New to Phoenix, looking for some advice on a car shot.

[matt_foxfuelled]

Hi Folks, I'm relatively new to Phoenix, I'm trying to add some smoke off of the tyres on a shot where the car is drifting around a long corner. When I add in smoke, the container size is huge (but still not big enough). As the camera is behind the car, ideally the container doesn't need to be big, if it can 'move' with the car. I think the speed of the car and the length of the shot (150 frames) are partly to do with it, but most importantly, I just need to limit the effect to near the car.

Any advice on how to get this set up would be appreciated.

Thanks
Matt

[georgi.zhekov]

Hey,

Can you show us how the car moves?

Maybe the adaptive grid can help you expand the grid only when needed? You can find more about it here - https://docs.chaos.com/display/PHX4M...d-AdaptiveGrid

You can also check out this video as well? https://youtu.be/lTxD0xNVIyo

[matt_foxfuelled]

Hey, Thanks for getting back to me,

Unfortunately, the car model is under NDA. So I've grabbed a shot of the scene which doesn't show very much!

But you can kind of get an idea of the scale of the car and the distance it travels, and of the Phoenix system.

It's a semi-circle track with the car 'drifting' around it. It does the full semi in 150 frames. I've been using Large scale smoke sim as the starting point.

But the problem is when it's initially set up, the sim cube doesn't cover the distance the car travels, in fact, it covers about 5% of the distance. I've tried setting the Adaptive grid to all settings but no joy.
Now the thing is, as the camera is behind the car, it doesn't really matter what happens '20m behind the car' as it's off-camera. So I didn't know if there was a way to parent the sim to the car root control (or something like that)?

The second issue is that because the car moves so fast, the sim kind of puffs out spurts. I'm guessing this one is down to how many sub-frames I calculate over?

I feel like I'm just being an idiot here...

Any help greatly appreciated!


Matt

*note: I'm in Maya not Max

[Svetlin.Nikolov]

Sure, you could parent the grid under the car geometry - by default the grid will react properly to the inertial forces.

And, as Georgi mentioned, combining this with the adaptive grid should do the trick - you just need to be conservative with the Adaptive Grid Threshold and let it cut off some of the smoke so the grid does not expand too much to unmanage-able sizes.