In your code getNormal () U r passing address of an array vector3D[3] .So to fill the values in each row of vector3D[3] you should fill it like this

because u are not a passing a two dimensional array right!

Inside the function when normal is of type float[*][3] which means normal can take more rows of float[3].
when u find the address of normal
normal[0] = first address float[0][3]
normal[1] = first addr + size of (vector3D)
normal[2] = first addr + size of (vector3D) + size of (vector3D)
so u r trying to find the addres of norma[0][3],normal[1][3], normal[2][3].

for eg
The addresses inside the function: 2293552 2293564 2293576
The values inside the function: -10.000000 0.000000 4.000000

when you note down the address values they will have a difference of 12.

out side the function u r accessing a single dimensional array vector3D[3]

and trying to find out the adress of norma[0],normal[1], normal[2].

The addresses returned : 2293552 2293556 2293560
The values returned : -10.000000 -2.000000 2.000000

from this eg you can also see that address of normal[2] = 2293560 & normal[1][3] = 2293564.