So I'm banging my head on a wall here. I've been trying to find how minecraft handles rain and the way it interacts with blocks but I'm not having any luck. I'm overriding getCollisionShape and I want to set it to empty for rain because it causes loads of lag(I go from 200+ fps to 1) with my custom model and its not a full block anyway so I wouldn't want it to stop rain from passing through anyways.

 

Also setting the block to not have collision does indeed fix the problem but then entities like players, falling blocks, and mobs would just pass through which is also not what I want.

Edited July 24, 20223 yr by Will11690
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Welp after a short break I came up with this

@Override
    public VoxelShape getCollisionShape(BlockState state, IBlockReader reader, BlockPos pos, ISelectionContext ctxSupplier) {
    	
    	if(ctxSupplier.getEntity() instanceof LivingEntity || ctxSupplier.getEntity() instanceof FallingBlockEntity) {
    		
			return this.getShape(state, reader, pos, ctxSupplier);
		}
		return VoxelShapes.empty();
	}

That kills rain interacting with any of the voxel shapes I'm drawing and removes the lag almost completely. It ain't perfect but it works good enough. There still some weirdness with the AI of mobs when they walk on it(Don't move/spin around) and using a spawn egg on top of it causes the mob to spawn inside the block. I'd love some advice to fix if its even possible.

Edited July 25, 20223 yr by Will11690
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18 hours ago, diesieben07 said:

The thing that matters is Heightmap.Types.MOTION_BLOCKING. This determines the point at which rain "hits the ground". This means that the Material for your Block needs to have blocksMotion return false. Unfortunately setting this to false will probably have a bunch of other side effects.

Yeah, after looking into that and playing around with it(basically that'll make the block act like a plant and things like that which without making a big, ugly, messy hack determining what things its solid for) I came up with another solution that may also work to fix my lag issue. Right now my block has 12 possible block states with 6 of them having kinda complex voxel shapes(they are pipes and draw different connections based on the block they are next to) so I am thinking that I should move a bit of functionality to a block that most likely wont have 1000 of them at any point in one chunk. Doing that I can reduce my blockstates to 6 and remove the complex voxel shapes. If that doesn't clear it up then I will stick with my current "Hack" and just live with the slight weirdness that comes with it. I did discover what causes the weirdness in mob behavior though, since the blocks are basically only solid when a Entity makes contact with them the AI doesn't see them as valid paths so they just stick to where they are.

It's sad how poorly this game holds modders in mind when they say they fully support them lol. Like the whole locking fluid physics behind the water and lava tags and making fields related to it hard to work with, it irritates me to no end.