API reference

Every public class, method, and event in @codexo/exojs. Generated from source.

classVelocityOverLifetime

@codexo/exojs-particles / particles / stable

Multiplies every live particle's velocity by a curve sampled at the particle's current `elapsed / lifetime` ratio. The same scalar is applied to both axes - the direction is preserved, only the magnitude scales. Common patterns: - **Snappy spawn, slow drift:** `[0,1]→[1,0.1]` - fast initial motion that decays over lifetime. - **Late acceleration:** `[0,0.2]→[1,1]` - particles ease in. - **Pulse:** sine-shaped curve for breathing-style motion. Note: the curve **replaces** velocity each frame relative to the previous frame's velocity, so the effect is multiplicative. Pair with `ApplyForce` if you want a constant external acceleration on top. GPU-eligible: uploads the curve as a 256-tap 1D R32F texture; sampled once per particle per frame.

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methods

events

Import

import { VelocityOverLifetime } from '@codexo/exojs-particles'

Common patterns: - **Snappy spawn, slow drift:** `[0,1]→[1,0.1]` - fast initial motion that decays over lifetime. - **Late acceleration:** `[0,0.2]→[1,1]` - particles ease in. - **Pulse:** sine-shaped curve for breathing-style motion.

Note: the curve **replaces** velocity each frame relative to the previous frame's velocity, so the effect is multiplicative. Pair with `ApplyForce` if you want a constant external acceleration on top.

GPU-eligible: uploads the curve as a 256-tap 1D R32F texture; sampled once per particle per frame.

Constructors1

new(curve: CurvePiecewise-linear keyframe curve sampled by lifetime ratio `t` in `[0, 1]`. Keyframes are stored sorted by `t` and clamped at the endpoints - sampling outside t…): VelocityOverLifetime

Methods5

apply(particles: ParticleBatchThe live particles of one system, addressed by semantic channel. This is the bulk surface an UpdateModule and a ParticleRenderMode operate on. Channels are nam…, _dt: number): void

Mutates the live particles for one frame. Runs only on the CPU path: a system whose modules are all GPU-eligible executes wgsl bodies inside its compute shader instead, and never calls this.

destroy(): void

Optional cleanup hook called from ParticleSystem.destroy.

uploadTextures(device: GPUDevice, textures: ReadonlyMap<string, GPUTexture>): void

Upload texture data (Curve/ColorGradient lookup tables) to the GPU at compile time. Receives the GPUDevice and a map of texture bindings keyed by the name in WgslContribution.textures. Called once after pipeline creation. Required when wgsl declares textures.

wgsl(): WgslContributionWhat an UpdateModule contributes to the system's composite compute shader. `body` runs once per particle in the inner main function, with these locals in scope…

Override to declare a GPU contribution. Returning a WgslContribution makes this module GPU-eligible; omitting (or returning undefined) forces CPU mode for any system that uses this module.

writeUniforms?(view: DataView, byteOffset: number, dt: number): void

Write this module's current uniform values into the shared uniform buffer at byteOffset. Layout must match the field declarations returned by wgsl (in the same order). Receives the current frame dt (seconds). Modules tracking accumulated time (e.g. noise/turbulence) should advance their internal counter here to stay in sync when running in GPU mode (where apply is not called). Required when wgsl declares uniforms. Called every frame by the system before dispatching compute.

Properties1

curve: CurvePiecewise-linear keyframe curve sampled by lifetime ratio `t` in `[0, 1]`. Keyframes are stored sorted by `t` and clamped at the endpoints - sampling outside t…

Source

packages/exojs-particles/src/modules/VelocityOverLifetime.ts