1.10. RIX Image File Format.

The RIX File Format is an image format that is used to store the splash screens used when loading both Fallout and Fallout 2. The file format is essentially the Color Rix format, which is a 256 colour format used by RIX Softworks.

The format is a indexed image file format, with the palette information stored with the image. The colour components in the palette use 6 bits per component for a total bit depth of 18 bits per pixel (6 bits for each of red, green, blue).

Offset	Size	Data Type	Description
0x0000	4	string = "RIX3"	Signature used to identify file type.
0x0004	2	unsigned	`WIDTH` : Width of the image.
0x0006	2	unsigned	`HEIGHT` : Height of the image.
0x0008	2		Unknown.
0x000A	256 * 3	unsigned	Palette entries. Here is stored the pixel RGB values for the colours used in the image. Each entry in the palette occupies 3 bytes (1 for each of red, green, blue colour components), and there are 256 elements in the palette. Only the 6 least significant bits contain data. Hence each component needs to be bit shifted to the left 2 bits ( << 2), so that the image is bright enough when displaying. This will result in a bit depth of 24.
0x030A	WIDTH * HEIGHT	unsigned	Image indexes. Here is stored an index into the palette for each pixel in the image. The pixels are stored left to right, then top to bottom on the screen.

Note: All integers are in little endian format.

Created by Noid.