Week 2 - 3D Graphics: Crash Course CS #27

This is a devlog for week two of Game Development.

1. Why do we rely on triangles instead of quads (squares) in 3D graphics?

This is because in 3D graphics, simplicity in key. 3 points in space are the least amount of points needed to define a plane. Two points are not enough to define a polygon in 3D space, and 4 points essentially add complexity and are not guaranteed to define a plane.

2. What's the difference between Painter's Algorithm vs Z-Buffer?

Painter's Algorithm arranges all polygons in the scene from farthest to nearest and then renders them in that order. Z Buffering does not need to sort through polygons so it is much faster. All pixels are initialized at infinity and then the Z-buffer check the distance of the polygon, updating it. Sadly , later and closer polygons might not override other polygons. Z Buffer can also cause Z-Fighting if 2 polygons have the same distance.

3. What is the surface normal on the floor in Vector 3 notation? What is the surface normal of your face?

The surface normal refers to an angle perpendicular to a polygons surface.  The surface normal of the floor is an angle facing directly upwards towards the ceiling. Our faces have many different surfaces that make up its structure, so we have a surface normal for each polygon that makes up our faces.

4. Pick a part of the video where you thought either "wow that makes so much sense" or "wtf is that, why would you do that?"

I was really intrigued by the part about anti-aliasing. I always have seen the word pop up in game settings, but never knew what it meant till today. I even tested it out to see its effect, and just like the video said, disabling it caused the graphics to become more jagged. It's just really interesting to think that angle and curves aren't actually created solely by the arrangement of pixels on your screen, but also by the color of the pixels as well, giving shapes a much more organic feel to them.