Test.pas

program new;

type
  PPInt8 = ^PInt8;
  PInt8 = ^Int8;

function __Find(const Arr, Item: Pointer; const ItemSize, ItemCount: SizeInt): Int32;
  function _CompareMem(const Item1, Item2: PInt8; const ItemSize: SizeInt): Boolean;
  var
    I: SizeInt;
  begin
    Result := True;
    for I := 0 to ItemSize - 1 do
      if (Item1[I]^ <> Item2[I]^) then
        Exit(False);
  end;
var
  Ptr: PInt8 := PPInt8(Arr)^;
  Start: PtrUInt := PtrUInt(Ptr);
begin
  Result := -1;

  while ((PtrUInt(Ptr) - Start) < (ItemSize * ItemCount)) do
  begin
    if (_CompareMem(Ptr, Item, ItemSize)) then
      Exit((PtrUInt(Ptr) - Start) div ItemSize);

    Inc(Ptr, ItemSize);
  end;
end;

var
  P: TPoint := Point(6, 3);
  TPA: array of TPoint := [Point(3, 2), Point(-1, 4), Point(6, 3), Point(4, 2)];

begin
  ClearDebug;
  WriteLn(__Find(@TPA, @P, SizeOf(TPoint), Length(TPA)));
end.