Post on 31-Dec-2015
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Perspective Projection
During the Renaissance artists became interested in making two-dimensional artwork look three-dimensional.
Renaissance- (1450-1600): The Renaissance began in Italy and spread through Northern Europe. Art, Science, and Literature grew during this time.
Artists used mathematics and close observation to invent linear perspective. Linear perspective allows artists to trick the eye into seeing depth on a flat surface.
Perspective Projection
Perspective► A perspective drawing closely resembles what the eye
can actually see. It is an accurate 3D drawing.
► Objects that are the same size appear smaller in the distance almost like an optical illusion. (Father Ted)
► Examples are the fence posts in the distance. They appear smaller in the distance although the are the same size.
The Sun rises and sets on the horizon
The horizon line represents the very end of our vision
Have you noticed that the sun set always appears to be at the same
height as you areThis also means that the height of the spectator is the same height as
the horizon line
The horizon line is a line on the picture plane at the eye level of the spectator.
Horizon line below the object.
Horizon line above the object.
Horizon line
Horizon line
Horizon line
Centre line of vison
Spectator
Picture Plane
Elevation
Plan
Spectator’s View
Centre line of vison
Picture Plane
Terms Used In Perspective Drawing
• If you look straight ahead you will see things in focus but objects over to one side will not be clear unless you turn your head.
• Similarly in perspective this area exists which is 30° to the centre line of vision.
The Cone Of Vision
Centre line of vison30°
Distorted
Distorted
Spectator
Ground line
Vison in focus
30°
30°
30°Centre line of vison
Distorted
Distorted
Spectator
Vison in focus
The Cone Of Vision
The Picture PlaneAs with all projection systems the image is projected onto a plane.
The picture plane can be positioned in three areas;
• Between the spectator and the object.• Passing through the object.• Behind the object.
Horizontal lines remain Horizontal.
Vertical lines remain Vertical.
The Orthogonal lines formed from the corners diverge to the vanishing point.
One Point Perspective
Spectator
VP 4 VP 3 VP 2
VP 1 Horizon Line
PicturePlane
GroundLine
Parallel to
edge of
Object
Parallel to the
Inclined Line
Vanishing Points of Inclined Lines
Finding Auxiliary Vanishing Points
Horizon Line
Ground Line
Picture Plane
VP 1
VP 2
Leng
th
Leng
th
H
VP 3Specta
tor
H
Plan
Elevation
Height 2
VP 1
Picture Plane
Insert True Angle
Horizon Line
Ground Line
Hei
ght 1
Spectator
VP 2
Heig
ht
1
AVP
Insert True Angle
Height 2
AVP
Finding Auxiliary Vanishing Points
Picture Plane
Ground Line
VP 2
VP 2
VP 1
S
Aux VP 2
Aux VP 1
Height 2
H.L
Height 1
Height 1
Height 2
B
A
A
VP 1
B
Finding Auxiliary Vanishing Points
Curves & Circles in PerspectiveWhen circles and curves are drawn in plan, you may use a compass to ensure accuracy.
When drawn in perspective views, you must approximate circles and curved forms using reference points based on straight lines and
from angles that can be measured accurately.
Circles are the basis for a variety of more complex forms such as cones, cylinders
and spheres.
Being able to see these circles within these various forms as an indispensible aid
to reproducing them.
Picture Plane
Ground Line
VP 2VP 1
Horizon LineVP 2VP 1
Elevation
30°
S
Curves & CirclesIn Perspective