Using Lighting Analysis

The values provided by the Lighting Analysis Image Overlay or the Light Meter helper objects will enable the architect or lighting designer to determine if the combination of natural and arti-ficial lighting is adequate for the type of environment being studied, or if additional fixtures or design changes are necessary. This was a very introductory look at the lighting-analysis tools in 3ds Max Design 2011. There are a number of very informative white papers on the Autodesk website that go into much greater detail about configuring and using the 3ds Max Design lighting analysis features. If you are interested in lighting analysis, you should study those resourc

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usInG lIGhtInG analYsIs | 751 33. Click the Render Production button on the Main Toolbar. After the rendering has processed, the Rendered Frame Window is updated with the results from the Lighting Analysis Image Overlay, as shown in Figure 14.83. Another win- dow, Lighting Analysis Data, also pops up; however, its content is not important. 34. Save your scene as MyMentalRayLightingA.max. Figure 14.82 The Lighting Anal- ysis Image Over- lay render effect options Figure 14.83 The Rendered Frame Window with the Lighting Analysis image overlay 752 | Chapter 14 adVanCed renderInG usInG Mental raY The values provided by the Lighting Analysis Image Overlay or the Light Meter helper objects will enable the architect or lighting designer to determine if the combination of natural and arti- ficial lighting is adequate for the type of environment being studied, or if additional fixtures or design changes are necessary. This was a very introductory look at the lighting-analysis tools in 3ds Max Design 2011. There are a number of very informative white papers on the Autodesk website that go into much greater detail about configuring and using the 3ds Max Design lighting analysis features. If you are interested in lighting analysis, you should study those resources thoroughly. The Bottom Line Apply final gathering Final gathering is an optional step in calculating global illumination that can reduce the appearance of unwanted variances or rendering artifacts in the lighting. Master It Apply final gathering to an exterior view of the Savoye project from Chapter 14, “Advanced Rendering with mental ray.” Create a contour rendering Contour renderings display dark strokes along the contours of a scene’s objects. This is an effect caused by using the mental ray Contour shaders and the parameters in the Camera Effects rollout. Master It Using the same techniques covered in this chapter, create a contour rendering of the interior of a condo scene from Chapter 6, “Creating AEC Objects.” Use the multi/sub-map material Creating a large number of unique maps to apply to repeti- tive objects in a scene to add a sense of variation or randomness can take a lot of effort. The Multi/Sub-Map rollout allows you to create one material with a number of internal variations that you can apply to objects in your scene to achieve that sense of natural randomness. Master It Create a 25 × 25 array of 1´ radius spheres, offset 3´ from each other, with a single material that will randomly change the color of the spheres through the use of the mental ray Multi/Sub-Map type of map. Use Skylight global illumination Global illumination can enhance the appeal of a scene by simulating bounced light. This can include the color bleeding effect where color is trans- ferred from one surface to another. Master It Add global illumination to an exterior shot of the Savoye scene from Chapter 8. Use mr Proxy objects Using mental ray Proxy objects in scenes that require a considerable number of identical high-poly objects can save you significant file size, system resources, and render time. Master It Create and render a 25 × 50 array of mr Proxy teapots using an eight-segment teapot as the source object. Use IES files Using Photometric Web distribution files for your photometric lights can greatly increase the realism and accuracy of your final rendered images. Master It Using the MyMentalRayIESLighting.max file you saved near the end of the chapter, change the light distribution type of PhotometricLight001 from Uniform Diffuse to Photometric Web, and select the cooper.ies file. Then render the scene. Use lighting analysis Proper accommodation of naturally available light can greatly benefit a building’s design. Using 3ds Max Design 2011’s lighting-analysis tools can help architects and lighting designers successfully study how lighting affects a project. Master It Using the MyMentalRayLightingA.max file you saved in the last exercise, cre- ate a Light Meter helper object on top of the coffee table, calculate the light meter, and render the scene, displaying the values of the Light Meter helper on the render. Chapter 15 Finishing It Off: Atmosphere, Effects, and Compositing 3ds Max Design 2011 has several features for adding the appearance of objects in your scene without actually adding any geometry. These features fall into one of two categories: atmospheric effects and rendering effects. Atmospheric effects are effects that appear to show particulate mat- ter in the air (such as mist, smoke, or even fire). Rendering effects change the appearance of a rendered scene by adding objects such as glows and starbursts, but they can also be used to add hair or fur to an object in the scene. The Hair and Fur effect can be used to simulate grass in a scene. You can also render images simulating such real-world camera effects as glare from extremely bright reflections or light sources and the depth of field created by adjusting the aperture of a camera lens. Included with 3ds Max 2011 is Autodesk Composite, a node-based compositing application that is based on the Autodesk Toxik compositor. Compositing is the process of layering image elements on top of each other and adjusting how they are blended together to create your final image. Autodesk Composite features a comprehensive toolkit to maximize your creativity, including keying, color correction, motion tracking, paint features, full HDR support, depth-of- field effects, all at resolutions up to 4K film resolution. This chapter cannot go into all the fea- tures of Autodesk Composite, but it will give you an idea how you can work with your images, and then you can use the Composite help and learning resources. In this chapter, you’ll learn to: Add an atmospheric effect•u Add a grass effect using Hair and Fur•u Add the Glare effect to a rendering•u Use DOF/Bokeh•u Create stereo-pair images•u Composite the stereo pair into an anaglyph image•u Adding Atmospheric Effects When a scene is rendered in 3ds Max, the renderer calculates, among other things, the effect of the scene’s lights on the surfaces of the geometry. By default, the scene is rendered as if the air surrounding the objects is clear and free of any particulates. In many cases, this is the correct assumption, and you wouldn’t want to add pollution, fog, or airborne particles to the scene. Yet 754 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG sometimes, adding atmosphere effects is necessary to make the scene look more realistic, which is particularly true when dealing with lighting, fog, and fire. 3ds Max has a set of features, called atmospheres, that can add the appearance of airborne par- ticles. Real-world lights cast light into their surrounding environment, and you can see the effect of the lights as both direct and indirect illumination, but you can’t see the actual light rays or light cone. When the light cone appears to be visible, such as a spotlight at a movie premier or a car’s headlights on a foggy road, what you’re actually seeing is the light rays diffusing after hit- ting airborne particles such as dust, smog, or water vapor. The Volume Light atmosphere adds the light diffusion effect to selected lights in a scene. Atmospheric effects are also helpful when adding fog to a scene, which can give the impres- sion of desolation, eeriness, or cold, wet weather conditions. In reality, fog is comprised of an immeasurable number of minute particles that capture and diffuse light rays. This would be dif- ficult to calculate and display accurately. You can represent fog in your scenes, including density changes and color variations, using the Fog atmosphere. As you can guess, the Fire effect renders as a ball or tendril type of combusting materials that can change color with distance from the fire’s center. Be aware that the Fire atmosphere, like Fog and Volume Light, appears only in rendered scenes and not in the viewports. Also note the Fire effect does not contribute any illumination to the scene. These effects are designed to work with the scanline renderer, and now that the default ren- derer is mental ray, you may find that the scanline effects don’t always work correctly. Volume Light in particular are best reserved for the scanline renderer. To create volume lights in men- tal ray, you can use a specialized shader called the Parti Volume Photon shader, placed on the Volume channel of the mental ray Camera Shaders group. The use of that shader is outside the scope of this book. Creating a volume Light There are many times when you can use a Volume light. Any time a light beam is visible as an object in a scene, this is a chance to use a volume light. Whether it’s dappled light streaming through the leaves in a forest, rays casting through a window, or even car headlights or parking lot streetlamps at night, all of these are a good use of volume lights. In the following exercise, you’ll add the Volume Light atmosphere to existing lights in a 3ds Max scene. After adding the atmosphere in the Environment and Effects dialog box, you pick the lights that will display the effect and then render the scene. 1. Open Savoye15_A.max. This file is similar to the Savoye files you worked with in other chapters, but with a darker environment and downward-facing spotlights added to the overhang. File Load: Gamma Settings If you get a File Load: Gamma and LUT warning when you open this file, choose Adopt the File’s Gamma and LUT settings. 2. If it is not already the active viewport, right-click the Camera01 viewport, and then ren- der the scene. The Rendered Frame Window should look like Figure 15.1 and show the light pools beneath each spotlight. addInG atMosPherIC eFFeCts | 755 render Camera or perspective Viewports The result of atmospheric effects can be seen only in rendered Camera or Perspective viewports and not in rendered axonometric or orthographic viewports. 3. Press the 8 shortcut key, or choose Rendering  Environment to open the Environment tab of the Environment and Effects dialog box—or you can press the Environments And Effects button in the Rendered Frame Window. 4. In the Atmosphere rollout, click the Add button to open the Add Atmospheric Effect dia- log box, as shown in Figure 15.2. 5. Click the Volume Light option and then click OK. Volume Light is added to the Effects field in the Atmosphere rollout. Figure 15.1 The first rendering of the scene Figure 15.2 The Add Atmo- spheric Effect dialog box 756 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG 6. In the Lights section of the Volume Light Parameters rollout, click the Pick Light button. At this point, you could select each light in the scene by picking them in the viewports. Some of the lights aren’t easily selected in the viewports, so you’ll need to use the Pick Object dialog box. 7. Click the Select by Name button or press the H key to open the Pick Object dialog box shown in Figure 15.3. Because only lights can be assigned to the Volume Light atmo- sphere, only lights appear in the list. 8. Highlight all the lights with names that begin with TPhotometricLight and then click Pick. The names of all the selected lights can be displayed by expanding the drop-down list in the Lights area. 9. Render the scene again (see Figure 15.4). This time the light cone can be seen from the source half the distance to the ground. Figure 15.3 The Pick Object dialog box used to select lights Figure 15.4 The rendered scene after adding the Volume Light effect addInG atMosPherIC eFFeCts | 757 photometric Volume Lights on 64-Bit Systems If you are using photometric lights with the Volume Light Atmospheric effect in the scanline ren- derer on a 64-bit system, be aware that there are reports of render artifacts or errors and that the volumetric effects don’t properly respond to the Noise parameters. We hope this will soon be rem- edied with a hot fix or a service pack. If you run into this error or any other errors, please submit a defect report against 3ds Max Design 2011 to Autodesk. Adjusting the volume Light Parameters Like most features in 3ds Max 2011, there are many parameters that can be adjusted to tweak the appearance of the Volume Light effect. The most notable are those that modify the effect’s den- sity and color. You can change the color of the volume of light to inject emotion into a scene—for example, yellow for warmth or blue for moonlight. Use density to make the effect more visible if needed. Here you will experiment with each of those parameters: 1. In the Volume area of the Volume Light Parameters rollout, click the Fog Color swatch to open the Color Selector dialog box. 2. Select a pale yellow color (255,255,230 works well) and then click OK to close the Color Selector. 3. Render the scene again. This time the hue of the lights’ cones is shifted toward yellow. Not all Instances are affected All the lights selected in this exercise are instances; therefore, adjusting one light’s parameters adjusts that parameter for all lights. However, just because an instance is a volume light, not all the instances are volume lights, so each light must be added to the Volume Light effect. 4. Increase the Density value to 8 to increase the amount of light captured by the effect. Make sure the Exponential option is deselected and then render the scene again. With Exponential checked, the light’s density falls off exponentially with distance rather than linearly, as it does when the option is off. Your Rendered Frame Window (RFW) should look similar to Figure 15.5. Figure 15.5 The scene after adjusting the Density parameter 758 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG The Exponential check box is critical to use if you intend to render transparent objects within the Volume Light or Volume Fog. You can adjust the Volume Light’s parameters further as you want. One nice tip to know is that if you put a bitmap in the Projector Map channel, you will get the bitmap throughout the volume of the light. If you need to accentuate streaks of light in a scene, this is a helpful technique. Adding Fog 3ds Max fog comes with two different fog styles: Volume Fog and Fog. With Volume Fog, a spherical, cylindrical, or box-shaped gizmo called an atmospheric apparatus is added from the Helpers category on the Create tab. The fog is then created and constrained to the boundaries of that gizmo. This fog type is good for clouds or when representing a smoke or fog effect that must be limited to a specific volume. The other type of fog atmosphere, the one that is used in this exercise, is unlimited in its extents and fills the area viewed through the camera. addinG the FoG atmoSPheric eFFect Fog is another atmospheric effect similar to the volume light but not constrained to a helper object. Let’s try it: 1. If you’ve closed any of the windows, you can reopen the Environment tab of the Environ- ment and Effects dialog box and then click the Add button in the Atmosphere rollout. 2. In the Add Atmospheric Effect dialog box, double-click the Fog option to select it, and close the dialog box. With the Fog option selected in the Effects window, the Fog Parameters rollout replaces the Volume Light Parameters rollout (see Figure 15.6). If you need to go back and adjust the Volume Light effect’s parameters, simply select Volume Light in the Effects window. Figure 15.6 The parameters for adjusting the fog addInG atMosPherIC eFFeCts | 759 3. Render the Camera01 viewport. As you can see in Figure 15.7, the Fog effect starts at the camera’s viewing plane and increases in density with distance. 4. Although this effect frames the leaves on the tree nicely, in this case you want to just show some ground fog around the building. In the Fog area of the Fog Parameters roll- out, click the Layered radio button. The Standard area grays out, and the Layered param- eters become available. 5. Layered fog has Top and Bottom parameters that set its vertical limits. Set the Top param- eter to 3´0.0˝ and leave the Bottom set to 0´0.0˝ by clicking and dragging the spinners. Don’t Obscure the Scene Make sure the camera is above the top level. If the camera’s Z position is between the Top and Bottom parameters, then it is within the fog itself, and much of the scene may be obscured. 6. Set the Falloff option to Top, so that the fog gets thinner as it reaches its upper limit. Render the scene again. Your RFW should look like Figure 15.8. The scene looks better, but you still need to work on the color and density of the fog. 7. Click the Color swatch in the Fog area, choose a dark gray/green color for the fog, and then click OK. Here we’re using RGB values 60,100,60. 8. In the Layered group, change the Density values, and render. Do this repeatedly until you find a good combination of density and color. Figure 15.7 The rendered scene after adding the Fog atmospheric effect 760 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG aSSiGninG PatcheS oF oPacitY Rather than controlling the density with the Density parameter, which results in an even den- sity throughout the fog, here you’ll use a map to randomly assign patches of opacity. This will add to the illusion of the fog, because it will not appear as an even computer-generated effect. Whenever you can add randomness to something, it tends to more naturally mimic reality. 1. Open the Compact Material Editor by clicking the Material Editor button or pressing M on the keyboard, select an unused sample slot, and then assign a Standard material to that slot. 2. Expand the Maps rollout and then click the None button next to the Diffuse color channel to open the Material/Map Browser. 3. Double-click the Noise Map option to select it, and close the Material/Map Browser and return to the Material Editor. 4. Click the Go to Parent button and then drag the Noise map from the Material Editor’s Maps rollout to the Environment Opacity Map button, as shown in Figure 15.9. 5. Choose Instance in the Instance (Copy) Map dialog box and then click OK. Because you chose Instance, any changes made to the map in the Material Editor are reflected in the scene when it is rendered. 6. Render the scene again. It’s a little better, but the changes in the fog’s density are spaced too far apart. 7. Click the Diffuse Color map button in the Maps rollout to get to the material’s noise map. 8. In the Noise Parameters rollout, set the Size value to 10 and the Noise type to Fractal to make the noise effect smaller and sharper. Then render the scene. Your RFW should look similar to Figure 15.10. 9. Close the Material Editor. Figure 15.8 The rendered scene after switch- ing to layered fog and adjusting the falloff addInG atMosPherIC eFFeCts | 761 Control the Fog’s Color with a Map Instead of using the Color swatch in the fog area to control the fog color, you can use a map. Similar to the way that you assigned a map to the Environment Opacity Map option, you could assign one to the Environment Color Map option as well. The fog would then get its colors from the map’s colors, whether the map is a bitmap or a procedural map. Figure 15.9 Dragging a map from the Material Editor to the fog parameters …to here. Drag from here… Figure 15.10 The scene after adding a Noise map to control the opac- ity of the fog 762 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG helPinG Your FoG interact with the horiZon The last feature that you want to address is how the fog interacts at the horizon. If you look in the Camera01 viewport, you’ll see a black line in the background that sits just above the top of the land on which the building sits. This is the horizon line, and its visibility is controlled with the Show Horizon option in the camera’s Parameters rollout. You can add noise at the horizon to break up the regularity of the computer-generated effect. 1. In the Layered area of the Fog Parameters rollout, select the Horizon Noise option. 2. Reduce the Size parameter to 10, and then change the Angle value to 6. The Angle value determines how many degrees below the horizon the horizon noise begins. 3. Render the scene one more time, and you should see the fog at the horizon line now broken up, as shown in Figure 15.11. 4. Save your file as MySavoye15_A.max Adding a Fire Effect Like the Volume Fog effect mentioned earlier, the Fire Effect atmospheric effect requires a gizmo to contain it. You can control whether the flames are reaching upward with tendrils or whether the flame is formed into a ball. Unlike real fire, the Fire effect does not cast any light into the scene and is almost always accompanied by a light. In this section, you’ll create a Fire effect, which you’ll add to a fire pit next to the building. 1. Open Savoye15_B.max from this book’s accompanying web page. 2. Click the Helpers button under the Create panel, expand the drop-down list, and select Atmospheric Apparatus. 3. Click the SphereGizmo button. In the Top viewport, click near the center of the fire pit at the lower-left corner of the villa and drag the gizmo until it is about the size of the center of the fire pit (see Figure 15.12). Figure 15.11 Horizon Noise con- trols the appear- ance of the fog at the horizon. addInG atMosPherIC eFFeCts | 763 4. Click the Modify tab of the Command panel and then select the Hemisphere option for the Sphere gizmo. 5. In the Front viewport, move the gizmo upward until its flat bottom is inside the fire pit. 6. Set Radius to 3´0.0 .˝ Changing the Fire’s Shape Gizmos are subject to the same transforms that other objects are, so you can use the Scale transform to change the sphere shape to more of a capsule shape. 7. With the gizmo selected, click Select and Non-uniform Scale and then drag the Z-axis handle upward, as shown in Figure 15.13, to nonuniformly scale the gizmo along the Z-axis only. 8. In the Modify panel, on the Atmospheres & Effects rollout, click the Add button. Figure 15.12 Creating the gizmo in the Top viewport Figure 15.13 Scale the atmo- spheric apparatus along the Z-axis. 764 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG turning Off an atmospheric effect You can turn off any atmospheric effect by selecting it and deselecting the Active option in the Atmosphere rollout. You can force 3ds Max to not render any atmospheric effects by opening the Render Setup dialog box, selecting the Common tab, opening the Common Parameters rollout, going to the Options section, and deselecting the Atmospherics option. 9. In the Add Atmospheric Effect dialog box, double-click the Fire Effect option to select it, and close the dialog box. 10. Open the Environment and Effects dialog box; with the Fire Effect option selected in the Atmosphere window, the Fire Effect Parameters rollout (see Figure 15.14) appears below the Effects window. 11. Render the scene; your RFW should look like Figure 15.15. Figure 15.14 The Fire Effect Parameters rollout Figure 15.15 The rendered scene after adding the Fire effect addInG atMosPherIC eFFeCts | 765 12. In the Fire Effect Parameters rollout’s Shape section, change Flame Type to Tendril and increase the Stretch value to 3. Stretch elongates the tendrils along the Z-axis. 13. In the Characteristics section, change Flame Size to 5 and Flame Detail to 5 to give the effect well-defined tendrils. Finally, reduce Density to 10. 14. Render the seen again to see the result of your parameter changes. Your rendering should look similar to Figure 15.16. addinG a liGht to the Scene As mentioned earlier, the Fire effect does not add illumination to the scene. In the real world, the light from the flames would spill onto the building and ground. You therefore need to add a light to complete the illusion. To do this, just follow these steps: 1. From the Command panel, choose Create  Lights  Photometric  Free Light and then click near the Atmospheric Apparatus gizmo in the Top viewport. 2. Click the Align button on the Main Toolbar, and align the center of the light with the cen- ter of the gizmo. 3. Click the Modify tab. In the Intensity/Color/Attenuation rollout, click the Kelvin option, and then click the Filter Color swatch. 4. In the Color Selector that opens, choose a bright yellow or orange color to set the light color. 5. In the Intensity area, set the Candelas (cd) value to 3000 to double the light’s intensity. 6. In the Colors section of the Environment and Effects dialog box, click the red Outer Color swatch and increase the redness by changing the RGB values to 227,12,12. Click OK. 7. On the Shadow Map Params rollout, change the Bias to 0.01 and the Size to 1024. Figure 15.16 The Fire effect after adjusting the parameters 766 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG 8. In the Logarithmic Exposure Control Parameters rollout, reduce the Brightness value to 50 to darken the scene a bit and make the fire pop. 9. Render the scene; your RFW should look similar to Figure 15.17. animatinG the Scene Fires are not static; they are continuously churning and moving elements. To sell this effect in an animation, follow these steps to animate both the fire and the light: 1. Move the Time slider to frame 100 and then click the Auto Key button. 2. In the Motion area of the Fire Effect Parameters rollout, set the Phase value to 12 and the Drift value to 20. 3. Select the light in the fire pit and change the Filter color to a brighter yellow red and the intensity to 4000 cd. 4. Move the Time slider to 50, and then set the filter color to a light red and the intensity to 2700 cd. 5. Select the gizmo and then add a Noise modifier to it. In the Strength area, change the X, Y, and Z values to approximately 35 ,´ -30 ,´ and 4 ,´ respectively. 6. Move the Time slider back to frame 100, and then change the X, Y, and Z values so that the Noise modifier distorts the gizmo differently over time. 7. Click the Auto Key button to turn it off. 8. Open the Render Setup dialog box and choose Active Time Segment in the Output area. 9. Save your file as MySavoye15_B.max. It’s always prudent to save your file before you begin a render. If the computer crashes during a render, you haven’t lost any work on your Max file this way. Figure 15.17 The rendered scene after adding a light usInG haIr and Fur to add Grass | 767 10. Click Files in the Render Output section, give the file a name, choose AVI or MOV as the file type, make any setup changes you prefer, and then click the Render button. Generally, rendering directly to a movie format is not a smart way to work. When you are rendering a large number of frames, you will lose the entire movie if 3ds Max or your system crashes. Also, rendering directly to a movie file bakes the compression into the file. You should render to a sequence of uncompressed frames (then if the system crashes, you haven’t lost too much time and can restart the rendering at the last completed frame) and then use the Video Post tool in 3ds Max 2011 or the Composite application to generate a movie file from the sequentially numbered frames. In this case, you’ll take a chance and render directly to a movie. This could take some time, so you might want to take a short break here. 11. Play your rendered animation in Windows Media Player or Apple QuickTime—or you can choose View Image File from the Rendering menu, and this will automatically launch the correct player from within 3ds Max. The fire churns well, and the colors change nicely. You should consider taking this exercise a little further by animating the position of the light and the radius of the gizmo. You could even use soft selection to put a noise modifier on the branches of the tree and animate the noise modifier similar to the one on the gizmo to give the appearance of the tree swaying in a gentle breeze. Using Hair and Fur to Add Grass 3ds Max has several nonatmospheric effects that are added through the Effects tab of the Environment and Effects dialog box. Although most of these are rendering effects, such as Motion Blur, Film Grain, and Lens effects (stars, glows, lens flares, and so on), there is also the Hair and Fur effect. Although there isn’t much call for hair or fur in most architectural render- ings, the effect can also be used to create convincing grass and other ground cover. Like the atmospheric effects, the Hair and Fur effect can be rendered only in Perspective and Camera viewports. Rendered hair or fur is a combination of applying the Hair and Fur modifier to an object or spline in your scene and applying the Hair and Fur render effect, which is automati- cally added to the Environment and Effects dialog box when you apply the modifier. 1. Open Savoye15_C.max. This file is similar to the Savoye files you worked with earlier in this chapter, but with a lighter environment, no atmospheric effects, and the Ground object was replaced with a plane that has been edited so that there are no faces beneath the building. The Hair and Fur effect is assigned to an entire object and can’t have only a portion of an object passed up to it in the modifier stack. The assigned renderer is mental ray. 2. Select the ground object, the object named Plane01. 3. Apply the Hair and Fur (WSM) world space modifier to the ground. A small percentage of the actual number of hairs appears in the viewports. As you can see in Figure 15.18, the hairs are much too long. 768 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG 4. Open the Effects tab (not the Environment tab that you’ve used so far) of the Environ- ment and Effects dialog box, and you’ll see that the Hair and Fur effect was automatically added to the Effects window. 5. Select the Hair and Fur effect. The Hair and Fur rollout appears at the bottom of the Effects tab. 6. In the Hair Rendering Options section of the Hair and Fur rollout, make sure the mr Prim option is selected from the Hairs drop-down list. This option designates a procedural mental ray shader as the engine that renders the hairs. Adjusting the Hair and Fur Parameters The grass looks like huge, rectangular stalks sitting on the ground plane, and the color needs some work as well. In this section, you’ll size the grass better and change the color. 1. With the Plane01 object selected, expand the Hair and Fur (WSM) General Parameters rollout on the Modify tab. 2. Set Scale to 1.75 to decrease the size of the hair strands, or in this case, grass blades. Set Cut Length to 75. 3. Set Rand. Scale to 30 so that each blade’s length is not exactly the same and can vary 15 percent above or below the standard length. 4. Decrease the Hair Segments value to 3. The grass isn’t seen up close enough to warrant the extra detail given by the larger number of segments. Hair and Fur gets its color from the Material Parameters rollout and not the Material Editor. You can control the color at the base of the blade (Root Color) and the tip (Tip Color) and allow a variance between the blades. 5. Expand the Material Parameters rollout. 6. Click the small gray button to the right of the Root Color swatch. This is how you assign a map, rather than a color, as the source for the grass color. Figure 15.18 The hairs as they first appear in the viewport usInG haIr and Fur to add Grass | 769 7. In the Material/Map Browser that opens, choose the Scene group to display only the maps that exist in the current scene. 8. Double-click the Surface Shader: Map # 8 (GRASS2.jpg) map. 9. Choose the Instance radio button in the Instance or Copy? dialog box and then click OK. A capital M appears on the button to indicate that a map is controlling the color. 10. Click the Tip Color swatch and then in the Color Selector assign a light green color simi- lar to 70,105,35. The blades will now transition from the map’s color at the root to the assigned tip color. Mutants are allowed If you want to have random hairs that possess their own color, much different than the Root and Tip Color values, assign a color to the Mutant Color swatch and increase the Mutant % to more than 0.0. 11. Render the Camera01 viewport. The scene is not quite where we want it (see Figure 15.19). Refining the Ground with the Hair and Fur Parameters Two problems exist in the scene: first, a massive number of grass blades are needed to sell the illusion of a lawn, and second, the ground object is very large. In this exercise, you’ll start by deleting and reconfiguring the ground plane to make it smaller and then finish by refining the Hair and Fur parameters. 1. Make the Top viewport the only viewport, and then zoom out so that you can see the entire scene. Figure 15.19 The rendered scene after changing several Hair and Fur parameters 770 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG 2. Turn off the UVW Mapping and Hair and Fur (WSM) modifiers and then click the Edit Poly modifier. If a Warning dialog box appears, click the Hold/Yes button. 3. To access the Polygon sub-object level, press 4 on the keyboard, and then select the poly- gons shown in Figure 15.20 and delete them. 4. Access the Vertex sub-object level by pressing 1 on the keyboard. Move the perimeter ver- tices to adjust the ground plane as shown in Figure 15.21. The smaller-sized ground plane will display the same number of rendered grass blades, but they will be much denser. 5. Exit the Vertex sub-object level and then turn the other modifiers back on. It’s important to make sure you’ve selected the Edit Poly object level—otherwise, you will be passing an empty selection set to the Hair and Fur modifier. 6. Select the Hair and Fur (WSM) modifier and then access the General Parameters rollout. 7. Increase the Hair Count to 300,000. This may seem like a large number, but it’s not uncommon for this value to be set to 5 to 10 million. 8. Reduce Scale to 0.5 and Root Thick to 0.5. These parameters shorten the blades even more and decrease the thickness at the base. Figure 15.20 Delete the selected polygons. Figure 15.21 Move the vertices to achieve this shape. usInG Glare | 771 9. Render the Camera01 viewport one more time. Note that this could take a very long time, depending on your computer’s processor and memory. This rendering calculation might take several hours using mental ray. Your completed grass should look similar to Figure 15.22. 10. Save your file as My_Savoye15_C.max. Using Glare Earlier in this chapter you rendered a Volume Light effect and read about the Parti Volume Photon shader, which can re-create the dispersion of light against particulates in a medium. Other effects can also be simulated with the mental ray renderer in 3ds Max. Assigning the Glare Output Shader In a physical camera, be it film or digital, extremely bright lights or reflections that are viewed through the lens can reflect and refract on the film emulsion or on the surface of the digital sen- sor. This effect is called glare. 1. Open the Savoye15_D.max file from this book’s accompanying web page. This is similar to the Villa Savoye files that you worked with earlier in this chapter, but with some additional detail around the villa and some spheres of various sizes and with different materials placed out in the grass. 2. Right-click the Camera.View.3DFRONT viewport to select it. 3. Click the Render Production button to have mental ray render the viewport. The Rendered Frame Window should look like Figure 15.23. Figure 15.22 The final rendering after adjusting the ground plane and modifier parameters 772 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG Figure 15.23 The rendered view 4. Right-click in the Rendered Frame Window. The mouse cursor turns into an eyedropper, and you are presented with the pixel data dialog box that tells you about the pixel that the eyedropper is sampling. Move the eyedropper over the bright portion of the large white sphere and look at the numbers in the pixel data floating dialog box. The dialog box should look like Figure 15.24. Notice that the RGB values for that pixel in the Real column are greater than 1.0. This is because the Rendered Frame Window is set to 32 Bits per Pixel and is displaying floating- point values of the High Dynamic Range rendering. 5. Right-click again in the Rendered Frame Window, and put the eyedropper over the reflec- tion of the sun on the brass sphere (it’s the middle one). You might have to use the scroll wheel on your mouse to zoom into the image to accurately pick the hot spot. This time the RGB values are much higher; they almost reach 3.0. In a real film or digital camera, when extremely intense light hits the film or the sensor, the light can disperse through the celluloid or reflect off the surface of the sensor, creating a halo around the bright areas. You can simulate this effect in mental ray with the Glare shader. You will re-create this effect now. Figure 15.24 The pixel data dialog box usInG Glare | 773 6. Click the Render Setup button on the Main Toolbar. Go to the Renderer tab and scroll down to the Camera Shaders group of the Camera Effects rollout, as shown in Figure 15.25. 7. Click the check box in front of the button labeled DefaultOutputShader (Glare) to enable that shader channel. 8. Open the Slate Material Editor. 9. Click and drag the DefaultOutputShader (Glare) button to the Active View1 Window of the Slate Material Editor, select Instance, and click OK on the Instance (Copy) Map dia- log box. 10. Click the plus symbol next to Additional Params on the DefaultOutputShader (Glare) node, as shown in Figure 15.26. 11. Click the up arrow next to Quality and set it to 3. 12. Click the up arrow next to Spread and change it to 3 as well. 13. Click the 500 next to Resolution For, and change the value to 640, the horizontal resolu- tion that you have been rendering the scene at. Figure 15.25 The Camera Shad- ers group Figure 15.26 Click to display the additional parameters. 4. Right-click in the Rendered Frame Window. The mouse cursor turns into an eyedropper, and you are presented with the pixel data dialog box that tells you about the pixel that the eyedropper is sampling. Move the eyedropper over the bright portion of the large white sphere and look at the numbers in the pixel data floating dialog box. The dialog box should look like Figure 15.24. Notice that the RGB values for that pixel in the Real column are greater than 1.0. This is because the Rendered Frame Window is set to 32 Bits per Pixel and is displaying floating- point values of the High Dynamic Range rendering. 5. Right-click again in the Rendered Frame Window, and put the eyedropper over the reflec- tion of the sun on the brass sphere (it’s the middle one). You might have to use the scroll wheel on your mouse to zoom into the image to accurately pick the hot spot. This time the RGB values are much higher; they almost reach 3.0. In a real film or digital camera, when extremely intense light hits the film or the sensor, the light can disperse through the celluloid or reflect off the surface of the sensor, creating a halo around the bright areas. You can simulate this effect in mental ray with the Glare shader. You will re-create this effect now. 774 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG 14. Click the Render button to see the image with the glare applied. You will see the effect on the three spheres, as shown in Figure 15.27. When you are rendering outdoor scenes using the mr Sun and Sky, be careful when using the Glare shader. The Sky itself is so intense that often it will be affected by the shader as well, and there can be an especially bright section near the horizon. 15. Save your scene as My_Savoye15_D.max. Using Depth of Field Another in camera effect that you can simulate with the mental ray renderer is depth of field. Depth of field (DoF) is created by light rays hitting the image plane from many different direc- tions when the aperture in the lens is wide open. When the aperture is small, only parallel rays of light can hit the image plane and the depth of focus is not as pronounced. 1. Open the DepthofField.max file from the book’s website. 2. Right-click in the Camera002_CoffeeTable viewport to make it active. 3. Click the Render Production button on the Main Toolbar to render the camera view. The Rendered Frame Window should look like Figure 15.28. Figure 15.27 Glare on the three spheres Figure 15.28 The rendered view usInG Glare | 775 4. Click the Render Setup button on the Main Toolbar and click the Renderer tab. 5. Scroll down to the Camera Effects rollout and click the button labeled None next to the checked Lens shader. 6. On the Material/Map Browser, expand the Maps  mental ray group if it isn’t already, and select Depth of Field/Bokeh, as shown in Figure 15.29. Then click OK. Next, you’ll adjust the depth of field: 1. Open the Slate Material Editor. 2. Drag the Depth of Field/Bokeh shader to the Active View1 Window of the Slate Material Editor. 3. Double-click the Depth of Field/Bokeh node to access the settings in the Parameter Editor. 4. Set the Focus Plane to 5´10 .˝ radius of Confusion The radius of confusion is a physical quality of a camera system involving the lens and the focal distance and is extremely mathematical and difficult to describe. If you are interested in reading about this concept and aren’t scared off by extreme math, there are a number of wiki articles about the radius or circle of confusion that you can find online. 5. Change Blade Count to 7. 6. Save the scene as My_DepthofField.max 7. Click the Render button on the Render Setup dialog box. When the Missing Map Files dialog box opens, click Continue. The finished rendering in the Rendered Frame Window should look like Figure 15.30. Figure 15.29 Select Depth of Field/Bokeh. 776 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG This rendering will take significantly longer than the previous rendering because of the Depth of Field/Bokeh shader, even with only four samples and the low anti-aliasing settings. If you don’t want to wait for this image to render, you can look at Figure1530.tif, which you can download from this book’s website. When you look at the finished rendering or Figure1530.tif, you should see that the gray dual-spouted vessel and the wineglass are sharp and detailed and that everything in front of or behind those two objects is out of focus. Increasing the Samples value in the Depth of Field Parameters rollout of the shader and increasing the Minimum and Maximum Samples per Pixel values in the Render Setup dialog box can greatly increase the quality of the out-of-focus areas, but at a significant cost of greatly increased render time. A more efficient way to create the appearance of depth of field in this rendering would be to render out the image with a Z-Depth channel and then use a compositing or image manipula- tion application to create the out-of-focus effect you desire. You will now render an image that has a Z-Depth channel and other channels that you could use on your own in Autodesk Composite to create different effects. 1. Save the scene as My_DepthofField_02.max 2. Open the Render Setup dialog box. In the Camera Shaders group, right-click the Depth of Field/Bokeh shader and select Clear to remove it, as shown in Figure 15.31. 3. Click the Render Elements tab and click the Add button. 4. Hold down the Control key to multi-select the Lighting, Material ID, Reflection, Refraction, Shadow, and Z Depth Render Elements options, and then click OK. Figure 15.30 The rendering with DOF/Bokeh Figure 15.31 Clear the Lens shader. usInG Glare | 777 5. Click the Common tab of the Render Setup dialog box and click the Files button in the Render Output group, as shown in Figure 15.32. 6. In the Render Output File dialog box, browse to the folder where you saved the files from the book’s website, and in the File Name field enter MyTableTop. 7. Click the Save As Type drop-down menu and select OpenEXR Image File (*.exr, *.fxr) from the list. 8. Click the Save button, and the OpenEXR Configuration dialog box will open. 9. In the Render Elements group, click the Add button, select all the Render Elements listed, and click OK. 10. The OpenEXR Configuration dialog box should look like Figure 15.33. Click OK. 11. Click the Render button to have mental ray render and save the file. This file is also pro- vided as TableTop.exr with the rest of the files from this chapter in case you do not want to render it. A high-resolution TableTop_DOF.tif with higher-quality sampling on the Depth of Field/Bokeh shader and the camera’s anti-aliasing is also provided with this chapter’s downloads. Figure 15.32 Click the Files button. Figure 15.33 The OpenEXR Configuration dialog box 778 | Chapter 15 FInIshInG It oFF: atMosPhere, eFFeCts, and CoMPosItInG Creating Stereoscopic Renders in 3ds Max One of the most popular effects of the day is the resurgence of 3D, aka stereoscopic presenta- tion. Many big movies being released are in 3D, from children’s and family movies to the big action extravaganzas. Stereoscopy was first developed back in the 1830s and involves giving each of the viewer’s eyes its own unique view of a scene. Each view is separated by the interocular distance—in other words, the distance between the viewer’s two eyes. The intraocular distance for the average adult is about 2.5 .˝ This brings up some interesting possibilities and phenomena, because stereo-pair images created for viewing by children should be designed with a smaller intraocular distance. Also, certain types of images will need to be designed with a larger intraoc- ular distance to exaggerate the perception of depth. Your brain interprets the two images and, using cues from the perspective of each image, you perceive a sense of depth from the stereo pair. Stereographic images are also now being used in architectural and engineering graphics. Whether this too is just a fad or not, we won’t know yet. This book cannot go into the rules, theory, or philosophies of stereography, and there are many, many of them, but you will get a quick tuto- rial of how to set up a scene with two cameras and how to render the scene in stereographic 3D. If you don’t have a pair of anaglyph stereo glasses to view the finished renders, it is easy to find a store online that will sell you Red/Blue stereo glasses, which will be for the format of stereo vision that you will be using. Other methods of displaying stereographic imagery require polar- ized lenses, dual-synced projectors, or very high-end computer displays with synced LCD-shutter glasses. 1. Open the Savoye_15E.max file. This is very similar to the first file you used earlier in this chapter. You will rename the existing camera in the scene and add a new camera. 2. Click the Select by Name button from the Main Toolbar; in the Select from Scene dialog box, select the Camera.View.3DFRONT object and click OK. 3. On the Modify tab, rename the camera to Right-Eye. Stereographic rendering in 3ds Max There are a number of resources on the Internet for creating stereoscopic renderings from 3ds Max. Louis Marcoux has an eight-part video tutorial that goes into much greater detail on the topic, including creating camera rigs and compositing the resulting images in Video Post using MAXScript. You can find those videos and more tutorials at his website: www.louismarcoux.com. 4. With the Right-Eye camera selected, go to the Edit menu and select Clone. 5. In the Clone Options dialog box that appears, select the Instance option and in the Name field enter Left-Eye, as shown in Figure 15.34. Then click OK. Figure 15.34 Clone the selected camera. CreatInG stereosCoPIC renders In 3ds Max | 779 6. With the Left-Eye camera selected, click the Select and Move tool from the Main Toolbar. 7. Click the Reference Coordinate System drop-down menu and change it to Local, as shown in Figure 15.35. 8. Make sure the Transform Type-In is set to Absolute mode and enter -2.5˝ in the X Coordi- nate type-in field. Then press Enter on the keyboard. You now have two cameras targeted at the same point in the scene and you are ready to ren- der out the Right and Left eye views, as shown in Figure 15.36, which presents the Left-Eye and Right-Eye cameras in the lower two 3ds Max viewports. Changing the two side-by-side view- ports to display the stereo-pair cameras is often a good check to see how well the stereo effect is composed. This quick technique will let you render a stereo pair once you have determined the view you want with one camera. If you want to have a camera rig where you can change the focal target or change the views, you will need a more robust set

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