Script ECS

Script ECS

中文 · Module handbook

Define data with eve.Component, compose it with eve.Entity, and update matching entities with eve.System. Keep data in components and behavior in systems.

class Position extends eve.Component { x = 0.0; y = 0.0; }
class Actor extends eve.Entity { pos = Position; }
local actor = Actor.create();
actor.pos.x = 100;

Moving entities

Create separate Position and Velocity components, combine them in an Entity class, and derive a movement system from eve.System. Iterate matching entities() during update. Your eve_update determines system execution order explicitly.

Start with the runnable ECS example.

GPU systems

eve.ShaderSystem extends System. It packs float fields into GPU buffers and dispatches compute work during update:

local sys = eve.ShaderSystem(Moveable, gpgpu, moveGlsl)
sys.bindFields(0, "pos", ["x", "y"])
sys.bindFields(1, "vel", ["x", "y"])

Moveable and moveGlsl are your entity definition and shader source. See gpu_main.nut. For large simulations, supported range upload/readback and shared resident buffers avoid unnecessary full synchronization; consult that example and the GPU guide (Chinese).

Lifecycle

Queries return entities matching the component composition. Plan lifetime before retaining references. Prefer small components and systems over an all-purpose Actor. Do not hide side effects in component data. When hot reload replaces class definitions, migrate retained instances instead of mixing old and new layouts.

See API conventions. The ECS base classes are script-defined, so the C++ reference alone does not describe all their methods. Source.