twigl

twigl.app is an online editor for One tweet shader, with gif(or webm) 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(){}" can be omitted, and "gl_FragCoord" can be described as "FC". In addition, a variety of GLSL snippets are available.

For more information, 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