It was for my server. I was looking for a way to allow visitors that don't have minecarts to visit the world faster by using Minecarts on previouly created railways. It's usefull also for players who build rollercasters.
I add (a white) Horse and Boat recently, to freely visit the world and oceans.
Minecarts, and living entities cost a lot of server consumption. I don't want that players create loads of minecarts to use railways. And on an economy server you can't give minecart to player without impact on the economy. Horse is rare. Autohoses diseapers as soon as you live them.
Crafted Minecart are not destroyed when players left them. So they can be used as usual. Same rule for the horse, and the boat.
Minecart :
Simply click on the rail (or powerred rail)
Horse, Boat and Minecart :
Use the command
/autominecart <horse|boat|minecart> <playername> <velocity_x> <velocity_y> <velocity_z>
Use the command with a command block :
for example : throw the player in the air in a boat in the x direction. If he falls in the water, the player will deal no damage ;-)
/autominecart boat @p 2 2 0
Teleport
Teleport a player with his vehicle (minecart, horse or boat)
/autominecart tp <playername> <world> <x> <y> <z>
Test if a player is riding an autominecart
public boolean isAutominecart(Vehicle vehicle)
Tp an autominecart
public boolean tpAutominecart(Vehicle vehicle, Location location)
Join my server, rails, horses, and boats are in front of the spawn : BlocksAndGold Minecraft Server
A short Video : http:youtu.be/UP86UnIZCcU

here : http:dev.bukkit.org/bukkit-plugins/autominecart/files/
Please report if you find some !
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