This part just introduces you to the 2 tools Holes and Impassible.
There is not much to learn about them. Only that they exist and for what they are
Holes
Holes are needed if your player should be able to get under the ground. You need it for caves or buildings.
Also you can create partly groundless maps with this tool.
>> Select the holes tool, its the icon with the glowing tube or press 4.
>> CTRL + left click open a hole.
>> SHIFT + left click close it again
Holes are set on subchunks. That are the blue squares you only see if you have lines turned on (F7) and holes tool selected.
Impassable
You can activate the option so that the player can't pass chunks. It's like an invisible wall.
You can use this to prevent the players from entering regions you don't want them to enter or just create a barrage in the sea.
>> Select the Impassable tool, it's the last icon with the spiderweb on it or press 6
>> SHIFT + left click turns it on
>> CTRL + left click turns it off again
Activated chunks are marked white.
This guide has been completely proof-read and corrected in grammar by Mountainlion. Feel free to message him.09 - Water script in deepth