IMPROVE YOUR PORTRAITS WITH REALISTIC HAIR
Fábio M Silva shows how to perfect your portraits using Zbrush, 3ds Max and the Hair Farm plug-in
Fábio M Silva reveals his process for creating realistic hair and eyebrows using Zbrush, 3ds Max and the Hair Farm plug-in
AUTHOR
Today we will be creating eyebrows to ensure your portraits look more realistic. Just like hair and eyelashes, eyebrows are often neglected in tutorials about creating the human body in 3D, but unrealistic-looking eyebrows can really make the difference between a believable and an unbelievable 3D model.
First, we will take our model into Zbrush and mask the areas we need to use as our scalp or hair emitter. Zbrush is great for doing this since we can basically paint in 3D on our high resolution model in order to make it look exactly the way we want it. Then, we will perform quick actions such as generating UVS and retopologising automatically to get clean and fast results.
This technique – which uses Zbrush, 3ds Max, the Hair Farm plug-in and Photoshop to make eyebrows – can also be used to create other types of hair.
01 LOADING THE MODEL
Load your Zbrush model. If you didn’t make it in Zbrush, insert a Polymesh3d object and then use the import function. Export your model from your 3D package to .obj or another format that Zbrush supports. Once your model is loaded, make a duplicate of it. We’ll use this as a backup.
02 TESTING THE MESH
Paint a test mask onto the surface to check if it has enough subdivisions to ensure a clean and detailed mask. If your mask is low resolution or jagged, increase the subdivision until you get a clean result. It doesn’t really matter if you go a bit overboard (as long as it doesn’t slow down your machine) as we are only interested in getting masks to generate objects and we won’t overwrite the original object.
03 ACTIVATING SYMMETRY
Go to the Transform menu, enable Activate Symmetry and make sure X is enabled.
04 PAINTING THE BROWS MASK
Start painting the mask for the eyebrows. Use reference to ensure you get a proper shape. Use Ctrl+alt to erase any unwanted areas and Ctrl to add more surface to the eyebrow. Review the brows from all angles until you’re satisfied.
05 TURNING THE MASK INTO A POLYGROUP
Go to the Tool menu. Open the polygroup tab, and click Group Masked. This will turn our selection into a polygroup for easier access, and also means it can be isolated from the rest of the geometry.
06 ISOLATING THE SELECTION
Hold Ctrl+shift, then click in the masked area of the eyebrows to isolate the selection. Go to the Tool menu, open the Geometry tab, and under subdivision levels, delete both Lower and Higher subdivisions if you have either of them.
07 DELETING THE HIDDEN MESH Go to Tool>geometry, select Modify topology, then press the Delete Hidden button. This will delete all the polygons that are not visible at the moment. 08 AUTO-RETOPOLOGIZING THE BROWS Go to Tool>geometry, and open the Zremesher tab. Click the Zremesh button. This tool is amazing, as it usually creates great topology instantly. A few years back, you would need to remodel all these polygons by hand, something which, depending on the complexity of the object, could take hours. Now, with a simple click and a few seconds… voila! It does a really good job most of the time.
Tweak the values of the polycount slider and feel free to press Half to turn it on. Click Zremesher a few more times until you get a good-looking brow mesh that is not too high res (but not too low res either). Make sure you have enough polys not to sacrifice the overall outline we had with the brows. 09 SETTING UP THE UVS USING UV MASTER Go to the Zplugin menu. Open the UV Master rollout and press Unwrap. This will lay out the UVS nicely for your mesh, enabling us to paint a mask for the brows in Photoshop later on. You can double check how they look by pressing Flatten. While in this mode, you can modify the UV’S position and scale. Press Unflatten to return to the geometry. 10 EXPORTING THE BROWS MESH AS .OBJ In the Tool menu, scroll down to the Export section. Disable the Grp button and leave everything else at default (see image 10 to compare my export settings with yours). Scroll back up, and press Export. Save as a .obj file. Alternatively, you can use GOZ to transfer your work into a compatible application. 11 START 3DS MAX
Open 3ds Max, go to the Import menu, and import the .obj (if you used GOZ it should appear in the scene automatically). Make sure you also import the original head so we can have an idea of how the brows will look on the model.
Select the brows mesh we imported, go to the modifier menu, and select Hairmesh edit. Choose Polygon Selection mode and make sure the brows are selected completely. Click on Extrude and extrude slightly to represent our hair volume (in this case, the eyebrow hairs’ length). Once you’ve done this, adjust the verts until you have something that looks more like an eyebrow from the top. 12 ADJUST GEOMETRY
Adjust geometry at the vert level from all views. Make sure you look at real life references, if possible, and your own photos. Don’t forget male and female eyebrows are very different.
13 GENERATE HAIR
Load a Hair Generate modifier and set the hair count to 5,000, Length to 28.6 and Thickness Curve to 0.01. Play with the viewport percentage until you get something that is workable in the viewport.
14 TWEAK THE HAIR
Press M on the keyboard to go to the Material Editor. Add a Hair Simple material to the editor slot and apply it to the eyebrow mesh under the Hair Generate modifier in the Material section. Tweak the hair count to a higher value (15,000) and set the length to 100. Darken the diffuse colour of the Hair Simple material to make the brows darker. Tweak the eyebrow shape a bit more as you work.
15 ADDING A LIGHT
Go to Light tab and select Target Spot; add it to the scene and aim the target at the face. Move the light up. Change the shadow type to Hair Shadow Map.
16 FIXING THE PIVOT
Select the brow mesh, go to the Hierarchy tab, and select the option Affect pivot only. Move the pivot up (it should be at 0,0,0 in the scene) and place it in the eyebrow, where it will help you move the eyebrow mesh onto the head mesh.
17 TWEAKING THE SHAPE
On the modifier list from the brow mesh, go to Editable Poly and change the shape of the original mesh to conform better to the head. When the warning appears about the modifier in the stack being dependent on topology, simply press Yes. As long as no verts or edges are added we should be fine. Remember to use soft selection to move several verts at once. Once you are happy with your eyebrows, do a test render. Continue to tweak the
shape, and extrude once more to get a bit more depth and more control over the curvature of the eyebrow (curvature if viewed from above).
18 Adding hair to Poly Modifier
Go to the Modifier list and add a Hair to Poly. This will convert the brows to a mesh. Then go to the Hair Generate modifier and tweak the thickness.
19 Adding More hair Style Modifiers
Add Hairstyle Wisps. This will generate more strands of hair. Tweak the count until you have something desirable. In my case, a count of 3 seemed to work well. Since we have a lot more hairs, this is a good time to refine the eyebrow shape.
20 ADD A uv Modifier
Add an Unwrapuvw modifier. Open the UVW Editor. Now go to Tools>render UVW Template. Save the image somewhere on your drive.
21 Paint in Photoshop
Open Photoshop and the file we just exported. Using a Round brush with 0 Hardness, paint white in the areas of the UVS where the hair is more dense, and darker where it is less dense. It should be completely black around the edges so the hairs fade out in those areas. Save the file and return to 3ds Max.
22 hair Density
On the Hair Generate modifier, apply the image we created into the density slot. Change the hair count to 4,000, or whatever number seems to work best for you according to your topology. Keep tweaking the shape of the brows.
23 Mirroring the brow
Click the Mirror button and select X and Copy. This will create a copy of our brow on the missing side. Feel free to tweak it to make it slightly different from the first one.