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Motion Blur

The Default Scanline Renderer rollout also offers two different types of motion blur: Object Motion Blur and Image Motion Blur. You can enable either of these using the Apply options.

Object Motion Blur is set in the Properties dialog box for each object. The renderer completes this blur by rendering the object over several frames. The movement of the camera doesn’t affect this type of blur. The Duration value determines how long the object is blurred between frames. The Samples value specifies how many Duration units are sampled. The Duration Subdivision value is the number of copies rendered within each Duration segment. All these values can have a maximum setting of 16. The smoothest blurs occur when the Duration and Samples values are equal.

Image Motion Blur is also set in the Properties dialog box for each object. This type of blur is affected by the movement of the camera and is applied after the image has been rendered. You achieve this blur by smearing the image in proportion to the movement of the various objects. The Duration value determines the time length of the blur between frames. The Apply to Environment Map option lets you apply the blurring effect to the background as well as the objects. The Work with Transparency option blurs transparent objects without affecting their transparent regions. Using this option adds time to the rendering process.

Cross-

Reference

You can add two additional blur effects to a scene: the Blur Render Effect, found in the Rendering Effects dialog box (covered in Chapter 43, “Using Render Elements and Render Effects”) and the Scene Motion Blur effect, available through the Video Post dialog box (covered in Chapter 47, “Using the Video Post Interface”).

Other options

The Auto Reflect/Refract Maps section lets you specify a Rendering Iterations value for reflection maps within the scene. The higher the value, the more objects are included in the reflection computations, and the longer the rendering time.

Color Range Limiting offers two methods for correcting overbrightness caused by applying filters. The Clamp method lowers any value above a relative ceiling of 1 to 1 and raises any values below 0 to 0. The Scale method scales all colors between the maximum and minimum values.

The Conserve Memory option optimizes the rendering process to use the least amount of memory possible. If you plan on using Max (or some other program) while it is rendering, you should enable this option.

Rendering Preferences

In addition to the settings available in the Render Scene dialog box, the Rendering panel in the Preference Settings dialog box includes many global rendering settings. The Preference Settings dialog box can be opened using the Customize Preferences menu command.

Figure 41-9 shows this panel.

The Video Color Check options specify how unsafe video colors are flagged or corrected. The Flag with black option shows the unsafe colors, and the Scale Luma and Scale Saturation options correct them by scaling either the luminance or the saturation until they are in range. You can also choose to check NTSC or PAL formats.

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Figure 41-9: The Rendering panel in the Preference

Settings dialog box lets you set global rendering settings.

Caution

Be aware that the Scale options can discolor some objects.

Output Dithering options can enable or disable dithering of colors. The options include True Color for 24-bit images and Paletted for 8-bit images.

The Field Order options let you select which field is rendered first. Some video devices use even first, and others use odd first. Check your specific device to see which setting is correct.

The Super Black Threshold setting is the level below which black is displayed as Super Black.

The Angle Separation value sets the angle between the Hotspot and Falloff cones of a light. If the Hotspot angle equals the Falloff angle, then alias artifacts will appear.

The Don’t Anti-alias Against Background option should be enabled if you plan on using a rendered object as part of a composite image. The Filter Background option includes the background image in the anti-aliasing calculations. The Use Environment Alpha option combines the background image’s alpha channel with the scene object’s alpha channel.

The Default Ambient Light Color is the darkest color for rendered shadows in the scene. Selecting a color other than black brightens the shadows.

You can set the Output File Sequencing option to list the frames in order if the Nth Serial Numbering option is enabled. If the Nth Serial Numbering option is disabled, the sequence uses the actual frame numbers.

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In the Render Termination Alert section, you can elect to have a beep triggered when a rendering job is finished. The Frequency value changes the pitch of the sound, and the Duration value changes its length. You can also choose to load and play a different sound. The Choose Sound button opens a File dialog box where you can select the sound file to play.

The GBuffer Layers value is the maximum number of graphics buffers to allow during rendering. This value can range between 1 and 1000. The value you can use depends on the memory of your system.

The Multi-threading option enables the renderer to complete different rendering tasks as separate threads. Threads use the available processor cycles more efficiently by subdividing tasks. This option should be enabled, especially if you’re rendering on a multiprocessor computer.

The Bitmap Pager option breaks rendered images into pages with a specified size. This keeps images from becoming so large that they become difficult to work with. Once enabled, you can specify the Page Size, the Bitmap Size Threshold, and the size in KB of the Memory Pool.

Creating VUE Files

One of the default Current Renderer options available in the Assign Renderer rollout of the Common panel is the VUE File Renderer. This renderer creates VUE files. A VUE file is a textbased script for rendering a scene that you can edit using a text editor.

The contents of a VUE file include keywords followed by a list of parameters. These keywords include objects such as “light” and “camera” and commands such as “transform” and “top.” Parameters can include the part name and values separated by commas. Figure 41-10 shows a sample VUE file.

Figure 41-10: A sample VUE file viewed in a text editor

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When the VUE File Renderer is selected, the rollout in the Render Scene dialog box includes only a single Files button for giving the VUE file a name.

Caution	Be sure to use the Files button in the VUE File Renderer rollout and not the Files button in
	the Common Parameters rollout. When a VUE file is rendered, the Rendered Frame Window
	opens, but no image is created.

Using the Rendered Frame Window

The Rendered Frame Window is a temporary window that holds any rendered images. Often when developing a scene, you want to test-render an image to view the shadows or transparency not visible in the viewports. The Rendered Frame Window, shown in Figure 41-11, enables you to view these test renderings without saving any data to the network or hard drive.

Figure 41-11: The Rendered Frame Window displays rendered images without saving them to a file.

This buffer opens when you select the Rendered Frame Window option and click the Render button in the Render Scene dialog box. You can also view images from a local hard drive or a network drive in the Rendered Frame Window using the File View Image File menu command.

To zoom in on the buffer, hold down the Ctrl key and click the buffer. Right-click while holding down the Ctrl key to zoom out. The Shift key enables you to pan the buffer image. You can also use the mouse wheel (if you have a scrolling mouse) to zoom and pan within the frame buffer.

Tip	You can zoom and pan the image while it is rendering.