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alright, /3/, it's time for the test of your knowledge about 3DCG.
1: Are quads technically just two triangles?
If you answered 1 correctly
2: Why is it displayed the way it is, in 3D software?
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>>632548
>1: Are quads technically just two triangles?
Not until triangulation. Before that, they are stored as ordered sets of four vertices.

>2: Why is it displayed the way it is, in 3D software?
To make life (much) easier for the operator.
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>>632550
Why have heard so many times that quads are basically 2 triangles then? And if you deform them in the program, they will reveal 2 triangles they are made of.
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>>632573
matesss you bROKE the quiz
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>>632573
What is the correct answer? I want to know.
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>>632579
Meant for >>632574
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>>632580
I will answer some time later mateszz... this a weekly educational challenge for /3/!
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GPU draws everything as triangles.
so yeah, in the end one quad is two triangles with 2 of the shared vertices also share their normals.
3D software handles quads because it's easier to see flow of the geometry, it's possible to mirror a mesh and when you connect it to the counterpart, the sub-tris flow differently and your model is actually not symmetrical.
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guyz, I'm bak...

>>632600
>>632550
>>632573
You're correct, thankx for participating anons...
>Why have heard so many times that quads are basically 2 triangles then? And if you deform them in the program, they will reveal 2 triangles they are made of.
You're forgetting that the GPU is already drawing the mesh in your real-time viewport.

>1: Are quads technically just two triangles?
The GPU stores and operates on mesh data as triangles.
>2: Why is it displayed the way it is, in 3D software?
Badly done triangles are bad for deformation. Not showing these makes it easy to differentiate between user-created and GPU-created triangles.
>Why all triangles?
The GPU uses triangles simply because it's more efficient than going any higher. There is no hardware limitation- again, triangles are just faster to process and operate on. It could go lower than that, but it's the simplest polygon we can draw on.
More reading:
https://en.wikipedia.org/wiki/Polygon_triangulation
https://en.wikipedia.org/wiki/Tessellation_(computer_graphics)

thanks agin, will make a nu quiz next week in the same thread if it gets response! Else it's going to be a new thread! :D
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>Using quadriangle because it is ``better'' than triangle

If there is a single example of the foolishness and sheer arrogance of 3d artists, it is that. Video games developers use triangle every days to produce some of the finest 3d art ever created, but no, triangle aren't good enough for true ``artists'', they need some quadriangle or even fiveangle. Because more angles mean better art am I right?

Dumbass.
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>>633315
>quadriangles
Quadrangle, ya doof.
And jeez, you're really exposing your level of brainlet here. Like an above answer said, quads increase the visual quality of the mesh, making it easier to read as there's less information. In a 3dcg application, subdivisions work best on quads and not tris. To see it in action, subdivide a quadsphere and a regular UV sphere and see how on the latter, there's weird triangulation at the poles, while on the former it's a beautiful curved surface throughout.
And do you seriously think video game artists work with tris? They don't. Game engines break them up into tris because it's easier for the engine to work with.
It's not "artist skill" working with tris over quads, it's just being stupid.
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>>633315
Is this bait? There are already answers/posts above! Using tris is pretty un-maintainable, messes up deformation for animation(if done badly) and has symmetry issues(again, if done badly). Literally nobody works on tris(if that's what you're trying to say) specifically. Working in "quads" is still the best way to work. I've linked the two wikipedia articles in >>633292 already.
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>>632548
>>632573
"Basically 2 triangles" is an oversimplification.

1) They are stored as quads so the modeling software knows how to modify the faces when you do things like loop cuts or subdivision. For example, subdividing a quad has a noticeably different result than subdividing a triangle. They are all universally triangulated when it comes to viewing them though, including the viewport.

2) Triangles are always planar. If you plot 3 points in space they will always lie on a perfect plane, which is a crucial property to rasterization, and allows it to draw lines and shade between the points in a very straightforward manner regardless of its orientation. Nearly every 3D application uses a rectilinear perspective projection matrix which lets the rasterizer draw simple straight lines and pixels between the points and have it be coherent. (And before you ask about fisheye or barrel distortion, those are done first in rectilinear across different angles before being ray traced from the inside of a cube in a final pass.)

In fact, APIs like OpenGL, Vulkan, or DirectX only allow you to give it triangles. OpenGL used to be able to support quads, but it has been deprecated and no longer supported, because it just made the drivers do triangulation on the CPU anyway. Most game engines don't modify models so they don't need fancy quad or n-gon representations and just store everything as triangles to upload to the GPU. Most 3D software also use one of these APIs when rendering your model in the viewport. Even software renderers prefer triangles for the planar and linear properties listed earlier.
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>>633315
I agree that 3D fags are retarded when it comes to "muh quads" but quads subdivide differently than triangles and quads don't interrupt edge flow while modeling. In fact, if you're not retarded, you can use triangles to your advantage when subdividing.
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>>632548
The quad doesn't exist. It is but four vertices whose planar alignments are used warp and light bitmap snippets while the render pipeline is traversed.
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>>635631
>The quad doesn't exist.
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>>635628
Off topic: Why is literally everyone on this god forsaken planet obsessed with fisheye? Like, go ask a random person on the street about 3d, there's a good chance at some point they'll ask if it has anything to do with fisheye.
Just, why? Why is it so popular and why does every random associate it with 3dcg?
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>>635705
By fisheye, I get you mean the lens type, right? If so, I suppose it might have something to do with VR, since it's shot with those and has their characteristic look.
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>>635705
I'm sorry but I just literally have no idea what you're talking about. I have never seen this in my life ever.




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