How do I install the Vectojs Video Exporter skill?

Run npx skillmds@latest add vectojs/vectojs-video-exporter in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Vectojs Video Exporter safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Vectojs Video Exporter?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Vectojs Video Exporter free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Vectojs Video Exporter?

vectojs (@vectojs) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Vectojs Video Exporter by vectojs — Agent Skill

Name: Vectojs Video Exporter
Author: vectojs

File contents

VectoJS Video Exporter

Use this skill to export VectoJS canvas scenes to deterministic MP4 files through Chromium and FFmpeg.

Export workflow

Confirm ffmpeg with libx264 is on PATH.
Confirm Chromium resolution: PUPPETEER_EXECUTABLE_PATH, system Chromium, or Puppeteer’s browser.
Ensure the rendered page exposes window.vectoScene with callable stop() and step(dt).
Keep animations deterministic: use Scene.step(dt), seeded randomness, and no wall-clock/network dependence.
Choose local module or hosted URL input.
Use cancellation with AbortController for API calls or signals for CLI jobs.
Verify the output frame count and existing-file preservation on failure when release quality matters.

Read references/export-recipes.md for CLI/API snippets.

Current 0.2 contract

CLI binary: vecto-export.
API: exportVideo(options).
First page <canvas> is resized and captured.
Output is H.264 MP4 with yuv420p.
Frame count is Math.ceil(fps * duration).
Failed or aborted exports preserve an existing destination and remove incomplete staged files.
SIGINT/SIGTERM clean up Chromium, Vite, FFmpeg, progress output, and staged files.
Capture runs at deviceScaleFactor: 1 — output resolution equals width×height exactly, independent of the host machine's DPR.
The exporter calls scene.stop() itself, then drives step(dt) per frame; the page only needs to expose the scene, not manage the loop. step() uses the Scene's main renderer, so particle simulations advance deterministically.

Sandbox policy

Keep Chromium sandboxing enabled for normal users. It is disabled only when running as root or when VECTO_CHROMIUM_NO_SANDBOX=1 is explicitly set. Prefer a non-root export process.

Common mistakes

Mistake	Correction
Forgetting `window.vectoScene`	Expose the Scene after adding entities and before starting export.
Using wall-clock animation	Drive state from `step(dt)` time or seeded simulation state.
Publishing helper HTML into source dirs	Use local module input; exporter serves it through in-memory Vite HTML.
Killing the process without cleanup	Use AbortController or process signals and wait for cleanup.
Assuming browser export works on CI	Install FFmpeg and Chromium; set `PUPPETEER_EXECUTABLE_PATH` when needed.

---name: vectojs-video-exporterdescription: Use when exporting VectoJS scenes to H.264 MP4 with @vectojs/video-exporter, CLI/API capture, fixed-step scene contracts, Chromium, FFmpeg, cancellation, cleanup, or deterministic animation rendering.---# VectoJS Video ExporterUse this skill to export VectoJS canvas scenes to deterministic MP4 files through Chromium and FFmpeg.## Export workflow1. Confirm `ffmpeg` with `libx264` is on `PATH`.2. Confirm Chromium resolution: `PUPPETEER_EXECUTABLE_PATH`, system Chromium, or Puppeteer’s browser.3. Ensure the rendered page exposes `window.vectoScene` with callable `stop()` and `step(dt)`.4. Keep animations deterministic: use `Scene.step(dt)`, seeded randomness, and no wall-clock/network dependence.5. Choose local module or hosted URL input.6. Use cancellation with `AbortController` for API calls or signals for CLI jobs.7. Verify the output frame count and existing-file preservation on failure when release quality matters.Read `references/export-recipes.md` for CLI/API snippets.## Current 0.2 contract- CLI binary: `vecto-export`.- API: `exportVideo(options)`.- First page `<canvas>` is resized and captured.- Output is H.264 MP4 with `yuv420p`.- Frame count is `Math.ceil(fps * duration)`.- Failed or aborted exports preserve an existing destination and remove incomplete staged files.- SIGINT/SIGTERM clean up Chromium, Vite, FFmpeg, progress output, and staged files.- Capture runs at `deviceScaleFactor: 1` — output resolution equals `width`×`height` exactly, independent of the host machine's DPR.- The exporter calls `scene.stop()` itself, then drives `step(dt)` per frame; the page only needs to expose the scene, not manage the loop. `step()` uses the Scene's main renderer, so particle simulations advance deterministically.## Sandbox policyKeep Chromium sandboxing enabled for normal users. It is disabled only when running as root or when `VECTO_CHROMIUM_NO_SANDBOX=1` is explicitly set. Prefer a non-root export process.## Common mistakes| Mistake | Correction || --------------------------------------- | ------------------------------------------------------------------------- || Forgetting `window.vectoScene` | Expose the Scene after adding entities and before starting export. || Using wall-clock animation | Drive state from `step(dt)` time or seeded simulation state. || Publishing helper HTML into source dirs | Use local module input; exporter serves it through in-memory Vite HTML. || Killing the process without cleanup | Use AbortController or process signals and wait for cleanup. || Assuming browser export works on CI | Install FFmpeg and Chromium; set `PUPPETEER_EXECUTABLE_PATH` when needed. |

Frequently asked questions

Vectojs Video Exporter