03/18/2003
15-462 Graphics I
7
Antialiasing with Multiple Polygons
•Initially,
background color C0, a0 = 0
•Render
first polygon; color C1 fraction a1
–Cd = (1 – a1)C0 + a1C1
– ad = a1
•Render
second polygon; assume fraction a2
•If no
overlap (a), then
–C’d = (1 – a2)Cd + a2C2
– a’d = a1 + a2
