Content

3D objects

A 3D shader object is something a shader draws in the world rather than a block model: a black hole, a portal, a ball of fire, a bomb that goes off. You make them in Studio (see Shaders). RP Engine puts them in the world and drives them: which state each one shows, where it is, which way it faces and how big it is. The client animates every change smoothly.

Requirements:

• A server on Minecraft 1.21.4 or newer.
• A pack built for 26.2, and players on a version that pack draws objects for.

These are different from the HUD shader objects that /rp shaders and /rp shader show on a player's screen.

Getting one on a server#

An object pushed from Studio is already known to the server as studio:<id>. Put one down and try its states:

/rp objects
/rp object spawn studio:portal
/rp object state opening

/rp objects lists every object with its size, states and sequences.

States#

States are the object's looks, defined by its code: a portal might have idle, opening and open. Entering a state starts its clock, so a one-shot (an explosion, a portal opening) plays from the start for everyone watching, and the object can blend from the state before. A state left alone for three minutes is shown as finished.

A placed object keeps its place, state, turn and size through a restart. A sequence or move that was running does not carry on.

Commands#

Everything except spawn acts on the nearest object within 64 blocks (for state and play, the nearest one that has that state or sequence). time is ticks (40) or seconds (2s), and leaving it out makes the change instant. ease is linear, in, out or in_out (the default).

Every verb works from a command block or through execute. From the console only spawn works, and it needs a size and coordinates.

Permissions#

Each verb has its own node, so you can let players run an object's sequences without letting them put new ones down. All default to op.

Sequences#

A sequence is a script of steps an object runs: drop from the sky, grow, explode, disappear. They live in the objects/ folder of a content pack, in YAML. A file can define new objects or add sequences to one that already exists, including one pushed from Studio:

# objects/portals.yml
extras:
  for: studio:portal          # adds sequences to an existing object
  sequences:
    open:
      - state: opening
      - turn: {yaw: 90, by: true, over: 2s, async: true}
      - size: {times: 2, over: 2s}
      - state: open

Run it with /rp object play open.

A full object, defined by hand:

# objects/bombs.yml
nuke:
  model: rpai:shader3d_0       # the item model that draws it
  size: 3                      # diameter in blocks when placed
  states: [idle, detonate]     # in the order the object's code numbers them
  sequences:
    drop:
      - state: idle
      - move: {by: [0, 22, 0]}                       # no "over": at once
      - wait: 10                                     # ticks; or 0.5s
      - move: {by: [0, -22, 0], over: 2.5s, ease: in}
      - sound: {name: entity.generic.explode, volume: 16, pitch: 0.5}
      - size: {to: 40, over: 2s}
      - state: detonate
      - wait: 45s
      - remove

Steps run in order:

A move, turn or resize holds the sequence until it's done, unless it has async: true. Any single timing is capped at ten minutes. Mistakes in a file are reported when the content loads, and the step or object is skipped.

From a plugin#

engine.shaderObjects() places and drives objects from Java:

ShaderObjects objects = engine.shaderObjects();
if (!objects.supported()) return;                     // 1.21.4 or newer
ContentId nuke = ContentId.parse("studio:nuke").orElseThrow();
ShaderObject bomb = objects.spawn(location, nuke).orElseThrow();
 
bomb.moveBy(new Vector(0, -20, 0), 50, Easing.IN);    // ticks
bomb.turnTo(90, 0, 0, 40, Easing.IN_OUT);             // yaw, pitch, roll
bomb.resize(40, 2, Easing.LINEAR);                    // diameter in blocks
bomb.state("detonate");
bomb.play("drop");                                    // a sequence from objects/

at(entity), near(location, radius) and loaded() find objects already placed. A handle lasts as long as its entity. Everything here runs on the main thread. See the Java API for getting the engine.