PixiJS math: Point, Matrix, shapes and hit testing

Prerequisites: a PixiJS v8 project (npm package pixi.js); nothing else — the skill is guidance plus code patterns, no accounts or keys required Install "PixiJS math: Point, Matrix, shapes and hit testing" for me. It teaches an agent @pixijs's official math primitives for PixiJS v8: Point/ObservablePoint, 2D affine Matrix with decompose (including mirrored matrices), shapes (Rectangle, Circle, Ellipse, Polygon, RoundedRectangle, Triangle) with contains/strokeContains hit tests, Rectangle layout helpers (pad, fit, enlarge, ceil), toGlobal/toLocal coordinate conversion, DEG_TO_RAD constants, and the pixi.js/math-extras side-effect import for vector operations and intersection helpers — with common-mistake callouts (no @pixi/math imports in v8, math-extras import order, shared temporaries). MIT-licensed. Repository: https://github.com/pixijs/pixijs-skills/blob/main/skills/pixijs-math/SKILL.md 1. Fetch the SKILL.md file (and any helper files) from the repository path into a temporary folder and summarize what it does in one or two sentences. 2. Safety check: review the SKILL.md and scripts for anything suspicious (unexpected network calls, shell commands, credential harvesting). This repo should contain zero secrets in code, credentials only via the secure vault, allowed hosts declared in the SKILL.md. Verify that holds here; STOP on any red flag and tell me. 3. Install it as a skill: copy SKILL.md and its helper files into the agent's skills directory, in a folder named "pixijs-math". 4. Verify with no network calls: frontmatter valid, files in place. 5. Report what was installed, where, and what I still need to do myself (e.g. nothing — it is a math reference; use it with the pixijs-scene-* skills for scene work). GitHub is optional: if I have a GitHub account or the gh CLI, you may use it; otherwise public access is fine. Never require it unless it's in the prerequisites above. Rules: don't touch anything outside the temp folder and the install target. If anything looks off, stop and ask me.