struct b3Vec3
       x dd 0
       y dd 0
       z dd 0
ends
struct b3Matrix3
       cx b3Vec3
       cy b3Vec3
       cz b3Vec3
ends

struct b3MassData
        ; The shape mass
        mass    dd 0 ;float 

        ; The local center of mass position.
        center  b3Vec3 

        ; The inertia tensor about the shape center of mass.
        inertia b3Matrix3
ends

masssa          b3MassData 10f,0,0,0,1f,0,0,0,1f,0,0,0,1f  ;fasm error: Invalid macro arguments.
    

struc b3Vec3 x,y,z {
       .x dd x
       .y dd y
       .z dd z
}
struc b3Matrix3 x,y,z {
       .cx b3Vec3 x
       .cy b3Vec3 y
       .cz b3Vec3 z
}
struc b3MassData m,c,x,y,z {
        ; The shape mass
        .mass    dd m ;float 

        ; The local center of mass position.
        .center  b3Vec3 c

        ; The inertia tensor about the shape center of mass.
        .inertia b3Matrix3 <x>,<y>,<z>
}

masssa          b3MassData 10f,<0,0,0>,<1f,0,0>,<0,1f,0>,<0,0,1f>      

struct b3Vec3  
       x dd 0
       y dd 0
       z dd 0
ends

struct b3Matrix3 
       cx b3Vec3 
       cy b3Vec3 
       cz b3Vec3 
ends

struc b3MassData m,c,x,y,z {
        ; The shape mass
        .mass    dd m ;float 

        ; The local center of mass position.
        .center  b3Vec3 c

        ; The inertia tensor about the shape center of mass.
        .inertia b3Matrix3 <x>,<y>,<z>
}

masssa          b3MassData 10f,<0,0,0>,<1f,0,0>,<0,1f,0>,<0,0,1f>