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]

Test01.jpg (3393 bytes)

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/