Producing this sketch usually requires a fair degree of artistic talent, which is why computer-generated set renderings are sometimes used to show the look and feel of a set. To determine the amount of space that a set may take up on stage, several factors must be considered. Obviously, the physical limitations of the stage must be taken into account. The height of the gridiron, width of the proscenium, and depth of the stage are the most important dimensions to consider. In addition to these limitations, sight lines must be considered.
Sight lines define the extremes of the stage area that the audience can see.
If a set is too big, not everyone in the audience will be able to see all of the action. In theatres that do not have permanent seating, such as Alden Hall at WPI, temporary seating is generally used. Since there is often no standard way for setting this seating up, the House Manager should be consulted so that sight lines may be determined. The ground plan is a top-down view of the stage, and shows the location of flats, platforms, etc. Also included are the locations of masking legs, fly system battens, etc.