|back||The index of the background to use.|
This function returns an array with the UV coordinates for the
texture on the texture page, filling in the array with the
following values:  = left,  = top,  = right and  =
bottom. This value can then be used in other draw functions,
particularly in general 3D and some of the
primitive functions, as well as the Shader functions.
var tex = background_get_uvs(back);
tex_left = tex;
tex_top = tex;
tex_right = tex;
tex_bottom = tex;
The above code will store the UV coordinates for the given background in a local array and then assign the values to instance variables.