"{\n"
" vec3 co = p*s;\n"
" vec2 r2 = rand_hash22(p.xz);\n"
-" vec3 grid = vec3(floor(co.x),co.y,floor(co.z)) * (1.0/s);\n"
+" vec3 grid = (vec3(floor(co.x),co.y,floor(co.z))+vec3(0.5,0.0,0.5)) * (1.0/s);\n"
"\n"
" float t1 = 1.0-t;\n"
" t1 = 1.0-t1*t1;\n"