1. Methods Anti-Aliasing Super Sampling
Multiple sample points across a finer grid to determine pixel intensity
High Resolution Computation
Low Resolution display
Obtain intensity information from multiple points that contribute to intensity of pixel.
Run Bresenham’s algorithm on microgrid.
Set pixel intensities
Aliasing
Distortion of information due to low frequency sampling
Under sampling
Anti-aliasing
Compensates for this distortion
If pixels have more than one intensity
Vary the intensity levels to compensate

2. SuperSampling Plot (0,0 to 2,1) Δx = 2, Δy = 1
Multiply both directions by 3 (adding a 3x3 grid)
Plotting (microgrid)
Δx = 8, Δy = 4
P0 = 2Δy – Δx = 0
K PK XK+1 YK+1
If PK < 0 plot XK+1, YK
PK+1 = PK +2Δy
Else plot XK+1, YK+1
PK+1 = PK +2Δy -2Δx

3. Anti-aliasing Normal weighting Anti-aliasing Weighted 1 7 3
1/3 1 7
2/3 7 3
At most 3 micro-pixels filled
4 levels of intensity (including off)
3 = full, 2 = 2/3, 1= 1/3, 0=0