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Prospective Drawing

Type of drawing that more closely resembles

the way we see things in the real world.

This is a technical drawing which is ones own

interpretation of what one sees.

A perspective projection is pretty much what

we interpret as 3D.

When drawing in perspective, we can vary ourpoint of view. This is not true in either isometric

or oblique drawings , both of which have a

fixed point of view and appearance.
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Changing the location of the vanishing pointwill cause a change in the appearance of theperspective drawing.

The advantage of perspective drawing is that itmakes objects appear more realistic

The first requirement when setting up aperspective view of an object is to obtain

accurate information. This information is generally in the form of

plan, elevation, and sections. These comesunder orthographic projection.


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Orthographic Projection

Orthographic projection is a way of drawingan 3D object from different directions. Usually

a front, side and plan view are drawn so that a

person looking at the drawing can see all theimportant sides.

Orthographic projection is a means of

representing a three-dimensional object in twodimensions, by means of related views.


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Orthographic Projection When the projection

is made by firstdrawing the plan, thenthe front view(elevation)immediately above

and the side view(end elevation) besidethe front elevation.

Used in Europe.

In this the plan is

immediately abovethe elevation of thefront face of theobject. And the end

elevation is placednext to the frontelevation.

Used by Americans.

First angle projection Third angle projection


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Station Point

This is the chosen point from which the object

is to be viewed.

Also known as observer, viewing point or

eye position.


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Center Line Of Vision

Also known as the direct line of vision or

direct line of sight.

It is a line from the station point to the center of

interest of the object.

This line is always represented as vertical linein perspective drawing


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Cone Of Vision

The normal maximum range within which it is

possible to see clearly and easily is known as

cone of vision.

The cone of vision is accepted as being acone of less than 90 and is seldom if ever

shown as more then 60.

For the purpose of perspective drawing it isusually limited to 60 or less.


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Picture Plane

This is an imaginary vertical plane on which

the perspective drawing is supposed to be

done.


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In perspective drawing the picture plane is an imaginary

plane, normally at 90 to the ground plane.

It can be placed in front of, behind of, even through the


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THE EFFECT OF MOVING PICTURE PLANE


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Vanishing Point

Any two or more

parallel lines will, if

extended indefinitely,

appear to convergeat a point. This point

is known as

vanishing point.

In perspectivedrawing it is

necessary to locate

exactly the vanishing

points for parallel


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VAINISHING POINT IN A RECTENGULAR OBJECT


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Height Lines

Line used for measuring all vertical heights.


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Horizon Line

It is the line produced on picture plane by the

intersection of the horizontal plane through the

eye level of the spectator.


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Ground Line

Intersection of ground plane and picture plane.


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DRAWING THE

PERSPECTIVETwo point perspective


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STEP 1- OBTAIN INFORMATION


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STEP 2- LOCATE THE STATION POINT AND THE DIRECTION

OF VIEW


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STEP 3- CENTER LINE OF VISION TO BE VERTICAL..


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STEP 4- CHECK THE LOCATION OF THE STATION POINT

WITH THE CONE OF VISION


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STEP 5- LOCATE THE PICTURE PLANE AT 90 TO CENTERLINE OF VISION.


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STEP 6- LOCATE VANISHING POINTS


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STEP 7- LOCATE THE HEIGHT LINE


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STEP 8- LOCATE THE HORIZON LINE AND PROJECT UP TOLOCATE VANISHIVG POINT.


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STEP 9- LOCATE THE GROUND LINE


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STEP 10- LOCATE HEIGHT OF OBJECT ON THE HEIGHTLINE AND TOP AND BOTTOM LINES OF SIDE A-B IN

PERSPECTIVE VIEW


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STEP 11- VISUAL RAYS USED TO LOCATE POINTS A ANDB IN PERSPECTIVE VIEW OF THE OBJECT.


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STEP 12- VISUAL RAYS AND PERSPECTIVE LINES TOCOMPLETE THE PERSPECTIVE VIEW OF THE OBJECT.

ONE POINT PERSPECTIVE


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ONE POINT PERSPECTIVE

DRAWING

Perspective drawing can use one, two or three

vanishing points. One-point perspective isoften used for room interiors. Two-point

perspective has many applications fordeveloping ideas in 3D. Three-pointperspective is often used for drawings of tallbuildings.


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projection: a representation of a three-dimensional solid on a two-dimensional

surface

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