3a. orthographic projection - multiview projection

8/16/2019 3a. Orthographic Projection - Multiview Projection

1/31

Chapter 3Orthographic

Projection


2/31

TOPICS

Object representation

Glass box concept

Line convention

Orthographic projection of point,

line, plane, surface and object.

Multiview projection


3/31

OBJECT REPRESENTATION

Axonometric projection

Multiie! projection


4/31

M"#TI$IE% PROJECTION

Three principle &imen'ion'o( an o)ject *

Width Depth

Height

Width

H e i g h t

Depth

D e p t

h

* can )e pre'ente& onl+t!o in each ie!,

A&jacent ie!-'.

i' nee&e& to(ul(ill the 'i/e

&e'cription,


5/31

0, Reole the o)ject !ith re'pect

to o)'erer ,

TO OBTAIN M"#TI$IE%

REPRESENTATION O1 AN OBJECT

2, The o)'erer moe aroun& the

o)ject,


6/31

RE$O#$E TE OBJECT

1rontie!

Right 'i&e ie!

Top ie!


7/31

OBSER$ER MO$E ARO"N4

1ront

ie! Right 'i&eie!

Top ie!


8/31

TE 5#ASS BO6 CONCEPT

Bottom ie!

#e(t 'i&e ie!

Rear ie!


9/31

eight%i&th

4

e p t h

i'tor+


10/31

Orthographic

Projectiono( O)ject 1eature'


11/31

OBJECT 1EAT"RES

E&ge' are lines that represent the boundar

between two faces.

Corner' !epresent the intersection of two or

"ore edges.E&ge

Corner

E&ge No e&ge

No corner No corner


12/31

Sur(ace' are areas that are bounded b edges

or li"iting ele"ent.

#imiting

element

is a line that represents the last visible

part of the curve surface.Sur(ace Sur(ace Sur(ace

#imit #imit

OBJECT 1EAT"RES


13/31

#

$

PROJECTION O1 POINT-S.

#%$!

#&

$% #!

$&

#% #!

#&

$% $!

$&

E7ual

&i'tance


14/31

#

$

#% $% $! #!

#&

$&

$!

#! #% $%

#&

$&

True length

NORMA# #INE

True lengthPoint

E7ual

length

PROJECTION O1 #INE


15/31

#$

#% $% $! #!

#&

$&

INC#INE4 #INE1ore'hortene&

$!

#!

#%$%

1ore'hortene&

#&

$&

True length

#

E7ual

length

PROJECTION O1 #INE


16/31

#$

#%

$% $!

#!

#&

$&

OB#I8"E4 #INE

#

E7ual

length

$

1ore'hortene&1ore'hortene&

1ore'hortene&

$!

#!

#%

$%

#&

$&

PROJECTION O1 #INE


17/31

$'

#

PROJECTION O1 P#ANE

$% #%,'% '! #!,$!

#&

'&

NORMA# P#ANE

E7ual

length

E&geE&ge

True 'i/e

'!

#!,$! #%,'%

$%

#&

$&

'&

$&


18/31

$'

$% #%

'!

#!,$!

#&

'&

INC#INE4 P#ANE

#

E7ual

length$&

'

'%

E&ge

'!

#!,$!

1ore'hortene&

$&

'&

#&

#%

'%

1ore'hortene&

$%

PROJECTION O1 P#ANE


19/31

$'

$%

#%

'!

#!

#&

'&

OB#I8"E4 P#ANE

#

E7ual

length$&

'

'%

$

$!

1ore'hortene&

'!

#!

$!

#%

$% '%

1ore'hortene&

#&

$&

'&

1ore'hortene&

PROJECTION O1 P#ANE


20/31

PROJECTION O1 OBJECT

&he views are obtained b projecting all object

features to the picture plane.

9ou hae to project the remaining 'ur(ace' !hich are

ini'i)le too :

9ou hae to project the remaining 'ur(ace' !hich are

ini'i)le too :


21/31

'

'

'



22/31



23/31

#ine Conention


24/31

#INE CON$ENTION

(recedence of coincide lines.

Hidden line drawing.

'enter line drawing.


25/31

PRECE4ENCE O1 #INE

$i'i)leline$i'i)lelineOr&er o( importance i&&enlinei&&enline Center lineCenter line


26/31

I44EN #INE PRACTICE

Hidden line should join a visible line, except it

extended fro" the visible line.

Correct

No :

)oin

Leave

space


27/31

Correct No :

Hidden line should join a visible line, except it

extended fro" the visible line.

Leave

spaceLeave

space

I44EN #INE PRACTICE


28/31

Hidden line should intersect to for" # and T

corners.

Correct

No :

# T

I44EN #INE PRACTICE


29/31

Hidden arcs should start on a center line.

I44EN #INE PRACTICE


30/31

CENTER #INE PRACTICE*n circular view, short dash should cross at the

intersections of center line.

%or s"all hole, center line is presented as thin

continuous line.

'enter line should not extend between views.

#eae 'pace #eae 'pace


31/31

Leave the gap when centerline for"s a

continuation with a visible or hidden line

#eae

'pace#eae

'pace#eae

'pace

#eae

'pace

'enter line should alwas start and end with

long dash.

CENTER #INE PRACTICE

3a. orthographic projection - multiview projection

Documents