Base Mesh Camp for ZBrush 4

Base Mesh Camp for ZBrush 4

Topology matters.

When building 3d models I’ve seen time and time again that topology can affect how a model bends, how it looks in certain lighting and even how well it can be morphed. When sculpting a poorly topologized base mesh in ZBrush, I have found myself fighting against the tendencies of the underlying shape. It wants to fold where I want it to expand. Triangles in the wrong spots can cause unsightly bumps when subdivided again making sculpting difficult.

Experience has taught me that correcting bad topology can often take longer than simply building the right topology in the first place. Having a good base mesh increases artistic productivity by reducing the time it takes to build a figure completely from scratch. Creating your own base mesh also helps you to create more original figures for your portfolio.

I generally create my base meshes in Silo and then sculpt then in ZBrush. Although these guidelines are based upon my workflow they could easily be applied to Blender, Maya or any other tool that allows for sculpting and edge loop creation.

Here are some guidelines for making the topology of human base meshes that I have found useful along with practical examples:

1) Use quads over most of the figure.

Programs like Blender, Silo and ZBrush give the artist the power to increase detail in a model through subdivision. As I’ve mentioned in previous posts, subdivision works best with quads (4 sided shapes). Some triangles in hidden areas (e.g. nostrils) are fine since they won’t be seen. As much as possible avoid using triangles.

2) For a base mesh, use the least number of quads possible.

With subdivision, less is more. It is easy to put too much detail into a base mesh and end up with a figure that is too specific and not general enough to be molded into the desired character. Try to keep features vague so they can easily be manipulated later. With vague details you can make dramatic changes in your figure at a low subdivision level and project the results on a high level.

Always try to reduce the number of quads you put into your base mesh. Try viewing your mesh with subdivision with some edge loops removed. If the effect is undesirable don’t forget CTRL-Z or CMD-Z.

3) Use larger quads on the body and smaller quads on the face.

Generally, more detail is required for the face than the figure especially for complex features like the ears and the nose. Having more geometry to work with makes it easier to form the desired figure and reduces texture stretching when the figure is painted.

4) Mimic the underlying musculature and skeleton of the figure in the placement of quads.

When quads mimic the underlying structure it becomes much easier to create realism in the final figure. You won’t have to fight the mesh to emphasize structures in your model. A good base mesh will help you sculpt. Visual reference is especially useful for this purpose. One source for visual reference that every 3D artist should know about is

Placing quads to match important landmarks on the body (e.g. eyes, nose, lips, collar bones, hips) makes the sculpt easier. The base mesh reminds the sculptor “this is where to place a feature”. It also helps to maintain the form as it is sculpted.

5) Be prepared to star over.

In writing this article, I created a base mesh I was reasonably happy with and found myself becoming unhappy as I sculpted on it. I had to go back to the drawing board and change some edge loops. The newer mesh sculpted better but this is an iterative process. I will update the mesh as my skill level increases. Improvement always requires refinement.

For more information, visit these sites:

Zbrush Heads

In recent months I’ve been making an effort to improve my sculpting skills in Zbrush. Heare are some heads I made with ZBrush based upon the great teaching of Ryan Kingslien at ZbrushWorkshops. I plan to retoplogize these heads and use them with full figures.

Turntable Face 1 on YouTube

Turntable Face 2 on YouTube

Turntable of Face 3 on YouTube

ZBrush 4R2 – DynaMesh: Bye bye manual retopology?

Update Jan 29, 2013: Even with ZBrush 4 Release 5,  QRemesher and the topology brush, the dream of never having to do manual retopology is just that a dream. Manual still gives the best results, although I am sure Pixologic will improve their algorithms. The title of the article is a bit misleading but I keep it for historical purposes.

Update Oct 8, 2011: Free ZBrush 4 Release 2 Tutorials from Pixologic

DynaMesh is a new feature of ZBrush 4 release 2 that allows the user to add to a mesh while at the same time maintaining an evenly distributed topology! What is even better about DynaMesh is that the new topology is mostly made of quads, making it easier to sculpt in ZBrush and animate in other 3D apps. I am not certain but I suspect this instant retopology technology was borrowed from Sculptris after it was acquired by Pixologic. The main difference between Sculptris and ZBrush with instant retopology is that Sculptris only uses triangles whereas ZBrush uses mostly quads. While DynaMesh reduces the work required for retopology it is not perfect. Stray triangles may appear in the retopologized surface that will need to be edited out manually.

To make use of DynaMesh, here are the steps.

1) Drop your Ztool onto the canvas
2) Enter edit mode (press ‘T’)
3) Make the tool Polymesh3D
4) Open the Geometry palette
5) Click on the ‘DynaMesh’ button

Once DynaMesh is enabled, ZBrush can automatically retopologize your mesh every time you hold down the control key while clicking and dragging on the canvas. Simply clicking and dragging turns sculpted features into a more uniform mesh and maintains quads for most of the new retopologized mesh. This is useful for fixing topology after stretching a model with the Morph Elastic Brush or the Snake Hook Brush.

Dynamesh really shines when retopologizing after inserting a mesh. ZBrush 4 Realase 2 has added a number of “Insertion Brushes” which allow the artist to add meshes to the current mesh. In my example I inserted a nose on a sphere. Control clicking and dragging will combine the old mesh with the inserted mesh. The combined mesh will again be composed mostly of quads with no breaks between the previously separate meshes. To prevent two meshes from being combined, remember to use Group split before remeshing to turn them into separate subtools.

You can also control the resolution of your retoplogized mesh with the slider underneath the DynaMesh button. Increasing the slider before remeshing creates a finer mesh. Decreasing the slider before remeshing creates a coarser mesh.

Below is my DynaMesh example sped up 5 times.