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Sphervotic
08-28-2010, 05:44 AM
Hey there,

I am a student attending a 3D art school called the Academy of Interactive Entertainment in Australia, Sydney. I am writing this message as I am currently undergoing my final project for the year - research and a portfolio piece. The portfolio piece is anything of our choosing, however the research has to be something that can be of benefit to the industry and something we don't understand. I have chosen the topic of hair as it is something I have not really explored in my past projects and as someone who is specialising in character art, this is definately something I need to look into. The problem is that I have begun looking around the internet and I am not getting anything that is of use. I want to be able to collect various methods in creating in game hair and find the most appealing method and learn the ins and outs of it to give a tutorial to my class by the end of the project.

I've seen some really cool hair in games such as hair mods for Dragon Age: Origins and The Elder Scroll IV: Oblivion and games such as Ninja Gaiden Sigma 2. Below is an image of some of the hairstyles that I've grown very fond of and I would like to ask the community here on your opinions on how this kind of hair can be created. I've tracked the Varga hair tutorial already and was just wondering if there was perhaps other methods or perhaps how the Varga method can be adjusted or skewed to accomodate for hairstyles such as these.

Dragon Age: Origins and Ninja Gaiden Sigma 2's Momiji (http://img295.imageshack.us/img295/2791/hairstyles.png)

Additonally, how does hair dynamics work in a game engine? Can be be determined through animation or is that sort of thing entirely dependant on the engine where it can allow hair systems or physics. If there is also any reading materials out there that may be useful please link them here. I am appreciative and grateful for any help offered.

Cheers,
Sphervotic
Spaceform
08-29-2010, 12:03 PM
Hi,

The hair is in the same time fascinating and hard to get realistic in cg.

There are three different methods to build hair in cg:

1.Using a specialized hair module(plug-in)
That generates volumetric hair.This is the most realistic and time consuming method.It is used only in prerendered graphics(for now).Here you usually have all the controls to make various hair attributes and the collision and gravity controls also.

2.Transparency mapped method

Here the hair volume is builded with the geometry,usually polygons and they are mapped with a transparency map to simulate the actual separate strands.This method is widely used today both in prerendered and in real time.I think all of the games you mention relies upon this technique to render the hair.

3.Purely geometric hair without a transparency map also called the "Helmet"
This is good for cartoon type characters as their style implies.Usually the artist add some hair strands via a color map.This was used in the beginning of real time scenes in games.

Also there is a hybrid method that developers are using to get the most of the second and third method.
As for the dynamics the developers are choosing if the hair will have some physics applied or the hair will be animated manually.
Sphervotic
08-30-2010, 12:46 PM
Thank you for your insight Giziz, much appreciated.

So it seems like the transparency map method will be the focus of my presentation whilst explaining the other two methods as possible ways to create hair. How would you create hairstyles shown in the picture in the opening post, would you be able to build a polygonal shell of the hair, unwrap it and texture accordingly applying colour, normal, specularity?

The first method implies that the artist are using things like Maya Hair and Fur and plugins such as Joe Altar's Shave and a Haircut right? As it creates hair which you can control attributes such as length and collision and generally is render intensive it can't really be used with realtime gameplay. Also, what are some examples of the third method? I took at look at your portfolio and the model of the women looks quite good, is her hair an example of the third? Where it doesn't use transparency and is entirely geometric?
Sphervotic
09-11-2010, 06:45 AM
My research is coming along nicely and I think I have what I need to present at the end of the assignment down pat, however I was talking with a programmer at my college and it piqued my interest that a parallax map will really help to achieve good looking hair. This is something entirely new to me in my experience however something I definately want to explore and learn about. The programmer was talking to was saying to create a parallax map that I need to create a height map, is this all I need or are there other things to consider? And if there are more or if that is all how do I go about creating it?

Cheers,
Sphervotic
sqrlcub
09-12-2010, 08:58 PM
2.Transparency mapped method

Is there an easy to follow tutorial hidden around online for this one?
Psyk0
09-12-2010, 11:23 PM
Varga hair tutorial:
http://www.paultosca.com/varga_hair.html
sqrlcub
09-13-2010, 01:48 AM
Much appreciated, thank you.
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