 Reserved variables:
 ~~~~~~~~~~~~~~~~~~
 Coordinates of the point to compute		PX,PY,PZ 
 Coordinates of the modifier			MX,MY
 Radius and Height of the modifier		MR,MH
 Maximum Z value of the terrain			MAXZ
 Minimum Z value of the terrain			MINZ
 Pigreco (3.14 ... )				PI

 New calculated value for PZ			NEWZ

 Reserved keywords:
 ~~~~~~~~~~~~~~~~~
OPCODE		USE			WHAT DOES
------		---			---------
nop		nop			nothing
htl		htl			halt the execution (return TRUE)
abort		abort			halt the execution (return FALSE)

abs		abs dest		dest = absolute_value(dest)
sqr		sqr dest		dest = square(dest)
sqrt		sqrt dest		dest = square_root(dest)
rand		rand dest		dest = [0..1]
inv		inv dest		dest = 1 / dest
opp		opp dest		dest = -dest
sin		sin dest		dest = sin(dest)
cos		cos dest		dest = cos(dest)
acos		acos dest		dest = acos(dest) [dest must be in the range -1..1 ]

mov		mov dest,source		dest = source
add		add dest,source		dest = dest + source
sub		sub dest,source		dest = dest - source
mul		mul dest,source		dest = dest * source
div		div dest,source		dest = dest / source
susq		susq dest,source	dest = square( dest - source )
max		max alfa,beta		alfa = max(alfa,beta)
min		min alfa,beta		alfa = min(alfa,beta)

ex_dist		ex_dist dest,x0,y0,x1,y1	dest = square_root( square(x0-x1) + square(y0-y1) )
ex_dist2	ex_dist2 dest,x0,y0,x1,y1	dest = square(x0-x1) + square(y0-y1)

cmp		cmp dest,source		compare dest with source

jmp		jmp [label]		jump to label
je		je [label]		jump to label if cmp was equal
jl		jl [label]		jump to label if cmp was lesser
jg		jg [label]		jump to label if cmp was greater
jle		jle [label]		jump to label if cmp was equal or lesser
jge		jge [label]		jump to label if cmp was equal or greater

[label]:				defines a label


 EOF.