Sprites

In computer graphics, a sprite is a two-dimensional bitmap that is part of a larger scene (e.g., a 2D video game). Sprites can be static images or animated graphics.

Sprites were the standard way to integrate graphics into video games in the 1980s and 1990s. Every character and object in the game was represented by a sprite that the game’s designer created. In modern times, 2D sprites have been replaced by 3D polygons because of the superior graphics rendering power that is available.

Sprites are also used to represent icons as part of a user interface.

Scratch

Every Scratch program is made up of sprites and the scripts (instructions) that control them. Scripts are programmed to make the sprites do things. Sprites can be made to move around, change their appearance, react when they touch things, and be controlled by the player. Sprites can also be programmed to talk in speech bubbles and play sounds and music. A project can have lots of sprites, and each sprite can have lots of scripts. Games are more exciting when there are more sprites to hit, dodge, or chase each other.

Bonus: creating a sprite in Python

Now we’re ready to make our first sprite. In Pygame, sprites are objects. If you haven’t worked with objects in Python before, they are a convenient way of grouping data and code into a single entity. It may be a little confusing at first, but fortunately, Pygame sprites are a good way to practice with objects and get used to how they work.

We start by defining our new sprite:

class Player(pygame.sprite.Sprite):

class tells Python we’re defining a new object, which is going to be our player sprite, and its type is pygame.sprite.Sprite, which means it will be based on Pygame’s pre-defined Sprite class.

The first bit of code we need in a class definition, is the special __init__() function, which defines what code will run whenever a new object of this type is created. There are also two properties that every Pygame sprite must have: an image and a rect:

class Player(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.Surface((50, 50))
        self.image.fill(GREEN)
        self.rect = self.image.get_rect()

The first line, pygame.sprite.Sprite.__init__(self) is required by Pygame - it runs the built-in Sprite classes initializer. Next, we define the image property - in this case, we’re just creating a simple 50 x 50 square and filling it with the color GREEN. in a future post we’ll learn how to make the sprite’s image be something fancier, like a character or spaceship, but a solid square is good enough for now. To move a sprite, we can use x, y, z coordinates that are implemented in Python.

You don’t have to know everything that I mentioned in this post, understanding the concept of sprites is our goal. :)