gpui-shaders

name	gpui-shaders
description	Metal/wgpu/WGSL shader surfaces for native Rust gpui apps (Zed-family, pd-console), stockpiled with beautiful copy-pasteable shader-toy examples. Use for custom GPU fragment passes behind/around gpui panes: ocean/water shaders, pixelated waves and boats, a living harbor, dithered chrome borders, sonar sweeps, aurora/starfields, CRT/scanline post. Trigger on: wgsl, wgpu, metal shader, gpui shader, shadertoy, fragment shader, SDF, noise/fbm, ordered dithering, pixelation, render-to-texture, "pixelated waves and boats", living harbor water. NOT for: web/GLSL/three.js shaders (use a web tool), non-shader gpui motion (use rust-gpui-motion), general GUI layout/color (use beautiful-gui-design), CLI/TUI (use beautiful-cli-design).
license	Apache-2.0
allowed-tools	Read,Write,Edit,Bash,Grep,Glob
metadata	{"provenance":{"kind":"first-party","owners":["port-daddy"]},"pairs-with":[{"skill":"rust-gpui-motion","reason":"Animates/fades the shader surface into the pane tree once the fragment pass exists (opacity, timing)."},{"skill":"vello-parley-rendering","reason":"The vector-drawing neighbor — use Vello instead of WGSL when the effect is shapes/text, not per-pixel work."},{"skill":"metal-text-pipeline","reason":"The bare-metal text-rendering neighbor sharing the same Metal/wgpu surface plumbing on macOS."},{"skill":"build-coop-ide-gpui","reason":"The gpui IDE host this skill's shader surfaces (companion window, render-to-texture) get embedded into."}],"io-contract":{"kind":"deliverable","consumes":["[Truncated]","[Truncated]"],"produces":["[Truncated]","[Truncated]"]}}

gpui Shaders

Run your own WGSL fragment shaders on Metal (via wgpu) and get their pixels onto a native gpui window — for the per-pixel effects the element tree can't do (water, noise fields, dither, glints). The aesthetic house style is pixelated + dithered retro-futurism on the maritime palette; the engineering rule is earn the GPU pass — most "shader" ideas are better done with a gpui primitive or a Vello vector pass.

When to Use

• A surface needs genuine per-pixel work: ocean/water, noise/fbm fields, raymarching, full-res dither, glints, a living-harbor backdrop.
• You want a shader-toy effect (SDF shapes, palettes, domain-warped noise) inside or behind a gpui pane.
• Building the "living harbor" viz, dithered chrome borders, a sonar/radar sweep, signal-flag shimmer, or a CRT/scanline post pass.

NOT for

• Web shaders (GLSL/three.js/WebGL/<canvas>) — different runtime entirely.
• Non-shader motion/transitions in gpui — use rust-gpui-motion.
• Plain vector/2D drawing that Vello or gpui paint/canvas already does — don't reach for a raw fragment pass.
• General layout, color systems, typography — beautiful-gui-design. CLI/TUI — beautiful-cli-design.

Decision Points

flowchart TD
  A[Want a visual effect on a gpui surface] --> B{Does it need TRUE per-pixel work?\n(noise, SDF field, water, raymarch, full-res dither)}
  B -->|No, it's shapes/quads/text| C[gpui element tree or paint/canvas]
  B -->|No, but vector + crisp text| D[Vello vector pass]
  B -->|Yes| E{Must it sit INSIDE the pane tree,\nreflowing with splits?}
  E -->|No — focused/modal/full-window| F["Companion window: own winit+wgpu (ADR-0086 path 3) — ship-now"]
  E -->|Yes — ambient, in a pane| G["Render-to-texture, sample back as a gpui image (ADR-0086 path 2)"]
  F --> H[Push gpui state as uniforms: time, res, mouse, accent token]
  G --> H

Route: gpui primitive → Vello vector → wgpu fragment pass, in that order of preference. A raw WGSL pass is justified only by real per-pixel cost. Companion-window is the ship-now path (it's the timeline-proto skeleton); in-window embed (render-to-texture) is the target for ambient surfaces — budget the round-trip honestly.

Core Rules

• Earn the GPU pass. Don't shader a button. Per-pixel work or nothing.
• Sample theme tokens. Color comes from u.accent (the gpui theme token pushed as a uniform) + a cosine palette() — never hardcode brand hex in WGSL, so light/dark + brand flow through.