To find and define the visual significance your project might have - i offer mood mapping and matte painting.
Get an overview of cultural background, time period and state of affairs ...
before your artists begins to build the actual game content.
I do mood mapping to define a world's mood - color value and lighting;
with out detailed drawings of each possible object or character it might hold.
The technique i use is "painting over simplified structure";
other forms, like photo manipulation, also possible - if the photo source is provided by the contract partner.
If you like to have us work out such contract or for any question regarding such
a contract : please contact us by eMail.