ecSyntMemo.pas

procedure TCustomSyntaxMemo.CMMouseWheel(var Message: TCMMouseWheel);
begin
  inherited;

  //AT: add handling of Shift+Wheel
  if GetKeyState(VK_SHIFT) < 0 then
    ScrollPosX := ScrollPosX - Message.WheelDelta div 4
  else
    ScrollPosY := ScrollPosY - Message.WheelDelta div 40;

  Message.Result := 1;
  ResetHint;
end;
