README.md

Note

This is one of 199 standalone projects, maintained as part of the @thi.ng/umbrella monorepo and anti-framework.

🚀 Please help me to work full-time on these projects by sponsoring me on GitHub. Thank you! ❤️

• About
• Status
• Related packages
• Installation
• Dependencies
• Usage examples
• API
• Authors
• License

About

Basic WebGL scaffolding for running interactive fragment shaders via @thi.ng/shader-ast. This is a support package for @thi.ng/webgl.

Status

ALPHA - bleeding edge / work-in-progress

Search or submit any issues for this package

Related packages

• @thi.ng/shader-ast - DSL to define shader code in TypeScript and cross-compile to GLSL, JS and other targets
• @thi.ng/shader-ast-stdlib - Function collection for modular GPGPU / shader programming with @thi.ng/shader-ast
• @thi.ng/webgl - WebGL & GLSL abstraction layer

Installation

yarn add @thi.ng/webgl-shadertoy

ESM import:

import * as ws from "@thi.ng/webgl-shadertoy";

Browser ESM import:

<script type="module" src="https://esm.run/@thi.ng/webgl-shadertoy"></script>

JSDelivr documentation

Package sizes (brotli'd, pre-treeshake): ESM: 693 bytes

Dependencies

• @thi.ng/api
• @thi.ng/shader-ast
• @thi.ng/shader-ast-glsl
• @thi.ng/webgl

Note: @thi.ng/api is in most cases a type-only import (not used at runtime)

Usage examples

Three projects in this repo's /examples directory are using this package:

Screenshot	Description	Live demo	Source
	Shader-AST meta-programming techniques for animated function plots	Demo	Source
	Evolutionary shader generation using genetic programming	Demo	Source
	Shadertoy-like WebGL setup	Demo	Source

API

Generated API docs

import {
    $xy, add, distance, eq, float, FloatSym, fract,
    int, min, mix, mul, neg, ret, sin, sym,
    Vec2Sym, Vec2Term, vec3, Vec3Sym, vec4
} from "@thi.ng/shader-ast";
import { aspectCorrectedUV, fit1101 } from "@thi.ng/shader-ast-stdlib";
import { glCanvas } from "@thi.ng/webgl";
import { MainImageFn, shaderToy } from "@thi.ng/webgl-shadertoy";

const mainImage: MainImageFn = (gl, unis) => {
    // predeclare local vars / symbols
    let uv: Vec2Sym;
    let mp: Vec2Sym;
    let d1: FloatSym;
    let d2: FloatSym;
    let col: Vec3Sym;

    // Inline function to create ring pattern with center at `p`
    const rings = (p: Vec2Term, speed = 0.25, freq = 50) =>
        sin(mul(add(distance(uv, p), fract(mul(unis.time, speed))), freq));

    return [
        // let's work in [-1..+1] range (based on vertical resolution)
        (uv = sym(aspectCorrectedUV($xy(gl.gl_FragCoord), unis.resolution))),
        (mp = sym(aspectCorrectedUV(unis.mouse, unis.resolution))),
        // compute ring colors
        (d1 = sym(rings(mp))),
        (d2 = sym(rings(neg(mp)))),
        // combine rings and multiply with target color based on
        // mouse button state
        (col = sym(
            mul(
                vec3(fit1101(min(d1, d2))),
                mix(
                    vec3(1),
                    vec3(d1, 0, d2),
                    float(eq(unis.mouseButtons, int(1)))
                )
            )
        )),
        // return as vec4 (mandatory)
        ret(vec4(col, 1))
    ];
};

// create WebGL canvas
const canvas = glCanvas({
    width: window.innerWidth,
    height: window.innerHeight,
    parent: document.body,
    version: 1
});

// init shader toy with canvas & shader fn
const toy = shaderToy({
    canvas: canvas.canvas,
    gl: canvas.gl,
    main: mainImage
});

toy.start();

Authors

• Karsten Schmidt

If this project contributes to an academic publication, please cite it as:

@misc{thing-webgl-shadertoy,
  title = "@thi.ng/webgl-shadertoy",
  author = "Karsten Schmidt",
  note = "https://thi.ng/webgl-shadertoy",
  year = 2019
}

License

© 2019 - 2024 Karsten Schmidt // Apache License 2.0