Jecs Spring

Utility for running springs in Jecs.

Setup

• Call jecs_spring.world(world) before using it to set it up with your world.

• Add jecs_spring.system(delta) to your systems. Set the order right before your component values apply. This system needs the delta time to step the springs.

local c = require(components)
local jecs_spring = require(jecs_spring)

jecs_spring.world(world)

return {
    system = function(delta: number)
        jecs_spring.system(delta)
    end
}

Usage

• Use jecs_spring.goal as a pair to set your goal value.

• The target should be the component you want to interpolate

• The value of the pair should be the goal value. This value should be any of ripple Animatable types (number | vector | Vector3 | Vector2 | CFrame | Color3 | UDim | UDim2 | Rect).

local spring = require(jecs_spring)

local cube = world:entity()

world:set(cube, c.size, Vector3.new(1, 1, 1))
world:set(cube, pair(spring.goal, c.size), Vector3.new(2, 2, 2))

-- cube will go from 1 -> 2

Configuring the spring.

• Use jecs_spring.options as a pair to set the options for the spring. Similar to jecs.goal, the target is the component's spring you want to configure.

• Its recommended that you set the options before the goal so the spring starts with the correct configuration.

local spring = require(jecs_spring)

local cube = world:entity()

world:set(cube, c.size, Vector3.new(1, 1, 1))
world:set(cube, pair(spring.options, c.size), { friction = 30, tension = 800 })
world:set(cube, pair(spring.goal, c.size), Vector3.new(2, 2, 2))

-- cube will go from 1 -> 2 with a friction of 30 and tension of 800

Manipulating the spring object.

• The spring object is stored in a jecs_spring.motion pair. The target is the component's spring.

• The spring object is available right after you set the goal.

• The spring object is destroyed when the goal is removed.

local spring = require(jecs_spring)

local cube = world:entity()

world:set(cube, c.size, Vector3.new(1, 1, 1))
world:set(cube, pair(spring.goal, c.size), Vector3.new(2, 2, 2))

local spring_motion = world:get(cube, pair(spring.motion, c.size))
spring_motion:impulse(Vector3.new(5, 5, 5))

Checking spring completion.

• Springs that have completed will be marked with a jecs_spring.completed pair. The target is the component's spring.

• The completed pair is removed if you change the goal.

• The completed pair is removed if you remove the goal.

local spring = require(jecs_spring)

local cube = world:entity()
world:set(cube, c.size, Vector3.new(3, 3, 3))

task.wait(2)
-- animate out
world:set(cube, pair(spring.goal, c.size), Vector3.zero)

function system()
    for entity in world:query(pair(spring.completed, c.size)) do
        world:delete(entity)
    end
end