Review the `collisionMask` passed to `rayCastClosest(..)`

[gavanderhoorn]

The current collision mask is set to:

https://github.com/tud-cor/FS19_modROS/blob/5e8d48482b79c9608f7fdbe42f88f7e7ef0bc568/modROS.lua#L92-L98

IIRC, we've not been able to really find any documentation for those bit positions, except in this article/tutorial: How to Set Correct Collisions in Your Farming Simulator Mod:

Bit	Feature
1	non_pushable1
2	non_pushable2
3	static_world1
4	static_world2
6	tractors
7	combines
8	trailers
12	dynamic_objects
13	dynamic_objects_machines
20	trigger_player
21	trigger_tractors
22	trigger_combines
23	trigger_fillables
24	trigger_dynamic_objects
25	trigger_trafficVehicles
26	trigger_cutters
30	kinematic_objects_without_collision

I suspect these are documented somewhere, I just haven't searched for it.

Whether the current value of the collisionMask is the optimal value for our purposes would be something to discuss.

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Edit: from the same page: some example collision masks for various objects/vehicles:

Collision Type	Bits	Hex Value	Decimal Value
Tractor	1, 6, 13, 21	0x202042	2105410
Combine	1, 7, 13, 22	0x402082	4202626
Fillable	1, 8, 13, 23	0x802102	8397058
Cutter	1, 12, 13, 24, 26	0x5003002	83898370
Tools	1, 13	0x2002	8194

[gavanderhoorn]

@Sagexs: it would be very helpful if you could experiment a bit and see whether any of these bits (or perhaps some of the undocumented ones) make raycastClosest(..) also detect vegetation.

I do expect there to be a rather large performance penalty if it would be possible, but at least then we'd know.

@tckarenchiang: perhaps we could see whether we'd want to make the collisionMask configurable, so users who have a need could tweak it for their specific use-case.

[gavanderhoorn]

Oh, and AFAIU: if collsionMask is not set, it will default to hitting everything.

[tckarenchiang]

Oh, and AFAIU: if collsionMask is not set, it will default to hitting everything.

I've tested: if collisionMask is not set, crops still can't be detected (with laser scanner pointing down)

[gavanderhoorn]

And just to make sure: if you set all bits of the collisionMask, does that change anything? So set it to 0xFFFFFFFF.

I'm not sure where I read that not providing collisionMask equates to a fully enabled collisionMask.

[tckarenchiang]

And just to make sure: if you set all bits of the collisionMask, does that change anything? So set it to 0xFFFFFFFF.

It doesn't seem to change anything.

[gavanderhoorn]

Ok, then it seems we can close #10 for now with the unfortunate conclusion that raycastClosest(..) cannot be used for detection crops/vegetation.

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Edit: perhaps if we make some progress with #22, depthimage_to_laserscan could work for that instead.