There
are lot's of tutorials on the web about
modeling a human head, so I won't go over
the merits and differences of methods
again. There are a few things worse of
mentioning - you will get a more successful
results if you will try to model an original
face with interesting features - curved
nose, scars or strong ethnic elements
could make your rendering interesting
and believable. The best thing to do,
is to look into photographic book, National
Geographic magazines or other things like
that for inspiration. You can scan a picture
and use it as your template for modeling.
I use polymodeling for my human face,
it gives more control, and less trouble
while rendering.
First
steps
When
you have your template image ready, go
to Maya's front view, and in the camera
attribute editor create an image plane,
assign your template image to this plane.
With create polygon tool make a new polygon,
which would outline the head silhouette.
Use as little points as possible, and
try to put them in places which would
be usefull as the starting point for internal
polygon edges.
Now it's time to split the first polygon
vertically in the center, and then horizontally
at the level of the eyebrows, eyes, and
the lips. Delete the right or left side
of the head (afterwards you will mirror
it back, for now it's easier to work on
one half) and split the remaining polygons
a few times connecting them to the outer
vertices.
Try
to stay with a as low vertice count as
possible, you will have to pull them in
3d space to get the volume of the shape.
Easiest to do this is by putting another
template image (at least a simple pencil
sketch of the profile) into your side
view, and pull the vertices into the right
position. Keep your model smooth shaded,
and make all your edges soft to have a
better feedback of what you are doing.
It isn't as difficult as it sounds, the
basic shape will appear very quickly,
you might want to add some more edges
here and there to get it right, but still
try to keep it as simple as possible for
the next step.
When
you are happy with the basic shape of
the head, it's time to apply a fantastic
mel-script created by Dirk Bialluch "Connect Poly Shape". It mirrors your low
poly head and creates another subdivided
version of the head, which makes work
so much easier. You tweak a few polys
and vertices of low poly half, and see
the result on both sides of the smooth
version. You will get a very decent result
in no time.
Add
detail like eyes and ears, wrinkles (the
more the beter) dimples etc. Remember,
some of the facial detail you can get
with bump map, but the main details are
better to model, rendering results will
be much better. Another issue - a human
face is never symetric, but the result
of using the half head technique is that
you've got yourself a perfectly symetrical
model. So when the basic modeling is done,
disconnect smoothed shape, and work on
both sides separately. The more differences
there will be between the sides - the
more realistic the final render will appear.
Human
head shading
For
shading and rendering we will need other
mel-scripts and plugins. The first of
them - "AW goodies" is available from
the Alias/Wavefront
web site, and has the tool which we will
need to accomplish our task - "UV snapshot".
As it's name says - it creates a UV snapshot
of your model, which makes texture painting
task much easyer. Just asign spherical
texturing for your polygon model and make
the snapshot.
If you want to get any reasonable human
face rendering, you have to use big textures
at least 1024 x 1024, even better twice
this size, so make a snapshot of your
UV's in the resolution of texture to be.
Remember, maya doesn't handle very well
nonsquar textures, especialy for bump
maps, so try to stay with squar sizes.
Textures
If
you have a good quality photo of the face
you where modeling, you can use it for
the texture with moderated changes to
it, you will have to use some warp tools
like Elstic Reality to mach your UV layout.
Otherwise you can paint the texture yourself,
and most of time it's much more interesting.
I always startwith a bump map, it's the
one which has to be re-used in other channels
- specular and diffuse - the wrinkles
and other features you create with bump
changes physical properties of the skin
etc..
Any paint program is good, I prefer Adobe
Photoshop.
Bump
Map
Create
a new document in Photoshop of your chosen
size, make the background layer 50% gray
and load your UV snapshot as a new layer.
Change this layer mode to "Screen", reduce
it's opacity to 50% and lock it, so you
wouldn't paint on it by accident. The
rest is left for your freedom and fantasy.
I use 1px brush to paint small skin detail
and texture, then duplicating layer and
bluring it slightly.Usualy I paint lots
of small wrinkles and details arround
eyes lips and nose. I also create another
gray layer and add gausian monochrom noise
to it, then overlaying it on my painted
wrinkles, it gives a lot of fine variations.
You also make some small starlike brush
for painting bigger skin pores on the
nose, chin and lips.
