LGR/Technical

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Technical information for Elasto Mania LGR files. Some additional info at Lgrdk.

.LGR File Format

Offset Type Bytes Description
0 char[5] 5 "LGR12" for LGR files. (12 refers to the version of LGR file)
5 int 4 Number of .pcx files contained at the end of the LGR file (x)
9 byte[4] 4 Pictures.lst: identification header: [0xEA, 0x03, 0x00, 0x00] (required to be a valid file)
13 int 4 Pictures.lst: Number of elements in .lst file (l)
17 char[10]*l 10*l Pictures.lst: List of image names, null terminated (e.g. "barrel"+[0,0,0,0]). The maximum name length is 8.
17+10*l int*l 4*l Pictures.lst: Image type (100=picture, 101=texture, 102=mask)
17+14*l int*l 4*l Pictures.lst: Default distance (1-999). (Masks have a distance of 0. QUP_/QDOWN_/qfood have distances of 400 - apparently unused?)
17+18*l int*l 4*l Pictures.lst: Default clipping (0=Unclipped, 1=Ground, 2=Sky)
17+22*l int*l 4*l Pictures.lst: Location of transparent pixel (10=whole image is solid (only valid for masks; throws error for pictures), 11=palette color 0 is the transparent color, 12=topleft, 13=topright, 14=bottomleft, 15=bottomright)
17+26*l Object  ? List of x pcx objects of variable length (see Pcx Object below)
 ? byte[4] 4 End of file marker: [0xE7, 0x05, 0x2E, 0x0B]

Pcx Object

Offset Type Bytes Description
0 char[12] 12 Filename including .pcx, null terminated (e.g. "barrel.pcx"+[0,0] or "plantain.pcx"). Note that after the first [0], there may be garbage characters in old lgrs (e.g. "flag.pcx"+[0,0x10,0x54,0x4C])
12 byte[8] 8 [0x00, 0x95, 0x4C, 0x00, 0x98, 0x95, 0x4C, 0x00]. Only the first byte is important as 0x00 signifies the end of the filename from the previous row. The other bytes are unused.
20 int 4 Length of the .pcx file in bytes (z)
24 byte[z] z Raw contents of original .pcx file

Pictures.lst contents

The format of pictures.lst is described above.

Items excluded from Pictures.lst

All files should be present both as an entry in pictures.lst and as a Pcx Object, except the following, which should only present as Pcx Objects as elastomania handles these files specially:

  • q1body.pcx
  • q1thigh.pcx
  • q1leg.pcx
  • q1bike.pcx
  • q1wheel.pcx
  • q1susp1.pcx
  • q1susp2.pcx
  • q1forarm.pcx
  • q1up_arm.pcx
  • q1head.pcx
  • q2body.pcx
  • q2thigh.pcx
  • q2leg.pcx
  • q2bike.pcx
  • q2wheel.pcx
  • q2susp1.pcx
  • q2susp2.pcx
  • q2forarm.pcx
  • q2up_arm.pcx
  • q2head.pcx
  • qflag.pcx
  • qkiller.pcx
  • qexit.pcx
  • qframe.pcx
  • qcolors.pcx
  • qgrass.pcx

Special filenames included in Pictures.lst

These items are handled specially in elastomania, but must be included in Pictures.lst. While they theoretically have properties such as distance etc., these properties are ignored during lgr loading. Transparency is hardcoded to be the topleft pixel for these files.

  • qup_*.pcx, where * is any text
  • qdown_*.pcx, where * is any text
  • qfoodX.pcx, where X is 1-9

Palette

Palette must be limited to 256 colors. The palette is taken from q1bike.pcx

Mandatory Pcx files for valid .LGR

  • q1body.pcx
  • q1thigh.pcx
  • q1leg.pcx
  • q1bike.pcx
  • q1wheel.pcx
  • q1susp1.pcx
  • q1susp2.pcx
  • q1forarm.pcx
  • q1up_arm.pcx
  • q1head.pcx
  • q2body.pcx
  • q2thigh.pcx
  • q2leg.pcx
  • q2bike.pcx
  • q2wheel.pcx
  • q2susp1.pcx
  • q2susp2.pcx
  • q2forarm.pcx
  • q2up_arm.pcx
  • q2head.pcx
  • qflag.pcx
  • qkiller.pcx
  • qexit.pcx
  • qframe.pcx
  • qcolors.pcx
  • qfood1.pcx

LGR limits

These are the hard-coded limits to LGR files:

Pcx Files

  • There must be 10-3500 Pcx Objects
  • The raw contents of each .pcx file must be between 1-10,000,000 bytes in length
  • The maximum filename length is 8 characters, excluding ".pcx"
  • The filename must end in ".pcx" (or ".spr")

Pictures

  • The maximum number of pictures is 999
  • The maximum picture width is 6000 (does not apply to masks/textures)
  • The maximum picture size (width*height) is 600,000 (e.g. 775*775 is too large) (does not apply to masks/textures) -> further testing reveals that some pictures can be slightly larger than 600,000, but some cannot. I'm not sure what exactly is being counted to 600,000, but all I know is that below 600,000 is for sure safe, whereas most pictures crash above 600,000. Increased zoom will also increase picture size, meaning that if you have very large images in your lgr file, it may not be compatible with increased zoom.
  • There may be no duplicate picture names

Textures

  • There must be 2-99 textures.
  • qgrass.pcx counts as a texture (it is included in the 2-99 limit)
  • There may be no duplicate texture names

Masks

  • The maximum number of masks is 199
  • There exists a "mask is too complicated" error. An example of a mask that is too complicated is a mask alternating every pixel as solid/transparent/solid/transparent of medium size. Increased zoom can also make otherwise acceptable masks throw this error.
  • There may be no duplicate mask names

Grass

  • The maximum number of QUP_* and QDOWN_* .pcx files is 99.

Bike/kuski .pcx files

The following .pcx files are limited to a width of 255 and a height of 255. I think they are all stretched as described in Big_Book_of_Elma_Facts#LGR_tricks.2C_Part_1.

  • q1body.pcx
  • q1thigh.pcx
  • q1leg.pcx
  • q1wheel.pcx
  • q1susp1.pcx
  • q1susp2.pcx
  • q1forarm.pcx
  • q1up_arm.pcx
  • q1head.pcx
  • q2body.pcx
  • q2thigh.pcx
  • q2leg.pcx
  • q2wheel.pcx
  • q2susp1.pcx
  • q2susp2.pcx
  • q2forarm.pcx
  • q2up_arm.pcx
  • q2head.pcx
  • qflag.pcx

Q1bike.pcx and q2bike.pcx are handled specially: Big_Book_of_Elma_Facts#LGR_tricks.2C_Part_1. If the bike image is too small, the bike will simply be invisible or black, but no error will occur.

Object .pcx files

This pertains to qkiller.pcx, qexit.pcx and qfood*.pcx:

  • The width of any object file must be a multiple of 40, as each 40 pixels are used as 1 frame of animation
  • The maximum number of frames is 1000 (however, I think the .pcx file format breaks down before reaching a width of 40,000)
  • If the height of the .pcx file is greater than 40, all the rows past the 40th are ignored and not drawn
  • If the height of the .pcx file is less than 40, the missing rows will be read as garbled data, usually leading to a crash
  • Qfood*.pcx must be entered in order. If a number is missing, no more files will be loaded. (e.g. if qfood 1, 2, and 5 exist, only 1 and 2 will be loaded)

QGRASS.pcx

Qgrass.pcx is added as a hidden texture. It can be used just like any other texture - with masks, or as a ground/sky background image.

getatlatszosag Internal Error

If you have an empty "message.inf" file in your main Elma directory, if you try to open an lgr and get the error message: "getatlatszosag", then the error is caused from a glitch in EasyLGR.exe. When importing images, sometimes the "Background pixel:" option in newly-added images is not set to anything. To fix the bug, make sure all new images have a background pixel option set, even if it is "None"