Map Reveal Tool. Adds a shortcut selector tool to reveal (or hide) the selected section of the map.
Click the Map Reveal Tool and make a selection area to reveal a section of the map.
Hold Shift while making a selection to hide a section of the map.

Warning : This mod forces the game to generate any un-generated chunks selected and can drastically increase the size of your save.

Special thanks to Ore Eraser by CaptainWHot : https://mods.factorio.com/mod/OreEraser for reference on setting up the selection tool.

Feel free to modify or update this mod as desired.