21 Perspective Drawing
Perspective Drawing
In Illustrator CS5, you can easily draw or render artwork in perspective using a feature set that works on established laws of perspective drawing.
Perspective grid allows you to approximately represent a scene on a flat surface, as it is naturally perceived (by the human eye). For example, a road or a pair of railway tracks, which seem to meet or vanish in the line of vision.
Perspective grid presets
Illustrator provides presets for one-point, two-point, and three-point perspectives.
One-point perspective
There is only one vanishing point, which is identical to the principal point located on the horizon line and the median line. This type of perspective is typically used for images of roads, railway tracks, hallways, or buildings viewed so that the front is directly facing the viewer. Any objects that are made up of lines either directly parallel with the viewer’s line of sight or directly perpendicular (the railroad slats) can be represented with one-point perspective. These parallel lines converge at the vanishing point.
It is important to remember that the horizon is at the same height as are the eyes of the observer (y=y’=0). No matter where the characters of the same height are positioned, the horizon always cuts them at the same height.
Two-Point Perspective
Two-point perspective (2PP): there are two vanishing points, neither of which is the principal point, that define a single vanishing line, usually (but not necessarily) the horizon line. 2PP requires that two faces of all square solids must be perpendicular (not parallel) to the image plane and parallel (not perpendicular) to the direction of view.
It is important to remember that the horizon is at the same height as are the eyes of the observer (y=y’=0). No matter where the characters of the same height are positioned, the horizon always cuts them at the same height.
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