Figure 1.
To start off this modelling session you need to understand a little
bit about the TRANSFORM panel. (See figure 1.) The following steps
apply to any 3D object or primitive that you can select from the
TOOL panel. To model an object you need to place it into the document
window. To do this, with the tool (model) selected, click into the
window and drag out an object. To move, scale or rotate the object
you can use the panel or press key `W`, `E` or `R` respectively.
When pressing any of these keys a multi coloured `gyroscope` appears.
Try each of the modes to get used to using the gyro to get the desired
result.
TIP: To `move` along an axis, pull the coloured
end of the gyro. To `scale`, click inside the gyro and drag up or
down. To rotate, click inside the gyro and drag in the desired direction
To model or shape the object into the desired shape you need to
enter the EDIT mode, press `T or use the transform panel (Figure
1.) When in the EDIT mode the cursor turns to a red dot with a ring
surrounding it. The red dot is where your changes will be made on
the object as you model. To rotate the model in this mode click
while holding the cursor away from the object and drag up or down.
Different effects can be achieved using the transform panel by clicking
`draw pointer` (add depth to the object or remove it by holding
down ALT), `move` (pull or push an area of the object) and `scale`
(increase or decrease in size an area or polygons). (See figure
3.) To enlarge the `area of effect` on the object go to the DRAW
panel and adjust the `DRAW SIZE` slider up or down. You will notice
that the red ring grows or shrinks helping you to judge the size.
In the DRAW panel you will also find `RBG Intensity` and `Z Intensity`
which affect the amount of colour and depth applied to the object
as you model. At some stage you may need to turn `colour` or `Z`
(depth) off. This is done by selecting or deselecting the correct
box (green is selected, grey isn't). These steps are the basics
of constructing any 3D organic model in Zbrush.
TIP: The best results are achieved by keeping
the `Z Intensity low when adding depth or pulling a portion of the
model. This will let you subtly adjust the shape stage by stage
using the different tools.
Now is a good time to tell you about `snapshotting`. A model (Or
ZTOOL) in Zbrush is `live and editable` in the document window until
you `snapshot it into the image (Press CTRL+S or the `camera` Icon
shown in the transform panel in Figure 1.). Once you `snapshot`
a copy it is no longer editable and cannot be moved or rotated.
It does, however retain its depth information and can be modified
with some of the 2D tools (Simple Brush, Blur Brush etc.) The original
ZTOOL remains in the TOOL panel and can be saved as a .ZTL (Native
format) or exported as an .OBJ or a .DXF Losing the facility to
modify 3D objects was one of the first hurdles I came across in
Zbrush. It is such a departure from the norm that it takes a while
to feel comfortable with it, when you do, it becomes second nature
and going back to being able to rotate a wireframe whenever you
like seems weird.
MODELLING THE HEAD
| Start
Zbrush. Go to the DOCUMENT>MODIFIERS panel (usually on the left)
and adjust the document size to Height 2500, Width 2500 (if
you have the demo you will be limited to 640x480). Select `PRO`
to allow you to adjust the proportions. To begin modelling go
to the TOOL panel and select the Sphere3D tool. Click TOOLS>MODIFIERS>INITIALIZE
and change `Hdivide` to 512 and `Vdivide` to 256. This will
give us the maximum possible subdivision count for this object
(lots of polygons). |
|
Start Zbrush.
Go to the DOCUMENT>MODIFIERS panel (usually on the left) and adjust
the document size to Height 2500, Width 2500 (if you have the demo
you will be limited to 640x480). Select `PRO` to allow you to adjust
the proportions. To begin modelling go to the TOOL panel and select
the Sphere3D tool. Click TOOLS>MODIFIERS>INITIALIZE and change `Hdivide`
to 512 and `Vdivide` to 256. This will give us the maximum possible
subdivision count for this object (lots of polygons). Click in the
document window and drag out a sphere leaving plenty of space around
it. As we are only modelling the head at this stage the position
doesn't actually matter. At this stage we want to go straight into
`EDIT` mode so press `T` on the keyboard and a red dot/ring will
appear. Because the head we will be modelling is fairly symmetrical
we need to turn on `symmetry`.
Go to TOOL>MODIFIERS>DEFORMATIONS>SYMMETRY and select `X`. You will
now have two dots on the model. Any change made to one side of the
model is exactly duplicated on the other side saving you a lot of
work. Figure 2. To begin the modelling you will need to `pull` the
Sphere into the basic head shape. Select `Move` (W) and pull the
bottom of the sphere down. If the effect is too dramatic you can
CTRL+`Z` to undo. This is a good time to adjust the `DRAW` size
to get the right effect for this part of the modelling. Click-Hold
away from the head and rotate it slightly. Pull out a neck, back
of head, chin and a forehead. (See figure 2. Heads 1 and 2) To add
features to this cone-head we need to switch to the `DRAW PONTER`
(`Q`). Rotate the head so that it faces you and `paint` depth onto
the face. Build up the forehead, the nose, cheeks, lips and ear
bumps. Add a bump for each eye for now. To indent the model, still
in the same mode, hold down ALT and paint. Indent the cheek recesses,
nostrils and the eyeholes. Remember, you may need to reduce the
`Z Intensity` in the DRAW panel to make subtle adjustments. Try
to follow the steps in Figure 2. Keep rotating and adjusting until
you get the desired effect. (See figure 2. Heads 3-8). Add features
like frown wrinkles and bags under the eyes. If you need to move
the head on the canvas you can exit `EDIT` mode by pressing `T`
again. The gyro appears and you can select `MOVE` by pressing `W`.
Pull the gyro (grab the coloured ends) and move it in the direction
you want. To continue modelling, press `T` and re-enter `EDIT` mode.
To model the ears you can use `SCALE` (E) to enlarge the ear area.
Use `DRAW POINTER` to shape the lobe and make an indentation then
use `SCALE` (E) to reduce the ear back down to the correct size.
This will take some practice as it is not easy the first few times
you try it. Make sure you model the `bumps` in the head where the
metal hoses will fit.
NOTE: If you select another tool by mistake at this point you will
`snapshot` your head into the document - common frustrating mistake.
If this happens CTRL+`N` clears the entire layer and you will notice
a copy of your head is left in the `TOOL` panel. You can re-select
it and `draw` it back into the document and continue to edit it.
ADDING SOME COLOUR AND MATERIAL
figure 3.
Later we will be changing the material that is applied to the head.
For now we want to add some colour. With the head still in `EDIT`
mode go to the TOOL panel and select TOOL>MODIFIERS>TEXTURE and
select COLORIZE. This will flood the model with the currently selected
colour (you may not see a difference). To add colour without adding
depth turn off `Z` in the draw panel (un-select all buttons). Finally
ensure that you have `DRAW POINTER` selected (Q). Go to the COLOR
panel (on the other side of the screen usually) and pick a light
cream colour to start painting onto the head. Begin painting as
you did the modelling but notice that only colour is added, no depth
because `Z` is switched off. Paint the whole head, adjusting draw
size as needed. (The quickest way to achieve this is to flood fill
the head from the COLOR panel but it's good to practice) Change
to a slightly darker colour and begin to shade darker areas in the
eye sockets, wrinkles under the chin etc. Keep doing this until
you are happy with the effect. Figure 3. TIP: You can reduce the
amount of colour added by reducing the `RBG intensity` slider in
the DRAW panel. The effect is like a semi-transparent airbrush.
To add or change the material that is used you will need to enter
the MATERIAL panel on the left side of the screen. With your `head`
still in `EDIT` mode, select `BasicMaterial` from the options available
in the material palette. If it is not there click the top of the
panel and a full range of materials will be shown. It would be possible
to write a whole tutorial on materials so I will just give you the
parameters to input. With `BasicMaterial` highlighted go to MODIFIERS
and adjust the following: Ambient=10, Specularity=4, Noise=0.427,
Noise Radius=24. As you have the head still `live` in `EDIT` mode
in the document window all the changes will update automatically.
Now save the material, MATERIAL>MODIFIERS>SAVE. We will need this
later.
SETTING THE SCENE
Figure 5.
When you are finished colouring the head you can position it in
the document in its final position. Zoom out (minus key, plus to
zoom in, 0 to reset to 100%) until you can see the whole canvas
on screen. Exit `EDIT` mode and the gyro will re-appear. Select
`SCALE` (E) and enlarge the head to fill the canvas by clicking
inside the gyro and pulling away. Get the size correct then change
to `ROTATE` (R) and use the gyro to position the head at the correct
angle for the final image (See Figure 5.) Now use CTRL+`S` to snapshot
the head into your image. TIP: It would be a good idea to go to
the TOOL panel and save the head as a ZTOOL for future use. If you
close Zbrush without saving the ZTOOL you will lose it even if you
save the document. The head is now in place and sitting on its own
layer. We need to add two more layers, one for the background and
one for the eyes and metal hoses. Go to LAYERS>INVENTORY>CREATE
and do it twice to create two more layers. You can see them in the
LAYER panel. The `green ` coloured layer icon is the current active
layer (It should be the one with your head on it). Click into one
of the new layers. This layer can be used to import a bitmap image
(either .BMP or .PSD) as a background.
For this project I created a 2500x2500-blurred image with the same
colours as the head. You can leave it blank for now and create an
image to import later. When you import the image, if it isn't the
same size as your document, it will be stretched to fit. Click onto
the other new layer and this is where we will create the eyeballs.
CREATING THE EYES
Select a Sphere3D from the TOOL panel. Click anywhere in the document
window and drag-out a sphere. As you are on a different layer to
the `head` you will not affect it. Go to EDIT mode by pressing `T`.
Open MODIFIERS>INITIALIZE submenu. Set the mesh resolution to Hdivid=256,
Vdivid=128. Go to TOOL>MODIFIERS>TEXTURE and select COLORIZE. The
sphere will turn pure white (if it's not already). Go to TOOL>MODIFIERS>SYMMETRY
and check `Z` then `R` for RADIAL SYMMETRY. Set the radial slider
to 30. This should now give you a ring of red dots around the eyeball.
We only want to colour the eyeball and not effect the surface with
depth. Go to the DRAW panel and click the green coloured ZADD button
to de-select it. Now go to the `COLOR` panel on the other side of
the screen and select a black colour. Bring the dots on the eyeball
together and begin to draw a pupil. You can get different effect
by changing the `NOISE` slider/curve in the TRANSFORM>MODIFIERS
panel. If you find too much colour is being added go to the `DRAW`
panel and adjust the 'DRAW SIZE' and 'RBG intensity' sliders. When
you have finished the pupil select another, lighter colour for the
iris (I used a couple of shades of orange) and draw the outer ring.
Follow this with a thin line of black around the iris and then finish
the eyeball with a cream colour. At this point you can choose a
material for the eyes. To simulate a glossy wet appearance I chose
the default `Toy plastic` from the MATERIAL palette. It will update
as soon as you select it. Now we need to place them into the document.
Exit edit mode (`T`), use the gyro to scale, move and rotate the
eye into position over the socket area. TIP: This is where you realise
that the document has retained depth. With the eye in `move` (`W`)
mode you can move it along the `Z` axis (in and out of the image)
by simply clicking outside the gyro and dragging your mouse up (in)
or down (out). Get the eye into position in the socket and `snapshot`
a copy into the image with CTRL+`S`. Snapshot leaves the eye live
and `stamps` a copy so you can continue to move the eye. Using `W`
and the gyro, slide the eye across to the other socket and position
in the same way as the first. As the eyes are on a separate layer
we can `paint` on them without affecting anything else. Pick the
`SimpleBrush` from the tool menu. Pick a near-black colour from
the Colour Panel. In the draw panel set the RGB Intensity to about
7 (near transparent) and turn `Z` off. Paint a dark shadow across
the top of the eyeballs and around the edges. You can use the ALPHA
panel to try out some of the other Alpha Brushes to add veins using
a red colour.
DETAILING THE SKIN
Switch layers back to the `head` layer. To get the shiny effect
on the lips select a new material (any) from the MATERIAL panel.
Go to MATERIAL>MODIFIERS>LOAD and load the pre-saved basic material
into the new slot (overwriting the material you just chose). Increase
the settings for Specularity, Noise and Noise radius (small amounts).
Using the `SimpleBrush` with `Z` off paint the new material onto
the lips. If the settings don't look right adjust then REMEMBER:
All materials in Zbrush remain `live` and can be adjusted throughout
the creation of the image. You will need to change the colour in
the COLOR panel and keep the `RGB Intensity` low (high colour transparency)
Unlike other 3D applications that use displacement and bump maps,
the detail on this model was added with ALPHA brushes or painted
on with the Simple Brush. To `paint` the veins and cracks use the
`SimpleBrush` with different alpha brushes. The `DRAW` panel can
be set to `ZCUT`, which will then use the ALPHA brush to add cracks
and creases. You can also make your own in a paint package and import
them into the ALPHA panel. Remember you can also change the colour
setting as you go. The stitch areas were `painted` on with `Z` turned
to `ZCUT` and a red colour.
ADDING THE HOSE
Before creating the hose you need to make an alpha map in a bitmap
painting package. It needs to be approximately 500 wide by 80 high
and be black and white repeats (i.e. like a pedestrian crossing).
It needs to be a .BMP or a .PSD for Zbrush to recognise it. In Zbrush
go to the TOOL panel and select Ring3D. Go to TOOL>MODIFIERS>INITIALIZE
and change Coverage=230, Hdivide=128, Vdivide=128. Import the black
and white bitmap into the ALPHA panel. Go to TOOL>SELECTION>ALP
which then grabs the Alpha brush and applies it as a mask to the
ZTOOL. Now use TOOL>DEFORMATIONS>INFLATE to create the Hose shape.
The black areas of the bitmap are used as a mask, inflating only
the White areas. Make sure you change layers to the eyeball layer.
With the hose/ring selected in the TOOL panel draw/drag it into
the document window. Enter `EDIT` mode (`T`) and apply one of the
`Metal` materials and use a dark grey colour. Exit `EDIT` mode (`T`)
and use the gyro to position the hose. Remember `W` in+out. Snapshot
the hose into position and move the hose to the next position using
move and rotate. Repeat until all hoses are placed.
LIGHTS AND RENDERING
The last stage is adding some lights and rendering the image. In
the LIGHT panel two lights are set to `on` as default. These are
both `SUNS`. Click one of the light slots that isn't highlighted
and it should turn `green ` (on). Click into the `COLOR` panel and
pick an orange colour. Click under the LIGHT panel in the colour
box and that should change to orange. In LIGHT>MODIFIERS>TYPE choose
`GLOW`. In LIGHT>MODIFIERS>PLACEMENT drag the `PLACEMENT` button
to the document window to where you want the `glow` to appear. These
settings will only be shown when you use `BEST RENDER` in the render
panel. You will want to try different settings in the lights panel
to get the correct effect. Make sure you click `SHADOWS` to `green`
(on) in at least one of the `SUN` lights. To see the light effects
you need to render the image. Go to the RENDER>MODIFIERS panel and
highlight (turn on) `shadows`, `render depth cue` and `depth effects`.
Then click `BEST RENDER` to see the results.
MORE ZBRUSH
To learn more about Zbrush visit Pixologics website at
http://www.zbrush.com
or visit the ZBCentral Forum at
http://www.pixolator.com
