Friction maps

[Shadow]

Jlv I remember you saying something that friction maps are working on this game. So, is there a way to make them with the current track making tools we have? I'd like to test different frictions for my track and their effect on cornering/riding.

EDIT: scratch that, didn't read that one post thoroughly. Right now I only need to know the dirt's default values and what exactly does the rolling resistance do?

[jlv]

The defaults are:
friction 1.0
low roll 5
high roll 15

The rolling resistance is in pounds. Low is for when the tire is not compressed at all, high is for when the tire is down to the rim.

[rewrew421]

can you explain this a little more jlv?

[Netdemon01]

Open up 'texturelist' in a text editor. See the second line down that says "1 20 50 grass.ppm" ? Those are changing the default values for the grass to have a coefficient of friction of 1.0, low pressure rolling resistance of 20 and high pressure rolling resistance of 50. Add some values in front of dirt.ppm to change the dirt.

[rewrew421]

Yea, i understand this but is there anyway to make just certain parts of the dirt have certain properties?

[jlv]

I think what you want is to create a new tile. Add a line like ".5 20 50 mud.ppm" and you will have a new slippery mud tile. If you want to do a nice job, you'll have to also create the tiles to join the dirt tiles with mud tiles. This is kind of complicated. You have to create tiles named dirt-mud-0001.ppm to dirt-mud-1111.ppm.

Each digit in the number represents a corner of the tile. The first one is the top left, the second is the top right, the third is the bottom left and the fourth is the bottom right. So...

dirt-mud-0001.ppm would have mud in the bottom right and plain dirt everywhere else.
dirt-mud-0010.ppm would have mud in the bottom left and plain dirt everywhere else.
dirt-mud-0011.ppm would have mud in the bottom half and plain dirt everywhere else.
dirt-mud-0100.ppm would have mud in the top right and plain dirt everywhere else.
dirt-mud-0101.ppm would have mud in the right half and plain dirt everywhere else.
dirt-mud-0110.ppm would have mud in the top right and bottom left and plain dirt everywhere else.
dirt-mud-0111.ppm would have plain dirt in the top left and mud everywhere else.

The rest are the same but with mud in the top left.

[rewrew421]

Ok so like the top right will be a mud bog and the rest will be normal? Theres no way to paint "mud" here and "dirt" here?

[jlv]

The track is a 512x512 array of tiles. Once you have the new tile type, you will be able to put it anywhere on the track.

Here is a simple mud tile example. Notice how the tiles don't join up correctly. That's what dirt-mud-0001.ppm etc would fix.

[rewrew421]

Meh, JLV it might be just me but i really think you might wanna rethink this texture thing. It works great but it really is complicated(to me atleast). But im old school and kinda used to the friction maps and textures of MXvATV, MCM and rigs of rods. RoR dont have friction maps(yet) but it uses 1025x1025 textures in jpeg format would that not be aplicable here?

Just suggesting not complaining

[jlv]

I do intend to ditch the tiled texturing. I think I should be able to make something work that lets you place textures on the terrain with arbitrary scaling, rotation and blending. The only downside should be a less even framerate.

For the friction map, it seems like an advantage to go through the texturelist. That way I get to set friction and both rolling resistance settings without wasting 3x as much memory on individual arrays for friction, low roll and high roll. Also, in the future I may want to expand it more. For example, just using one value for friction is a little lame. To do a perfect job you would want a full traction curve that would give you the correct friction for each pressure and slip rate. It might also be a good idea to make the roost change depending on the soil type too. All that would just be extra fields in texturelist but with a friction map it wouldn't fit in at all.

[rewrew421]

Yea i agree, i was just thinking a little more on the subject and i thought that the current idea might work but instead of one value being dirt, have 4 or 5(or more) different shades/types of dirt and then inthe texturelist have dirt1 1 20 50 dirt2 1 20 50 and so on and then for each track you could edit these values lto your likeings or the tracks preferences like we have now. Im not sure if this would work but i thought i'd put it out there.

[Wilson]

Makes sense because as of now theres no difference between tracks right now. Theres not much freedom right now with tracks.

[Garasaki]

Hello, I'd like to dig this out of the grave...

JLV's example here is a bit confusing, because the track name is the same as the dirt name he used.

I am having trouble adding new tiles to my track. I suspect the problem is in how I'm naming my new tile, as it dosent show up in the editor and I get a message about not being able to find the .ppm when I load the track up.

JLV's example says

0.5 20 50 mud/mud.ppm

Ok, I get the numbers, I get the filename mud.ppm is a power of 2 picture file, located in the track folder.

Whats the mud/ part? Does that need to be the track name? Which is what I have it as, but it dosent work.

I also wonder if it simply is a "name" that's sort of arbitrary. But then why wouldn't my game be finding my .ppm's...?

Any clarification on adding tiles to the texturelist would be awesome...

[wheels1758]

if the file says mud/mud.ppm, the game will search for that tile in your personal folder, in another folder called mud. What i suggest: put mud0001.ppm through mud1111.ppm in your personal folder, and change the texturelist code to say mud.ppm. That way it will look in your personal folder for the mud tile.
Another thing that will work, especially if you dont actually release your mud tiles, is to put the tiles in your track folder and change the code to say @track/mud.ppm. Let me know if that made any sense.

also, are all of the .ppm's in a folder called mud? if so, you would need @track/mud/mud.ppm

[Garasaki]

Ok (hey sign into MSN)

So the @ is req'd right?

Cause I tried it that way and it didn't find them.... (that is, I tried @track/mud.ppm)