Elma 2/Technical

Levels

How to parse a level byte by byte. Remember little-endianess.

WIP

Polygon objects are oriented so for y, up is negative and down is positive. Line objects are inverted so for y, up is positive and down is negative.

Main .lev Structure

Offset	Type	Bytes	Description
0	char[5]	5	"POT35" for Elma 2 levels
5	int	4	30 if unlocked level, 0 if locked level. Otherwise, assertion error
9	short	2	1 if topology error, 0 if no topology error.
11	int	4	1 if start out facing right (autoturn at level start)
15	char[51]	51	Unused: Level name/description. "Unnamed". Unused but can be hex-edited
66	char[16]	16	LGR name. Unchangeable except by hex edit. Always "default"
82	char[10]	10	Unused: Ground texture name. Unused. Value always overwritten to "texturea" on save. If missing on open, defaults as "ground"
92	char[10]	10	Unused: Sky texture name. Unused. Value always overwritten to "qgrass" on save. If missing on open, defaults as "sky"
102	byte[20]	20	Unused: ? Appears to be useless. Can be hex-edited
122	int	4	Shareware check. Shareware editor always saves this value as 115. Shareware game cannot open any number greater than 120. Full game is probably 135 but to confirm with real game version
126	double	8	Number of polygons + 0.4643643. Maximum 2000.
134	polygon	?	Sequential list of polygons with data. "Raw" data for editor purposes
?	object1	?	Only exists if no topology error, otherwise this object is skipped. "Processed" data for when you actually open a level.
?	byte	1	0x2B
x	To be continued... Work in progress
?	double	8	Number of objects + 0.4643643. Maximum 500.
x	To be continued... Work in progress

Polygon

Orientation: positive y is down. These polygons are edited by the editor. The editor uses this info to generate Line Objects

Polygon structure

Offset	Type	Bytes	Description
0	int	4	Type: 1=Normal, 2=Inactive, 3=Platform, 4=Path, 5=Autogenerated Border Polygon
4	int	4	Path Subtype: Door=1, Elevator=2, Falling=3, Continuous Oneway=4, Continuous Twoway=5
8	int	4	Platform's Platform ID or Path's Path ID: 0-999
12	int	4	Path's Platform ID: 0-999
16	int	4	Path's Speed at top
20	int	4	Path's Speed at bottom
24	int	4	Path's Open delay
28	int	4	Path's Close delay
32	int	4	Path's ReOpen delay
36	int	4	Path's ReClose delay
40	int	4	Path's Initially flag: 1=Up, 0=Down
44	int	4	Path's No of platforms
48	int	4	Override flag: 1=Polygon interacts with biker
52	int	4	Style index
56	int	4	Override flag: 1=Border on
60	int	4	Override flag: 1=Border off
64	int	4	Override flag: 1=Whole polygon border colored
68	int	4	Distance
72	int	4	Probably always 0. Probably not important as not included in Balazs' debug file (0040F1FB)
76	byte[300]	300	Probably just padding
376	int	4	Number of vertices
380	vertex (double * 2)[?]	vertices * 16	X and Y as two doubles.

Object1

Object1

Offset	Type	Bytes	Description
0	int	4	Total number of vertices across all polygons of type 1 + 5 only.
4	byte[72]*n	72*n	LineObject
x	To be continued... Work in progress

Line Object

Orientation: positive y is up. Each line object is used by the game to draw on the screen and to make lines solid/non-solid.

LineObject

Offset	Type	Bytes	Description
0	double	8	a: Vertex's x
8	double	8	b: (-1)*Vertex's y
16	double	8	c: Delta x to reach the next vertex
24	double	8	d: (-1)*Delta y to reach the next vertex
32	double	8	e: Delta x to move one unit towards the next vertex - c/g - 1=sqrt(e^2+f^2)
40	double	8	f: Delta y to move one unit towards the next vertex - d/g - 1=sqrt(e^2+f^2)
48	double	8	g: Line length - sqrt(c^2+d^2)
56	int	4	Texture ID (draws to right of the line)
60	int	4	0 if solid, 1 if cannot touch
64	int	4	Distance (border polygons copy base polygon distance)
68	int	4	Do not draw to the right of the line if = 1 (equivalent to texture id of 0), otherwise draw texture. Not sure if actually used by the default editor but that's what editing this value does

Data

Texture IDs

Many more ids exist - these are just some examples. Would be better to extract all the images somewhere instead of manually verifying numbers.

TextureID

Id	Texture
0	Do not draw
10	Border texture (solid medium-colored beige)
100	Default ground (sandy rocks)
105	Solid dark green