The -nostartup command line parameter forces ZDoom to use the text-mode startup log from Doom.
The GAMEINFO lump can be used to override the game default, provided the needed lumps are successfully used.
Heretic displays a 80x25 ANSI text screen called LOADING. It is altered by the executable as such:
- The character in position [49,2] is used to represent the minor version of the executable (e.g., "3" for Heretic 1.3). ZDoom always displays a 3 here. Background and foreground colors are not modified.
- The characters in positions [17,7] to [32,7] are used to display "Loading graphics" in "bright white on cyan background" (3F) characters.
- The characters in positions [17,8] to [32,8] are used to display "Init game engine" in "bright white on cyan background" (3F) characters.
- The characters in positions [17,9] to [45,9] are used to display "Checking network game status." in "bright white on cyan background" (3F) characters.
- The characters in positions [14,14] to [65,14] are used to display the loading bar and are used to display the blocks (█) in "light green on green" characters (AA).
Hexen uses a lump called STARTUP to show a 4-bit, 16-color, 640×480 picture on the startup screen. It is stored in a custom, non-standard format: the first 48 bytes are for the 16 color palette (three bytes per color entry), followed by raw 4-bit planar graphics. The total size is therefore 153648 bytes exactly. The music lump "ORB" is played during loading.
The pixels from [64,441] to [576,464] are used to display the status bar, with hardcoded "notch" graphics. Each time one is drawn, the sound "StartupTick" is played.
The notches can be replaced by raw 4-bit bitmaps. The loading notch is 16×23 (184 bytes) and called NOTCH and the netgame waiting notch is 4×16 (32) and called NETNOTCH. They use the palette defined in STARTUP.
SLADE3 is the only image editing tool currently available that can convert pictures to these formats and create replacement graphics for them.
Strife displays part of a raw 320×200 picture contained in the lump STARTUP0. Only rows 57 to 151 are drawn, 0 to 56 and 152 to 199 are instead filled with color index #240 from the palette (in Strife, it is fully black). To display progress, Strife uses a Sentinel shooting on a Peasant.
- The sentinel is drawn from the STRTBOT lump, a 48×48 picture (2304 byte)
- The peasant is drawn from the STRTPA1, STRTPB1, STRTPC1 and STRTPD1 lumps, each a 32×64 picture (2048 bytes)
- The laser dots that serves as a progress meter are drawn from the STRTLZ1 and STRTLZ2 lumps, each a 16×16 picture (256 bytes)
All these are in raw format and use the PLAYPAL palette.