03/13/2003
15-462 Graphics I
6
Bresenham’s Algorithm II
•Decision
variable a – b
–If a –
b > 0 choose lower pixel
–If a –
b · 0 choose higher pixel
•Goal:
avoid explicit computation of a – b
•Step
1: re-scale d = (x2 – x1)(a
– b) = Dx(a – b)
•d is
always integer
