Two-point Perspective
Two-point perspective can be used to draw the same objects as one-point perspective, rotated: looking at the corner of a house, or looking at two forked roads shrink into the distance, for example. One point represents one set of parallel lines, the other point represents the other. Looking at a house from the corner, one wall would recede towards one vanishing point, the other wall would recede towards the opposite vanishing point.
Two-point perspective exists when the painting plate is parallel to
a Cartesian scene in one axis (usually the z-axis) but not to the other
two axes. If the scene being viewed consists solely of a cylinder
sitting on a horizontal plane, no difference exists in the image of the
cylinder between a one-point and two-point perspective.
more: http://en.wikipedia.org/wiki/Perspective_(graphical)
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