Traffic with spline speed controller and 4wheeler extended

[mohment]

I'm trying to figure out a workflow for creating traffic using the 4wheeler extended and spline speed controller plugins. So far I have one car rigged and following a path with some waypoints that stop it for a couple of seconds and some that speed it up from approx 30mph to 45mph. Here are a few things I need help figuring out.

1. When I add more cars do I create a new carriage for each car that follows the spline, or do I link them to the other cars?

2. If I want some cars to drive down the same road, but some of cars to exit, or turn off that road, do I have to have a separate spline that overlaps the first one or is there another way to get a car to turn off? Would I turn off autonomous mode and drive the car manually?

3. Is there a way to have cars stop and go depending on the traffic? For example if I have an intersection of two splines is there a way to have a timed "traffic signal" that allows cars to go through automatically if the light is "green" and stop if the light is "red"? I guess my question is, are the waypoint attributes keyframable?

4. How do the waypoints work in regards to speed, if I have 3 waypoints, A B and C and the speeds are set to 30 60, and 30 does the car speed up from 30 to 60 and then back down to 30, or does it go 30 up to B and then start speeding up to 60 at that point? Please explain....

5. How do I determine the speed which the cars are travelling? I set the speed of the car to 45 and let is run its course, and went back and measured the time it took to travel a quarter mile and it was 8.9 seconds, or close to 90mph.

I haven't seen any animations with traffic in the examples, so if someone knows of any I would love to see how it looks and how they did it.

Thanks,
Jason

[Carl Buhre]

Hello Jason and welcome to our forum.

1. Additional cars,
If you're going to add more cars that are going to drive the same path as the previous car I would recommend that you link/parent the TargetMesh of the second car to the first one and have the second car drive with Autonomous Mode.
If you want the second car to drive along the same path but with different waypoints you will have to create another Craft Spline Speed-Controller and link/parent the TargetMesh of the second car to the second Craft Spline Speed-Controller's carriage.
And finally if you want the second car to drive along a completely different path you will have to create a new spline and a new Craft Spline Speed-Controller.

2. Have the second car drive away from a spline,
One way of doing this is the third option above, to create a new spline. But, you can also record the animation for the second car following the spline in Autonomous Mode up until the point where you want it to drive away from the spline, then you stop recording, go into the configuration window and disable Autonomous Mode and finally press Record and drive the car manually away from the spline.

3. Timed traffic lights,
You can create time delayed stop waypoints with Craft Spline Speed-Controller but you would have to time that yourself, the plug-in will not adjust to your traffic or traffic signals automatically.
As for key framing an attribute, it is not possible at the moment in the regular sense, only in the way that I described in the question above (#2).

4. How waypoint speeds work,
The carriage of Craft Spline Speed-Controller will adjust its speed to the waypoint that it just passed. So in your example, as it passes waypoint A, it will accelerate to 30, then as it passes waypoint B, it will accelerate to 60 and as it passes C, it will slow down to 30 again.
Keep in mind that if you don't have a waypoint at the start of the spline, the carriage will use the last waypoint's speed as its starting speed (as it is the waypoint behind the carriage (had it been a closed spline)).

5. How to determine speed,
If the value that you enter as a waypoint's speed is X, the speed will be: X meters per second.
Keep in mind that this only applies if the carriage is left unscaled! If you scale the carriage you will have to take that scaling into consideration in your calculation so I would not recommend doing so.

I hope this answers your questions. If you have more questions or comments you're very welcome to post them.

[mohment]

Thanks for the help, I've got it all figured out and have setup a configuration profile for the cars the follow and it seems to work. I'll share the settings and results when we are all done.

One other question I had was if you could have a carriage start at a location other than the start of a path? I have about 5 miles of highway that I am going to populate with cars and would like to stagger some carriages along the path to create "clumps" of cars driving. I could copy the path and delete the beginning part of the path, but I want to try and stay away from having too many paths on top of each other.

On a different topic, I see that Craft has pre-rigged models, but no cars? Have you considered adding some car libraries? MAybe some low and high poly collections.... Just a thought..

[Carl Buhre]

One other question I had was if you could have a carriage start at a location other than the start of a path? I have about 5 miles of highway that I am going to populate with cars and would like to stagger some carriages along the path to create "clumps" of cars driving. I could copy the path and delete the beginning part of the path, but I want to try and stay away from having too many paths on top of each other.

Yeah this is no problem, just put the carriage where you want it to start and press Record and it will snap to the nearest point of the path and go on from there. If you're working in Maya and have recorded it once, you will need to set a key frame for the carriage after moving it.

On a different topic, I see that Craft has pre-rigged models, but no cars? Have you considered adding some car libraries? MAybe some low and high poly collections.... Just a thought..

We've been very busy with development for other platforms among other thing so our library of pre-rigged models is still fairly small but it's not something we've forgotten about. I can't give out any dates or details but more is definitely coming. Thank you for the feedback though!

[mohment]

I've placed 11 cars all linked together and following a carriage along the 5 mile stretch of highway I mentioned earlier and the recording speed has dropped dramatically. Is there anything I can do to speed up this process? My plan was to have hundreds of cars driving through the scene, but if its taking this long to do 11, I am going to have to rethink my strategy. I have the high poly meshes of the cars turned off so only the craft dummy cars are showing. I'm working on a dual dual core 2.66 xeon workstation with 8gb of ram and a nvidia 8800 gts video card through windows xp 64. Any thoughts?

[mohment]

Do you know if anyone has had any success with proxy objects (vray or mental ray) and the craft 4 wheeler plugin? With so many cars in my scene I am wondering if I could use proxy objects and how that would work, and also how to set it up.

[Carl Buhre]

I've placed 11 cars all linked together and following a carriage along the 5 mile stretch of highway I mentioned earlier and the recording speed has dropped dramatically. Is there anything I can do to speed up this process? My plan was to have hundreds of cars driving through the scene, but if its taking this long to do 11, I am going to have to rethink my strategy. I have the high poly meshes of the cars turned off so only the craft dummy cars are showing. I'm working on a dual dual core 2.66 xeon workstation with 8gb of ram and a nvidia 8800 gts video card through windows xp 64. Any thoughts?

Are you working in Maya? Performance seems to decrease faster with more plugins in Maya than it does in 3ds MAX. But keep in mind that if you aren't changing any settings or driving path or your current vehicles, you don't need to re-record them. Just record the vehicle(s) you just added. But if you're going to have hundreds of cars you're probably going to have to use Resimulate overnight to create the animation.

[Carl Buhre]

Do you know if anyone has had any success with proxy objects (vray or mental ray) and the craft 4 wheeler plugin? With so many cars in my scene I am wondering if I could use proxy objects and how that would work, and also how to set it up.

I don't see any problems with using proxy object together with Craft Director Tools but that will only speed up the rendertime, not the creation of animation, unless I've missed some feature of mental ray proxy objects? We haven't tested it, so I can't say for sure but it should work.

[firetaw]

from my understanding of mr proxy. it reduces the amount of memory used in the max files. most likely this will improve the peformance of animating and simulating. what mr proxy does is it takes the geometry and caches it into an .mi files which is then referenced and used inside of max. the only down performance is when you increace the amount of visible vertexes that mr proxy caches. in other word after you create your mr proxy you can delete the geometry and it will use far less memory on your machine. this can be helpfull with craft, specialy with crawler tracks. it would be even posible to use high poly objects to simulate.