pixijs-color — Claude Code skill: what it does, how to install
PixiJS v8 skill for the Color class. It guides color conversions, tint calculations, and buffer reuse to prevent GC spikes in animation loops.
npx skills add pixijs/pixijs-skills --skill pixijs-color -a claude-codeWhat pixijs-color does
The skill instructs the coding agent on working with the Color class in PixiJS v8. Most scene APIs accept raw hex numbers and CSS strings directly as ColorSource. Instantiating new Color(...) is only required when converting between representations or altering values. It details valid inputs, including CSS strings, 8-digit hex codes, HSL objects, and typed arrays like Uint8ClampedArray.
It explains conversion methods like toHex(), toNumber(), toRgba(), and GPU vertex packing via toBgrNumber(). For render loops, it enforces memory efficiency. Instead of instantiating objects per frame inside app.ticker, it directs the agent to reuse buffers with toArray(out) or use the Color.shared singleton.
Methods multiply() and premultiply() mutate the instance in place and set value to null. That causes the original format to be lost. For non-destructive tint math, the instructions point to toPremultiplied() instead.
What it helps with
- convert CSS color strings and hex values into PixiJS formats
- eliminate GC overhead in render loops using
Color.shared - pack colors into 24-bit integers for GPU vertex buffers
- calculate premultiplied alpha without mutating the source color
Example prompts for the agent
- Show how to update sprite.tint in app.ticker using Color.shared to avoid allocations
- Convert a normalized 0-1 RGBA array into a hex string for PixiJS v8
- How do I pack a color for GPU vertex attributes using toBgrNumber()?
How to install pixijs-color
1Skills CLI (Vercel)
npx skills add pixijs/pixijs-skills --skill pixijs-color -a claude-code2Manually: put the files in place
~/.claude/skills/pixijs-color/SKILL.mdCopy the whole skill folder; for one project use .claude/skills/pixijs-color/
1Skills CLI (Vercel)
npx skills add pixijs/pixijs-skills --skill pixijs-color -a codex2Manually: put the files in place
.agents/skills/pixijs-color/SKILL.mdFor all projects use ~/.agents/skills/
1Skills CLI (Vercel)
npx skills add pixijs/pixijs-skills --skill pixijs-color -a cursor2Manually: put the files in place
.cursor/skills/pixijs-color/SKILL.mdCursor also reads .agents/skills/ and .claude/skills/
1GitHub CLI
gh skill install pixijs/pixijs-skills pixijs-color2Manually: put the files in place
.github/skills/pixijs-color/SKILL.md1Skills CLI (Vercel)
npx skills add pixijs/pixijs-skills --skill pixijs-color -a gemini-cli2Platform CLI
gemini skills install https://github.com/pixijs/pixijs-skills --path skills/pixijs-colorManually: put the files in place
.devin/skills/pixijs-color/SKILL.mdThe legacy .windsurf/skills/ path still works
Skills CLI (Vercel)
npx skills add pixijs/pixijs-skills --skill pixijs-color -a opencodeClaude.ai
Zip the folder and upload it in Settings → Capabilities → Skills
Step by step, with commands for each platform: How to install skills in Claude Code: five ways
Questions about pixijs-color
How to install pixijs-color in Claude Code?
Run npx skills add pixijs/pixijs-skills --skill pixijs-color -a claude-code in your terminal. It adds the skill configuration to your Claude setup.
When is new Color() required in PixiJS v8?
Most APIs accept plain strings and hex integers directly through ColorSource. Explicit instantiation is only needed to convert formats or manipulate values like alpha and tint.
Why use Color.shared instead of new instances?
It is a singleton designed for hot paths like app.ticker. It eliminates object allocations and garbage collection overhead during per-frame tint adjustments.
Source text
SKILL.md · MIT
---
name: pixijs-color
description: "Use this skill when creating, converting, or manipulating colors in PixiJS v8. Covers Color class input formats (hex, CSS names, RGB/HSL objects, arrays, Uint8Array), conversion methods (toHex, toNumber, toArray, toRgba), component access, setAlpha/multiply/premultiply, Color.shared singleton. Triggers on: Color, ColorSource, hex, rgb, hsl, tint, premultiply, Color.shared, color conversion."
license: MIT
---
The `Color` class creates and converts colors for tints, fills, strokes, and anywhere PixiJS accepts a `ColorSource`. Most APIs accept raw hex/strings directly, so explicit `new Color(...)` is only needed when converting formats or manipulating values.
## Quick Start
```ts
const fillColor = new Color("#ff6600");
console.log(fillColor.toHex()); // '#ff6600'
console.log(fillColor.toNumber()); // 0xff6600
console.log(fillColor.toArray()); // [1, 0.4, 0, 1]
const g = new Graphics().rect(0, 0, 200, 100).fill(fillColor);
app.stage.addChild(g);
const sprite = Sprite.from("hero.png");
sprite.tint = "dodgerblue";
app.stage.addChild(sprite);
const t = Color.shared.setValue(0xffffff).multiply([1, 0.5, 0.5]).toNumber();
sprite.tint = t;
```
**Related skills:** `pixijs-scene-graphics` (fill/stroke colors), `pixijs-scene-sprite` (tint), `pixijs-blend-modes` (compositing).
## Core Patterns
### Accepted input formats
```ts
import { Color } from "pixi.js";
// Hex integer
new Color(0xff0000);
// Hex strings
new Color("#ff0000");
new Color("#f00");
new Color("ff0000");
// CSS color names
new Color("red");
new Color("dodgerblue");
// RGB/RGBA objects (components 0-255)
new Color({ r: 255, g: 0, b: 0 });
new Color({ r: 255, g: 0, b: 0, a: 0.5 });
// HSL/HSLA objects
new Color({ h: 0, s: 100, l: 50 });
new Color({ h: 0, s: 100, l: 50, a: 0.5 });
// HSV/HSVA objects
new Color({ h: 0, s: 100, v: 100 });
// CSS strings
new Color("rgb(255, 0, 0)");
new Color("rgba(255, 0, 0, 0.5)");
new Color("hsl(0, 100%, 50%)");
// Normalized 0-1 arrays (Float32Array or plain arrays)
new Color([1, 0, 0]); // RGB
new Color([1, 0, 0, 0.5]); // RGBA
// Uint8 arrays (components 0-255)
new Color(new Uint8Array([255, 0, 0]));
new Color(new Uint8ClampedArray([255, 0, 0, 128]));
// 8-digit hex with alpha
new Color("#ff0000ff");
new Color("#f00f");
// Copy from another Color instance
const red = new Color("red");
const copy = new Color(red);
```
### Conversion methods
```ts
import { Color } from "pixi.js";
const color = new Color("#ff6600");
color.toHex(); // '#ff6600'
color.toHexa(); // '#ff6600ff' (hex with alpha)
color.toNumber(); // 0xff6600
color.toArray(); // [1, 0.4, 0, 1] (normalized RGBA)
color.toRgbArray(); // [1, 0.4, 0] (normalized RGB, no alpha)
color.toRgbaString(); // 'rgba(255,102,0,1)'
color.toRgba(); // { r: 1, g: 0.4, b: 0, a: 1 }
color.toRgb(); // { r: 1, g: 0.4, b: 0 }
color.toUint8RgbArray(); // [255, 102, 0]
// setValue() is the chainable way to change a color's value
color.setValue(0xff0000).toHex(); // '#ff0000'
```
### Component access
```ts
import { Color } from "pixi.js";
const color = new Color("rgba(255, 128, 0, 0.8)");
color.red; // 1
color.green; // ~0.502
color.blue; // 0
color.alpha; // 0.8
```
All component getters return normalized 0-1 values.
### Manipulation
```ts
import { Color } from "pixi.js";
const color = new Color("red");
// Set alpha (chainable)
color.setAlpha(0.5);
// Multiply with another color (destructive, modifies in place)
color.multiply(0x808080);
// Premultiply alpha (destructive, RGB channels multiplied by alpha)
color.premultiply(0.8);
// Premultiply alpha only (RGB unchanged)
color.premultiply(0.8, false);
// Chain operations
new Color("white").setAlpha(0.5).multiply([0.8, 0.2, 0.2]);
```
`multiply()` and `premultiply()` are destructive; they modify the color and set `value` to null (original format is lost).
### Non-destructive premultiplied output
```ts
import { Color } from "pixi.js";
const color = new Color("red").setAlpha(0.5);
const packed = color.toPremultiplied(color.alpha); // 0x7F7F0000
const alphaOnly = color.toPremultiplied(color.alpha, false); // 0x7FFF0000
```
`toPremultiplied(alpha, applyToRGB?)` returns a 32-bit `0xAARRGGBB` integer without mutating `this`. Use it in batchers and tint math where the source color must be reused. When `applyToRGB` is `false`, only the alpha byte is packed; the RGB stays at its full value.
### Reusing output buffers
```ts
import { Color } from "pixi.js";
const rgba = new Float32Array(4);
const rgb = new Float32Array(3);
const rgb8 = new Uint8Array(3);
app.ticker.add(() => {
Color.shared.setValue(sprite.tint).toArray(rgba).toRgbArray(rgb);
Color.shared.toUint8RgbArray(rgb8);
});
```
`toArray(out?)`, `toRgbArray(out?)`, and `toUint8RgbArray(out?)` accept a reusable `number[]`, `Float32Array`, `Uint8Array`, or `Uint8ClampedArray` and write into it. Pass your own buffer in hot paths to avoid allocating per frame; omit the argument and the `Color` instance returns its internal cache array.
### Packing for GPU buffers
| Method | Returns |
| ------------------------ | ------------------------------------------------------------ |
| `toBgrNumber()` | 24-bit `0xBBGGRR` integer with R/B swapped |
| `toLittleEndianNumber()` | Same 24-bit swap, convenient for little-endian vertex writes |
Both are cheap and useful when emitting colors straight into packed vertex attributes.
### Color.shared for temporary operations
```ts
import { Color } from "pixi.js";
// One-off conversion without allocating a new Color
const hex = Color.shared.setValue("#ff6600").toNumber();
const arr = Color.shared.setValue(0xff0000).toArray();
```
`Color.shared` is a singleton that avoids allocating a new `Color` on every call. This matters in hot paths like render loops or per-frame tint calculations where repeated `new Color()` creates GC pressure. Do not store references to it; other code may mutate it.
```ts
import { Color } from "pixi.js";
// Good: reuse shared instance in a per-frame callback
app.ticker.add(() => {
const t = performance.now() / 1000;
sprite.tint = Color.shared
.setValue("white")
.multiply([Math.sin(t) * 0.5 + 0.5, 0.2, 0.8])
.toNumber();
});
```
### Validating input
```ts
import { Color } from "pixi.js";
Color.isColorLike("red"); // true
Color.isColorLike("#ff0000"); // true
Color.isColorLike(0xff0000); // true
Color.isColorLike([1, 0, 0]); // true
Color.isColorLike({ r: 1, g: 0, b: 0 }); // true
Color.isColorLike({ foo: 1 }); // false
Color.isColorLike(null); // false
```
`Color.isColorLike()` checks the structural shape (string, number, array, or recognized object). It doesn't validate that a string is a real CSS color name, nor that array values fall in range. Use it as a type guard before passing user input to `new Color()` or `setValue()`.
## Common Mistakes
### [MEDIUM] Expecting toRgba() to return 0-255 values
Wrong:
```ts
import { Color } from "pixi.js";
const { r, g, b } = new Color({ r: 255, g: 128, b: 0 }).toRgba();
// r = 1, g = ~0.502, b = 0 (NOT 255, 128, 0)
```
Correct:
```ts
import { Color } from "pixi.js";
// Use toUint8RgbArray() for 0-255 output
const [r, g, b] = new Color({ r: 255, g: 128, b: 0 }).toUint8RgbArray();
// r = 255, g = 128, b = 0
```
RGB object _inputs_ use 0-255 range (`{ r: 255, g: 0, b: 0 }`), but all output methods (`toRgba()`, `toRgb()`, `toArray()`, `toRgbArray()`) normalize to 0-1. Use `toUint8RgbArray()` when you need 0-255 integers for CSS or external APIs.
### [MEDIUM] Using 0-255 range in color arrays
Wrong:
```ts
import { Color } from "pixi.js";
new Color([255, 0, 0]); // NOT red; values are interpreted as 0-1
```
Correct:
```ts
import { Color } from "pixi.js";
new Color([1, 0, 0]); // red via normalized array
new Color(0xff0000); // red via hex
new Color("red"); // red via CSS name
new Color(new Uint8Array([255, 0, 0])); // red via Uint8Array (0-255)
```
Plain number arrays (`number[]` and `Float32Array`) use normalized 0-1 range. `[255, 0, 0]` clamps to `[1, 0, 0]` because values are clamped, but `[200, 100, 50]` does not produce the expected color. Use `Uint8Array` or `Uint8ClampedArray` for 0-255 input.
### [MEDIUM] Using utils.string2hex or utils.hex2string
Wrong:
```ts
import { utils } from "pixi.js";
const hex = utils.string2hex("#ff0000");
```
Correct:
```ts
import { Color } from "pixi.js";
const hex = new Color("#ff0000").toNumber();
const str = new Color(0xff0000).toHex();
```
The `utils` namespace was removed in v8. Use the `Color` class for all color conversions.
## API Reference
- [Color](https://pixijs.download/release/docs/color.Color.html.md)
- [ColorSource](https://pixijs.download/release/docs/color.ColorSource.html.md)
© pixijs · MIT · pixijs/pixijs-skills