Key Concepts:
In a two-dimensional space, a sense of depth, of three dimensions, can be achieved only by means of illusion.
Devices for Creating the Illusion of Three-Dimensional Space
· Overlapping
· Diminishing Scale
· Vertical Placement
· Linear Perspective
· Aerial or Atmospheric Perspective
· Modeling
Key Terms:
shape - In two-dimensional media, a flat area, the boundaries of which are measured in terms of height and width.
mass - Any solid that occupies a three-dimensional area or volume, measured in terms of three dimensions: height, width and depth.
two-dimensional space - Any space that is flat, possessing height and width, but no depth, such as a piece of drawing paper or a canvas.
three-dimensional space - Any space that possesses height, width, and depth.
geometric shape – precise and regular
shape that can be defined by mathematical formula. Examples are such
things as circles, squares, triangles, hexagons. These are the kinds of
shapes we often find in man-made objects.
organic shape – irregular, often curved or rounded shape. Typically organic shapes are more relaxed and informal than geometric shapes. A shape that resembles living matter or objects found in nature.
negative shape or space - Empty space, surrounded and shaped so that it acquires a sense of form or volume.
scale - The comparative size of a thing in relation to another like thing or its "normal" or "expected" size.
overlapping - A way to create the illusion of space by placing one figure behind another.
picture plane - The flat , two-dimensional surface of a painting.
linear perspective - A system for depicting three-dimensional space on a two-dimensional surface that depends on two related principles: that things perceived as far away are smaller than things nearer the viewer, and that parallel lines receding into the distance converge at a vanishing point on the horizon line.
horizon line – A line, either shown or theoretical, at the observer’s eye level, where the earth meets the sky. The vanishing point(s) are located on the horizon line.
vanishing point - In linear perspective, the point on the horizon line where parallel lines appear to converge.
one-point linear perspective - A version of linear perspective in which there is only one vanishing point in the composition.
two-point linear perspective - A version of linear perspective in which there are two (or more) vanishing points in the composition.
foreshortening - The modification of perspective to decrease distortion resulting from the apparent visual contraction of an object or figure as it extends backwards from the picture plane at an angle approaching the perpendicular.