Leukocyte

Leukocyte is a simple world protection mod for Fabric providing optional integration with player-roles.

The basis of world protection with leukocyte is an "authority". An authority is responsible for applying specific rules to players within it. An authority has a unique name, as well as a priority ("level"), and set of player exclusions.

creating authorities

To create an empty authority, run: /protect add <name>.
Alternatively, an authority can be created to apply within a specific area like:

• /protect add <name> with universe (applies universally)
• /protect add <name> with <dimension> (applies within a specific dimension)
• /protect add <name> with <min> <max> (applies within a cuboid between two block coordinates)

An authority can be later removed with /protect remove <name>.

setting rules

Leukocyte provides various rules that can be applied within authorities. These rules are:

• break controls whether players can break blocks
• place controls whether players can place blocks
• block_drops controls whether blocks drop items when broken
• interact_blocks controls whether players can interact with blocks
• interact_entities controls whether players can interact with entities
• interact controls global interaction over blocks and entities
• attack controls whether players can attack other entities
• pvp controls whether players can attack other players
• spectate_entities controls whether players can spectate entities from the entity's perspective in spectator mode
• portals controls whether players can construct portals
• crafting controls whether players can craft items
• fall_damage controls whether players should receive fall damage
• hunger controls whether players will become hungry
• activate_death_protection controls whether entities should activate death protection items such as totems of undying to avoid dying
• throw_items controls whether players can throw items from their inventory
• pickup_items controls whether items can be picked up by players or other entities
• unstable_tnt controls tnt automatically igniting when placed
• ignite_tnt controls whether tnt can be ignited
• modify_flower_pots controls whether plants can be placed in or removed from flower pots
• firework_explode controls whether fireworks can explode instead of only fizzling out
• dispenser_activate controls whether dispensers and droppers can be activated
• spawn_withers controls whether withers can be summoned
• fire_tick controls whether fire tick is enabled within the authority. Defaults to gamerule if not set
• fluid_flow controls whether fluids flow
• ice_melt controls whether ice and frosted ice melt
• snow_fall controls whether snow can form on surfaces during snowfall
• coral_death controls whether coral and coral fan blocks can die
• throw_projectiles controls whether players can throw eggs, snowballs, or tridents
• shear_entities controls whether entities such as sheep and mooshrooms can be sheared by players and dispensers
• block_random_tick controls whether random ticks will apply to blocks
• fluid_random_tick controls whether random ticks will apply to fluids

To set a rule as allow or deny on an authority, use /protect set rule <authority> <rule> <result>.

For example: /protect set example place deny will disallow block placement within the authority named example.

making shapes

Often, you may want to protect an area with a weird shape that is not just a simple box. To achieve this, it is possible to combine multiple simple shapes into a more complex one which will be used to apply rules.

To start, run: /protect shape start. This will begin the construction of a shape.
Next, to add primitives to this shape, run:

• /protect shape add universe to add the universe into this shape
• /protect shape add <dimension> to add a dimension into this shape
• /protect shape add <min> <max> to add a cuboid between two block coordinates into this shape

These commands can be run multiple times to compose your shape.

Once you have finished composing a shape, you can run: /protect shape finish <name> to <authority>. This will add a shape with the given name to the given authority.

This shape can be removed in the future with /protect shape remove <name> from <authority>.

setting levels

When dealing with multiple authorities, you may want one to take priority over another. For example, you may want a global authority to disallow griefing everywhere except specific areas for building.

This is where levels come in: a level is just any number, where a higher level indicates higher priority, and a lower level indicates lower priority. Given an authority with a level of -1, an overlapping authority with a level of 10 will override the rules of the first.

Levels can be set on an authority with: /protect set level <authority> <level>.

adding exclusions

It may not be desirable for the rules of an authority to apply to everyone. In this case, it is possible to exclude specific players, or entire roles from being affected by a given authority.

This is achieved through running: /protect exclusion add <authority> player <name> or /protect exclusion add <authority> role <name>.

These exclusions can additionally be later removed with /protect exclusion remove.

putting it together: an example

That was a lot of things! Let's put this knowledge together on a simple example.

Our example server will want to have global grief protection, except in our survival dimension and free-build areas. We additionally want to be able to exclude certain players from building in the free-build areas by use of a role.

Let's consider the two dimensions: minecraft:overworld and example:survival, as well as the role builders.

First, let's create an authority named global. Since we will mostly want protection everywhere, it makes sense to globally apply protection and then specifically override this in specific areas.

• /protect add global with universe

Next, we can set the rules on this authority:

• /protect set rule global place deny
• /protect set rule global break deny

Done! Now, let's override this behavior in our survival dimension.

• /protect add survival with example:survival
• /protect set rule survival place allow
• /protect set rule survival break allow

But wait..! How will the mod know to apply the rules of global or survival, since global also applies in the survival dimension? Here, we can make use of levels: the default level for an authority is 0, and a larger value means higher priority.
So: let's set the level of our global authority to -1 such that anything we add in the future overrides it by default.

• /protect set level global -1

Now we can similarly add our free build areas as exclusions too! Let's say we have two free build areas, creatively named free_build_1 and free_build_2. First, we should create an empty authority that applies to both of them, since they both have the same rules.

• /protect add free_build
• /protect set rule free_build place allow
• /protect set rule free_build break allow

Next, let's compose the shape for free_build_1:

• /protect shape start
• /protect shape add -10 0 -10 10 255 10
  ... and add it to our authority
• /protect shape finish free_build_1 to free_build

And repeat the same for free_build_2:

• /protect shape start
• /protect shape add -100 0 -10 90 255 10
  ... and add it to our authority
• /protect shape finish free_build_2 to free_build

Done! Now the free-build areas should be editable by any player- except, we want to create exclusions such that we can 'ban' players from the areas. Let's do that with a free_build_banned role:

• /protect exclusion add free_build role free_build_banned

With that, all our protection should be set up nicely! :)

testing! querying and checking rules

Okay, we've set up authorities, but how can we easily check which rules are set and by what?

A few commands may come in handy:

• /protect test: tests all the rules that apply at a given location, and shows from which authority they originate
• /protect list: lists all authorities in the world
• /protect display <authority>: displays the rules and shape of the given authority