Three- dimensional Foreshortening
Solving the foreshortening of an assembled three-dimensional object or box set is an occasional problem. The nineteenth- century techniques of Paulo Landriani (p. 130) are a good example of the use of a top and side view to develop the foreshortened elevations of a box setting. Dimensions from the new smaller plan are transposed into the elevation of the foreshortened wall and its new vanishing point, FW-VP.
The same technique is applied to a contemporary problem. A small assembled unit of scenery, such as a bus stop shelter (p. 139) is foreshortened to occupy less space on the stage. Again, the alignment of a top view and side view provides the means to put together a front view (3). It is not a perspective view, contrary to what its location between the top view and OP might suggest. The disassembled view or development is achieved with dimensions and spacing present in the various views.
Although OP is on the center line of the object in this example, it can be set up to the right or left depending on the position of the object on the stage.
All the examples that have been shown dealt with the foreshortening of actual size whether it be a room or unit of architecture. The designer frequently uses perspective in the opposite procedure. It may begin in the sketch. The perspective is sharpened in an effort to get a greater sense of space or scale into the design. If the sketch has been developed by the perspective floor grid technique it is easy to use information from the sketch and plan to find the true shape of foreshortened scenic elements.
The example of foreshortened scenery shown on page 140 is a simple exterior setting. The first drawing shows the plan and sketch relationship. Note that there are two sets of vanishing points for each plane of the set numbered 1 through 4. BVP is the normal vanishing point for each unit and T-VP is the foreshortened VP of the tops. All foreshortening takes place above the horizon line and none below. If HL is established at six feet or higher the foreshortening is above the actor and the stage floor remains flat.
The amount of foreshortening is decided by the designer in the sketch. The