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 mazm12-11-2006, 09:34 PMHi guys :) I saw this word "quad" many times but really i don't know what is quad meaning ? can anyone explain this to me. thanx
12-11-2006, 09:46 PM
I think the meaning of "quad" in 3d is a polygon with four edges. The 3d models are made by polygons or faces.

newellteapot
12-12-2006, 08:56 AM
Hi!
A quad, short for quadrilateral, is a polygon with four sides (in graphics, the edges) and four vertices.
;)

mazm
12-12-2006, 12:37 PM

blackwood
12-12-2006, 05:00 PM
I don't wish to sound pedantic, but at this point anyone else reading this may still be confused. So...

Polygons or ngons are faces with 4 or more sides.
Quads are faces with 4 sides.
Trianges or tri's are 3 sided faces.

Everything is made up of tri's and the process where quads and other polys get converted into trianges is triangulation. So why make things in quads? Its easiser to work with and important for smoothing operations.

newellteapot
12-12-2006, 05:29 PM
Not pedantic at all, it's clear, useful and complete, thank you for posting:)

I don't wish to sound pedantic, but at this point anyone else reading this may still be confused. So...

Polygons or ngons are faces with 4 or more sides.
Quads are faces with 4 sides.
Trianges or tri's are 3 sided faces.

Everything is made up of tri's and the process where quads and other polys get converted into trianges is triangulation. So why make things in quads? Its easiser to work with and important for smoothing operations.

mazm
12-13-2006, 12:11 PM
blackwood :thumbsup: it's always better to add more details in any question in this forum.

thanx

meatycheesyboy
12-16-2006, 11:43 PM
I don't wish to sound pedantic, but at this point anyone else reading this may still be confused. So...

Polygons or ngons are faces with 4 or more sides.
Quads are faces with 4 sides.
Trianges or tri's are 3 sided faces.

Everything is made up of tri's and the process where quads and other polys get converted into trianges is triangulation. So why make things in quads? Its easiser to work with and important for smoothing operations.

This probably is pedantic but I slightly disagree.

A polygon or an ngon can have any number of edges including 3 or 4. A quad has 4 sides but is also a polygon and is also an ngon; the same holds true for a tri; a tri has 3 sides but is also an ngon or a polygon.

Its like how a square is a rectangle but a rectangle is not a square.

lucavfx
12-18-2006, 10:47 AM
This probably is pedantic but I slightly disagree.

A polygon or an ngon can have any number of edges including 3 or 4. A quad has 4 sides but is also a polygon and is also an ngon; the same holds true for a tri; a tri has 3 sides but is also an ngon or a polygon.

Its like how a square is a rectangle but a rectangle is not a square.

from wikipedia...

A polygon is a closed planar path composed of a finite number of sequential line segments (commonly called edges).
Polygons are named according to the number of sides, combining a greek-derived numerical prefix with the suffix -gon.
The triangle. quadrilateral and nonagon are exceptions.
For larger numbers, some mathematicians use the numeral itself (6-gon).
A variable can even be used, usually n-gon.

Polygon names Name Edges
henagon (or monogon) 1
digon 2
triangle (or trigon) 3
pentagon 5
hexagon 6
heptagon (avoid "septagon" = Latin [sept-] + Greek) 7
octagon 8
enneagon (or nonagon) 9
decagon 10
hendecagon (avoid "undecagon" = Latin [un-] + Greek) 11
dodecagon (avoid "duodecagon" = Latin [duo-] + Greek) 12
tridecagon or triskaidecagon (MathWorld) 13
pentadecagon (or quindecagon) or pentakaidecagon 15
icosagon 20
icosihenagon 21
triacontagon 30
tetracontagon 40
pentacontagon 50
hexacontagon (MathWorld) 60
heptacontagon 70
octacontagon 80
enneacontagon 90
hectagon (also hectogon) (avoid "centagon" = Latin [cent-] + Greek) 100
chiliagon 1000
myriagon 10,000
decemyriagon 100,000
hecatommyriagon (or hekatommyriagon) 1,000,000

So to wrap it up

n-gons 1 or more edges
polygons 1 or more edges
triangles 3 edges

Hope it helps :)
Luca

Shonner
12-19-2006, 04:09 AM
Quad is a nickname for a 4-sided polygon.

newellteapot
12-19-2006, 08:48 AM
This post by Lucavfx should be a sticky! :)

from wikipedia...

A polygon is a closed planar path composed of a finite number of sequential line segments (commonly called edges).
Polygons are named according to the number of sides, combining a greek-derived numerical prefix with the suffix -gon.
The triangle. quadrilateral and nonagon are exceptions.
For larger numbers, some mathematicians use the numeral itself (6-gon).
A variable can even be used, usually n-gon.

Polygon names Name Edges
henagon (or monogon) 1
digon 2
triangle (or trigon) 3
pentagon 5
hexagon 6
heptagon (avoid "septagon" = Latin [sept-] + Greek) 7
octagon 8
enneagon (or nonagon) 9
decagon 10
hendecagon (avoid "undecagon" = Latin [un-] + Greek) 11
dodecagon (avoid "duodecagon" = Latin [duo-] + Greek) 12
tridecagon or triskaidecagon (MathWorld) 13
pentadecagon (or quindecagon) or pentakaidecagon 15
icosagon 20
icosihenagon 21
triacontagon 30
tetracontagon 40
pentacontagon 50
hexacontagon (MathWorld) 60
heptacontagon 70
octacontagon 80
enneacontagon 90
hectagon (also hectogon) (avoid "centagon" = Latin [cent-] + Greek) 100
chiliagon 1000
myriagon 10,000
decemyriagon 100,000
hecatommyriagon (or hekatommyriagon) 1,000,000

So to wrap it up

n-gons 1 or more edges
polygons 1 or more edges
triangles 3 edges

Hope it helps :)
Luca

12-19-2006, 06:01 PM
hahah luca, that should come with a pronounciation guide. Sweet find.

Snikske
12-26-2006, 04:36 PM
a quad isn't always planar i think. Only tri's are always planar.
A quad consist of two tri's, with one hidden edge.

kirigoi
01-04-2007, 12:17 PM
Right you are Snikshe, you can fix rendering errors from non-planar quads by converting them to tris; tris by definition are always planar.

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