pjz99 opened this issue on May 22, 2007 · 9 posts
pjz99 posted Tue, 22 May 2007 at 1:19 PM
Tired of that very flat, painted look to pubic hair in renders? Here's some info on how I set up a dynamic hair layout for Hidden Forest.
This technique relies on the Hair Room. This was done in Poser 7, but it should work the same in Poser 6 as well. While this may not be the most realistic way to represent pubic hair in the world, I find this considerably better than painted hair for that purpose. I'm also doing things in a rather complicated way that I'm sure can be made simpler, this was just the way I chose to do it. I am not a realism nut, but on the other hand this approach renders well from any angle, and the results can'be be beaten by hair painted onto the texture or even displacement maps. I'm sure many people can do much better!
The nice thing about this is, if you have a character that you regularly use, you save the whole character back to the library with the hair groups pre-defined, and at most you'd have to do Animation -> Recalculate dynamics -> All hair. I've tested this and it seems to work very well.
Another advantage is that you are not limited to what your particular skin that you're using has painted onto it (if any), nor are you limited to what transmaps you might have; and it looks pretty good from any camera angle. The hairs have Poser's Hair shader config loaded on them by default, with a default color, but the color can be changed to whatever you like; and if you care to, the material itself can be made more complex for some imaginative results. You can also style and shape it any way you care to!
For the truly obsessive, this technique could probably be applied to body hair for the entire body - an idea I am entertaining myself! This application was done with Victoria 4.1, but the same technique applies to any Poser figure. Want to give your Apollo some chest hair? Maybe this can work for you!
Step 1:
If you aren't already familiar with the Hair Room, take a little quality time with the Poser manual and read about the interface, and how the settings work. It's a very intimidating interface. Thankfully, for this particular task, we don't need to use too much of it. These hairs are short enough (generally) and springy enough that they don't really care too much about gravity, and we probably don't need them blowing and twisting in the wind, and generally they're not combed and sprayed and placed just so, so for this purpose, a lot of the interface won't matter too much. It's a good idea to get familiar with what's in here though, because honestly it's a pretty powerful and cool aspect of Poser. This is considerably easier than head hair though, so it's a pretty easy place to start.
Step 2:
Decide how complex you want it. In my case, I was trying for a pretty realistic arrangement, thin at the edges and thicker towards the center. For me, this came down to six hair groups. Two outer groups for each side, and two inner groups for the center. You could just as easily decide on one or two groups and use some different methods, and come up with results that make you happy.
Step 3:
Load your figure and start placing hair groups! This is done using the Group Editor; if you haven't used Group Editor before, basically this tool allows you to select individual polygon faces of the character and add them to an arbitrary group of faces, or remove them when required.
Note that, just like dynamic cloth, you start at Frame 1 with the character in zero pose. Don't pose your character just yet, except possibly to select the faces you want to place hair on. All posing, lighting, camera placement etc. should be done at Frame 30. You may want to set the camera you're going to render with to not be animated; select the camera, and uncheck "Animating" on Parameter Dials -> Properties. You may also want to do this for lights.
Go to the Hair Room...
In the top left group of controls, "1. Hair Growth Groups", press New Growth Group.
Provide some name for this hair group. In my example there are six groups:
The reasoning for all these groups is to allow me to set things like how log the hairs are, how much they vary in length, where they're angled, how thick they are, and how curly they are. I found this approach to be more controllable than going with a single group, and easier to back out of bad combinations (see below).
Step 4:
Grow guide hairs for each group and set their properties.
For each group of hairs, in control group "2. Growth Controls", press "Grow Guide Hairs". You can select each group most accurately by clicking the Current Group pulldown in the 1. Hair Growth Groups control group. The hairs will be loaded with some default values that won't make any sense and will look very strange, so we'll modify each group appropriately.
We could mess with the Style Hairs too, but I don't think it's all that necessary with this arrangement. I found it was a little too easy to seriously mess up a hair group and get hairs pulled beneath the skin of the character, and I didn't see any way to "clear styling changes", so I ended up deleting groups and rebuilding them. If you avoid the Style Hairs tool, and you cause some problem like this, you can always go back to the parameter fields for each hair group and change them back to more sensible values.
All the "styling" done here is with Pull Back, Pull Down, and Pull Side values for each group in Growth Controls, along with a bit of Kink Strength in Styling Controls. Feel free to experiment with Style Hairs, but be warned it seems to be pretty one-way.
These hairs are pretty stiff and short, so we set Bend Resistance pretty high (I chose .97). We also check Do Collisions in the Dynamics Controls control group, to keep the hairs from crossing through each other.
The settings I used are shown below. Note that I'm only showing the right side, since the only difference for left side is that Growth Controls -> Pull Side is set positive instead of negative.
Step 5:
Pose your character and set lighting, camera, props.
Much like dynamic cloth simulation, this requires a short animation. Skip to Frame 30 on the animation slider, pose your character and set your lighting and whatnot, just as you would for a dynamic clothing arrangement.
Step 6:
Recalculate dynamics.
While this step may not be strictly necessary for all applications, it's not going to hurt you, and this is how you avoid collisions like hair poking through some nearby object. Pull down Animation menu -> Recalculate dynamics -> All hair. And go get a cup of coffee, because this takes a bit of time.
Step 7:
Ready to render! Voila!