Retopology

Retopology is a process that allows high poly models to be used in games by creating optimal geometry so that the game will run more smoothly, it will also allow you to make models suitable for being animated. To begin the retopology process, a base mesh is required. You can either choose one from the Zbrush directory or model your own. For this lesson I decided to build on top of a base Z brush mesh.

Projection-

Using out original model to bring details back into our new retopologies .mesh

Maya Quad draw -

With your base mesh made in Z brush, you will need to shrink down the size of the model so that you will be able to bring it into Maya. To do this we will need to decimate our model [if you are making something organic you can just go straight into decimating however if you are working with hard surfaces you will need to Z remesh it first.]. Under the Z-plugin tab, fin the decimation master and select pre process current [pre process all if there's more than one subtool]. Doing this this drops down total polycount of the model and makes it more manageable to use. In the subtool menu, find export  and then export as an fbx. You will need to select "selected" option or "all" depending on how many subtools are in your project, then select export as fbx 2020, and export as bin [binary files]. Finally we will need to click Maya Y up [if you are using blender use Maya z up] and then press ok. We can now minimize Z brush.

                                                 

In Maya, find the import option under the File tab and find where your file is saved to import it. Once you bring it into Maya, it might be quite small or large to begin with, to fix this issue simply scale to size. Now go to the top bar above the workspace and set live surface option, this is the icon with the plain magnet. You can assign a new material to it if you dont like the default one.

Now, turn the symmetry [world x] on and select the quad draw tool, map out forehead to begin with. We will then need to move onto the "mask" formation around the eyes, make concentric circles and try to make things radiate out from there. You can do this by placing points on the head [it should be mirrored on the other side so you only have to worry about one side]. Some other keybinds to keep in mind are:

tab key - extrude edges of quad

shift lmb = relax rough topology

ctrl lmb - add edge loop

ctrl shift lmb - delete components

lmb drag - auto weld vertices

Here is the retopology i did on my dog head.

Retopology in Zbrush-

Back in Z brush select your work and then in the brush menu select the z remesher guide, we will need to draw in some guides with the guide brush, draw in where the curves should be [around the eyes, mouth, nose], this will tell the Z remesher where the curves are. Once you have put everything in, select Z remesh which will retopologize it for you.