topology tips


#1

Topology
When editing an organic model, especially one meant to be used in animation, it is important
to consider the topology of edgeloops. Edgeflow is a term used to describe how the edges of a
mesh should follow the form of the shape, and how they should be positioned along folds so
that bending doesn’t crease the faces. Topology describes the effectiveness of the edgeflow of
the lines of a mesh, which can be good or bad depending on the following factors:
• How well the lines follow the form of the shape. Often, smoothing a model with
multiresolution or subsurface modifiers will distort the overall shape if the topology is
bad. Edges should be evenly distributed, and extra edges should be positioned at sharp
corners.
• Whether the faces are quads (four sided), or triangles and N-gons (an N-gon has five or
more edges). In most cases, especially when a mesh is designed to bend like flesh, quads
are considered better because they twist easily (as opposed to triangles, which don’t
twist well, and N-gons, which often have so many vertices that they can warp into odd,
unwanted shapes).
• Whether the lines available allow easy distortions for animation (i.e., there shouldn’t be
too many lines, they should be evenly spaced, and they should follow the direction of
curves).
For shapes like the head, it is good edgeflow to have concentric circles around cavities like
the mouth and eyes (see Figure 3–18). This allows for a lot of flexibility in terms of easy
reshaping, opening, closing, and so on. For limbs that bend, such as elbows and finger joints, it
is good practice to have three edgeloops or more around each bend in order to enable the mesh
geometry to bend in a smooth curve. Poorly aligned edgeloops can make the desired surface
deformations more difficult to create (e.g., imagine folding a piece of paper in half, and then
unfolding it and trying to crease it along an imaginary line 10 degrees off from your crease).


#2

I’m not sure why you posted this as it’s the kind of thing we see in modelling for beginners books.


#3

I thought it would help others


#4

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