adding randomness can cause weird behavior

[cho3]

• generated cars can be going too fast to no hit cars in front
• normal noise on accelerations can also cause similar things

[zsunberg]

Yeah, we need to use distributions that have limited support.
Cars should not brake faster than phys_param.brake_limit
There should also be a physical acceleration limit.

The noise on generated cars velocities should be small. Were you talking about the initial scene generation or regeneration?

[cho3]

more for car regeneration--I think because in initial scene generation, it's enforced for there to be more space rather than less.