I often get Combustion users asking me about the RLA - RPF file created in discreet 3d max... Here is some RPF and RLA background and technical info that I hope you all find informative and useful!
regards,
Jack, denmark
RLA Files: The RLA format is a previously used with SGI computers and popular because RLA supports the ability to include arbitrary image channels. This means that, when you render and specify the RLA file for output, you can set RLA Image File parameters from a specific list. You specify what channels (and what format) you want to write out to the file.
The RLA Image File Format typically has a dialog box with the following options. Sidenote: the MORE info you include within that dialog, that larger the file size gets...
-Standard Channels: The standard channels are RGB color and the alpha (transparency) channel.
-Bits per Channel: Choose either 8 or 16 as the number of bits per channel. Default=8.
-Store Alpha Channel. Choose whether to save the alpha channel.
Default=selected.
When created from Discreets 3ds max, there are additional Optional Channels when you render your RLA files. There are eight additional channels that can be generated and also viewed in the virtual frame buffer:
-Z Depth: Displays Z-Buffer information in repeating gradients from white to black. The gradients indicate relative depth of the object in the scene.
-Material Effects: Displays the Effects Channel used by materials assigned to objects in the scene. The Effects Channel is a material property set in the Material Editor and used during Video Post compositing. Each Effects Channel ID is displayed using a different random color.
-Object: Displays the G-Buffer (p. v3-61 1) Object Channel ID assigned to objects using the Object Properties dialog. The G-Buffer ID is used during Video Post compositing. Each GBuffer ID is displayed using a different random color.
-UV Coordinates: Displays the range of UV mapping coordinates as a color gradient. This channel shows where mapping seams might occur. Note: UV Coordinates will not be displayed on objects that have the UVW Map Modifier applied unless a map has been applied that uses the coordinates.
-Normal: Displays the orientation of normal vectors as a grayscale gradient. Light gray surfaces have normals pointing towards the view. Dark gray surfaces have normals pointing away from the view.
-Non Clamped Color: Displays areas in the image where colors exceeded the valid color range and were corrected by 3ds max. The areas appear as bright saturated colors usually around specular highlights.
-Coverage: This saves the coverage of the surface fragment from which other G-buffer values (Z Depth, Normal, and so on) are obtained. Z-Coverage values range from 0 to 255. To see Z Coverage, render to an RLA file after first checking Z Coverage in the Setup sub-dialog, then choose Z-Coverage in the virtual frame buffer