stc.x=floor(stc.x*shadow_res.x+fract(stc.y*shadow_res.y*12345))/shadow_res.x;// add some chaotic jitter to X sample pos according to Y to disguise the snapping going on here
stc.x=floor(stc.x*shadow_res.x+fract(stc.y*pos_screen.y*3.14159))/shadow_res.x;// add some chaotic jitter to X sample pos according to Y to disguise the snapping going on here
stc.x=floor(stc.x*pos_screen.x+fract(stc.y*pos_screen.y*0.666666666))/shadow_res.x;// add some chaotic jitter to X sample pos according to Y to disguise the snapping going on here