Backgrounds are backdrops hand-drawn by Jim Bonacci that can be selected by users making levels in Happy Wheels. There are three backgrounds: Green Hills, City, and blank. You can also choose a color from the level options you want the background to be.
Green HillsGreen Hills is a background that seems to be out in the country. There are green hills in the background, and one large hill in the foreground.
CityThe city background is based on a huge city (possibly New York) with towering skyscrapers. This background is extremely unrealistic, though, because if you counted every story in the buildings, some would go beyond even 150 stories, with the tallest building having only 163, therefore, this city could be a futuristic city.
The blank background is simply a blank, white screen (unless the background color is set to a different color).
Background Color SelectorThere is a color selector for the background color in the level editor, which allows you to select any color possible as the background. It is exactly like the color selector for shapes and polygons. Whichever color you select, it will cover the background, and stay one solid color. However, the color only shows up when you test the level, so you will not see the color when you are editing the level. It was available since version 1.60.
- There is an exploitable glitch, where the background actually shows what is currently shown on your screen before you test it. This glitch happens when you load the LevelXML data with the "bg" value changed to a number above 2 (3, 4, 5, etc.). This only works in the editor, if you make the level public the entire level goes weird. If you try to go to the level options menu, it won't let you.
- If you go into the Demo Version and you load a level with the Green Hills background (this only works with green hills), if you zoom in three times on a hill (right click, then click on "Zoom In"), the screen will turn into the sky. If you zoom in 4 times, the entire screen will turn white. If you zoom in 5 times, it will turn back to normal.
- It has frequently been stated that one of the clouds in the Green Hills background resembles male genitalia.
- There are 3 layers of the green hills background: The main green hills, the background hills, and the sky. Movement affects how these move, as the first layer of hills will move much quicker than the sky in the background. The same goes with the city background, only the 2 closest layers are buildings instead of hills.
- In Happy Green Hills, a small character, barring the Elf, can fall through the log bridge, allowing you to go beneath the standard background limits, where the front-most layer of hills finishes, and the hills behind it can be seen. Due to the blue hue used for the background hills, the entire area seen underneath them follows the same colour.
Jim said that he or Caroline Pham might make more backgrounds, but it is unknown when or if these will be released.