xref: /plan9/sys/src/cmd/unix/drawterm/libmemdraw/alpha.hoc (revision 8ccd4a6360d974db7bd7bbd4f37e7018419ea908)
1*8ccd4a63SDavid du Colombierfunc f(x) {
2*8ccd4a63SDavid du Colombier	return x-x%1
3*8ccd4a63SDavid du Colombier}
4*8ccd4a63SDavid du Colombier
5*8ccd4a63SDavid du Colombierfunc pixel(dr, dg, db, da, sr, sg, sb, sa, m) {
6*8ccd4a63SDavid du Colombier	M = 255-f((sa*m)/255)
7*8ccd4a63SDavid du Colombier	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"
8*8ccd4a63SDavid du Colombier	return 0
9*8ccd4a63SDavid du Colombier}
10