.
What is the version of blender you're using ?

rudy85 {l Wrote}:What is the version of blender you're using?

I use rather a selfcompiled Blender 2.5 than 2.49, but unfortunately the track exporter for STK is 2.4x only, so I have to use 2.49 for the track.

DanielT {l Wrote}:That sounds really cool! So I am going to discard the islandtrack like mood idea and rather concentrate on a more jungle-like feeling (though keeping the mountain or the cave or however you like to call it). Maybe inspired by Indiana Jones or Tomb Raider? Something like this?:



Of course not as detailed and complex as in this picture (then the track wouldn't be finished in five years ) but in a similar mood with lots of green and grey (plants and stones) and maybe a muddy brown driveline.

That would be very cool. Remember there's already the jungle track, so there should be a clear distinction between that track and yours.

Or maybe a kind of scythe that swings over the driveline and will push your kart off the road when you don't look out?

There are endless options. You could also make a trap, like a collapsing floor when you drive over it. This might be possible with physics, animations and a check line.

I've still got a few questions:

• Is it for example possible to model a round plate that is part of the driveline and that turns around like a caroussel so that when you drive onto it you have to countersteer to drive straight?

You can make a rotating carousel. The driveline, however,consists of static quads, but you can drag a driveline over the rotating carousel. I don't know how the ai would handle this. I somehow feel they will get lost on the carrousel...

And I've got a problem with the texturing of the driveline. Either I prepare a texture for one short part of the driveline[1] (from one vertex to the other) and then it will repeat so heavily that it disturbs. Or I prepare a texture for a longer part of the driveline but then the UV unwrapping will get a real pain (especially if you want to change something sometime). Is there a trick to UV unwrap say the first ten parts of the driveline, texture them and then copy this texturing to the rest of the driveline (or selected parts)?

First select all road polygons, then apply the road texture to them. Rotate the UV coordinates if needed. Most likely the texture will repeat heavily. So you have to divide the textures 4 parts (along the x-axis). Do the same with the road mesh (see attached picture). Apply the left part of the texture (1) to the most left polygon (1), do the same for 2, 3 and 4. Do this for all road polygons. Of course you could divide the texture in 8 as well if you have a longer texture. I hope this is clear.

The driveline and the actual road shape are two different objects.

I wanted to test the first part of my track to see if it is driveable or if I have to make it steeper or less steep. The STK Track Exporter works well and doesn't report a warning. But if I select my track in the game and click "Start Race" STK chrashes and gives the following error:

{l Code}: {l Select All Code}

==== World : creating AI kart for #0===========
==== World : creating AI kart for #1===========
==== World : creating AI kart for #2===========
==== World : creating player kart for kart #3 which has local_player_id 0 ===========
ERROR: no valid starting position for kart 0 on track testtrack.

But how do I define the starting point? I thought it was specified by the two free vertices at the beginning of the driveline mesh.

The starting position of the track has to bee at (Blender coordinates) 0,0,0. It should work then.

[1]: a prototype of the driveline texture is in the attachment (it would be nice if somebody with a little bit more experience could look at the prototype texture and tell if it is ok for a driveline texture or if the colors are too intensive or if it has other problems).

It's good. Nice and warm colors Now just make it tilable.

Varivar {l Wrote}:That would be very cool. Remember there's already the jungle track, so there should be a clear distinction between that track and yours.

Not necessarily, my old jungle track is not very good, if DianelT makes something better it can replace the old jungle track

Varivar {l Wrote}:The starting position of the track has to bee at (Blender coordinates) 0,0,0. It should work then.

Ah, thank you, that was it! The Point 0,0,0 was under my track mesh, so I had to pull it a little bit down the Z-Axis.

Now I was able to drive for the first time on my own track

I've got a question left:

In the video in my first post you saw a moving kart. I animated it with the "Follow Path" constraint in Blender and an IPO curve. Like described in the wiki I gave the kart the type "object" and the interaction "none". And the exporter exports the kart mesh succesfully to a .b3d. Unfortunately the kart doesn't move. Do I have to assign the IPO curve from Blender somewhere so the exporter knows about it?

DanielT {l Wrote}:

Varivar {l Wrote}:What about some rolling rocks crossing the track?

Or maybe a kind of scythe that swings over the driveline and will push your kart off the road when you don't look out?

That will already work with IPO animations. The reaction of karts being hit by this might be a bit too severe atm, but we are going to fix that.

Is it for example possible to model a round plate that is part of the driveline and that turns around like a caroussel so that when you drive onto it you have to countersteer to drive straight?

I never thought of something like that, and I am not entirely sure if this will work. You can model it with the current STK (well, minor problem: you would need probably a (very flat) cylinder for the platform, but that can be added easily), but I don't think that the kart will actually 'stick' to the ground (in the physics world IPO animated objects are kind of teleported from one position to the next, so friction wouldn't work) - though it might be worth trying. If we model this as a 'real' physics object, we would need some kind of engine that keeps the platform turning, and/or gravity 0 (if it's hovering in the air) - we would have to see what works best, and how to integrate this in the track exporter and stk. If you model this in your track, I can have a look if this can be done, but no guarantees (and it will be some time before I can get to this).
...

{l Code}: {l Select All Code}

==== World : creating AI kart for #0===========
==== World : creating AI kart for #1===========
==== World : creating AI kart for #2===========
==== World : creating player kart for kart #3 which has local_player_id 0 ===========
ERROR: no valid starting position for kart 0 on track testtrack.

But how do I define the starting point? I thought it was specified by the two free vertices at the beginning of the driveline mesh.

Yes and no - the two vertices specifies where the lap counting takes place, the actual start positions are not affected by this. And at this stage the track exporter does not have an option to specify the start positions, but you can (till I fix the exporter) add this manually:

{l Code}: {l Select All Code}

<start x="..." y="..." z="..." h="..."/>


WIth h being the heading, and xyz the coordinates. Most likely the start position is slightly under the track, causing the karts to fall down.

Cheers,
Joerg

Varivar {l Wrote}:You can make a rotating carousel. The driveline, however,consists of static quads, but you can drag a driveline over the rotating carousel. I don't know how the ai would handle this. I somehow feel they will get lost on the carrousel...

That might actually work itself out, since the drivelines will be static. So the AIs should recognise that they are point driving in the right direction, and adjust steering - in theory

Cheers,
Joerg

i also have a driveline question. does the the track have to be flat? or is something like a half-pipe possible?

horace {l Wrote}:i also have a driveline question. does the the track have to be flat? or is something like a half-pipe possible?

Yes, a half-pipe is possible. If I may oversimplify, drivelines mark the allowed x,y positions and the z direction follows from the track. That said, when a car is dropped onto the track, e.g. at the start or after a reset, the z position, so the z direction of the driveline must be approximately correct around the track.

Be warned though: there are still some issues with the physics engine. Since you are restricted to flat subsurfs, you cannot make a perfect curve. This makes the karts bounce around which, on some top-heavy karts like Wilber, can be impossible to control.

hiker {l Wrote}:If you model this in your track, I can have a look if this can be done, but no guarantees (and it will be some time before I can get to this).

Ok, then I will first build more of my track and ask again later.

Update:

I modeled the rest of the driveline and just have to finetune it a little bit. Is it ok if one lap takes approximately two minutes?
Also I'll post a screenshot of the minimap in one of my next comments.

And I modeled a maya/inka like pyramid, something like this:


There's still one question left that nobody yet answered:

How do I get my animations out of Blender? I'll just quote myself:

DanielT {l Wrote}:In the video in my first post you saw a moving kart. I animated it with the "Follow Path" constraint in Blender and an IPO curve. Like described in the wiki I gave the kart the type "object" and the interaction "none". And the exporter exports the kart mesh succesfully to a .b3d. Unfortunately the kart doesn't move. Do I have to assign the IPO curve from Blender somewhere so the exporter knows about it?

DanielT {l Wrote}:There's still one question left that nobody yet answered:
How do I get my animations out of Blender? I'll just quote myself:

DanielT {l Wrote}:In the video in my first post you saw a moving kart. I animated it with the "Follow Path" constraint in Blender and an IPO curve. Like described in the wiki I gave the kart the type "object" and the interaction "none". And the exporter exports the kart mesh succesfully to a .b3d. Unfortunately the kart doesn't move. Do I have to assign the IPO curve from Blender somewhere so the exporter knows about it?

The export script should detect and export the ipo curve automatically. The way that worked for me was:
Blender is set to an animation speed of 25fps. So set Blender to the first frame and place the cart at it's starting position. Now press I -> LocRot. 1 second later you want the cart 3 meters further on its track. So move Blender to frame 100 (25*4) and move the cart to it's new position. Now press I -> LocRot again. Continue this way to make the cart follow it's whole track. When you're finished select all curves and press E -> Cyclic. if you export the track now, the cart should be moving.

DanielT {l Wrote}:I modeled the rest of the driveline and just have to finetune it a little bit. Is it ok if one lap takes approximately two minutes?

It will be the longest track in the game, but if you make the track interesting to drive, I don't think that matters.

Varivar {l Wrote}:Blender is set to an animation speed of 25fps. So set Blender to the first frame and place the cart at it's starting position. Now press I -> LocRot. 1 second later you want the cart 3 meters further on its track. So move Blender to frame 100 (25*4) and move the cart to it's new position. Now press I -> LocRot again. Continue this way to make the cart follow it's whole track. When you're finished select all curves and press E -> Cyclic. if you export the track now, the cart should be moving.

I suspected something like that
The technique you described would be no problem if I wanted to animate for example the turning plate I mentioned above, but because the track of the kart is so complex (with curves and rotations and it goes up and down etc.) it would take hours just to animate a few metres. That's why I used Blenders "Follow Path" constraint. You just tell the kart to follow the curve and Blender does the ugly job. Unfortunately Blender doesn't convert this kind of animation to two IPO curves (position and rotation), but uses a so called "speed" IPO curve. Maybe I have to check in the Blender forums if you can convert the animation inside Blender itself.

Varivar {l Wrote}:It will be the longest track in the game, but if you make the track interesting to drive, I don't think that matters.

Maybe it takes so long, because I am not a very talented driver and have not jet distributed any nitro packs or speed lanes
I never stopped my time on the other tracks, but I doubt it was much below 1:50 (or 0:50? I have to check).

DanielT {l Wrote}:I suspected something like that
The technique you described would be no problem if I wanted to animate for example the turning plate I mentioned above, but because the track of the kart is so complex (with curves and rotations and it goes up and down etc.) it would take hours just to animate a few metres. That's why I used Blenders "Follow Path" constraint. You just tell the kart to follow the curve and Blender does the ugly job. Unfortunately Blender doesn't convert this kind of animation to two IPO curves (position and rotation), but uses a so called "speed" IPO curve. Maybe I have to check in the Blender forums if you can convert the animation inside Blender itself.

You can animate the cart in Blender with the "Follow Path"method. Once you've done with that, press I-> LocRot at every 25th frame. This way you might be able to convert the movement of the cart into Location and Rotation curves.

Maybe there is a solution too :



Then press alt+A




? did it works ?

Varivar {l Wrote}:You can animate the cart in Blender with the "Follow Path"method. Once you've done with that, press I-> LocRot at every 25th frame. This way you might be able to convert the movement of the cart into Location and Rotation curves.

Unfortunately this technique did not work. I think because the actual object (the kart) always remains at the position 0,0,0 and you just see it at an other position with the enabled Follow Path Constraint. After I had added all the keyframes and removed the constraint the kart remained at 0,0,0.

@rudi85:
Also your technique did unfortunately not work.

But nevertheless thanks for your efforts

I created a dead easy test scene. If you open the .blend in the attachment you will see a cube and a bezier curve. If you play the animation (Alt+A with the mouse over the 3D View) you can see the cube move along the curve. On the right side (wile the curve is selected) you can see the "Speed" IPO curve that belongs to the curve path. When you select the cube you can see that it has a Follow Path Constraint added and that it has no IPO curves at all. I hope someone can find a solution to the problem (maybe with help of this test file). If not I can still go over to a Blender forum and ask over there if it is possible to convert it.

DanielT {l Wrote}:I suspected something like that

Following a path is not supported by the current track exporter. I've done some work in the area, so I'd say there is a chance that it can be implemented, but there are some difficulties (e.g. I am not sure how the speed is determined - is it constant speed using the length of the path - if so, how do you compute the length of the path (afaik it can only be approximated), what about roll and pitch, and is heading always the direction of the path)? Some of those questions might be trivial - sorry, I am not an experienced blender user, but when I looked at the complexity of following paths, I decided to start with something easier like IPOs.

The code for exporting curves still in the track exporter (intended for camera curves), but even if the exporter would write the data, at this stage it is ignored by stk (you can try by giving the curve the type 'camera' - then something should turn up in the scene file).

If this is necessary (and it sounds like it is ) I am happy to try to get this to work, though that might take some time, since my todo list is already quite long.

...

The technique you described would be no problem if I wanted to animate for example the turning plate I mentioned above, but because the track of the kart is so complex (with curves and rotations and it goes up and down etc.) it would take hours just to animate a few metres. That's why I used Blenders "Follow Path" constraint. You just tell the kart to follow the curve and Blender does the ugly job. Unfortunately Blender doesn't convert this kind of animation to two IPO curves (position and rotation), but uses a so called "speed" IPO curve. Maybe I have to check in the Blender forums if you can convert the animation inside Blender itself.

If you could find a way of doing this it would be great, since it would save a lot of work But as I've said: I would be happy to give it a try, say in two weeks or so (realistically ).

Cheers,
Joerg

DanielT {l Wrote}:I created a dead easy test scene. If you open the .blend in the attachment you will see a cube and a bezier curve. If you play the animation (Alt+A with the mouse over the 3D View) you can see the cube move along the curve. On the right side (wile the curve is selected) you can see the "Speed" IPO curve that belongs to the curve path. When you select the cube you can see that it has a Follow Path Constraint added and that it has no IPO curves at all. I hope someone can find a solution to the problem (maybe with help of this test file). If not I can still go over to a Blender forum and ask over there if it is possible to convert it.

I've did a quick test: yes, if you give the curve the type 'camera', the curve data will be exported, though atm still to the track.xml file (and not the scene.xml file). There is still a lot missing, e.g. handling of the speed curve etc., but at least it's a start - though it doesn't help you atm

Cheers,
Joerg