Class 12: How 3D Computer Graphics Works

During this assignment i watched an overview video on YouTube highlighting some of the key points and basics of how 3D Computer Graphics works.  As i was watching this video, it was very informative.  It broke each subject down into 3 parts; vertex points/vertices, polygons, and lighting/normals.  Before watching the video i didn't really have any idea what any of those things were used for in 3D tutorial video, but since i watched it i now have a better idea of how these things work and what they are used for.  Down below is an overview of what i learned and some of the screenshots from this particular video to help with explaining which parts i am actually referring to.

The video started out by explaining what vertex points are.  They pretty much are unconnected dots on a screen that eventually will be connected to form a triangle or polygon.  This is what is known as 3D Geometry.  In the video it explained how it is very important because anything we see in a video game or a computer game uses 3D Geometry to make up these particular points, which are then connected to form a shape of whatever it is we are seeing in the game/animation.

The next part of the video i watched was polygons and texture mapping.  As you guys can see in the picture above the outline of the video game character that is pictured is composed of many small polygon/triangle shapes that are made by connecting the dots which was seen before in the part about 3D Geometry.  This combination of polygons is known as a Polygonal mesh, which is then texture mapped, in this case with some barbarian type of skin/armor to appear as what the game designers want it to look like as people play this particular game.

One of the last and final parts the video talked about was lighting and normals.  The subject lighting is pretty straight forward.  From this picture we can see a small light was put in front of the video game character, which then causes the front of the character to be lit up and more visible than the back half of the character.  In this part Normals come into play by making this kind of thing happen; it is done by using a vector, which is more or less a line/arrow that points out of each small polygonal plane that constructs the whole full video game character.  The more directly this line is pointing toward the light source that will be introduced, the brighter that character will appear on the screen.  In the video the front of the character has vectors that are pointing toward the light, which allows us to see the characters armor and face.  Also the vectors on the back of the characters are pointing away from the light causing them to appear much darker, giving it a shaded look.