raisaksham377-bot/youtube-shorts-ai-editor

VidTSX 2D Video Generator

Generate production-ready 2D TSX video files for VidTSX from a description of a shot or video. The files are Remotion compositions that VidTSX renders frame-by-frame, so correctness matters more than cleverness: a single non-monotonic interpolate range or a stray useState will crash the render.

This skill covers 2D motion graphics. 3D work (@remotion/three / React Three Fiber) is out of scope.

How to use this skill

1. Clear single shot → generate the .tsx file directly.
2. Complex, multi-shot, or visually ambiguous request → confirm the shot breakdown or visual direction in one short message first, then generate. Don't over-ask; a one-line confirmation is enough.
3. Deliver as an actual .tsx file, not inline code. These TSX components always exceed 20 lines, and the user edits these files directly. Default to one shot per file (atomic, easy to edit) unless the user asks for a single combined deliverable.
4. The file contains only the component code — the structural section comments below are welcome, but no markdown fences, no prose explanations inside the file.
5. Render it and look before calling it done — see Verify the render. A shot you have only reasoned about is not finished; a still (and, for reveals/scrolls, frames at each cue) is the bar.

---

Output spec

Dimension presets

Format	Width	Height	Use case
horizontal	1920	1080	YouTube, presentations
vertical	1080	1920	TikTok, Reels, Shorts
square	1080	1080	Instagram feed

Defaults

• Format: horizontal (1920×1080)
• Duration: 5 seconds
• FPS: 30
• Style: minimalist (see references/style-presets.md)

---

Mandatory file structure

Every generated file follows this skeleton. The labeled section comments are intentional — they keep large files navigable.

import React from 'react';
import {
  useCurrentFrame,
  useVideoConfig,
  interpolate,
  Easing,
  AbsoluteFill,
  Sequence,
} from 'remotion';

// =============================================================================
// COMPOSITION CONFIG
// =============================================================================
export const compositionConfig = {
  id: 'ComponentName', // PascalCase only — NO hyphens or underscores
  durationInSeconds: 5,
  fps: 30,
  width: 1920,
  height: 1080,
};

// =============================================================================
// STYLE CONSTANTS
// =============================================================================
const COLORS = {
  primary: '#6366f1',
  secondary: '#8b5cf6',
  accent: '#06b6d4',
  background: '#0f0f23',
  text: '#ffffff',
} as const;

const TYPOGRAPHY = {
  fontFamily: 'Inter, system-ui, sans-serif',
} as const;

const EASINGS = {
  easeOut: Easing.bezier(0.33, 1, 0.68, 1),
  easeIn: Easing.bezier(0.32, 0, 0.67, 0),
  easeInOut: Easing.bezier(0.37, 0, 0.63, 1),
  overshoot: Easing.bezier(0.34, 1.56, 0.64, 1),
} as const;

// =============================================================================
// PRE-GENERATED DATA (computed once at module level, NOT during render)
// =============================================================================
const seededRandom = (seed: number): number => {
  const x = Math.sin(seed * 9999) * 10000;
  return x - Math.floor(x);
};

// =============================================================================
// MAIN COMPONENT
// =============================================================================
const ComponentName: React.FC = () => {
  const frame = useCurrentFrame();
  const { fps, durationInFrames, width, height } = useVideoConfig();

  return (
    <AbsoluteFill style={{ backgroundColor: COLORS.background }}>
      {/* Content */}
    </AbsoluteFill>
  );
};

export default ComponentName;

Swap ComponentName for a PascalCase name describing the shot, set the COLORS block from the chosen style preset, and set width/height/durationInSeconds/fps from the request.

---

Correctness rules

These are not stylistic preferences — they are what makes a render succeed. VidTSX (via Remotion) renders each frame by calling the component at a fixed frame number. There is no event loop, no persistence between frames, and no wall-clock time. Anything that assumes those things will break.

Animation is frame-based, always

• Drive all motion from useCurrentFrame() + interpolate().
• Never use useState, useEffect, setTimeout, setInterval, or CSS animations/transitions. They don't fit the frame-by-frame model and produce broken or non-deterministic output.
• For anything random or procedural, use seededRandom (or an equivalent seeded function) so every render of a given frame is identical. Pre-generate particle/random arrays at module level, never inside the render function — recomputing per frame causes flicker.
• Stagger animations so elements enter in sequence rather than all at once. It reads better and is the expected look.

interpolate — input ranges must be strictly increasing

interpolate's input range has to be strictly monotonically increasing. Duplicate or descending values throw at runtime.

// ✅ Correct
interpolate(frame, [0, 30, 60], [0, 1, 0]);

// ❌ Throws — input range descends
interpolate(frame, [60, 30, 0], [0, 1, 0]);

To reverse a mapping, flip the output range, never the input range:

// ✅ Correct — maps 0→100, 1→0
interpolate(value, [0, 1], [100, 0]);

// ❌ Wrong
interpolate(value, [1, 0], [100, 0]);

For index-based timing, make sure startFrame < endFrame and always clamp:

const startFrame = index * 30;
const endFrame = startFrame + 30;
interpolate(frame, [startFrame, endFrame], [0, 1], {
  extrapolateLeft: 'clamp',
  extrapolateRight: 'clamp',
});

Always pass extrapolateLeft: 'clamp' and extrapolateRight: 'clamp' unless an unbounded value is genuinely wanted — without them, values shoot past their range before/after the keyframes.

Easing — use Easing.bezier(), never wrapper syntax

Wrapper forms like Easing.out(Easing.cubic) crash. Define named beziers once (see the EASINGS block in the skeleton) and reference them:

// ❌ Crashes
Easing.out(Easing.cubic);
Easing.in(Easing.quad);

// ✅ Correct
interpolate(frame, [0, 30], [0, 1], {
  easing: EASINGS.easeOut,
  extrapolateRight: 'clamp',
});

chroma-js — namespace import only

// ✅ Correct
import * as chroma from 'chroma-js';
const color = chroma('#00bfff').brighten(0.5).hex();

// ❌ Wrong — "chroma is not a function"
import chroma from 'chroma-js';

@remotion/paths — only the real functions exist

These helpers do not exist and must never be used: makeCircle(), makeRect(), makeTriangle(), makeLine(), makePie(), makePolygon(), makeEllipse(), makeStar().

Only these imports are valid:

import { evolvePath, getLength, getPointAtLength, getTangentAtLength } from '@remotion/paths';

Write SVG path strings by hand and animate them with evolvePath:

const circlePath = 'M 50 10 A 40 40 0 1 1 49.99 10 Z';
const rectPath = 'M 0 0 L 100 0 L 100 50 L 0 50 Z';
const linePath = 'M 0 0 L 100 100';

const { strokeDasharray, strokeDashoffset } = evolvePath(progress, rectPath);

Composition ID

compositionConfig.id is PascalCase only — no hyphens, no underscores (e.g. ProductReveal, not product-reveal or product_reveal).

---

Layout

Safe zones

• Top 10%: reserve for platform UI.
• Bottom 15%: reserve for captions/buttons.
• Keep primary content between 25%–75% vertically.

Centering helper

const centered: React.CSSProperties = {
  position: 'absolute',
  top: '50%',
  left: '50%',
  transform: 'translate(-50%, -50%)',
};

---

Typography

Element	Size	Weight
Headlines	72–120px	700–900
Subheadlines	36–48px	500–700
Body	28–36px	400–500

Always set margin: 0 on text elements — browser defaults push layouts off-center.

---

Style presets

When the user names a style, load its palette and characteristics from references/style-presets.md and drop the COLORS object into the skeleton. The six presets are: minimalist (default), memphis, neo-brutalism, glassmorphism, neon/cyberpunk, and corporate. If no style is named, use minimalist.

---

Verify the render (do not skip)

A shot is not done until you have looked at it. After writing the .tsx, render at least one still and open it — never hand over a shot you have only reasoned about. Rendering succeeds and the numbers look right, yet text overflows its card, an image is cropped at the wrong crop, an element is off-screen, or two things overlap. Only a screenshot catches these.

• Render a still (e.g. node scripts/render-all.mjs --still --scale=1 <ShotId>) and Read the PNG.
• For time-based reveals (elements entering on a cue, scrolls, staged phases), a single 60%-of-duration still is not enough — render the full clip and pull frames at each key moment (ffmpeg -ss <t> -i out/<id>.mp4 -frames:v 1 f.jpg), or render stills at several offsets. Verify the state at each cue, not just one frame.
• Check specifically: images fit their slot (no important content cropped; prefer objectFit: contain on a matching background for heterogeneous real images), text is not clipped or overflowing, nothing is off the safe area, and each animated element is actually visible when it should be.
• If it is composited over other footage, also spot-check a frame from the final baked output, not just the isolated shot.

Fix what the screenshot reveals, then re-render and look again. Treat "I rendered it and it looks correct" — with the frame shown — as the bar for done.

---

Final output

Generate the complete .tsx file and nothing else inside it — no surrounding markdown, no commentary before or after the code in the file itself. A short one-line note in chat when handing over the file is fine.