Resize form and maintain aspect ratio

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Similar question here: Resize Form while keeping aspect ratio

Basically, what I want is to resize form and maintain its aspect ratio, but I want resizing to follow the cursor as well. The answer in the topic above provided solution that is half-satisfactory - it works, but resizing is working 2x slower than it should. When I start to resize the form by X axis, you can see where the cursor is, and what the form size is:

I thought that since it resizes 2x slower, I should omit 0.5 multiplier in the code and it will work, but no dice. Here is the code that I'm using at the moment:

type
  TfrmTable = class(TForm)
    procedure FormCanResize(Sender: TObject; var NewWidth, NewHeight: Integer; var Resize: Boolean);
    procedure FormCreate(Sender: TObject);
  private
    FAspectRatio: Double;
  public
  end;

var
  frmTable: TfrmTable;

implementation

{$R *.dfm}

procedure TfrmTable.FormCreate(Sender: TObject);
begin
  FAspectRatio := Width / Height;
end;

procedure TfrmTable.FormCanResize(Sender: TObject; var NewWidth, NewHeight: Integer; var Resize: Boolean);
begin
  NewHeight := Round(0.50 * (NewHeight + NewWidth / FAspectRatio));
  NewWidth := Round(NewHeight * FAspectRatio);
end;

I've tried another approach, by using something like this:

procedure TfrmTable.FormCanResize(Sender: TObject; var NewWidth, NewHeight: Integer; var Resize: Boolean);
begin
  if NewWidth <> Width then
    NewHeight := Round(NewWidth / FAspectRatio)
  else
    if NewHeight <> Height then
      NewWidth := Round(NewHeight * FAspectRatio);
end;

What this should do? Well, my thinking is that I first check if NewWidth is different than current Width, and if it is, that means user is resizing form by X axis. Then I should set NewHeight to appropriate value. Otherwise, I check if NewHeight is different than current Height, and set NewWidth value to its appropriate value. This also produces weird results, when I drag form by X axis, it seems to work, and as soon as I stop resizing, form returns to its original size - I concluded that once I stop resizing (let mouse button up), FormCanResize() event gets called with old NewHeight value, which then reverts form back to its old size.

Resize form and maintain aspect ratio

4 Answers