Minecraft – Test to see if chest minecart has specific item

I had to end up using another method to get the tp home functionality to work. The tp home link in the book now teleports the player to just above an End portal, which then teleports players within a radius to just above the portal out of the End.

I had to also create an end portal in the Nether at the same co-ords as in the Overworld (which you can do - forums were unclear about this), so that the same functionality still works in the Nether.

The set home link in the book now sets the players spawn point. So, if they die or tp home (tp to end portal then tp to portal out) they'll end up back at their home.

Hope this was helpful to someone else with the same issue.

This method is also a fairly bad kludge and a bit impractical, but it should be able to detect block light as well as sunlight.

There are a few of processes that only occur at certain light levels, sunlight or not:

Event            || Light Level
================================
Snow/ice melt    || >=12
Mushrooms uproot || >=13
Flowers uproot   || <=7
Plants grow      || <=9

With a very high /gamerule randomTickSpeed, these processes can happen almost immediately. Obvious disadvantage here is that the gamerule will also effect the processes throughout the entire world.

Different mobs also have different spawning light levels:

Mob              || Light Level
================================
Bats             || <=3
Most hostiles    || <=7
Blaze/silverfish || <=11
Most passives    || >=9

You can also create custom mob spawners will spawn a mob every tick by changing its MinSpawnDelay and MaxSpawnDelay.

Using either of these methods (or both), what you'd need to do is something like:

1. Clone blocks around the block/player to a specific area
2. Set the block/spawner in the middle of the newly cloned area
3. Wait a few ticks
4. Test if a mob has spawned, or a process occurred

You could also have the mob spawner (minecart) or test block at the actual player's location, rather than cloning it first, which would reduce lag a lot but cause the player to see flickering mobs/blocks.