IFL Files

An IFL (Image File List) file is an ASCII file that constructs an animation by listing single-frame bitmap files to be used for each rendered frame. When you assign an IFL file as a bitmap, rendering steps through each specified frame, resulting in an animated map.

(In a similar way, if you assign an AVI file or MOV file as a bitmap, rendering steps through each frame of the animation.)

For example, if you assign a 10-frame animation of a blinking red "Danger" sign to a material's diffuse component, apply the material to a cube, and then render a 30-frame animation, the cube displays the blinking red Danger animation three times.

The .ifl file lists the bitmap files to be used with each frame. You can append an optional numeric argument to each file name to specify the number of frames of rendered animation on which it is used. For example:

  ; Anything after a semicolon is a comment, and is ignored.
  sand.tga 20
  pebble.tga 40
  stone.tif 20	
  boulder.tif 20

The IFL file listed above specifies sand.tga to be used for the first 20 frames, pebble.tga to be used for the next 40 frames, stone.tif to be used for 20 frames, and boulder.tif to be used for 20 frames.

Tip: Specify only the file names in your IFL files. The file paths can be derived from the map paths established in your preferences. See External Path Configuration. IFL files with path names can be used only on the system on which you create them.

Sequentially Numbered Files

You can use incrementally numbered bitmap files (for example, frame001.bmp, frame002.bmp, and so on) to construct an IFL file. Either use the IFL Manager Utility, or use the Sequence checkbox in a file selector dialog, as described in the following procedures.

Notes

• If the IFL generator has a name conflict with an existing IFL file, it will increment the new file's name to avoid overwriting the existing file.
• If the IFL generator has any problems with write access while trying to create the IFL file, the process will fail and the IFL file won't be created. Therefore, automatic IFL generation won't work when reading bitmaps from a CD-ROM. You need to copy them to a directory on your hard disk first. Likewise, automatic IFL generation won't work on network drives to which you don't have write access.

Procedures

To construct an IFL file from sequentially numbered files:

1. In the file selector dialog, navigate to a directory that has a sequence of incrementally numbered bitmaps.
2. Choose the name of one of the sequential files (for example, image01.bmp).

   The Sequence checkbox becomes available.

3. Turn on the Sequence checkbox.

   The Setup button becomes available.

4. Click Setup to display the Image File List Control Dialog.
5. In the Image File List Control dialog, choose the options you want, and then click OK.
   Tip: Use the Browse button to set the Target Path to a directory on your hard disk. Do not set this path to a CD-ROM drive, because you cannot save the file there.

   The Image File List (IFL) file is saved to the target directory.

6. In the file selector dialog, click OK.

   This assigns the newly created IFL file as the bitmap.

Example: To select a set of still images as a viewport background:

1. Activate the viewport where you want the animated background.
2. Choose Views menu Viewport Background.
3. In the Background Source group, click Files.

   A Viewport Background dialog is displayed.

4. On Select Background Image dialog, use the Look In field to navigate to the directory containing the files you want to use for the sequence.

   If necessary, change the file type to match the file name extension of the sequence, or choose All Formats.

   Note: The Select Background Image File dialog uses the last location where a bitmap was chosen, rather than the default bitmap path defined in Customize menu Configure User Paths.
5. Construct an IFL file as described in the previous procedure.
6. On the Select Background Image dialog, click OK.

   The IFL file now provides the background for the viewport.

   Tip: The viewport background does not render. To render the IFL file's animation, assign the IFL file as a rendering environment. (See the following procedure.)

To render the frames in an IFL file as a movie (AVI or MOV format):

1. Choose Rendering Environment.
2. On the Environment dialog, click Environment Map.
3. On the Material/Map Browser, choose Bitmap, and then click OK.
4. On the Select Bitmap Image File dialog, choose the IFL file, and then click OK.
5. Click (Time Configuration), and use the Time Configuration dialog to make the animation length match the number of frames specified in the IFL file.
6. Render a viewport to a movie-format file.
   Tip: The aspect ratio of the rendered movie should match the aspect ratio of the frames in the IFL file.