Got NPE when tried to disable plasma wall:
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x6dc00b]
goroutine 12457 [running]:
main.(*game).checkPlayerInteraction.func3()
/home/sedyh/projects/go/magrix/main.go:497 +0x6b
created by main.(*game).checkPlayerInteraction
/home/sedyh/projects/go/magrix/main.go:488 +0x1ae