Faucets and Filters

Hopper pipes push items into the block they face, and a black arrow on their side shows that direction. Placing one defaults its face toward the player, and holding Shift while placing lets the player choose the block it attaches against. Filter hoppers follow the same placement rules and also face a direction, pulling from the block behind them and pushing into the block in front.

A filter hopper has two inventories: a top inventory for the items it allows, and a lower filter inventory that sets which items may pass. Items may pass only through the side that matches the filter. When powered by redstone, a filter hopper switches to blacklist mode, so items matching the filter are blocked while everything else passes. Collection is limited to item entities above the hopper, since gravity sets where they fall from.

Faucets draw from inventories in the blocks directly behind them and spew items onto the ground unless powered by redstone. Switching the faucet reverses this behavior, so it spews only while powered. A solid block in front of a faucet stops the spewing, and the faucet keeps drawing from the inventories behind it. The mod adds three new blocks to the game and runs on client and server, so both the server and every player need it. It is published for Forge only, for 1.10.2, 1.11.2 and 1.12, under the Creative Commons Attribution Non Commercial 4.0 license, and it is not open source.