Non-jumpy driving mesh

[HeathcliffMontague]

I know this has been discussed in the forum before, but based on my searches it hasn't quite been resolved, it seems. I've managed to import some straights that are very smooth to drive on. Put one after the other and you won't even notice crossing from one to the next, even at very high speeds. I even imported them using  the LL importer/physics options, and they still work.

Corners are a different story, they are jumpy no matter what. Just how jumpy seems to depend on lag. Having finally figured out how to get a straight road texture to follow a mesh curve, getting said mesh texture ready and align friendly and getting the curves down to 2-4 LI (sides vs. not), whether convex hull or prim, my curves still might make you fly off the track. Even a simple structure like this.

 

(Blender is a steep learning curve for me. Even the above "sectioning" took a lot of time).

I've tried importing a very simplified version along with it as a physics model, but it remains jumpy. Any tips or pointers to relevant tutorials (there are tons of tutorials, but not directly relevant to this that I've found) would be appreciated. I've probably skipped a lot of steps here,.

[Wulfie Reanimator]

What does your physics model look like, and how is a simple shape like that 2-4 LI? What settings do you use in the importer exactly?

[HeathcliffMontague]

My "physics" (if you can call it that) model was just what you see in the pic, but just very plain, no faces or anything. All "white" in any Blender view. One face. "From File" in FS doesn't give a lot of options.

For my straights I used Firestorm LOD high.

[Wulfie Reanimator]

5 minutes ago, HeathcliffMontague said:

My "physics" (if you can call it that) model was just what you see in the pic, but just very plain, no faces or anything. All "white" in any Blender view. One face. "From File" in FS doesn't give a lot of options.

For my straights I used Firestorm LOD high.

In that case, I would suggest removing the two loops going through the middle of the road (lengthwise) and possibly some of the loops going across the road.

Without being able to inspect all the physics models (especially if you autogenerated the staight pieces), I'm also assuming that the main surface of the road is perfectly flat.

Generally speaking, you would want to make sure the physics models line up EXACTLY and for that reason you should create them by hand, even if (and because) the models should be simple cubes. You could probably get away with even the curves using a square physics shape.

[HeathcliffMontague]

I'll try that, thanks!

[arton Rotaru]

1) Make sure your road models are larger than 0.5 meters in any dimension. Including the Z axis.
2) Use a triangle based custom physics mesh with open edges during import. (Do not hit the Analyze button.)
3) Set Pyhsics shape type to Prim.
4) Let us know if this worked for you.

 

 

Edited January 24, 2019 by arton Rotaru

[animats]

What are you using as a vehicle base?

Physics model of one of my bike bases. This handles rough terrain well.

SL doesn't do wheels. Everything slides. So the base of your vehicle must slide well over minor obstacles. A hull-like surface with all convex edges is a good choice. I use a mesh ellipsoid flattened out into a pancake

There are some serious bugs in the physics system. Notably:

• There is a minimum physics weight below which the physics system will not work properly. If I configure that bike so the only part with physics is the base, it will not slide well. I have to enable a physics model for other irrelevant parts before sliding will work.
• A break angle at a hill of 18 degrees or greater will "trip" a vehicle and it will go sideways suddenly. There are three places on Heterocera main roads with that problem.

Also, if you're road-building, remember that you must provide a few meters of support beyond the edge of a sim, from each side off the edge to the other side. Otherwise, vehicles will sink into the ground as they lose support from the sim being left. (A few vehicles compensate for that; my bikes do, and Christi Charon has a "magic" trail bike that does.)

[Kyrah Abattoir]

Concavity creates a "response" point when a physical object slides over it. That's perfectly normal with rigid bodies. Real world vehicles have suspension systems specifically to dampen those responses (picture an all wood wheelbarrow hitting a pothole at speed).

[HeathcliffMontague]

Animats, I don't build bikes, but I have lots of them. DM, IK, JFC, BGC, Moto Bazzi, The Legend bikes, TC... Too many to mention them all. The vehicles aren't really an issue here, as they all work perfectly on other roads.

I think what I really need to look into here is the physics shape, as others have suggested with helpful tips. Another learning curve, but I'll get there eventually.

[HeathcliffMontague]

On 1/24/2019 at 9:35 PM, arton Rotaru said:

1) Make sure your road models are larger than 0.5 meters in any dimension. Including the Z axis.
2) Use a triangle based custom physics mesh with open edges during import. (Do not hit the Analyze button.)
3) Set Pyhsics shape type to Prim.
4) Let us know if this worked for you.

What you suggested works. For the most part it works very well, so thanks for that. Increased them to 1 m in height, and that works even better. I can drive for laps and laps on end with no problems, very smooth, with most "reasonable" physics vehicles, but sometimes I just "hit a wall" which feels like hitting an invisible prim when entering the corners (and no, there are none there :)). I turn around and try again, and it works just fine most of the time. Especially with more sloppy driving I seems to hit that "invisible wall", with a "sharper" driving style it usually works very well.

I have no plans on making any roads for the MP or anything like that right now - unless I feel I get it just right, then I might build something and if the driving experience is right just *maybe* make it public in some way or form. Just making stuff for myself and friends to drive on just now.

Just happy that I've managed to create a (98 %) driveable road for the time being. I'm in no hurry, thanks for the tips all.

 

 

[Aquila Kytori]

A while ago I made a sim size stadium race track.

At an early stage while testing the banked track we found that when using a copy of the High LoD track for Physics (the pink part in the first screenshot) the surface felt quite bumpy.

When extra edge loops were added to the Physics mesh the surface became smooth. I don't understand why this (smaller tris in the physics model) smoothed out the surface but it did. Its the only time I have ever had to have more geometry in the Physics mesh than the visual mesh.

The finished track had 4 extra edge loops along both curves and straights. So maybe something you could try

 

 

 

[HeathcliffMontague]

I now understand much better why many builders do this:

Made driving physics much better for me. But I'm not a fan of it. In-world objects should be, for lack of a better word, at least somewhat "tangible".

 

Edited March 6, 2019 by HeathcliffMontague