Map translator

ZDoom features a map format translator named xlat which allows to convert map elements into their equivalent used internally by ZDoom. For instance, the Doom linedef special 6, W1_Ceiling_fastCrushAndRaise, becomes turned into Ceiling_CrushAndRaiseA (tag, C_NORMAL, C_NORMAL, 10) by xlat. This translation system also handles linedef flags, sector flags and sector effects.

To use a custom map translator, either create a MAPINFO for your map with a translator = <your translator lump> property, or use the -xlat <your translator file> command line parameter.

Example

This makes the Super Secret level easier to reach in Scythe 2, by slowing the speed at which a very tall door closes, giving you more time to reach the super secret exit before it is blocked. Name it map31cheat.txt, for example.

include "xlat/doom.txt"
3 = WALK, Door_Close (tag, D_SLOW/16)

Insert this in scythe2.zip; and use a command line such as zdoom -file scythe2.zip -xlat map31cheat.txt.

Constants

Xlat uses a number of constants to define the standard values used by the Doom, Heretic and Strife specials. These can be useful to know as a reference when wanting to imitate the speed of certain vanilla actions in the parameterized format offered by the Hexen map format and UDMF. The unit for movement is in eighth of map unit per tic, so C_SLOW corresponds to a movement of 35 units per second. The unit for scrolling is in sixty-fourth of map unit per tic.

Ceiling and crusher speed

C_SLOW = 8

C_NORMAL = 16

C_FAST = 32

C_TURBO = 64

Floor speed

F_SLOW = 8

F_NORMAL = 16

F_FAST = 32

F_TURBO = 64

Door speed

D_SLOW = 16

D_NORMAL = 32

D_FAST = 64

D_TURBO = 128

VDOORWAIT = 150

Stair building speed

ST_SLOW = 2

ST_NORMAL = 4

ST_FAST = 16

ST_TURBO = 32

Platform/lift speed

P_SLOW = 8,

P_NORMAL = 16

P_FAST = 32

P_TURBO = 64

PLATWAIT = 105

ELEVATORSPEED = 32

Donut/pillar speed

DORATE = 4

Texture scrollers

SCROLL_UNIT = 64

Format

The syntax used by xlat is somewhat similar to C, but uses a linebreak rather than a semi-colon to end declarations. Constants can be defined through an enum or through the define keyword. Examples:

enum
{
	D_SLOW		= 16,
	D_NORMAL	= 32,
	D_FAST		= 64,
	D_TURBO		= 128
}

define VDOORWAIT	(150)

Actual translation instructions are on this form:

For normal linedefs

<number> = <flags>, <special>(parameters>)

Example:

9 = USE, Floor_Donut (tag, DORATE, DORATE)

For generalized linedefs

[<special>] (<range start>, <range end>)

{

flags = <value>

arg<number> = <value>

}

A value can be given as a range of bitflags corresponding each to the equivalent value. If no value is given, or no value that corresponds to the bitflag provided, then the final value is zero.

Example:

[Generic_Floor] (0x6000, 0x7fff)
{
	flags |= 0x0c20 [0x0020 : MONST]
	arg2 = 0x0018 [0x0000 : F_SLOW,
			0x0008 : F_NORMAL,
			0x0010 : F_FAST,
			0x0018 : F_TURBO]
	arg3 = 0x0380 [0x0300 : 24,
			0x0380 : 32]
	arg4 = 0x0380 [0x0000 : 1,
			0x0080 : 2,
			0x0100 : 3,
			0x0180 : 4,
			0x0200 : 5,
			0x0280 : 6]
	arg5 = 0x0c00 [0x0000 : 0,
			0x0400 : 1,
			0x0800 : 2,
			0x0c00 : 3]
	arg5 |= 0x0060 [0x0020 : 4,
			 0x0040 : 8,
			 0x0060 : 12]
	arg5 |= 0x1000 [0x1000 : 16]
}

For sector effects

sector <number> = <name>

All sector names are actually constants defined as enums in xlat/defines.i.

Example:

sector 1 = dLight_Flicker;
sector 2 = dLight_StrobeFast;
sector 3 = dLight_StrobeSlow;
sector 4 = dLight_Strobe_Hurt;
sector 5 = dDamage_Hellslime;
sector 7 = dDamage_Nukage;
sector 8 = dLight_Glow;
sector 9 = SECRET_MASK nobitmask;

For linedef flags

lineflag <position> = <value>

All values are actually constants defined as enums in xlat/defines.i.

Example:

lineflag 0 = ML_BLOCKING;
lineflag 1 = ML_BLOCKMONSTERS;
lineflag 2 = ML_TWOSIDED;
lineflag 3 = ML_DONTPEGTOP;
lineflag 4 = ML_DONTPEGBOTTOM;