definition
The mass or shape of an object or of objects which appear unified.
types
2-Dimensional Shape - the presence of an area or areas which contrast in color and/or texture from adjacent areas creating a two-dimensional shape in the landscape.
3-Dimensional Mass - the volume of a landform, natural object, or manmade structure in the landscape.
subelements
Geometry - the extent to which a form approaches a standard geometrical figure of two or three dimensions e.g., square, circle, triangle, cube, sphere, cone, etc.
Complexity - the degree of simplicity or intricacy of a form, Simpler forms tend to be regular, and complex forms to be irregular.
Orientation - the relationship of the form to the horizontal axis of the landscape (e.g., vertical, horizontal, diagonal, nondirectional), or to the points of the compass (e.g., north-south, ENE WSW).
suggested vocabulary
Bold/definite/indistinct Prominent Flat/rolling/rugged Rounded/angular Rough/smooth Jagged/domed/flattened Steep/moderate/gentle Solid/transparent Simple/complex Amorphous/geometric Regular/irregular Narrow/wide Long/short/tall High/low	Diverse/numerous/few Large/small Convex/concave Circular/oval Square/rectangular/rhomboid Triangular/trapezoid Linear/parallel/curving Conical/cylindrical/cubic Pyramidal/spherical Contrasting/compatible Vertical/horizontal/diagonal Nondirectional Symmetrical/asymmetrical Strip/block/patch
dominance
Forms that are bold solid or vertical tend to be dominant in the landscape
variable effects
Viewing Angle - the visual proportions of forms change with the direction and angle of viewing, due to perspective effects. Two-dimensional forms become foreshortened with lower observer positions and oblique viewing angles. Three-dimensional forms appear to diminish towards the horizon, especially with oblique viewing angles.
Lighting - frontlighting and backlighting tend to flattened three-dimensional forms. Backlighting may emphasize two-dimensional silhouettes. Sidelighting enhances three-dimensional effect.
Movement - the eye is attracted to movement in the landscape, e.g., such changing forms as waterfalls, steam from cooling towers, or smoke plumes