Bang Commands

“Bang commands” (called such because they start with a bang “!”) are used in Smelt to implement powerful custom commands. Some are built into Smelt, others can be added using the plugins feature.

Built in commands

Initial command

The !init command

Usage: !init <command>

This command is used to define commands that should be executed when a module is installed, but don’t need to be included in the command blocks or executed again later. To re-execute the commands, the module would have to be reinstalled.

!init say Installing Module

Note: The <command> parameter must be a vanilla Minecraft command and cannot (yet) be a nested bang command. The leading slash “/” on the Minecraft command should not be included.

Loops and events

Explanation

Commands for loops (20-ticks-per-second continous commands) and events (run-once commands) are built into Smelt. These bang commands require the bang-commands-setup.mcc module to be installed into your map. You will be prompted to do this by Smelt when using them.

The custom commands use Minecraft’s scoreboard tag feature to work. The setup module created an entity named “OC-SYSTEM”, and this entity runs the loops and events.

For example; if there is a loop named ‘GameRunning’, the OC-SYSTEM entity will be tagged ‘loop_GameRunning’ while the loop is active. For an event named ‘StartGame’ to run, OC-SYSTEM will be tagged ‘event_StartGame’.

The !loop command

Usage: !loop <loopName>

This command is used define a 20-ticks-per-second continous looping chain of commands. The commands following the loop command will be preceded by a conditional repeating command block that will only execute if !start_loop has been called in the previous tick.

!loop GameRunning
	>{"type":"chain", "conditional":false}
	/scoreboard players tag @a remove HasSpeed
	/scoreboard players tag @a add HasSpeed {ActiveEffects:[{Id:1b}]}
	/effect @a[tag=!HasSpeed] minecraft:speed 1 3 true

The !start_loop command

Usage: !start_loop <loopName>

This command is used to start a loop (defined using !loop) in the next tick. When started, the loop will continue until !stop_loop is called.

# TURN ON PAINT
>{"type":"impulse", "auto":false}
	!start_loop Paint
	>{"type":"chain", "auto":true}
		/say TURNED ON PAINT

The !stop_loop command

Usage: !stop_loop <loopName>

This command is used to stop a loop (defined using !loop) in the next tick.

# TURN ON PAINT
>{"type":"impulse", "auto":false}
	!stop_loop Paint
	>{"type":"chain", "auto":true}
		/say TURNED OFF PAINT

The !event command

Usage: !event <eventName>

This command is used define a run-once chain of commands. The commands following the event command will be preceded by a conditional repeating command block that will only execute if !start_event has been called in the previous tick.

# CYCLE POWERUPS
!event CyclePowerups
	>{"type":"chain", "conditional":false}
	/scoreboard players set @e[name=SYSTEM] countdown 600
	/execute @r[tag=randomPowerUp] ~ ~ ~ blockdata ~ ~ ~ {auto:1b}
	/execute @e[tag=randomPowerUp] ~ ~ ~ blockdata ~ ~ ~ {auto:0b}

The !start_event command

Usage: !start_event <eventName>

This command is used to start an event (defined using !event) in the next tick.

# TURN ON POWERUPS
>{"type":"impulse", "auto":false}
	!start_event CyclePowerups
	>{"type":"chain", "auto":true}
	!start_loop Powerups
		/say TURNED ON PAINT

Manage scoreboard objectives

The !reset_objective command

Usage: !reset_objective <objective> <criteria>

This command is used to destroy and re-create a scoreboard objective in one command. Useful for setup chains.

!reset_objective lobbyStatus dummy LOBBY STATUS

Mathematical expressions

The !math command

Usage: !math <objective>.<selector> <operator> <expression

This command can be used to create complex mathematical expressions. Normal mathematical operator precendence applies. e.g. 3 + 4 * 5 is 23 but (3 + 4) * 5 is 35.

/scoreboard objectives add money dummy
!math money.@r += 100
!math money.Notch = (money.@r * 100 + 42) / 10