random technical notes

Here’s the Vigenere crypto algorithm as suggested by Allan:

function Vigenere(Src, Key : string; Encrypt : boolean) : string;
const
  OrdMinChar : integer = Ord('A');
  OrdMaxChar : integer = Ord('Z');
  IncludeChars : set of char = ['A'..'Z'];
var
  CharRangeCount, i, j, KeyLen, KeyInc, SrcOrd, CryptOrd : integer;
  SrcA : string;
begin
  CharRangeCount := OrdMaxChar - OrdMinChar + 1;
  KeyLen := Length(Key);
  SetLength(SrcA, Length(Src));
  If Encrypt then
  begin
    // transfer only included characters to SrcA for encryption
    j := 1;
    for i := 1 to Length(Src) do
    begin
      if (Src[i] in IncludeChars) then
      begin
        SrcA[j] := Src[i];
        inc(j);
      end;
    end;
    SetLength(SrcA, j - 1);
  end;
  SetLength(Result, Length(SrcA));
  if Encrypt then
  begin
    // Encrypt to Result
    for i := 1 to Length(SrcA) do
    begin
      SrcOrd := Ord(Src[i]) - OrdMinChar;
      KeyInc := Ord(Key[((i - 1 ) mod KeyLen)+ 1]) - OrdMinChar;
      CryptOrd := ((SrcOrd + KeyInc) mod CharRangeCount) + OrdMinChar;
      Result[i] := Char(CryptOrd);
    end;
  end;
  else
  begin
    // Decrypt to Result
    for i := 1 to Length(SrcA) do
    begin
      SrcOrd := Ord(Src[i]) - OrdMinChar;
      KeyInc := Ord(Key[((i - 1 ) mod KeyLen)+ 1]) - OrdMinChar;
      CryptOrd := ((SrcOrd - KeyInc + CharRangeCount)
                   mod CharRangeCount) + OrdMinChar;
      // KeyInc may be larger than SrcOrd
      Result[i] := Char(CryptOrd);
    end;
  end;
end;

class MainWindow : public QMainWindow
{
 Q_OBJECT;
public:
 MainWindow(QWidget *parent = 0) : QMainWindow(parent)
 {
   QSettings settings;
   restoreGeometry(settings.value("mainWindowGeometry").toByteArray());
   // create docs, toolbars, etc...
   restoreState(settings.value("mainWindowState").toByteArray());
 }

 void closeEvent(QCloseEvent *event)
 {
   QSettings settings;
   settings.setValue("mainWindowGeometry", saveGeometry());
   settings.setValue("mainWindowState", saveState());
 }
};

int main(int argc, char *argv[])
{
 QApplication a(argc, argv);
 QCoreApplication::setOrganizationDomain("OrgDomain");
 QCoreApplication::setOrganizationName("OrgName");
 QCoreApplication::setApplicationName("AppName");
 QCoreApplication::setApplicationVersion("1.0.0");

 MainWindow w;
 w.show();

 return a.exec();
}

The above code will save and restore window position, size, toolbar visibility, toolbar docking area, dock states, locations and sizes. It saves using QSettings which will store your settings in a platform correct way.

Source

This add-in for StarUML exports modeled state machine(s) to Qt C++ code.

The add-in can speed up developing state machines when you need to only model a state machine with StarUML and then export it to source code, instead of maintaining the model and code separately.

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