Sprites

On PC engines, for the sprites without palette swaps, you can replace any existing sprite with a PNG in Slade. You have to be careful about the colors of the transparent space when using the nightmare flag, as any tranparency that is not black will show up on the sprite. For paletted sprites, you can set the alpha color to black in GIMP or Photoshop. For true-color sprites, you can use a defringing program, such as PNG defringe, to set the background color to black on sprites.

• PNG Defringe (Rust)
• PNG Defringe (MATLAB)

All sprites have corresponding offsets which determine how high and laterally displaced they appear in-game. Using a program like Slade, you can assign offsets to each sprite. Unfortunately other graphical programs will often remove these offsets when editing sprites, thus you will have to restore them in a program like Slade.

For Doom 64 engines in general, sprites and their animated frames are hardcoded, thus you can only replace existing frames unless you modify the source code.

Monster Sprites

Originally monster sprites are 256-color sets of graphics, each with their own palette.

On PC engines, you can replace any of these sprites with non-paletted images, however monsters with palette swaps (zombiemen, imps, marines, and ect) will no longer palette swap to other variants. To remedy this, you will need to generate a global palette for your enemy and all of its PNG graphics must be in that palette. Then you can edit that palette to create the palette-swapped alternate. Slade can convert GIMP palettes into the Doom format.

On N64 engines, all monsters must be paletted to 256 colors in a palette unique to each monster. This palette can be generated in GIMP, in which then Slade will convert it to the Doom format. Using wadutil64 that Doom-formatted palette can then be made into a N64-compatible WAD.

Other Sprites

Unlike the monster sprites, other sprites (decorations, items, and powerups) do not have an external palette. Originally each sprite contains an internal 16-bit palette, although PC engines now support true-color PNGs. These graphics do not have palette swaps. To make N64-compatible (non-monster) sprites, you will need to generate CI4 graphics as described in the main graphics page.