w:_(r:16%9)*h:900;s:w,h;v:(r*2),-2 0;c:0 0 -1-v%2
S:{a:+/x*x;$[d:(h*h:+/x*y)-a*c:(+/y*y)-z*z;(h-%d)%a;0]}
R:{$[0<h:S[x;0 0 -1-y;0.5];o[0 0 1+h;h:y+x*h]%2;0<t:((y-2)%x)1;@[&3;1+~/(1<2!)'(y+t*x)0 2;:;1];1-0.7 0.5 0*x@1]}
"r.ppm"0:("P3";`k@s;$255),,/{(!w){`k@_255*R[;&3]c+v*,[;0](1+2*x,y)%2*s}' \x}'!h
over 1 year ago