Command & Conquer: Red Alert Vortex Lookup Table

The HOLE####.LUT files found in Command & Conquer: Red Alert, are a set of pixel manipulation lookup tables used to generate the visual effect of the Chrono Vortex, a destructive temporal anomaly that can randomly spawn in the game as a result of the use of the Chronosphere superweapon. The anomaly appears as a whirlpool that slowly moves over the map, and visually distorts anything it moves over.

File format

Each file is a table of 64×64 pixels, without header. Each pixel is comprised of three bytes, with the following meanings:

Data type	Name	Description
BYTE	X	X-coordinate of the pixel to copy from the original screen buffer. Since the tables represent a 64×64 image, these values can only range from 0 to 63.
BYTE	Y	Y-coordinate of the pixel to copy from the original screen buffer. Since the tables represent a 64×64 image, these values can only range from 0 to 63.
BYTE	B	Brightness of the pixel, ranging from 0 to 15. These values are used in combination with the ????_VTX.PAL fading table files to darken the original pixel values, creating a shadow at the inside of the whirlpool effect.

Files list

The files range from HOLE0000.LUT to HOLE0047.LUT, and form three distinct animations:

• 0000-0015: Start of the animation; the vortex hole opens.
• 0016-0031: Main swirling animation; this repeats as long as the vortex exists.
• 0032-0047: End of the animation; the vortex hole flattens out and closes.

In the following images, the pixel manipulations are visualised by representing the X-coordinates as the red colour component of the pixel, the Y coordinates as the blue component, and the darkening effect as the green component. This means the green value is inverted compared to the real data. All values are stretched out over the full 0-255 range for better visibility.

For comparison, the first image shows the blank slate where all X and Y coordinates represent their original locations.

None	Opening	Animating	Closing

The background around the central circle never changes; it maps every pixel coordinate onto itself, without any darkening.

The Chrono Vortex effect in-game

Tools

The following tools are able to work with files in this format.

Name	Platform	View images in this format?	Convert/export to another file/format?	Import from another file/format?	Access hidden data?	Edit metadata?	Notes
Engie File Converter	Windows	Yes	Yes	Yes	N/A	N/A	Produces images as seen above, with X and Y as respectively red and blue colour components, the darkening inverted to show up as green, and the values stretched out over the 0-255 range. This is also the format it requires as input for converting to Vortex LUT files.