What is topology?

[BrandonD]

The shape of a surface is topology. For example, a Grid with an animated Noise Modifier has "changing topology."

[Reality3D]

From this image above i would say: They have the same shape, but different Topology !

[BrandonD]

True, though I was trying to give a very simplistic explanation. So I guess I should rephrase it more as "the definition of a shape is topology." How a shape is defined.

In medical terms topology is defined as "The anatomical structure of a specific area or part of the body. "

In mathematics it's "The study of the properties of geometric figures or solids that are not changed by homeomorphisms, such as stretching or bending. Donuts and picture frames are topologically equivalent, for example"

[Animare]

thanks guys, thats a good explanation, so what is considered as good topology and bad topology when it comes to modelling?

[Reality3D]

In organic modelling good topology usually means that edges of the mesh flow in the direction of the muscles. Sorry about my nasty english :)

[3dsmax5]

You should avoid modeling with triangle faces, only quad polys!
:wip: :D :beer:

[googlo]

Here's 3dsmax' definition of topology:

Topology
When objects and shapes are created, each vertex and/or face is assigned a number. These numbers are used internally to determine which vertices or faces are selected at any given time. This numerical arrangement is called topology.

When you select vertices or faces and apply a modifier to the selection, the modifier stack keeps track of which faces/vertices the modifier affects. If you later return to the selection level of the stack and change the selection, you change the topology to which the modifier is applied.

The term topology refers to the structure of faces and vertices as well as their numbers. For example, by carefully setting various parameters, you could make a box and a cylinder with the same number of vertices. You might then think you could use the box as a morph target for the cylinder. However, because the two objects are created with such different methods, the vertex numbers on these objects would be ordered very differently. Morphing causes each numbered vertex to go to its corresponding place on the morph target. In a case such as this, with two objects with such different topology, morphing from one to the other would cause the object to crumple or turn inside out as it morphs.

[sam]

good topology means different things when modeling in low poly than it does in mid or high poly

in low poly situation, you actually do model in tris and try to keep the overall look as close to a geodesic ideal as possible (meaning as close to equilateral triangles as possible). So in low poly a geodesic topology is preferred as the most efficient at maintaining texture space and mesh volume and low vertex count.

in high to mid poly situation, many people have found that modeling in quads and keeping track of the flow of edge loops and edge rings is the way to go as far as defining good topology. Putting edgeloops at key places, such as around the bowls of the eyes helps manage the creation, refinement, and animation of the mesh. So in mid to high poly, some might talk of good topology as defined by nicely placed edge loops.

i hope this helps

[Animare]

Thanks a bunch guys, I had a really good read, and got a few insights to it, so its getting there, appreciate it, it really helps. I'm scared to ask "What are edge loops now"... will do a bit more reading on it and come back here for some tips/feedback on it.

Thanks again

:beer:

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