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4.In the Logarithmic Exposure Control rollout, set the Brightness value to 60, set the Contrast value to 100, and enable the Desaturate Low Levels option.

5.In the Render Scene dialog box, click the Render button again to see the updated rendering.

The image on the right of Figure 41-18 shows the rendered image with exposure control enabled.

Figure 41-18: This rendered image shows an image before and after exposure control was enabled.

Summary

This chapter covered the basics of producing output using the Render Scene dialog box. Although rendering a scene can take a long time to complete, Max includes many settings that can speed up the process and helpful tools such as the Rendered Frame Window and the RAM Player.

In this chapter, you

Learned to work with ActiveShade window

Discovered how to control the various render parameters

Configured the global rendering preferences

Learned about the command-line rendering interface

Created VUE files

Learned to use the Rendered Frame Window and the RAM Player

Saw the different render types

Explored the Panoramic Exporter and Print Size Wizard tools

Learned to use the Environment panel to change the background color and image

Learned how exposure controls can work

The next chapter covers atmospheric effects such as fog and fire.

Using Atmospheric

Effects

In the real world, an environment of some kind surrounds all objects. The environment does much to set the ambiance of the

scene. For example, an animation set at night in the woods has a very different environment than one set at the horse races during the middle of the day. Max includes dialog boxes for setting the color, background images, and lighting environment; these features can help define your scene.

This chapter covers atmospheric effects, including the likes of clouds, fog, fire, and volume lights. These effects can be seen only when the scene is rendered.

Creating Atmospheric Effects

The Environment and Effects dialog box (keyboard shortcut, 8) contains rollouts for adding atmospheric effects to your scene, but the first question is where. Atmospheric effects are placed within a container called an Atmospheric Apparatus gizmo, which tells the effect where it should be located. However, only the Fire and the Volume Fog effects need Atmospheric Apparatus gizmos. To create an Atmospheric Apparatus gizmo, select Create Helpers Atmospherics and choose the apparatus type.

The three different Atmospheric Apparatus gizmos are BoxGizmo, SphereGizmo, and CylGizmo. Each of these has a different shape similar to the primitives.

Working with Atmospheric Apparatus

Selecting a gizmo and opening the Modify panel reveals two different rollouts: one for defining the basic parameters such as the gizmo dimensions, and another labeled Atmospheres & Effects, which you can use to Add or Delete an Environment Effect to the gizmo. Each gizmo parameters rollout also includes a Seed value and a New Seed button. The Seed value sets a random number used to compute the atmospheric effect, and the New Seed button automatically generates a random seed. Two gizmos with the same seed values have nearly identical results.

42C H A P T E R

In This Chapter

Using Atmospheric Apparatus gizmos to position atmospheric effects

Using the Fire effect

Working with fog

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Adding effects to a scene

The Add button opens the Add Atmosphere dialog box where you can select an atmospheric effect. The selected effect is then included in a list in the Atmospheres & Effects rollout. You can delete these atmospheres by selecting them from the list and clicking the Delete button. The Setup button is active if an effect is selected in the list. It opens the Environment and Effects dialog box. Adding Atmospheric Effects in the Modify panel is purely for convenience. They can also be added using the Environment and Effects dialog box.

In addition to the Modify panel, you can add atmospheric effects to the scene using the Atmosphere rollout in the Environment and Effects dialog box, shown in Figure 42-1. This rollout is pretty boring until you add an effect to it. You can add an effect by clicking on the Add button. This opens the Add Atmospheric Effect dialog box, which includes by default four atmospheric effects: Fire Effect, Fog, Volume Fog, and Volume Light. With plug-ins, you can increase the number of effects in this list. The effect that is selected is added to the Effects list in the Atmosphere rollout.

Figure 42-1: The Add Atmospheric Effect dialog box lets you select atmospheric effects.

You can delete an effect from the current Effects list in the Environment and Effects dialog box by selecting the effect and clicking the Delete button. The effects are applied in the order in which they are listed, so the effects at the bottom of the list are layered on top of all other effects. To the right of the Effects pane are the Move Up and Move Down buttons, used to position the effects in the list. Below the Effects pane is a Name field where you can type a new name for any effect in this field. This enables you to use the same effect multiple times. The Merge button opens the Merge Atmospheric Effects dialog box, where you can select a separate Max file. You can then select and load any render effects from the other file.

Using the Fire Effect

To add the Fire effect to the scene, click the Add button and select the Fire Effect selection. This opens the Fire Effect Parameters rollout, shown in Figure 42-2. At the top of the Fire Effect Parameters rollout is the Pick Gizmo button; clicking this button lets you select a gizmo in the scene. The selected gizmo appears in the drop-down list to the right. You can select multiple gizmos. To remove a gizmo from the list, select it and click the Remove Gizmo button.

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Figure 42-2: The Fire Effect Parameters rollout lets you define the look of the effect.

Note	The Fire effect renders only in non-orthographic views such as Perspective or a camera view.

The three color swatches define the color of the fire effect and include an Inner Color, an Outer Color, and a Smoke Color. The Smoke Color is used only when the Explosion option is set. The default red and yellow colors make fairly realistic fire.

The Shape section includes two Flame Type options: Tendril and Fireball. The Tendril shape produces veins of flames, and the Fireball shape is rounder and puffier. Figure 42-3 shows four fire effects. The left two have the Tendril shape, and the two on the right are set to Fireball. The difference is in the Density and Flame Detail settings.

Figure 42-3: The Fire atmospheric effect can be either Tendril or Fireball shaped.

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The Stretch value elongates the individual flames along the gizmo’s Z axis. Figure 42-4 shows the results of using the Stretch value. The Stretch values for these gizmos, from left to right, are 0.1, 1.0, 5.0, and 50.

Figure 42-4: The Stretch value can elongate flames.

The Regularity value determines how much of the Atmospheric Apparatus is filled. The spherical gizmos in the previous figures were all set to 0.2, so the entire sphere shape wasn’t filled. A setting of 1.0 adds a spherical look to the Fire effect, because the entire gizmo is filled. For a more random shape, use a small Regularity value.

The Flame Size value affects the overall size of each individual flame (though this is dependent on the gizmo size as well). The Flame Detail value controls the edge sharpness of each flame and can range from 1 to 10. Lower values produce fuzzy, smooth flames, but higher values result in sharper, more distinct flames.

The Density value determines the thickness of each flame in its center; higher Density values result in flames that are brighter at the center, while lower values produce thinner, wispy flames. Figure 42-5 shows the difference caused by Density values of, from left to right, 10, 20, 50, and 100.

Figure 42-5: The Fire effect brightness is tied closely to the flame Density value.

The Samples value sets the rate at which the effect is sampled. Higher sample values are required for more detail, but they increase the render time.

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The Motion section includes options for setting the Phase and Drift of a fire effect. The Phase value determines how wildly the fire burns. For a wild, out-of-control fire, animate the Phase value to change rapidly. For a constant, steady fire, keep the value constant throughout the frames. The Drift value sets the height of the flames. High Drift values produce high, hotburning flames.

The Explosion section lets you make a fire into an explosion. When the Explosion check box is selected, the fire is set to explode. The Start and End Times for the explosion are set in the Setup Explosion Phase Curve dialog box that opens when the Setup Explosion button is clicked. If the Smoke option is checked, then the fire colors change to the smoke color for Phase values between 100 and 200. The Fury value varies the churning of the flames. Values greater than 1.0 cause faster churning, and values lower than 1.0 cause slower churning.

Tutorial: Creating the sun

You can use the Fire effect to create a realistic sun. The modeling part is easy — all it requires is a simple sphere — but the real effects come from the materials and the Fire effect.

To create a sun, follow these steps:

1.Open the Sun.max file from the Chap 42 directory on the CD-ROM.

This file contains a simple sphere with a bright yellow material applied to it.

2.Select Create Helpers Atmospherics Sphere Gizmo and drag a sphere in the Front viewport that encompasses the “sun” sphere.

3.With the SphereGizmo still selected, open the Modify panel and click the Add button in the Atmospheres rollout. Select Fire Effect from the Add Atmospheres & Effects dialog box, and click OK. Then select the Fire effect, and click the Setup button.

The Environment and Effects dialog box opens.

4.In the Fire Effects Parameters rollout, set the Inner Color to yellow, the Outer Color to red, and the Smoke color to black (these are the default colors). For the Flame Type, select Tendril with Stretch and Regularity values of 1. Set the Flame Size to 30, the Density to 15, the Flame Detail to 10, and the Samples to 15.

Figure 42-6 shows the resulting sun after it’s been rendered.

Tutorial: Creating clouds

Sky images are fairly easy to find, or you can just take your camera outside and capture your own. The trick comes when you are trying to weave an object in and out of clouds. Although you can do this with a Shadow/Matte mask, it would be easier if the clouds were actual 3D objects. In this tutorial, we create some simple clouds using the Fire effect.

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Figure 42-6: A sun image created with a simple sphere, a material with a Noise Bump map, and the Fire effect.

To create some clouds for a sky backdrop, follow these steps:

1.Open the Clouds.max file from the Chap 42 directory on the CD-ROM.

This file includes several hemispherical-shaped atmospheric apparatus gizmos.

2.Choose Rendering Environment (or press the 8 key) to open the Environment and Effects dialog box. Click the Background Color swatch, and select a light blue color. In the Atmosphere section, click the Add button, select Fire Effect from the Add Atmospheric Effect list, and click OK.

3.Name the effect Clouds, and click each of the color swatches. Change the Inner Color to a dark gray, the Outer Color to a light gray, and the Smoke Color to white. Set the Shape to Fireball with a Stretch of 1 and a Regularity of 0.2. Set the Flame Size to 35, the Flame Detail to 3, the Density to 15, and the Samples to 15.

Tip	If you want to add some motion to the clouds, click the Animate button, drag the Time Slider
	to the last frame, and change the Phase value to 45 and the Drift value to 30. The clouds
	slowly drift through the sky. Disable the Animate button when you’re finished.

4.In the Fire Effect Parameters rollout, click the Pick Gizmo button and then click one of the gizmos in the viewports. Repeat this step until you’ve selected all the gizmos.

Figure 42-7 shows the resulting sky backdrop. By altering the Fire parameters, you can create different types of clouds.