What is blockParticleGravity used for?

[Mctittles]

I was looking for a low overhead way to "mark" a bunch of placed vanilla blocks and I started looking for public variable I could change so I don't have the added space of a bunch of titleEntities. 

 

I ended up finding every block I checked had blockParticleGravity set to 1.0.  Changing it to .9 allows me to keep track of which blocks I marked and so far has not caused any problems.

 

But, I want to make sure I don't break anything by modifying this variable.  When is this variable used, and will setting it to .9 break anything?

[Mctittles]

Perhaps nothing?

 

Sorry, I'm not familiar with Set<Block>  .  Where is this?

[Mctittles]

Oh wait you are referring to a hash or list type thing.  Sorry, coming from C/C++ so don't instantly recognize the terms here .

 

The reason I am trying to modify variables of the block instead of just saving them in an array is because I want this to be persistent with map saves etc. 

 

Basically I want the players to be able to use a wand to mark an indefinite amount of blocks that will change how things spawn on them while using as little overhead as possible.

[Mctittles]

Currently I'm tying it to the block that is on the ground.  This is all in an effort to make it so I can use light switches in my house without coming home to a room full of zombies.

 

So I came up with the idea of being able to use a wand or something to mark all blocks you don't want zombies to spawn then cancelling the spawn on those blocks.  Since this could potentially be a lot of blocks tying it to the player might result in a rather large array, so that's when I started looking for alternatives like looking for existing variables on blocks I can change to use as a reference.

[Mctittles]

Oh bummer.  Well, that's disappointing .

 

I suppose maybe I could make some sort of object you place that has a range and within that range you mark your blocks and the marked blocks are stored in the object.  Lot more work than I was hoping, but could work...

 

Thanks for the help!

[Mctittles]

I guess I wouldn't know how to save the set with the map though.  Seems like I'd have to use a tileEntity somewhere to keep track of this information right?

[Mctittles]

Thanks I'll look into WorldSavedData.