Directable lighting method and apparatus

A method for a computer system includes receiving a plurality of values for an illumination parameter associated with an illumination source for a scene, determining a plurality illumination contributions for a surface of an object within the scene, in response to the plurality of values, determining a plurality of texture maps associated with the surface of the object in response to the plurality of illumination contributions, wherein each of the plurality of texture maps is associated with each of the plurality of values for the illumination parameter, receiving a value for the illumination parameter at render time from a user, determining a texture map associated with the surface of the object, in response to the value for the illumination parameter and in response to the plurality of texture maps, rendering the surface of the object using the texture map to form an image, and displaying the image to the user.