Today in class we
Sprites are small image animations, like an animated GIF, often
used in video game contexts. If you want a character to be
rendered with a raster image, and want it to have some small
amount of animation, you can depict that animation with a small
amount of static images which will act as the frames of the
animation. Then when you want to draw and move around the
character (which you do in Processing with
the image() command), you can use code to make the
sprite move.
When a character is not moving, you can render it with one static image. And when a character is moving (either moved by the user or on its own) you can render it with the animated sprite.
You can even have different sprites for different kinds of motions. This is useful if, for example, you wanted a character to appear like they were running to the left or right when the user moved them in that direction.
Collision detection is one of the key features of nearly all video games. You want to be able to detect if characters are touching each other, touching things to hinder movement, or touching other objects that they may want to capture or avoid.
At its simplest, you can do collision detection with
the dist() command. This works really well for
characters and objects rendered as round shapes. It does not
seems as accurate when you have characters or objects rendered
in more complicated ways. If dist()-based collision
detection really is not sufficient for the shapes you're using
and for your game play, we can talk about some more advanced
techniques, for example using something like
this algorithm
for detection overlapping polygons.