Fixed Gen Directionality Bug and Minor Tweak
Fixed Gen Directionality Bug and Minor Tweak

I fixed a subtle bug in RiftGenerator. The code for picking random
coordinates on the surface of a chunk would subtract a random amount
from the coordinate of the chunk's corner. Unfortunately, subtracting
meant that we would almost always generate coordinates OUTSIDE the
intended chunk. The correct calculation was to add, not subtract. This
meant that if you walked in a direction in which our gateways were
generated outside of existing chunks, then their data would be lost and
no gateways would generate!

To reproduce this bug, max out the chance of generating gateways and fly
in the direction that decreases X and Z. You must fly into new chunks.
After passing the gateways produced when you spawn (if this is a new
world) you'll see that gateways don't generate on the landscape.
However, if you change directions, they'll begin generating again.

In addition to fixing that bug, I also tweaked all the block setting
calls in RiftGenerator so that they'll trigger block updates and send
update packets to the client. I think triggering block updates will
prevent unusual problems with floating sand, gravel, etc.

Zandorum/DimDoors,CannibalVox/DimDoors