How to cover issues of texture, lighting, and rendering is always a tough pedagogical nut to crack. All three are intricately tied together. A red apple, when lit with green light, will render gray/brown. Small green highlights in a texture will absolutely glow if the scene is lit with that same green light. But none of these relationships will be well understood until the setup is rendered. Texturing, lighting, and rendering must work hand in hand with a very fluid two-way work flow in order to be effective.

In the last chapter, we worked on the basics of texturing. We created Lambert shaders that we were able to use images to define the color, transparency, and bump on. In this chapter, we will continue to explore shader creation a bit as we look at different material types that will exhibit different characteristics.

But the real focus will be on Maya’s lighting scheme. We are going to talk through the basic ideas of Maya’s lighting instruments and the core editable characteristics of those instruments. After this, we’ll look at how lighting works with Maya Software and Mental Ray rendering engines. Once we understand the differences here, we can start lighting our room and render with a couple of different lighting schemes and rendering solutions. Finally, we’ll look at lighting a character to best show off the character’s form.

Maya’s Lighting Instruments

The lighting instruments in Maya, in many ways, mimic the way lighting sources work in the real world, but usually not exactly. The best way to illustrate this is through a mini-tutorial in which we will place lighting instruments and then start tweaking settings to see how the things work.

But first a few general notes. When a light is created in Maya, a little gizmo will show up in the scene to represent the lighting instrument (Fig. 7.1). This gizmo gives a visual hint as to which type of lighting instrument has been placed. In all cases, the gizmo itself can be moved and rotated using Maya’s standard Move and Rotate Tools. In some cases (like the Directional Light and the Spot Light (among others)), the gizmo can also be scaled. Although remember that scaling these gizmos doesn’t always actually change the light that the instrument is emitting, it’s largely a cosmetic tool to make the gizmos easier to see.

FIG 7.1 A point light gizmo immediately after creation.

The next thing to note is that often light gizmos will make use of additional manipulator handles that can greatly assist in aiming instruments. We haven’t used the Show Manipulator Tool much so far, but it is always available in the Tool Box, and this tool is the ninth icon down (just beneath the Soft Modification Tool). With some lighting instruments (like the Spot Light shown in Fig. 7.2), when the Show Manipulator Tool is activated, two sets of manipulator handles will appear. One allows for the movement of the lighting instrument itself, and the second moves the target that the instrument is pointed at. Moving this second manipulator target can be a great way to quickly get the instrument pointing in the direction it should be.

FIG 7.2 Second set of manipulator handles made visible for the Spotlight when the Show Manipulator Handles Tool is activated.

Lastly, note that in Fig. 7.2, there is a little blue icon beneath the light gizmo. This is actually a switch that when clicked will provide additional handles on the light gizmo that allows for certain attributes to be tweaked. Each time it’s clicked, a different set of attributes for the instrument will be shown. Most of these attributes can be adjusted within the Attribute Editor (which is how we’ll do it); however, some artists find that they prefer to work with the visual representations this allows for.

Tutorial 7.1 Lighting Instrument Exploration

In this tutorial, we won’t have any finished product to show; but it will be important to see how the different lighting instruments function in Maya. If you’d like to run through it with me, then there are benefits to working with the lights. However, you could also just read along and look at the images for a good understanding of how the different instruments work.

Step 1: Set up a quick scene to illustrate the lighting (Fig. 7.3). Basically, it’s a plane, the size of the default grid, and some cylinders placed in a circle. The cylinders are all sitting on the plane.

FIG 7.3 Lighting setup.

Step 2: Establish render settings to use Maya Software. Choose Window > Rendering Editors > Render Settings. There, make sure Render using: Maya Software. Click on the Maya Software tab and change Quality: Production. Click the Close button.

Point Light

Point Lights are like suspended light bulbs. The light that comes from these instruments come from a single point in space and shoots out in all directions. They can be a great way to get started with a lighting scheme as they throw a lot of light all at once.

Step 3: Create and position a Point Light. To do this, choose Create > Lights > Point Light. This will create the instrument at 0,0,0 in world space. Use the Move Tool to move it up in Y to match Fig. 7.4 (approximately).

FIG 7.4 Positioned Point Light.

Step 4: Render the scene. Figure 7.5 shows the mouse over the Render the Current Frame button and the results of the render.

FIG 7.5 First rendering using default settings for a Point Light.

Depth Map Shadows

Depth Map Shadows are the simplest and quickest rendering of shadows. By default, Maya doesn’t render any shadows — as it’s always looking, by default, to provide the quickest rendering solution. Depth Map Shadows, essentially, are maps that paint where the light is blocked.

Within Maya Software’s renderings, light from a source will shoot out as a linear ray from the instrument and die when it hits a surface. Areas behind the struck surface receive none of the light from this source. Depth Map Shadows are simply black textures that lay across surfaces. The benefit to these are that they render very fast (in comparison to other types of shadows like Raytraced); the drawback is that they aren’t very realistic right out of the box. They are usually unnecessarily stark and can be blocky if the resolution of the shadow map is too low. Often, with a little tweaking though, some of these drawbacks can be overcome.

Step 5: Activate Depth Map Shadows. To do this, select the Point Light and look to the Attribute Editor (remember Cntrl + A will toggle the Attribute Editor if it is not open). Look for the Shadows section and expand it. Click the Use Depth Map Shadows checkbox. Render (Fig. 7.6).

 

FIG 7.6 Same light with shadows activated. Note this is rendered at a higher resolution for print purposes.

Step 6: Soften the shadow maps. Do this still within the Attribute Editor. Still within the Shadows section of the Point Light, change the Filter Size to 6. Render (Fig. 7.7).

FIG 7.7 Using a Filter Size of 6 makes for much softer shadows.

Decay Rate

Decay Rate refers to how the light falls off as it gets farther from the source. Step into your back yard and shine a flashlight at the moon, and it won’t get brighter, the light simply spreads and diffuses before it ever reaches the moon.

In Maya, we can tell light to behave in much the same way. There are several Decay Rate settings for Maya — some more realistic than others. They are Linear, Quadratic, and Cubic. Linear is the fastest rendering and Cubic is the slowest. Cubic is the most like how real light works, but it is often difficult to see the difference in a rendering — so I almost always use Linear.

Step 7: Activate a Linear Decay Rate for the instrument. This is still done in the Attribute Editor up near the top in the Point Light Attribute area. Render (Fig. 7.8).

FIG 7.8 Rendering with Decay Rate of Linear.

Step 8: Change the Point Light’s Intensity to 5. This is still within the Attribute Editor, in the Point Light Attribute area. Render (Fig. 7.9).

FIG 7.9 Render with Point Light using an Intensity of 5 with a Decay Rate of Linear.

Spot Light

Spot Lights are instruments that also emit from a single source, but instead of throwing light in every direction, these instruments throw light in a cone along the direction it is pointing. This means that the light rays from this light type splay outward from a central point.

Step 9: Change the light’s Type to Spot Light. Do this within the Attribute Editor (Fig. 7.10).

FIG 7.10 A Spot Light.

 

Step 10: Change the persp View Panel to display in Viewport 2.0. Do this via the Renderer pull-down menu.

Step 11: Change to Use All Lights. Do this by either selecting Lighting > Use All Lights within the View Panel or by letting the mouse hover over the persp View Panel and hitting 7 on the keyboard.

Step 12: Use the Rotate Tool and Move Tool to move the Spot Light up in space and aim it down toward the set (Fig. 7.11). Render (Fig. 7.12).

FIG 7.11 Using the Move and Rotate Tools to position and aim the instrument.

FIG 7.12 Render of the Spot Light as positioned in Fig. 7.11.

Step 13: Reactivate Linear Decay Rate and increase the Intensity to taste. Do frequent renders to get a more natural look.

 

Cone Angle and Penumbra Angle

Within the Attribute Editor — specific to Spot Lights are some new settings: Cone Angle and Penumbra Angle. These are meant to mimic how real-lighting instruments work. The Cone Angle is pretty intuitive; there is a visual cone on the instruments gizmo that indicates how wide the angle of the light is that emerges from the source. The Penumbra Angle might be a little more new to you.

The basics of this are that a real-theater lighting instrument actually has a series of lenses. These lenses focus the light coming from the bulb. By moving the lenses closer and farther away from one another, the light that strikes a surface will change in how crisp the edge is. Highly focused light gives razor sharp edges to where the light falls off, whereas unfocused provides a gentle falloff to the edge of the light. Of course, there are times for both looks, but knowing how to dial the edge’s softness up or down is important.

Step 14: For experiments sake, change the settings on the Spot Light to Intensity: 20 (this may need to be tweaked depending on your scene’s size), Decay Rate: Linear, Cone Angle: 45, and Penumbra Angle: 0. Render (Fig. 7.13).

FIG 7.13 A 45° Cone Angle with a 0 Penumbra Angle.

Step 15: Now, adjust the Penumbra to a non-zero value (I’m using 10). Notice in the View Panel, the edge will soften, and then when the scene is rendered, likewise the edge of the light will be soft (Fig. 7.14).

FIG 7.14 All the same settings but with a Penumbra Angle setting of 10.

Directional Light

Directional Lights are best thought of as sunlight. What a Directional Light does is throw light infinitely far from infinitely far away (there is no Decay setting). The light that comes off of a Directional Light comes in parallel rays (not from a single point in space like the Point Light and Spot Light).

Step 16: Change the instrument type to Directional Light. Do this in the Attribute Editor by changing the Type to Directional Light.

Step 17: Move the instrument to the center of the circle of columns (Fig. 7.15).

FIG 7.15 Moving the light to the middle of the cylinders.

Step 18: Take a render (Fig. 7.16).

FIG 7.16 Render of the results of a Directional Light.

Step 19: Increase the Depth Map Shadow resolution to make a cleaner shadow. Do this in the Attribute Editor. First, change the Filter setting back to 1, then try turning up the Resolution setting (in the Depth Map Shadow Attribute section) to 1024 and render. Try 2048 and render. Finally, give 4096 a shot and render (Fig. 7.18).

FIG 7.18 Same Directional Light rendered using a 4096 Depth Map Shadow.

Area Lights

If you have experience with real-lighting instruments, Area Lights are most like light boxes. In 3D, think of Area Lights as light emitting planes — they produce a very diffuse and soft light. Area Lights definitely have a hot spot middle, and the light emerges from the center of the instrument in a conical shape. But they are much more diffuse than any of the other light types.

Step 20: Change our demo light to Type: Area Light. Reactivate Decay: Linear and change its intensity to 80. Move it to approximate Fig. 7.19 and render.

FIG 7.19 Effects of an area light.

Volume Lights

Volume Lights are interesting instruments. They are perhaps the easiest to control but most unrealistic instruments in the tool chest. The basic idea is this: a volume (sphere, box, cylinder, or cone) is drawn around the center of the instrument. Light from this point source emanates outward to the edges of the volume shape. No light escapes the volume.

This means that the effects of a light can be definitively seen in the View Panel, as the volume shape can be scaled up or down. The light decreases in intensity from the center point to the edge of the volume. Check out Fig. 7.20 and see how the sphere is slightly larger than the ring of columns and how the light from this instrument stops right there.

Step 21: Change the demo light to Type: Volume Light. Change its intensity to 5. Move and Scale the instrument to the middle of the ring of cylinders and render (Fig. 7.20). Try experimenting with the size and type of volume and taking multiple renders.

FIG 7.20 Volume Light. Illumination only takes place within the gizmo’s volume shape.

Ambient Light

Ambient Light is the last light type, and we aren’t going to mess with this one much. Ambient Light can be an unhealthy crutch (although it sure has its place in some Mental Ray setups (which we’ll talk about)). What it does is produce light from everywhere and nowhere. Students too often look at a scene and say, “Shoot. It’s too dark — my lighting setup hasn’t produced enough light. I know! I’ll throw an Ambient Light in there.” This is almost always a bad idea. In real life, light comes from some place; it always has a source. Now this light bounces off of surfaces and we sometimes refer to this bounced light as “ambient,” but it came from an instrument of some type (a light bulb, or the sun, or a computer screen, etc.). Because of this, it’s important that if a scene is too dim, take some time to make intelligent and thoughtful choices to either mimic this bounced light or set up a rendering engine solution (Mental Ray and Final Gather for instance), which will calculate the bounced light and produce the extra ambient lighting.

Tutorial 7.2

So now let’s let the rubber hit the road. Now that we’ve explored the lighting instruments themselves, let’s take a look at them in a real-world situation.

In this tutorial, we will be lighting the room from Escaping the Madness that we have been working on. It provides some interesting challenges and opportunities. Namely, it provides a scene with a window, a wooden floor, furniture, and dirty walls. This will make for a really interestingly lit scene.

For this tutorial, we will be lighting the scene as though it is day time (day time is actually more difficult to light than night time), and this will provide us many opportunities to use quite a few lighting instrument solutions.

Step 1: Open the last available version of the room. If you’d like, you can download mine at http://www.GettingStartedin3D.com/ and download the starting file from the Tutorial & Support Files section.

Step 2: Start by creating the sun. We will assume that the windows are facing the west as the sun as in the late afternoon. Create a sunlight by creating a Directional Light (Create > Lights > Directional Light).

Step 3: Move the Directional Light, so that it is outside of the window and aim it down so that it will shine through the windows (Fig. 7.21). Depending on the size of your scene, you may also need to scale the Directional Light (really just scaling the gizmo that represents the instrument). A render will yield a pretty unimpressive figure (Fig. 7.22).

FIG 7.21 Positioning, scaling, and rotating the Directional Light that will act as the sun.

 

FIG 7.22 Rendering of the current lighting setup.

Step 4: Activate Depth Map Shadows and change the resolution to 4096. Render.

Step 5: Make the window panes not cast shadows. Do this by first selecting the window pane object. Then, in the Attribute Editor, look for the shape node (this will be NameOfObjectShape (in the case of the version on the supporting website it will be named Winders_ETM_Hallway_Window_GlassShape)). There expand the Render Stats section and turn off the Cast Shadows option (Fig. 7.23). Do this for all the window panes. Render (Fig. 7.24).

FIG 7.23 Turning off the window’s ability to cast shadows — which means the light will pass right through the pane.

 

FIG 7.24 Rendering with window panes not casting shadows.

Step 6: Provide illumination from windows. Do this by creating an Area Light, scaling it and positioning it to be just inside a window (do just one for now (Fig. 7.25)).

FIG 7.25 Positioning Area Light for emission from windows.

Step 7: Adjust the Area Light settings to include Depth Map Shadows (Resolution = 512, Filter = 6). Also, adjust the intensity to 0. 6 (Fig. 7.26). Render.

FIG 7.26 Results of adjusted settings for Area Light.

Step 8: Duplicate this Area Light and place appropriate for each of the other windows. Render (Fig. 7.27).

FIG 7.27 Duplicated Window Area Lights.

Mental Ray

The default rendering engine in Maya is Maya Software. This is a reasonably fast rendering engine that works with fairly simple physics models of light behavior. Some of this behavior becomes clear in renderings like Fig. 7.27 in which you can see all sorts of light streaming in, but yet, big chunks of the scene is still really dark. This is because the light hits a surface and dies, when in the real world, light bounces off of most non-black surfaces and provides further illumination to surfaces around it. And here’s where Maya Software immediately begins to show some of its restrictions.

Maya does include other rendering engines, however, and one of them handles issues like bounced light quite well. Mental Ray is another rendering engine that Maya allows access to that includes a powerful tool called Final Gather. Final Gather creates what are called stochastic samples along surfaces that sample (or look) around themselves to see what other surfaces are close. If it sees a surface close to it, it gathers the color information off that surface and tints the texture around the stochastic sample to represent the bounced light that that second surface would have provided. The net result is the look of bounced light.

So for us, this is perfect. We have only one light source — the sun — in this scene (although we are cheating a bit with the Area Lights in the windows), that we want to have bounce all over the room to provide further secondary illumination.

Now, because Mental Ray is a different rendering engine there are some things that we’ll need to adjust to make the renderings look right. The light instruments we’ve currently placed will likely prove too intense once the bounced light is calculated. The settings for transparency will need to be adjusted for our windows. And most importantly, our rendering times will be much longer (there’s just more calculations going on). But the results are generally worth the extra work and rendering times.

Before we start looking at adjustments that need to be made, make sure Maya is set up to utilize Mental Ray. To do this, chose Windows > Settings/ Preferences > Plug-in Manager. Look for the Mayatomr.mll and make sure it is checked in both the Loaded and Auto load columns.

Step 9: Turn on Mental Ray and Final Gather. Do this by choosing Render Settings (Window > Rendering Editors > Render Settings). Change Render Using: Mental Ray. Then, click on the Features tab, and in the Secondary Effects area, tick on the Final Gather option. Click the Close button. Render (Fig. 7.28).

FIG 7.28 Initial render with Mental Ray.

Step 10: Tweak light intensities. This is largely a personal preference and will take some tweaking and lots of rendering. What I did was turn my Directional Light’s intensity up to 1.5 (it is the sun after all and should be pretty intense) and turned my window lights down to 0.25 (Fig. 7.29).

FIG 7.29 Renderings with adjusted lighting intensities.

Step 11: Fix the transparency. Transparency works a little different with Mental Ray — the shaders have to be constructed just a little bit differently. To make the window panes transparent again select the material attached to them (do this either in the Hypershade or by clicking one of the window panes, and in the Attribute Editor, look for the tab that represents the material). Scroll down to the Raytrace Options section and turn the Shadow Attenuation to 0.

Step 12: Add an Ambient Light. Do this with Create > Lights > Ambient Light. Move the Ambient Light into the center of the room and change the Intensity to 0.25. Render (Fig. 7.30).

FIG 7.30 Rendering using Mental Ray, Final Gather, and a very low intensity Ambient Light to give everything an initial illumination.

Cycs

Getting dangerously close, huh? The lighting on the walls and floor is looking quite good; but those windows — even though they are transparent — just look dead. The reason, of course isthat we are looking out the windows into the depths of the 3D wasteland. They are transparent, but there is nothing to see out there — so Maya/Mental Ray render it as black.

To fix this, we’ll employ an old theater trick. A cyclorama is the backdrop that sits on the back end of a stage that often has a slight curve. It gives the illusion (albeit kind of stylized and corny) of added depth. In 3D, we can do the same thing.

This will take a few steps. First, we will model the cyc, texture it, and then make sure it doesn’t get in the way of the lighting scheme we’ve already set up.

Step 13: Model a cyc. This can be done several ways, but let’s look at a slightly different method here than we’ve used in the past. Start by creating a Bezier curve in the top View Panel to roughly mimic Fig. 7.31. Duplicate this curve and move it above the original, so there are two curves to define the bottom and top of the cyc. Select both and choose Surfaces|Surfaces > Loft (Options). Make sure the options match Fig. 7.32. The results are shown in Fig. 7.33. Name this object Cyc.

FIG 7.31 The Bezier curve that will become the cyc. Notice this is done with three anchors.

FIG 7.32 Loft Options for the Loft that creates the cyc geometry.

FIG 7.33 Lofting results.

Step 14: Create a new Lambert material to apply to the cyc. Do this by either creating a new material in the Hypershade or by right-clicking on the cyc and choosing Create New Material from the Hotbox. Name this new material Cyc_Mat.

Step 15: Find a panoramic picture to use as the base color map. A quick Google search using “countryside panorama” yields a huge collection of different options. Download the one you want and save it to your sourceimages folder.

Step 16: Back in Maya, apply this newly found panoramic image as the color map in the color channel of the Cyc_Mat. The results will look something like Fig. 7.34.

FIG 7.34 Applied panoramic image as the color map for the Cyc_Mat. Clearly, it’s upside down and needs some tweaking.

Step 17: Rotate, scale, and position the cyc as needed (Fig. 7.35). Be sure to take a look at what you can see inside the room.

FIG 7.35 Positioned cyc.

Step 18: Make the cyc not cast shadows. Remember that to do this, select the object, then in the Attribute Editor, find the shape node, and look for the Render Stats section. Turn off the Casts Shadow check box.

Step 19: Make the cyc self-lit or rather independent of the lights. We’ll do this by adjusting the Cyc_Mat. Open the Hypershade, select Cyc_Mat in the Materials tab and choose Graph > Input and Output Connections which will graph the material in the Work area. We want to use this same color map as the ambient color map. To do this, right-click the arrow at the bottom-right of the file 12 (or whatever number yours is) node and choose outColor > outColor from the Hotbox that appears. Then, right-click on the arrow at the bottom-left of the Cyc_Mat node and choose ambient-Color from that Hotbox. There will appear to be little difference in the Hypershade. But a render will yield an outside well lit (Fig. 7.36).

FIG 7.36 Cyc_Mat with activated ambient color channel.

Step 20: Clean up. Delete all history, and delete the curves used to create the cyc. Ensure that all the new elements have been appropriately named.

Step 21: Tweak lighting settings or texture settings as desired. I always find that once I get everything in, I need to make some adjustments — tweak a light here, change the color of a texture there, or even swap out entire textures. A few minutes of adjustments can really change the ambiance of a scene (Fig. 7.37).

FIG 7.37 Tweaked scene.

Shader Types

So far, the scene is looking pretty good. So far it’s also true that we’ve been using one type of Shader for all the objects — Lambert. A Lambert Shader is a good one to start with as it renders quickly and has little specialty attribute to worry about. However, there comes a time when different surfaces should have different characteristics beside changes in color.

There are actually quite a few other Shader types within Maya: Anisotropic, Phong, Phong E, and Blinn to name a few. The biggest difference (for us at this level) between these Shader types and Lambert are specular highlights and reflections.

In 3D-land, specular highlights are the little gloss highlights that smooth surfaces have. In the real world, specular highlights are really bits of reflection. The sharpness of this reflection helps define the difference between the plastic on your mouse, the plastic of your keyboard, and the surface of a metal ball bearing.

Changing a Shader type from a Lambert to something like a Blinn (for instance) is fairly simple and will take something like our metal side table and make it look much more like metal. However, as always there are tweaks and changes that must be made to the material after its type is changed. Let’s look at how to do this over the next few steps.

Step 22: Change the shader type of the Walls_Mat and name it again. The easiest way to do this is select the walls, and then in the Attribute Editor go to the tab that is the material. There, the Type can be changed to Phong (or whatever). Notice that when this is done though, it renames the material. Be sure to rename the material to something like Walls_Mat. Take a quick render to view the disastrous results (Fig. 7.38).

FIG 7.38 Default Phongshader on the walls.

Step 23: Create a Specular Map for the walls. Do this in Photoshop by opening a version of the color map (this could be the raw version in your images folder or ETM_RoomWest1 Color). In Photoshop, select all the parts of the image that are not the floor and fill them with black (you could manually paint this, or use Edit > Fill after the non-floor parts are selected). The resulting image should look like Fig. 7.39. Save it as ETM_RoomWest1 Specular.

FIG 7.39 Specular map for walls.

Step 24: Use the new ETM_RoomWest1 Specular texture map to define the Specular Color. To do this, open the Wall_Mat in the Attribute Editor (do this by either double-clicking the material in the Hypershade or tracking down the Wall_Mat node in the Attribute Editor after selecting the walls). Expand the Specular Shading section. In the Specular Color channel, import the specular map (click the checker button and create a File render node). Take a render (Fig. 7.40).

FIG 7.40 Render using a specular map to have a reflective floor but matte walls.

 

Step 25: Adjust the other objects in the scene to use alternate shaders as desired. Be sure to remember to use Specular maps to define what parts of objects should have reflectivity/specularity and which parts should be more matte. My solution is shown in Fig. 7.41.

FIG 7.41 Additional shaders adjusted.

Warnings and Pitfalls

Preparing for Final Render

Up to now, we’ve been rendering with the default quality settings in Mental Ray. Although my screen shots show a large render (1600 × 1200) so that the images would look better in print, you’ve likely been rendering at the default 640 × 480 resolution. This is good, as it ensures a faster rendering time (Mental Ray can take a long time to render). However, as your lighting scheme begins to take shape, there comes a time when you’re ready for a higher quality, or larger sized render.

To do this, we’ll need to make a few tweaks in the Render Settings. Now, we aren’t going to make an exhaustive analysis of the Render Settings window — there’s the built in documentation for that. But we will look at a few critical parts of it. Note that we will revisit this window later when we are deep into animation as being able to control this area is an important part of the animation process.

One final warning though. Students often rush to get high-quality renders and turn these settings up way too early in the process (while they are still finding the lighting scheme that works). We are about to explode our rendering times — easily doubling the time it will take to output an image. Hold off in turning these settings up until you’re reasonably sure you’re ready for a final render.

Step 26: Open the Render Settings dialog box (Windows > Rendering Editors > Render Settings).

Step 27: Define the resolution. Under the Common tab, scroll down to get to the Image Size section. There you can change the default resolution if needed. There are a number of Presets there to help plug in the appropriate numbers for things like HD television resolutions. However, you can manually enter resolution sizes if you need a render for something like print. For now, just for exploration sake, go ahead and enter Width = 1600 and Height = 1200.

Step 28: Adjust the Quality settings. Do this under the Quality tab. Change the Preset to Production. This preset will unfortunately deactivate Final Gather, so flip it back on by going to the Indirect Lighting tab and checking the Final Gather box. Render (Fig. 7.42).

FIG 7.42 Render with new quality and size settings.

Step 29: Adjust as needed. If the new rendering ends up showing flaws that you couldn’t see, go ahead and fix them. For instance, in mine, I found that the Directional Light’s shadow resolution was still too low so I increased it. The final render is at Fig. 7.43.

FIG 7.43 Final rendered high-resolution shot.

Conclusion

Lighting takes some time. It takes time to set up and takes time to render. Unfortunately, really good lighting takes a lot of small tweaks, then long render times. But don’t sell yourself short. Great-looking models are often completely decimated by poor lighting.

There are of course lots of advanced techniques that can assist in speeding this process up (rendering in passes, light linking, etc.); but before seeking these techniques out, getting a good grip on the core concepts — by practicing on “straight ahead” lighting — can still yield good looking results.

Tutorial 7.3 Character Lighting

It seems like lighting should be lighting. In reality, there are some techniques that are specific to set designs, and others that work better for characters. Often, in a project, the set will be lit one way, the character another, and then the set will use a different rendering engine than the characters that sit within the space. If rendering proves to be your area of primary interest, there are lots of fascinating techniques that await you.

However, we need to start with the basics. In this chapter, we will be looking at how to light a character. We will be lighting the alien we have created so far since we have him handy, and he presents some interesting challenges with his round body.

The techniques we will be using are loosely based on a pioneering lighting designer named Stanley McCandless. His important book, A Method of Lighting the Stage, was an important one in shaping lighting theory in American theater. Although his ideas have fallen out of vogue in many corners of theater today, his methods are still incredibly valuable in the relatively new medium of virtual lighting.

As a crude explanation of the idea, McCandless works with a Key Light that acts as the primary light source (the sun, or the overhead light bulb, etc.). In 3D, this creates very harsh shadows that leave big chunks of the character in complete blackness. McCandless’theory calls for a collection of warm-colored fill lights coming from the general direction of the Key Light. This helps diversify the colors of the character — and in particular can bring out skin tones in people. Then, a collection of cool-colored fill lights are used to light the dark side of the character. These cool-colored lights help provide illumination to the character, so that there are no black shadows, but still keep the side of the character that is away from the obvious Key Light to appear darker.

Let’s put it into practice and see if we can see better how it works.

Scene Setup

Step 1: Set your project and open the alien character from past tutorials.

Step 2: Set up the scene. To get a good idea of how this character is going to be lit, he needs to be placed on a floor. Move the character up so that he’s standing on the grid, then create a plane and place it beneath his feet (Fig. 7.44).

FIG 7.44 Set up scene.

Key Light

A Key Light is the primary light source of a lighting scheme. If you’ve done any studio photography, you are familiar with a three-light system, and if you’re not, you have undoubtedly noticed that for outdoor or indoor scenes, there is usually a primary light source that tends to dictate the shadows and brightest parts of a space.

Step 3: Create a Directional Light and position it to light the characters face. The idea is that the instrument needs to be higher than the character and pointed down. The rough position I chose is shown in Fig. 7.45.

FIG 7.45 Key Light position.

Step 4: Adjust the Directional Light’s attribute. Activate Depth Map Shadows and change the Resolution to 2048. Change the Filter to 4. Rename the Directional Light to Key_Light. Take a render (Fig. 7.46).

FIG 7.46 Render with one light source.

Warm Side Fill Lights

Figure 7.46 shows a strange render. There’s light alright, but an entire half of his face and body just disappears in black shadows. There are probably situations in which this would be what was wanted, but not for this lovable guy. We can now start filling in with fill lights. We’ll start with the warm side.

Step 5: Duplicate the Key_Light and rename it Warm_Fill_Light.

Step 6: In the top View Panel, activate the Show Manipulator Tool (activated in Fig. 7.47). There will appear two manipulation handles (one for the instrument itself and one for the target point). Move the target handle, so that it sits in the middle of the alien. Then move the instrument a little bit around the alien.

FIG 7.47 Using the Show ManipulatorTool to position a light.

Step 7: Adjust the attribute of Warm_Fill_Light. Again, do this in the Attribute Editor. Turn the intensity down to 0.3 and change the color to an amber color that very roughly matches Fig. 7.48.

FIG 7.48 Adjusting attribute of the Warm_Fill_Light.

Step 8: Duplicate and position 4 more copies of Warm_Fill_Light and position them roughly like Fig. 7.49.

FIG 7.49 More Warm_Fill_Lights. Notice there is one light there that is not selected — that’s the Key Light.

Cool Side Fill Lights

If you took a render at this point, the image would look something like Fig. 7.50. It’s warmer alright, and there is some nice filling in that is happening. However, the dark side of the alien is still too dark.

FIG 7.50 Lit with warm side fill lights.

We don’t want to keep duplicating these warm fill lights though. If we do, the character will end up totally evenly lit, and the forms of the character will be lost. Enter our cool side fill lights. These will provide illumination to the dark side of the alien, but because they are a different color, we’ll still see where the Key Light is coming from — but still be able to see the form of the dark side of the character.

Step 9: Create the cool side fill lights. To do this, duplicate any one of the Warm_Fill_Lights. Rename it Cool_Fill_Light and change the color to a desaturate blue (Fig. 7.51).

FIG 7.51 Cool side fill light settings.

Step 10: Fill out the cool side. Do this by moving the new Cool_Fill_Light, and then duplicating it four more times and positioning each of these to match Fig. 7.52.

FIG 7.52 Filling out the cool side.

Step 11: Take a render (Fig. 7.53).

FIG 7.53 Render with warm and cool side fill lights (one ring anyway).

Step 12: Fill out the fill light setup. To do this, in the Outliner, select all the Fill_Lights (both warm and cool). Group them (cntrl — G). Duplicate this group and slide it down to near the floor level. For each of the instruments in this new lower ring, select the instrument with the Show Manipualtor Tool and move the target up so that it is again on the alien’s face (Fig. 7.54).

FIG 7.54 New ring of fill lights.

Step 13: Make the floor not cast shadows. Do this by selecting the floor plane and then in the Attribute Editor go to the shape node and look for the Render Stats section. Click off the Casts Shadows checkbox. Render (Fig. 7.55).

FIG 7.55 Rendered with second set of fill lights. He’s starting to get a bit blown out.

Group Adjustments

There are some funny quirks to adjusting more than one light at a time in Maya. If you have multiple instruments selected and then make a change in the Attribute Editor (say, change the Intensity); you’d think that the intensity of all the selected instruments would be changed — but alas, that won’t happen. Using this method, Maya will simply change the intensity of the last selected instrument.

However, there are ways around this…namely the Channels Box Editor.

Step 14: Batch adjust the intensity of all the fill lights. Start to do this by going to the Outliner and selecting all the fill lights (everything with Fill_ Light in its name — both warm and cool side in both rings). In the Channel Box Editor, look for the Intensity input field within the SHAPES and change the setting from 0.3 to 0. 1. Render (Fig. 7.56).

FIG 7.56 Adjusted fill intensities.

Step 15: Tweak as desired. Now that there are the instruments to fill out the illumination, and you know how to batch adjust things like the intensity, you can turn the fill lights up or down as desired. My final tweaked solution (which included turning the cool side’s intensity up just a bit, and adding just a bit of green to the Key Light to bring out the green in the skin) is shown in Fig. 7.57.

FIG 7.57 Further group tweaks.

Conclusion

So much more fun can be had here. But hopefully this quick look at McCandless’ ideas shows how the form of the character can be highlighted while still maintaining a clear sense of where the light is coming from.

And with that we’re going to move on from lighting and rendering. We’ll visit it again briefly when we animate, but for now we’ve got the basics covered. Lighting is one of my favorite parts of 3D, and we’ve barely scratched the surface. Exciting tools like Global Illumination and Image Based Lighting didn’t even get touched here, but can make for some really nice outputs.

However, now that you know how Maya’s lights work, if lighting is your interest, you can further explore and develop your own look.

Homework

1. Light the room for night time. Remember, there needs to be a light source modeled, and don’t forget to make that modeled light source not cast shadows, so the actual Maya lighting instrument that gets placed inside the geometry doesn’t have all its light stopped when it starts casting shadows.