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Surfacing
the obligatory space vehicle
by Eki
Halkka
Here it is, in all of it's fast
modeled current ugliness:
Normally we would separate the
hull, wing, cockpit, engine etc. surfaces in modeler, but as
we will practice the surfacing using alpha channels and falloffs
there is only one surface this time.
I assume that you have a working
knowledge with both Lightwave and PhotoShop, what's not explained
here can be found in the manuals.
The tutorial will build on that,
but let's start with the basics.
1. Creating reference images
Open the "Tut_vehicle.lwo"
in Modeler. Type [7] and [a] to have the object in full top
view. Disable everything except the faces visibility in the
Display>Options window.
Screen grab this.
In PhotoShop, create new file and
press [CTRL+V] to paste your grab. Crop to "bounding box"
the object.
If the crop tool seems difficult
to use due to the image’s 50% gray shade, try lowering
the layer opacity to 50%. Remember to set it back to 100% before
proceeding.
Flatten image. It should look like
this:
That's it. We have made our first
reference image. We will later use the same technique to make
some more.
2. Making panels to the
wings
2.1 The alpha map
Clone the background layer. In
this new layer use Magic Wand tool to select the areas outside
the object. Fill with black, invert selection, expand by 5 pixels
and fill with white.
I added the white outline for you
to see... umm... where's the outline.
Use lasso tool to separate the
wings from the hull. Fill with black, follow the hull outlines
closely. Keep the [alt] key pressed while lassoing to have straight
lines.
The wings alpha image is ready.
Save it (Save a copy) as .IFF.
2.2 The bump map
Using the rectangular selection
tool, make some selection areas for the flaps and other panels.
Use shift key to add to a selection.
Don't worry if the selections go
outside the wings, that's the way it's supposed to be.
When you have selected descent
amount of rectangular, run Image>Adjust>Invert. [CTRL+I]
Deselect [CTRL+D]. Rename this
layer to "Panels" or whatever you find useful. It
will be used later.
Now is a good time to type [CTRL+S]
and save your work.
Copy the layer, and rename it to
"Bump". Run Filters>Stylize>Trace Contour. You
should now have thin black lines in a white background.
Make another copy of the bump layer.
Rename it to "Rivets". Select>Color Range>Highlights.
Select>Modify>Contract by
3 pixels. Set foreground color to black. Stroke (Two pixels
wide, inside)
Invert selection [SHIFT+CTRL+I],
fill with white. Deselect [CTRL+D].
Create yet another clone of this
layer, and fill it with white.
Run Filters>Texture>Patchwork
filter with Square size 1 and relief 0. You should now have
a thin lined black grid on white background. Run Image>Adjust>Threshold
to make it "1 bit". You may have to tweak the default
settings a bit.
Set layer mode to "Lighten".
You will have black dots in rows in white background. There
will be some black lines too, to get rid of them, make another
copy of the grid layer, and offset it a bit.
Don't forget to save once awhile!
What you have should look like this:
Allright, hide background, bump
and panels layers. Activate Rivets layer. Layers>Merge visible.
We will use this layer again, so make a copy of it, and then
hide it.
Hit [CTRL+I] to invert the rivets
copy layer. Set it to "Lighten"
Go to bump layer. Image>Adjust>Levels
to darken it about 50%. Merge visible. Save a copy named wing
bump or whatever you wish, as IFF.
Congrats, the bump image is ready
- unless you want to weather it, but that's another tutorial...
2.3 The diffuse/specular map
You should now have four layers
in your PhotoShop file: Background, Panels, Bump and Rivets.
Hide other layers, it's back to
panels now. Clone the layer twice. Hide the topmost copy, and
activate the lower one. Set FG & BG colors to different
shades of gray.
Run Difference Clouds filter. Rename
layer to "Diffuse" The basic diffuse map is there.
Now we will just weather it a bit.
Activate the upper copy and run
emboss filter with 90 deg. rotation, 10 pixel height and 500%
amount. Run Filter>Brush Strokes>Spatter with Spray radius
13, Smoothness 3.
Clone layer and run Filters>Blur>Motion
Blur filter with 90 deg. rotation and distance of about 40.
Set the layer opacity to about 90%. Merge the copies together.
Hide layer.
Activate panels layer and select
Shadows.
Activate the weathering layer again.
Invert [CTRL+I] and set layer mode to multiply. Deselect. Hide
panels layer, activate Diffuse layer and merge visible.
Looking much better, isn't it?
Now make two clones of the rivets
layer. Hide the original Rivets layer.
Invert the upmost layer, and set
mode lighten, with 50% transparency.
Set the other rivet copy to Multiply.
Hide other layers.
Select color range "Shadows"
and expand by 1 pixels. Fill with black. Deselect.
Apply Filters>Blur>Blur More,
about 5 times looks good. Unhide Diffuse and the other rivet
copy layer. Merge layers.
Type [SHIFT+CTRL+L] to auto adjust
levels.
The diffuse map is ready. Generally
it's a good idea to have separate Diffuse and Specular maps,
but in this case we will use this map for both.
3. Making maps for the
hull
3.1 Creating a template
Save your layered PhotoShop file
NOW if you wish to modify it later.
Flatten your image, and save it
with different name as PSD.
We will use cylindrical projection
for the hull, and the current image size is quite good for this
case. Create random black and white areas in the image with
rectangular selections and fill.
If you are less lazy than I was,
use the wings map to determine where you want your panels.
Follow the same steps as earlier,
starting from 2.1, bump map.
Here’s what your diffuse image
should look like:
Ok, that was routine, wasn't it?
I guess you wish to see these maps applied, don't you? Ok...
But first open your four .IFF images,
convert them to grayscale and save.
In the bump maps there really are
only three colors, so you can reduce the bit level to minimum.
4. Applying our new maps
4.1 The hull's basic texture
Load Tut_vehicle.lwo to Layout.
Load the five image maps we created
earlier. Apply the hull diffuse image to the Tut_surface's diffuse
channel as a cylindrical image map.
As our vehicle was created in positive
Z axis, that's the axis we will use. Click autosize. Set surface's
center to 0 in Y and X axis, as the hull was a bit deformed
after the initial lathe.
Switch your view to camera [6]
and move/rotate the object a bit to get better view.
Enable smoothing and do a quick
test render [F9]
Not that cool, but the map is aligned
ok. Go back to diffuse surface, and [CRTL+C] copy the surface
parameters. Paste [CTRL+V] the same surface parameters to specular
and bump channels.
In earlier versions than 5.6 you
can't copy this way, you will have to set the parameters manually
to each channel.
Replace the bump channel map with
hull bump. Increase texture amplitude to 200%.
Disable pixel Blending and Texture
anti-aliasing. This way you will get a crispier bump map.
New test render.
Hey, it's starting to look better!
Now let's turn the diffuse map's opacity down a bit (to about
75%), and give this baby a base surface color - and we are done
for now when it comes to hull. Test render again if you wish.
Now is a good time to save the
object!
4.2 The wings basic texture
Add new diffuse texture layer.
In the new texture layer use planar mapping, Y axis, autosize.
Load the wings diffuse image as
texture image, wings alpha image as texture alpha image.
Copy this texture to new specular
and bump layers like we did with the hull. Remember to do the
same kind of replacing/modifying with the bump channel, as we
did the last time. Yeah, test render!
I used a bluish base color here.
Don’t forget to save the object!
5. making a window
5.1 Window image map
Use same methods as earlier to
create a side [3] reference image.
Flatten image in PhotoShop. Using
the reference image as a template, draw a black window to a
new layer. Looks ugly, but never mind the uneven edges, we'll
get rid of them.
Apply Filters>Blur>Gaussian
blur. In this case amount of 10 looked ok. Fill the background
with white. Flatten image.
Apply Image>Adjust>Threshold.
Run Filters>Blur>Blur more twice.
Save as grayscale IFF. That's it
for now.
5.2 Window surface
In Layout create yet another texture
layer for diffuse. Planar image map, X axis, autosize, use the
window map for both image and alpha. Invert the alpha image.
Copy this to specular and bump
as earlier. Set specular image as negative.
Copy the map also to reflectivity
channel. Set alpha to none, and invert the texture.
Activate gradient backdrop, and
do a test render.
Heh! Not so pretty, but there's
the window.
6. Run the engines
6.1 color texture
Turn ambient light to 0%. Turn
on trace shadows. Disable gradient backdrop.
In the surface’s color channel,
create a red veins texture with 5000% coverage. This is actually
one color texture, as everything will be covered with the texture
color.
Set all other parameters to 0.
Move texture center to 65 cm. in
positive Z axis.
Set texture falloff to X 150%,
Y150%, Z 150%.
This way the texture will only
be visible to about 60-70 cm. from the texture center.
6.2. luminosity
Copy this texture to luminosity.
set value to 400%. Change texture type to Fractal noise, size
0.05, 0.05, 0.10.
Test render.
Good enough. Next in line would
be adding a lot more detail to the object, some colorization,
maybe a red nose or something, some decals etc. but that's easy
using the same methods we already have practiced.
Class dismissed, congrats!
So, here you are:
I added some lights and a skytracer
backdrop. As this surfacing stuff is quite time-consuming I
have created some ways to automate it. Check them out at my
Surfaces/Actions page. They are free.
If you liked/disliked this tutorial,
or had problems, please e-mail me.
Eki
Halkka
http://www.kolumbus.fi/erkki.halkka/
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