SFML vertex arrays and sprite sheets

We are nearly ready to implement the scrolling background. We just need to learn about SFML vertex arrays and sprite sheets.

What is a sprite sheet?

A sprite sheet is a set of images, either frames of animation or totally individual graphics, contained in one image file. Take a closer look at the sprite sheet that contains four separate images that will be used to draw the background in Zombie Arena:

SFML allows us to load a sprite sheet as a regular texture in exactly the same way we have done for every texture in the book so far. When we load multiple images as a single texture, the GPU can handle it much more efficiently.

Tip

Actually a modern PC could handle these four textures without using a sprite sheet. It is worth using these techniques as our games are going to start getting progressively more demanding on the hardware.

What we need to do when we draw an image from the sprite sheet is make sure we refer to the precise pixel coordinates of the part...