Entity Movement

Entity movement is a confusing subject, with many pieces that must be done correctly, or your entity will not move. The following is required:

Movement Speed

The first thing your entity needs is a speed component. This sets how quickly your entity will move through the world.

ComponentNote
minecraft:movementSet movement speed on land.
minecraft:underwater_movementSet movement speed in the water.
minecraft:flying_speedSet the speed in the air.

You should always include minecraft:movement. Add the other two as needed.

All vanilla swimming" entities like Dolphin include underwater_movement. Only some flying entities have flying_speed. It is not known why this is the case.

Movement Type

Your entity will also need a movement type. Movement types set hard-coded behavior for how your entity will move through the world.

You may only include one movement type in your entity. Select the component that most closely matches your needs.

ComponentNote
minecraft:movement.amphibiousThis move control allows the mob to swim in the water and walk on land.
minecraft:movement.basicThis component accents the movement of an entity.
minecraft:movement.flyThis move control causes the mob to fly.
minecraft:movement.genericThis move control allows a mob to fly, swim, climb, etc.
minecraft:movement.hoverThis move control causes the mob to hover.
minecraft:movement.jumpMove control causes the mob to jump as it moves with a specified delay between jumps.
minecraft:movement.skipThis move control causes the mob to hop as it moves.
minecraft:movement.swayThis move control causes the mob to sway side to side, giving the impression it is swimming.

Movement Modifiers

Movement modifiers provide additional information about how your entity will move through the world.

ComponentNote
minecraft:water_movementSets the friction the entity experiences in water.
minecraft:rail_movementSets that the entity can move on rails (only).
minecraft:friction_modifierSets the friction the entity experiences on land.

The next thing your entity needs is a navigation component. Navigation components have quite a few fields, like whether the entity can open doors or avoid sunlight. How you set these fields is generally more important than the navigation component you pick.

The reason there are so many navigation components is that each one gives a slightly different hard-coded behavior. Pick the navigation component whose name/description best matches the kind of navigation your entity will be doing.

You can only have one navigation component at any given time.

ComponentNote
minecraft:navigation.climbAllows this entity to generate paths that include vertical walls like the vanilla Spiders do.
minecraft:navigation.floatAllows this entity to generate paths by flying around the air like the regular Ghast.
minecraft:navigation.genericAllows this entity to generate paths by walking, swimming, flying and climbing around, and jumping up and down a block.
minecraft:navigation.flyAllows this entity to generate paths in the air as the vanilla Parrots do.
minecraft:navigation.swimAllows this entity to generate paths that include water.
minecraft:navigation.walkAllows this entity to generate paths by walking around and jumping up and down a block like regular mobs.

On top of the movement and the navigation component, there exist many additional components to augment the abilities of your entity as they move through the world.

ComponentNote
minecraft:annotation.break_doorAllows entity to break doors. It must also be turned on in the navigation component.
minecraft:annotation.open_doorAllows entity to open doors. It must also be turned on in the navigation component.
minecraft:buoyantSpecify which liquids the entity can float in.
minecraft:can_climbAllows this entity to climb up ladders.
minecraft:can_flyMarks the entity as being able to fly. The pathfinder won't be restricted to paths where a solid block is required underneath it.
minecraft:can_power_jumpAllows the entity to power jump like the horse does in vanilla.
minecraft:floats_in_liquidSets that this entity can float in liquid blocks.

There are also components like minecraft:preferred_path, which will modify navigation based on block-based path-cost.

AI

The navigation component tells the entity how to generate paths, but it doesn't say when or where to generate directions. This is what the AI components are for.

AI components are prefixed with behavior.

There are too many AI components that generate paths to list in this document. A few will be provided as examples:

Component
minecraft:behavior.random_stroll
minecraft:behavior.run_around_like_crazy

Contributors

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