const vs = `
attribute vec4 position;
void main() {
gl_Position = position;
}
`;
const userShader = `
// FROM: https://www.shadertoy.com/view/4sdXDl
//spikey
#define SHAPE length(z.yz)
//normal
//#define SHAPE length(z.xyz)
//bizarro
//#define SHAPE length(z.yz-z.xx)
//etc...
#define HIGH_QUAL
#ifdef HIGH_QUAL
#define MARCH_STEPS 199
#else
#define MARCH_STEPS 99
#endif
float k=7.0+3.0*sin(iGlobalTime*0.15);
vec3 mcol=vec3(0.0);
void AbsBox(inout vec4 z){//abs box by kali
z.xyz=abs(z.xyz+1.0)-1.0;
z*=1.5/clamp(dot(z.xyz,z.xyz),0.25,1.0);
}
void Bulb(inout vec4 z, in vec4 c){//mandelBulb by twinbee
float r = length(z.xyz);
float zo = asin(z.z / r) * k + iGlobalTime*0.15;
float zi = atan(z.y, z.x) * 7.0;
z=pow(r, k-1.0)*vec4(r*vec3(cos(zo)*vec2(cos(zi),sin(zi)),sin(zo)),z.w*k)+c;
}
float DE(vec3 p){
vec4 c = vec4(p,1.0),z = c;
Bulb(z,c);
float r0=(length(z.xyz)-1.15)/z.w;
z.xyz-=1.0;
for(int i=0;i<7;i++)AbsBox(z);
float r=SHAPE;
mcol.rgb=vec3(1.0,0.5,0.2)+abs(sin(0.2*r+100.0*z.yxz/z.w));
return 0.5 * max((r-1.0) / z.w,-r0);
}
vec3 sky(vec3 rd, vec3 L){//modified bananaft's & public_int_i's code
float d=0.4*dot(rd,L)+0.6;
//return vec3(d);
rd.y+=sin(sqrt(clamp(-rd.y,0.0,0.9))*90.0)*0.45*max(-0.1,rd.y);
rd=abs(rd);
float y=max(0.,L.y),sun=max(1.-(1.+10.*y+rd.y)*length(rd-L),0.)
+.3*pow(1.-rd.y,12.)*(1.6-y);
return d*mix(vec3(0.3984,0.5117,0.7305),vec3(0.7031,0.4687,0.1055),sun)
*((.5+pow(y,.4))*(1.5-abs(L.y))+pow(sun,5.2)*y*(5.+15.0*y));
}
float rnd;
void randomize(in vec2 p){rnd=fract(float(iFrame)+sin(dot(p,vec2(13.3145,117.7391)))*42317.7654321);}
float ShadAO(in vec3 ro, in vec3 rd){
float t=0.0,s=1.0,d,mn=0.01;
for(int i=0;i<12;i++){
d=max(DE(ro+rd*t)*1.5,mn);
s=min(s,d/t+t*0.5);
t+=d;
}
return s;
}
vec3 scene(vec3 ro, vec3 rd){
vec3 L=normalize(vec3(0.4,0.025,0.5));
vec3 bcol=sky(rd,L);
vec4 col=vec4(0.0);//color accumulator
float t=DE(ro)*rnd,d,od=1.0,px=1.0/iResolution.x;
for(int i=0;i<MARCH_STEPS;i++){
d=DE(ro);
if(d<px*t){
float dif=clamp(1.0-d/od,0.2,1.0);
vec3 scol=mcol*dif*(1.3-0.3*t);
#ifdef HIGH_QUAL
vec2 s=vec2(DE(ro+d*4.0*L),DE(ro+d*16.0*L));
scol*=clamp(0.5*s.x/d+(s.y/d)/8.0,0.0,1.0);
#endif
float alpha=(1.0-col.w)*clamp(1.0-d/(px*t),0.0,1.0);
col+=vec4(clamp(scol,0.0,1.0),1.0)*alpha;
if(col.w>0.9)break;
}
t+=d;ro+=rd*d;od=d;
if(t>6.0)break;
}
col.rgb+=bcol*(1.0-clamp(col.w,0.0,1.0));
return col.rgb;
}
mat3 lookat(vec3 fw){
fw=normalize(fw);vec3 rt=normalize(cross(fw,vec3(0.0,1.0,0.0)));return mat3(rt,cross(rt,fw),fw);
}
void mainImage(out vec4 fragColor, in vec2 fragCoord) {
randomize(fragCoord);
float tim=iGlobalTime*0.3,r=2.0+cos(tim*0.7);
vec2 uv=(fragCoord-0.5*iResolution.xy)/iResolution.x;
vec3 ro=vec3(sin(tim)*r,sin(tim*0.4),cos(tim)*r);
vec3 rd=lookat(-ro)*normalize(vec3(uv,1.0));
//rd+=2.0*cross(qrt.xyz,cross(qrt.xyz,rd)+qrt.w*rd);
fragColor=vec4(scene(ro,rd)*2.0,1.0);
}
`;
// FROM shadertoy.com
const shadertoyBoilerplate = `
#extension GL_OES_standard_derivatives : enable
//#extension GL_EXT_shader_texture_lod : enable
#ifdef GL_ES
precision highp float;
#endif
uniform vec3 iResolution;
uniform float iGlobalTime;
uniform float iChannelTime[4];
uniform vec4 iMouse;
uniform vec4 iDate;
uniform float iSampleRate;
uniform vec3 iChannelResolution[4];
uniform int iFrame;
uniform float iTimeDelta;
uniform float iFrameRate;
struct Channel
{
vec3 resolution;
float time;
};
uniform Channel iChannel[4];
uniform sampler2D iChannel0;
uniform sampler2D iChannel1;
uniform sampler2D iChannel2;
uniform sampler2D iChannel3;
void mainImage( out vec4 c, in vec2 f );
${userShader}
void main( void ){
vec4 color = vec4(0.0,0.0,0.0,1.0);
mainImage( color, gl_FragCoord.xy );
color.w = 1.0;
gl_FragColor = color;
}
`;
const $ = document.querySelector.bind(document);
const camera = new THREE.Camera();
camera.position.z = 1;
const scene = new THREE.Scene();
const geometry = new THREE.BufferGeometry();
const vertices = new Float32Array([
-1, -1,
1, -1,
-1, 1,
-1, 1,
1, -1,
1, 1,
]);
geometry.addAttribute( 'position', new THREE.BufferAttribute( vertices, 2 ) );
const uniforms = {
iGlobalTime: { type: "f", value: 1.0 },
iResolution: { type: "v3", value: new THREE.Vector3() },
};
const material = new THREE.RawShaderMaterial({
uniforms: uniforms,
vertexShader: vs,
fragmentShader: shadertoyBoilerplate,
});
var mesh = new THREE.Mesh(geometry, material);
scene.add(mesh);
var renderer = new THREE.WebGLRenderer();
document.body.appendChild(renderer.domElement);
resize(true);
render(0);
function resize(force) {
var canvas = renderer.domElement;
var dpr = 1; //window.devicePixelRatio; // make 1 or less if too slow
var width = canvas.clientWidth * dpr;
var height = canvas.clientHeight * dpr;
if (force || width != canvas.width || height != canvas.height) {
renderer.setSize( width, height, false );
uniforms.iResolution.value.x = renderer.domElement.width;
uniforms.iResolution.value.y = renderer.domElement.height;
}
}
function render(time) {
resize();
uniforms.iGlobalTime.value = time * 0.001;
renderer.render(scene, camera);
requestAnimationFrame(render);
}
canvas {
border: 1px solid black;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r74/three.min.js"></script>
