Using the background

We have done the tricky stuff, so this will be simple. There are three steps, as follows:

1. Create a VertexArray.
2. Initialize it after leveling up each wave.
3. Draw it in each frame.

Add the following highlighted code to declare a VertexArray instance called background and load the background_sheet.png file as a texture:

// Create an instance of the Player class
Player player;
// The boundaries of the arena
IntRect arena;
// Create the background
VertexArray background;
// Load the texture for our background vertex array
Texture textureBackground;
textureBackground.loadFromFile("graphics/background_sheet.png");
// The main game loop
while (window.isOpen())

Add the following code to call the createBackground function, passing in background as a reference and arena by value. Notice that, in the highlighted code, we have also modified the way that we initialize the tileSize variable. Add the highlighted code exactly as shown:

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