165Lighting in Virtual Environments
8.8.1 maKing sure your lighTing is seen
Because you are a diligent designer and want your project to look its best, you should plan from the very
beginning to test the performance on all sorts of platforms and under various conditions. Remember to
consider the slower machines your audience or visitors may use. In Second Life and OpenSim, take a look
at your environment using the various types of draw ranges and quality settings in the Preferences/Graphics
menu. It also behooves you to look at your scene under a variety of WindLight (or LightShare) settings in
Second Life or OpenSim because people visiting your build will do that.
8.8.2 per VerTex lighTing Versus per pixel lighTing
As you seek to pack more detail and “realism” into your scene with numerous complex materials/shaders
and lots of light sources, the demand on the graphics processor starts to elevate. This is especially the case
if your scene is being rendered as “per pixel,” meaning that the level of illumination is being calculated
for each pixel on the screen. With this approach, creation of the rendered image becomes “expensive” in
terms of processing resources. While some of the high-powered game engines like Unreal, CryENGINE,
and Frostbite Engine can utilize this form of lighting, most other game and 3D world engines need to have
another option. The use of “per vertex” lighting, which calculates the illumination at the vertex and then
interpolates the color/shading across the surface until it reaches the next vertex, is much more economical in
terms of system resources. This type of lighting is also known as Gouraud shading and is a common feature
in most 3D modeling software [5]. In Second Life and OpenSim, you can make your objects take on a richer
look by combining the basic default lighting with shader settings and special textures with baked in lighting.
Also consider exploration of the newer material settings that utilize bump maps and specular maps, as it will
provide even greater latitude in your lighting design.
8.9 PROJECT: LIGHTING THREE BASIC SCENES
The best way to learn about lighting and how to light something, or someone, is to do it. This project will help
you create three of the most basic scenarios in lighting: aportrait/daylight scene, a large night scene with an
avatar, and a still life or “product shot.”
The rst thing you should do is make sure that all ambient light in your real environment, the room around
your computer, is off or very low so you have the best view of how the lights are being displayed in your
scene. Put a small light behind your monitor so that it shines only on your keyboard from below the monitor’s
frame if you need to see the keys more clearly. Having a keyboard with lit keys is useful in this situation. Also
make sure you have turned your render settings up as high as they can go, in Avatar/Preferences/Graphics
under the General tab. You should have the Advanced Lighting Model and Ambient Occlusion boxes checked
for on. Turn down your draw distance if this drives your computer into a frenzy.
8.9.1 lighTing for a porTraiT of an aVaTar in a dayTime ouTdoor enVironmenT
As a designer, you will need to illustrate how your client’s visitors will look in the environment you are build-
ing for them. One simple way is to show the avatar within the environment in a attering light. In Figure8.5,
the avatar is showing how she looks while visiting Wheely Island at sunset. The sky is deeply colored as the
custom WindLight setting “Shambala” has the Sun/Moon color set at orange, and this strongly colored light
is showing on the screen left side of the avatar’s face.
166 Virtual World Design
FIGURE 8.5 Screen shots showing “Portrait Lighting” for an avatar. Top left image shows the Atmosphere settings
for the Shambala sunset lighting, top right image shows light position for the main (key) light, and bottom image shows
the resulting light on the face of the avatar.
167Lighting in Virtual Environments
To practice this lighting step, nd a scenic spot for your avatar and open up the Phototools menu (under the
World/Photo and Video tab on the top bar). On the main menu that appears, look under the WL (WindLight) tab
for your sky settings. Select a new sky preset and create a new sky setting in the menu panel that appears. Name
your new WindLight setting “Portrait Light” and adjust the Sun/Moon color (S/M color) and Ambient colors to
cast a warm, orangy sunset color on the scene. In the project example , these settings were (R=1.000, G=0.500,
B=0.000) for the Sun color, and (R=0.192, G=0.152, B=0.152) for the Ambient setting, dened in LSL color
enumeration in the color picker. With the LSL settings in the color picker, add in a deep red color, (R=0.477,
G=0.000, B=0.000) for the BluHrz (Blue Horizon) and a deep blue color, (R=0.073, G=0.200, B=0.400), for
the BlueDepth. These will add to the richness of the background of the sky in the scene. Feel free to slide
the HazHoz (Haze Horizon), HazDen (Haze Density), DenMult (Density Multiplier), and DistMult (Distance
Multiplier) around to shift the look of the sky and ambient environment until you like the look of it.
When you think you have a good background, go to the next step. To round out the sculptural aspects of
the avatar’s face, a front light source is added in a color matching the overall sky and ambience you just setup.
The position for this kind of portrait face lighting is usually from above and pointed down at a 45°angle, from
either side or sometimes both. This will bring out the sculptural qualities of most faces but can also bring out
the depths of older faces. A atter angle (one more parallel to the horizon) will soften older faces but tends
to wash out the sculptural qualities. In Figure8.5, this front light source, or “key light,” gives you the sense
of reected light (off the water, perhaps) on the avatar’s face. The light source and its primary focus are indi-
cated in the right side image at the top of Figure8.5, and in the lower panel you will see how it targets the
upper right side of the face. Try toggling this light on and off to see what it is actually lighting in your scene.
Work back and forth between the WindLight settings and your face lighting. You should be able to obtain
some interesting and dramatic lighting with just these simple steps.
8.9.2 lighTing for a nighT sCene in a large-size indoor enVironmenT
If you want to show off a large area of the virtual environment, you will need to utilize the Sun or Moon as
effectively and dramatically as possible. To achieve the dramatic moonlit night shot you see in Figure 8.6,
the standard WindLight setting of Lunar Morning 7 was used for the basic environment lighting. Once you
have loaded this WindLight setting in your Phototools menu, click the Edit Sky Preset button, so you can
see the Atmosphere settings in it. Because Lunar Morning 7 has a low HazHoz setting, an almost pure black
Ambient setting in LSL color notation (R=0.030, G=0.030, B=0.010) and an almost pure white Sun/Moon
(S/M color) setting in LSL color notation (R=0.840, G=0.840, B=0.804), the moonlight comes blasting in
like there is no atmosphere, creating strong shadows and highlights. To effectively show off the architec-
tural detail of the scene, a large, soft glow called a “ll light” (casting a deep blue color of light) was added
behind the avatar and raised to light the background. To accent the “moonlight” on the avatar’s face, a pro-
jector light was added in the foreground, high and out of the camera framing. This white light projector was
angled toward the avatar’s left side, and she was turned toward it slightly, so her face would catch more light.
Projectors are more difcult to focus and will cast shadows on your avatar, but the dramatic effects created
are interesting. Try setting this scene up for your avatar and see if you can create a sense of drama on the
background while lighting the avatar’s face.
8.9.3 lighTing for a produCT shoT
Sometimes, as a designer, you will be building props, furniture, or sculpture for inclusion in a virtual environ-
ment, or you may simply want to create a nice image of an object you made to sell on the Metaverse’s market-
places. In Figure8.7, a couple of abstract chess pieces (knights) are positioned on an endless chessboard.
168 Virtual World Design
FIGURE 8.6 (See color insert) Screen shots showing lighting for a night scene inside a large indoor environment.
Top left image shows the WindLight setting for Lunar Morning 7. Top right image shows positioning the background
(ll) light on the left side and the front (key) light on the right side. In the bottom image, the lines point toward the targets
of these lights.
169Lighting in Virtual Environments
FIGURE 8.7 Screen shots of settings and lighting used in a product shot of two chess pieces. In the top left image
is the Atmosphere Settings submenu from the Phototools menu and in the top right image is the composite look of the
atmosphere and the product light on the chess pieces. In the bottom panel, the targeting of this product light and the nal
image are shown. The product light has been made transparent to hide it from the observer.
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