This function will return the hue of the given colour. This is the "pure" colour tone which is part of the hue, saturation and value (luminosity) method for defining a colour. The following image illustrates how this value corresponds to the HSV scale of colour:
|col||The colour to check|
col = merge_colour(colour_get_hue(c_teal), c_white, 0.5);
The above code gets the hue used to make the colour constant "c_teal" and then merges it with white at a 50:50 ratio, storing the resulting colour in the variable "col".