* DART Trees files (default values are used for eventual missing fields) 
* 
* Case "Exact location + random dimension". 3 fields must be defined:
* SPECIES_ID:	ID of the species (parameters (optical property,...) defined in the Simulation Editor) 
* POS_X:	Position of tree in the X axis mock-up
* POS_Y:	Position of tree in the X axis mock-up
* 
* Case "Exact location + exact dimension". The below fields must be defined:
* SPECIES_ID:	ID of the species (parameters (optical property,...) defined in the Simulation Editor) 
* POS_X:	X coordinate of the tree
* POS_Y:	Y coordinate of the tree
* T_HEI_BELOW:	Trunk height below the crown
* T_HEI_WITHIN:	Trunk height within the crown
* T_DIA_BELOW:	Trunk diameter below the crown
* T_ROT_NUT:	Trunk nutation rotation (°) (Euler angle)
* T_ROT_PRE:	Trunk precession rotation (°) (Euler angle)
* C_TYPE:	Crown type (0 = ellipsoid, 1=ellipsoid composed, 2=cone, 3=trapezoid, 5=cone composed)
* C_HEI: 	Crown heigth
* LAI:	- If the field is ommited: the species LAI is defined in the GUI
*	- If positive: total leaf area of the tree species (m2)
*	- if negative: leaf volume density (m2/m3)
* C_ROT_INT:	Crown intrinsic rotation (°) (Euler angle) 
* C_ROT_NUT:	Crown nutation rotation (°) (Euler angle)
* C_ROT_PRE:	Crown precession rotation (°) (Euler angle) 
* C_GEO_1:	Crown geometry parameters:
* 		- if crown type = ellipsoid or ellipsoid composed: C_GEO_1 = first axis
*		- if crown type = cone or cone composed: C_GEO_1 = bottom radius
*		- if crown type = trapezoid: C_GEO_1 = bottom length
* C_GEO_2:	Crown geometry parameters:
*		- if crown type = ellipsoid or ellipsoid composed: C_GEO_2 = second axis
*		- if crown type = cone or cone composed: C_GEO_2 = top radius
*		- if crown type = trapezoid: C_GEO_2 = bottom width
* C_GEO_3:	Crown geometry parameters: 
*		- if crown type = ellipsoid composed: C_GEO_3 = half heigth of lower ellipsoid
*		- if crown type = cone composed: C_GEO_3 = cylinder heigth
*		- if crown type = trapezoid: C_GEO_3 = top length 
*		- if other crown type: C_GEO_3 is undefined
* C_GEO_4:	Crown geometry parameters:
*		- if crown type = trapezoid: C_GEO_4 = top width
*		- if other crown type: C_GEO_4 is undefined
* 
* First line is the header. It defines the order of input of the parameters (any order is possible)
SPECIES_ID	POS_X	POS_Y	T_HEI_BELOW	T_HEI_WITHIN	T_DIA_BELOW	C_TYPE	C_HEI	C_GEO_1	C_GEO_2
0	8	20	2	6	0.5	0	9	8	8
