What is the best way to get a set of unmanaged structs to C#.

I have the following structs:
typedef struct
{
unsigned char Angle[4];
unsigned char Rayon[3];
} StructPointPolaire;
//---------------------------------------------------------------------------
typedef struct
{
StructPointPolaire PointPolaire[36];
}StructForme36Points;
...
typedef struct
{
StructForme36Points        Forme36Points;
...//more structs with similar data
char FinFichier[3];
} StructFormatMo1;

StructFormatMo1 is inside an unmanaged c++ class for which I have a
managed wrapper.  The structs are filed in the constructor.

I need to access StructFormatMo1 (and the structs inside of course) in
C#.  I won't be modifying the data and sending back to the c++
objects.

Thank you very much,
John