Description
Do a hit test between two positions.

Arguments
StartX The starting X coordinate.
StartY The starting Y coordinate.
StartZ The starting Z coordinate.
EndX The ending X coordinate.
EndY The ending Y coordinate.
EndZ The ending Z coordinate.
Flags The hit flags. 0xFFFFFFFF is everything.

Returns
X The X coordinate of the hit, or nil if no hit.
Y The Y coordinate of the hit, or nil if no hit.
Z The Z coordinate of the hit, or nil if no hit.