imLayer

ubyte[] img_data =
[
    1,2,3,
    4,5,6,

    7,8,9,
    10,11,12,
];

auto info = ElemInfo( DataType.UBYTE, 1 );

ubyte[] d2l0 = [ 1,2,3,4,5,6 ];
ubyte[] d2l1 = [ 7,8,9,10,11,12 ];

ubyte[] d1l0 = [ 1,2,3,7,8,9 ];
ubyte[] d1l1 = [ 4,5,6,10,11,12 ];

ubyte[] d0l0 = [ 1, 4, 7, 10 ];
ubyte[] d0l1 = [ 2, 5, 8, 11 ];

auto img = Image3( [3,2,2], info, img_data );
auto id2l0 = Image2( [3,2], info, d2l0 );
auto id2l1 = Image2( [3,2], info, d2l1 );
auto id1l0 = Image2( [3,2], info, d1l0 );
auto id1l1 = Image2( [3,2], info, d1l1 );
auto id0l0 = Image2( [2,2], info, d0l0 );
auto id0l1 = Image2( [2,2], info, d0l1 );

assert( imLayer(img,2,0) == id2l0 );
assert( imLayer(img,2,1) == id2l1 );

assert( imLayer(img,1,0) == id1l0 );
assert( imLayer(img,1,1) == id1l1 );

assert( imLayer(img,0,0) == id0l0 );
assert( imLayer(img,0,1) == id0l1 );