background_colour
Returns: Real
When in a room, it can have no background image selected for any
of its background_index, in which
case you should set a background colour with this variable and make
sure that the background_showcolour
variable is set to true so it can be seen. Having a room
with no background image and no background colour will
result in graphical artefacts being drawn on the screen and is not
recommended.
if background_index[0] = -1
{
background_colour= c_black;
background_showcolour = true;
}
The above code checks to see if background0 has an image assigned to it and if not it sets the background colour to black and flags it to be shown.