Maya modeling: Modeling the torso
We continue to build our character by fleshing out the torso.
In the last tutorial, we blocked out the major forms for a human figure. In this tutorial, we will continue from where we left off by building up the torso.
To work on just the torso, without affecting the rest of the geometry, we will extract the faces of the torso from the mesh and hide the remainder. At this stage, we will be laying out all the major edge loops that will give us the best results should the character be deformed later on. We will be forming our topology to match the muscle flow and skin flow of a human, but also thinking about when it's not politic to follow anatomy so strictly.
Step 1: Extracting the torso
Download the scene files from here and then open up scene file '01_start', or open up your own scene file. With the mesh selected, go into Face mode and start selecting all the faces of the chest, back, shoulders and pelvis. Check that you are happy with the selection from all camera angles and then go to Mesh > Extract.
Next, select all the geometry in the scene and go to Edit > Delete By Type > History. This is to break the connections between the extracted geometry and the original geometry.
Step 2: Defining the major muscle groups and skeletal landmarks
Before we start defining the muscle groups, we need to instance our geometry so we can work with a complete mesh. Select the torso geometry, make sure the pivot is at the center of the World space (hit Insert on the keyboard and use grid snapping if not) and go Edit > Duplicate Special (Options). Change the Geometry Type to Instance and pop a -1 into the first Scale box and hit Apply.
Now, using the Split Polygon tool, start cutting into the model, defining the flow of the pectoralis major, the deltoids and the rectus abdominal muscles. Also define the skeletal landmarks: the clavicle and the scapula. This is the time to experiment with the edge flow as the geometry is at its lowest subdivision. Once we start adding further detail, re-working the topology can be tiresome.
Step 3: Building up the forms
Once the major edge flow lines have been determined, start to build them up and add more volume and form. Going through one region at a time, start following the directions of the muscle fibers, considering where the muscles originate and where they insert. Do not go overboard in increasing the resolution; at this stage, we do not want a mesh that is too dense to edit easily later on. Make sure that each edge loop added or extrusion performed gets pushed and pulled to its fullest. If and when you cannot refine the shape with the detail you have, add more.
Step 4: To follow or not follow anatomy
If the mesh is to deform for animation, then it is vital that the edge loops support this. Through trial and error, you'll find that the more you model and the more you deform your characters, you'll get a bearing of when to and when not to follow anatomy.
In the torso, we'll loosely follow the muscle structure of the external obliques. On the human form, these muscles come down at a 45 degree angle from ribs 5 to 12. If we were to mimic this behavior, we would have issues if the character was to twist. To combat this, we'll stick to a more grid-like approach around the region.
Step 5: Tidying up
Before calling it a day with the torso, go through and make the following checks. First, check that everything is in quads. I use the Mesh > Cleanup tool to aid me in this.
Set the Operation to Select matching polygons and Fix by Tesselation to 4-sided faces. This will select all the quads. I then go to Edit > Invert Selection to select all the triangles and n-gons. Once I know where they are, it's a case of going in and reworking that section.
Next, I'll even out all the faces so they are more square-like than rectangular. If I need to add a couple of extra edge loops here and there, then I will. Using the Mesh > Sculpt Geometry tool with the Operation set to Relax is a great way of evening out the edges.
We'll leave the torso here for now, but we'll come back to it for further refinement once the other forms have been built up.
Top tip 1: Figure out topology beforehand
Before I begin adding edge loops and performing extrusions here and there in Maya, I like to spend some time drafting how I think the topology should be laid out. Taking my reference into Photoshop, or, my personal favorite drawing app at the moment, ArtRage, I can quickly figure out where the key edge loops should go. I don't go into too much detail as I still want some freedom in Maya to experiment, but minutes spent here can save you hours later on.
Top tip 2: Sculpt out the forms
Moving points around in Maya can be time-consuming. As a result I like to import my model into a package such as ZBrush or Mudbox to make full use of the sculpting tools available. I then export the model back into Maya to continue refining the topology.
Click HERE to see the previous tutorial in this series.
Want to start from the beginning? Click HERE to see the first tutorial in this series.