This is an implementation of basic PBR materials. The X coordinate defines the roughness of material and the Y defines how metallic it is. The implementation is based of Epic Games presentation of 201…
for(_=`3.~or|atZ1)Y.0YXionWvecRR2Qt(O;}NinMOyKfloZJJ(MK.HufferG+2.)/&(pow(%ttrib$hader#),!)!R3()*v.xmax(0.,doO=i,R3 1.creZeS#(=3563x!K-r.x(-*t)+t)return ArrayBG(k0,!Ztachp!compile Oi,-m,gl_FragConif|mertexA$void maM(){Program(s#Source(=n|malize(with(g)T=k=34962,v3!"a$ute Q v;gl_PositW=R4(v-,YN"!f2!"precisW lowp J;u J T;Q v,y=Q(Y;Oi,y,d){x=,.2,.1!m=mix(.1!x,v.y!ry+d!l=m+mpowy,r5.);J n=*,f=n*n,prcdgyt=(n+(n+)/8.;x*.06+(lv.yx/~+f/%p*p*(f-)+,2.~l*c/(c*g/(g/~*c*g,X~*cNJ Ov){y=mod(y,y)-.5*y,length(v)-.46Nm|d.xy/640.-.5,1y=-8!f;f|(Mt x=0;x<200;++x){J c=K);if(c<X{Q r=Q(X;v=Q(Hx&Y/~,Hy&2))/2.,.Y;iK)-K-r.yxyxy)));f=cos(T!.5,sM(T)))+-.4,-1,-Y);breakNy+=m*cNl|=R4%f/(f+!.5YN" v f=!v,f!lMkp!usep!bMd,bGDZa(k,new Int8([6,6,0]!35044!enableV(0!vPoMter(2,5122,0!(x=()=>{u1f(getULocZW(p,'T'!T+=.005!draws(4,3!setTimeouOx)})()`;G=/[^ "'-FILPS-V[-{}]/.exec(_);)with(_.split(G))_=join(shift());eval(_)
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