In parallel projection, all lines of sight are parallel, the object is positioned at infinity and viewed from multiple points on an imaginary line parallel to the object. The 3-D object is transformed into a 2-D representation or a plane of projection that is an imaginary flat plane upon which the image created by the lines of sight is projected.
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Parallel Projections
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Parallel Projections
In a parallel projection:
Parallel lines on object
remain parallel on image
No diminution of size
Uniform foreshortening
Center of Projection is an infinite distance from projection plane parallel projectors
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Classes of Parallel Projections
C a v a li e r
C a b in e t
G e n e r a l
O b li q u e P r o je c t io n s
T r i m e t r i c
D im e t r ic
I s o m e t r ic
A x o n o m e t r ic
T o p
B o t t o m
F r o n t
B a c k
L e f t
R i g h t
M u lt iv ie w
O r t h o g r a p h ic P r o je c t io n s
P a r a l l e l P r o j e c t i o n s
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Parallel Projections