EasyLazFreeType Bug?

[Tommi]

This is my example code:

Code: [Select]

unit Unit1;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, Forms, Controls, Graphics, Dialogs, StdCtrls, EasyLazFreeType, TTTypes,  lazfreetype;

type

  { TForm1 }

  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private

  public

  end;

var
  Form1: TForm1;

implementation

{$R *.lfm}

{ TForm1 }

procedure TForm1.Button1Click(Sender: TObject);
var
  aFont: TFreeTypeFont;
  Glyph: TFreeTypeGlyph;
  GlyphIndex: Integer;
  avg:double;
  TextStr:string;
  CharIdx:integer;
  AdvanceMetrics:TT_Glyph_Metrics;
begin
  TextStr:='Ciao Ciao';
  aFont := TFreeTypeFont.Create;
  try
    aFont.Name := '/home/tommaso/tmp/UbuntuSans-Italic[wdth,wght].ttf';
    //Font.Style:=[ftsBold];
    avg:=0;
    for CharIdx := 1 to Length(TextStr) do
    begin
      GlyphIndex := aFont.CharIndex[ord(TextStr[CharIdx])];
      Glyph := aFont.Glyph[GlyphIndex];
      if Assigned(Glyph) then
      begin
        if TT_Get_Glyph_Metrics(Glyph.Data, AdvanceMetrics) = 0 then
        begin
          avg:=avg+AdvanceMetrics.advance*1.8; //(AdvanceMetrics.bbox.yMax-AdvanceMetrics.bbox.yMin);
        end;
        Glyph.Free;
      end;
    end;
  finally
    //aFont.Free;
  end;
end;

end.

It works, but if I uncomment  aFont.Free; it crashes.
Moreover, if I replace TextStr:=  TextStr:='Ciao Ciao'; with TextStr:=  TextStr:='Ciao Ciao;;'; it crashes on Glyph.Free;.

Any idea? Could it a bug of EasyLazFreeType?

Thank you

[wp]

Why do you free the Glyph? You did not create it, it belongs to the font, therefore the font will free it. So, when you free the font it will free all its glyphs - but you already had destroyed them --> crash.

Correct (no memory leak seen by heaptrc):

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. var
3.   aFont: TFreeTypeFont;
4.   Glyph: TFreeTypeGlyph;
5.   GlyphIndex: Integer;
6.   avg:double;
7.   TextStr:string;
8.   CharIdx:integer;
9.   AdvanceMetrics:TT_Glyph_Metrics;
10. begin
11.   TextStr:='Ciao Ciao';
12.   aFont := TFreeTypeFont.Create;
13.   try
14. //    aFont.Name := '/home/tommaso/tmp/UbuntuSans-Italic[wdth,wght].ttf';
15.     aFont.Name := 'c:\Windows\Fonts\Arial.ttf';
16.     //Font.Style:=[ftsBold];
17.     avg:=0;
18.     for CharIdx := 1 to Length(TextStr) do
19.     begin
20.       GlyphIndex := aFont.CharIndex[ord(TextStr[CharIdx])];
21.       Glyph := aFont.Glyph[GlyphIndex];
22.       if Assigned(Glyph) then
23.       begin
24.         if TT_Get_Glyph_Metrics(Glyph.Data, AdvanceMetrics) = 0 then
25.         begin
26.           avg:=avg+AdvanceMetrics.advance*1.8; //(AdvanceMetrics.bbox.yMax-AdvanceMetrics.bbox.yMin);
27.         end;
28.         //Glyph.Free;
29.       end;
30.     end;
31.   finally
32.     aFont.Free;
33.   end;
34. end;

[Tommi]

Ok, now it works.

Thank you