Hi guys. Just wondered what methods you track modders use for creating the elevation changes of a track. I'm interested in having a crack at it and have already started on a simple track for rf1, just to get my feet wet. But as a noob, I'm finding it quite difficult even after watching countless tutorials. Whilst searching youtube I stumbled across a video showing you how to import google earth images from sketchup into 3ds max along with the elevation data. https://www.youtube.com/watch?v=zzRYxSScQGk Has anyone actually used this method to create the terrain for there track?
In my point of view getting the right elevation changes is the biggest challenge of track making. By far! Anyway, as far as I see while browsing through Google Earth, there's no such level of precision in their elevation data that's useful for track making. At least, not for racing surface. Maybe you can import it and use as reference for the track's surroundings. You also should consider that the resolution of terrain varies from place to place, the same way as image quality also varies. Some guys use LiDAR data (when available), others just compare with photos and videos.
Have you tried CompeGPSLand? The precision is not wonder ful but for terrain is quite good. Google sketchup for terrain is also an option
Some of GE's terrain is quite perfect down to the metre, but in other places its really big. This is the road along the shoreline at Toronga Park Zoo in Sydney. Usually around major cities it is very fine as I believe GE used a helicopter with laser scanning to map it out. This is Columbus street circuit I started working on a while ago but other things came up in the way and I had to stop. But IMHO, something like this is good enough for a base to build a track on. There is a lot of un-needed polys after you import it from sketchup but multirez will do most of the work cleaning it up, then some manual tweaking. But the beauty of this is it also includes the buildings.
I think you should always check the accurancy of the GE data before starting anything. Sometimes it will be useful for both, rough track surface and surrounding terrain, sometimes just for this last one, and sometimes for nothing! Just to give you an example, in Sonoma, using the GE terrain will be worse for race surface than start from "nothing". Unless you're planning to build a roller coaster!
Yeah GE was no help at all for Sears, but with determination you can find things that will help you, like this video with an altimeter. Still not precise, but a lot better than what GE gave us. In the end, it just takes time and fine tuning, finding sim racers who have race on the track irl helps a lot with fine tuning too.
That's pretty cool! Great reference! Off-topic: Really? Driving a Corvette C6 on a track day holding the steering wheel like that?
Mianiak, how would you go about creating your track surface once you have imported your terrain mesh? Do you use spline/loft and then conform the track to the terrain mesh? I tried it this way but it doesn't give me the results I was hoping for. The resolution of the terrain mesh is pretty poor and no good for conforming a track to it, so I thought maybe a mesh smooth would give me a much better surface to lay my track on. This did work better but not perfectly. Is there a better way to seamlessly integrate the track mesh into the terrain mesh?
There are probably a few different way's, but the way I found to work best for me is to draw a spline over the imported mesh, just as if you were starting a new track and drawing the spline to an image or a plan drawing. Don't worry about elevations because this is just to be used to cut a centre line into the imported mesh. Then once that spline is done, extrude it down until the extents of it cover the up down axis of the imported mesh (ie so it cuts through it). Then select the imported mesh and clone it (for backup) hide the original and boolean the 'extruded spline' into the mesh, this should cut the centerline into it. Convert that to editable poly. Be careful here or it will take you forever to select every edge individually (it's a good idea to save the project file now). Go into edge submode. After the boolean it should leave the mesh with all the new cut-in edges selected, you might have to unselect some and select others, but be careful not to deselect them because as I said, it will take ages to reselect them all again. After you have made sure you have a full loop selected, click 'create shape from selection' Now you should have a spline that is precise to the imported mesh, from here you can make the track from that spline. In the end, for the track at least, you just using the imported mesh as a 3 dimensional guide. I highly recommend not using any of this mesh for the actual final model. Just use it as a guide. As for the terrain, create a new terrain from the track edges by using extrude push method as usual, then just shape it in 2d and conform it to the imported mesh once it's done. Try and have the edges follow the isobars of the terrain so when you conform it, it will sit nicely. The problem your going to encounter here is matching up the terrain to the track after you have conformed it. I found an easy solution to this,,, Ring select the edges next to the track and use connect to create an edge loop, then select the faces next to the track and detach them to a new object. After you have conformed the terrain attach the bit next to the track you detached before, edge loop select, ctrl + select vert submode and align then to z axis (or what ever is the up down axis, it might be Y), then weld them all together, they might not sit flush so 0.001 might not work, adjust the weld threshold until you see all the verts connected. Its going to look really weird now, but don't worry, that's all fixes in a few clicks. Go into edge submode and select an edge along the line you just welded, click loop select then hold down ctrl and hit back space, this will remove the entire edge loop and verts leaving you with a seamless connection to the track. Sometimes boolean doesn't like to work with single sided objects, if so you can do this to the 'extruded spline' Clone it. Select the clone and in poly submode, flip the faces, extrude it 0.0. Attach it to the original 'extruded spline'. Go to border submode, select all, hold ctrl and select vert submode, then weld the verts with a threshold of 0.001 (This will only weld the verts on the edges) This will basically leave you with a box that has no volume, but at the same time its a box and boolean will like it. I'm sorry if that's all a mess of words , I just started typing and didn't stop till I just about covered everything. If it is too confusing, let me know and I will see if I can make a short video demonstrating it.
WOW!! Thanks for the guide. I understand some of it but not all. I'll try to follow it as best I can and let you know how I got on.
NP, btw I just fixed up some spelling errors,, "After you have conformed the terrain attach the bit next to the track you detached before,"
Well so far so good but do you think I should stick with creating a track for rf1 or should I dive right in and make a track for rf2? The reason I ask is, I have my track spline ready to loft the cross section but not sure how many segments/polys wide to make the track.
Theoretically,,, Better off making it for rf2 because of the corners, if you make it high poly for rf2, you can easily remove edges for rf1, but if you make it low poly for rf1, then when you go to add edges for rf2, you will have 'square' corners. Realistically,,, Most systems these days that run rf1 and rf2 can handle processing the high poly track surface that rf2 uses. so I'd just make it for rf2 and leave it at that.
Ok rf2 it is then. But I've ran into a problem already. When I created a shape from the edges, that will be used for lofting the track, is now an editable spline. When I select that shape and click on loft, only "get path" is selectable. "Get Shape" is greyed out so I cant use my cross section for the loft. Have I done something wrong?? Also, how many polys wide should I make the track. Sorry for these noob questions but I've spent days trying to get past this stage.
Ummm,,, I have had this before, but I clicked so many things I can't remember what fixed it . Try make sure that every vert in the spline is welded together. Then reset xform and convert to editable spline. I'm not really a loft person, I prefer to extrude, so maybe someone who lofts might have a better idea. 8 is a good medium. But keep in mind that with the loft you can add in sections too. So lets say the resolution of the data is 1m, then make the distance between verts in your shape and spline 1m. but if the data is say 3m, then you only need to make the distance 3m and use the loft to add in extra sections, this saves processing resources from being used up where they aren't needed.
Your basic spline probably isn't a proper, single-spline loop. Some vertices of the spline are likely split up, causing it to have several sub-splines, which Loft can't handle.
I haven't done this for nearly 2 years now but from memory, I believe you will have to weld the spline vertices and then it should work when you loft it with the cross section shape.
If anyone would be willing to make a short video to demonstrate making the infield/outfield using extrude push method I'd be very greatfull. Especially when it comes to hairpins.
