"Fake" collision that can be detected by RaySensor but doesnt collide with other models?

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Hi,

I'm trying to implement some kind of particle system to generate sensor data that look like the sensor is in a smoky or fogy environment. So i implemented a plugin to spawn one model with 3000 tiny collision boxes with random location's. The data's look good so far, I'm planning to move the collision boxes that it look's like real noise jitter.

The Problem is that the "smoke" model also collides with other models. Is there a way to get rid of that?

I know that there are probably more efficient ways to implement this and in the next month i will spend some time on this problem. If someone could give me some hint's i will start to work on that.

Greetings Alex