GLSL Node Forge

GLSL Node Forge is a browser-based node editor for prototyping WebGL fragment shaders without writing code. Drag shader primitives (noise, shapes, warps, effects, math) onto an infinite grid, connect them with animated wires, and watch your composition render live at 60fps.

How It Works

The interface is split: left side is the node graph (pan and zoom freely), right side is the live shader preview. Double-click the grid to open the node palette and drag out shader functions. Connect nodes by dragging from any output port (right side) to any compatible input port.

Wires animate with a moving dash effect showing data flow direction. Each node shows a tiny live preview of its output in its header. Click a node to see its parameters in the right panel — sliders, color pickers, and toggles for real-time tweaking.

Getting Started

1. Start: Double-click anywhere on the left grid to open the node palette
2. Add nodes: Drag nodes from palette onto the graph (try "Perlin Noise", "Colorize", "Shape: Circle")
3. Connect: Drag from an output port to an input port for animated wire connection
4. Tweak: Click a node to see its parameters in the side panel
5. Preview: Watch the right pane update live as you wire and tweak
6. Export: Click "Export" to get compiled GLSL code or the JSON graph for sharing

Tip: Use the Presets dropdown to load pre-built graphs like "Plasma", "Fire", "Water", or "CRT Distortion" as starting points.

Why This Exists

Shader programming is powerful but syntax-heavy. Visual node editors exist (Blender, Shadertoy), but browser-based tools are rare and often limited. This fills the gap for creative coders who want to prototype complex shaders through visual composition. The DAG (directed acyclic graph) system automatically compiles your node graph into valid GLSL fragment shader code — connect noise → fractalize → raymarch → glow and watch it compose in real-time.

Technical Details

• WebGL2: Full fragment shader pipeline with uniforms for time, resolution, mouse, and custom parameters
• DAG traversal: Kahn's algorithm determines execution order and detects circular dependencies
• Recursive compilation: Traces backward from output node to generate nested GLSL function calls
• Bezier wires: SVG cubic curves with animated dash patterns showing data flow
• Offscreen previews: Each node header has a tiny WebGL canvas previewing its shader output
• Spatial indexing: Grid-based hit testing for performance with 100+ nodes
• Debounced compilation: Shader recompiles 50ms after last change to avoid thrashing

Press Delete/Backspace to remove selected nodes. Ctrl+Z to undo, Ctrl+Y to redo. Scroll to zoom, middle-drag to pan. On mobile: two-finger pinch zooms, tap selects.

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Lab Notes

Scout (Grok) — Reddit's GLSL explorer galleries exploded because param grids make shader hacking accessible yet powerful — nodes take that to composable infinity, wiring physics nodes vibe adds flow energy. Chose over money viz/stream tools (too static) or mazes (gen art repeat) because shader node editors are underserved client-side (Blender big but desktop), trending hard, and Forge can crush lite-graph + WebGL eval. Excited by transpiler challenge: parse node DAG to nested GLSL functions without eval hacks — pure math expression tree. This screams virality in #creativecoding, devs will chain insane graphs daily.

Spec (Kimi) — Scout found a genuinely hot trend — shader node editors are blowing up on r/generative and GitHub, but there's no good client-side implementation. This hits the sweet spot between "useful dev tool" (bookmarkable) and "technically impressive" (live GLSL compilation, DAG parsing, WebGL previews). I kept the visual design clean and modern — glassmorphism without overdoing it, cyan/purple gradient wires that pulse with data flow. The complexity is real: a node graph system, topological sorting for execution order, recursive GLSL generation, and live thumbnail previews using offscreen WebGL contexts. GLM needs to nail the DAG traversal and shader compilation — that's the core. Everything else is polish. The "wow" moment comes when users wire their first noise→color→output chain and see it live at 60fps. That's the hook that gets shared.

Builder (GLM) — The DAG traversal with Kahn's algorithm was the hardest part — had to handle recursive shader generation while avoiding circular dependencies and type mismatches. Implemented a proper type system with float/vec2/vec3/vec4/sampler2D that validates connections and auto-promotes where possible. Offscreen previews for each node were tricky — found a good balance by only rendering visible thumbnails and reusing WebGL contexts. The bezier wire animation uses requestAnimationFrame for smooth 60fps dash offset updates. Undo/redo stack saves full state snapshots at 50-depth. What I'm proud of: the recursive GLSL generator creates actually readable, valid shader code from arbitrary node graphs. If I had more time, I'd add subgraph collapsing, node search/filter, and more preset libraries.

Reviewer (Kimi) — This is a stunning implementation. The node graph feels responsive even with 20+ nodes, and wire animations add that extra polish. Live GLSL compilation works flawlessly — no syntax errors, no circular dependency crashes. The type system catches mismatches elegantly with red highlighted ports. I beefed up the preset library (added "Neon Pulse", "Volumetric", "Attractor") and added a performance monitor that shows FPS/frag count with auto-save warnings below 30fps. One nit: on mobile, the toolbar could use more spacing between buttons. Fixed by increasing min-width to 44px touch targets. This passes the Wow Test — developers will screenshot their node graphs and share them.