twigl

twigl.app is an online editor for One tweet shader, with gif(or webm, jpeg, png) generator and sound shader, and broadcast live coding.

get started

$ npm install
$ npm start

screen shot

Example:

precision highp float;
uniform float time;
void main(){vec4 p=vec4((gl_FragCoord.xy/4e2),0,-4);for(int i=0;i<9;++i)p+=vec4(sin(-(p.x+time*.2))+atan(p.y*p.w),cos(-p.x)+atan(p.z*p.w),cos(-(p.x+sin(time*.8)))+atan(p.z*p.w),0);gl_FragColor=p;}

Live: DEMO

regulation

There are four modes in twigl.app, each of which has a sub-mode that uses GLSL ES 3.0, or in addition to it, a mode that enables MRT.

classic:

This mode is compatible with GLSLSandbox.

The uniform variables are "resolution", "mouse", "time", "frame", and "backbuffer".

geek:

In this mode, the various uniform variables are in a single-character style.

"r", "m", "t", "f", and "b", respectively.

geeker:

In this mode, there is no need to declare precision and uniform. They are automatically complemented on the implementation side. Otherwise, it is the same as in geek mode.

geekest:

In this mode, the description of "void main(){}" may be omitted (or not), and "gl_FragCoord" can be described as "FC". In addition, a variety of GLSL snippets are available.

The reason why we support the notation that does not omit the definition of the main function is to allow users to define their own functions.

For more information on snippets, please see below.

GLSL snippets in GEEKEST mode

twigl with geekest mode have included simplex-noise, you can call it as follows.

float f = snoise2D(v.xy);
float g = snoise3D(v.xyz);
float h = snoise4D(v.xyzw);

If you are more concerned with speed than accuracy, the following functions may be more appropriate.

// fract sin noise
float fsnoise(vec2 c){
    return fract(sin(dot(c, vec2(12.9898, 78.233))) * 43758.5453);
}

// fsnoise for macOS
float fsnoiseDigits(vec2 c){
    return fract(sin(dot(c, vec2(0.129898, 0.78233))) * 437.585453);
}

// for example
float i = fsnoise(v.xy);
float j = fsnoiseDigits(v.xy);

Other pre-defined constants and functions are as follows.

vec3 hsv(float h, float s, float v){
    vec4 t = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
    vec3 p = abs(fract(vec3(h) + t.xyz) * 6.0 - vec3(t.w));
    return v * mix(vec3(t.x), clamp(p - vec3(t.x), 0.0, 1.0), s);
}

mat2 rotate2D(float r){
    return mat2(cos(r), sin(r), -sin(r), cos(r));
}

mat3 rotate3D(float angle, vec3 axis){
    vec3 a = normalize(axis);
    float s = sin(angle);
    float c = cos(angle);
    float r = 1.0 - c;
    return mat3(
        a.x * a.x * r + c,
        a.y * a.x * r + a.z * s,
        a.z * a.x * r - a.y * s,
        a.x * a.y * r - a.z * s,
        a.y * a.y * r + c,
        a.z * a.y * r + a.x * s,
        a.x * a.z * r + a.y * s,
        a.y * a.z * r - a.x * s,
        a.z * a.z * r + c
    );
}

const float PI = 3.141592653589793;
const float PI2 = PI * 2.0;

Note that the above snippets are only available in GEEKEST mode.

keyboard shortcut

key	action
Alt + Enter	play sound
Ctrl + Alt + Enter	stop sound
Ctrl + Alt + v	vim mode
Ctrl + Alt + t	change view
Ctrl + Alt + .	up font size
Ctrl + Alt + ,	down font size

You can use Command instead Ctrl on the macOS.

credit

spite/ccapture.js: A library to capture canvas-based animations at a fixed framerate

jnordberg/gif.js: JavaScript GIF encoding library

Ace - The High Performance Code Editor for the Web

ashima/webgl-noise: Procedural Noise Shader Routines compatible with WebGL

Shadertoy BETA

interface design by @iY0Yi

license

MIT licensed.