Scan Conversion

Question 1

How does Bresenham’s Algorithm approximate a line?

Answer 1

Y = mX + c

For every increment in X

Work out the real Y-Value

Round Y to the nearest integer

Question 2

How might we Scan Convert a triangle?

Answer 2

Start at the intersection of two edges

Increment the Y-Value, and figure out how the X Value for each of the edges changes by doing this

Fill in the pixels between the two X Values for each edge

Question 3

How can we perform Hidden Surface Removal using a Depth Buffer?

Answer 3

The Depth Buffer is used to keep track of how far each pixel is from the observer

This means when we generate a new pixel we can check if it is closer to us, than some previous pixel and only render it if it is closer

Question 4

What is Z Fighting in the Z Buffer?

Answer 4

This is when two surfaces are fairly close to each other,

and so bleed into each other when being rendered

because both surfaces are “fighting” to be in the Z-buffer