ref: 2894b8f250339d56c4970a985d9f878bae91b138
dir: /libmemdraw/alpha.hoc/
func f(x) { return x-x%1 } func pixel(dr, dg, db, da, sr, sg, sb, sa, m) { M = 255-f((sa*m)/255) print f((sr*m+dr*M)/255), " ", f((sg*m+dg*M)/255), " ", f((sb*m+db*M)/255), " ", f((sa*m+da*M)/255), "\n" return 0 }