AlphaBlend := True ?

[Fred vS]

Hello everybody.
I try to have a transparent form.

Code: [Select]

Form1.AlphaBlendValue := 100; // 0..255
Form1.AlphaBlend := True;

Error:identifier idents no member "AlphaBlend"

I use FPC 2.4.0 in Linux, is it not yet implemented in that version ?

Thanks

[Fred vS]

Re-hello.

In a topic i find :

If you need only some parts transparent then use: TWinControl.SetShape(AShape: TBitmap).

It is exactly what i want.
But how must i do ?
I have image1 with transparent background.
What must be the code if i only want to see the image, without any background. 

Many thanks

[jw]

see
C:\lazarus\examples\shapedcontrols

with this you can make a black and white bitmap as a mask for the shape of your control or form.


search transparent froms for a windows only api to set the form transparent by color

[Fred vS]

@ jw Thanks, the result is exactly what i want but...
The example do not show how to convert a black and  white bitmap into a shape...
How must i do ?
I have 2 images :

- a black and white image1.png (the future shape)
- a other image2.bmp (same shape that black and white image but with colors).

 and then ????
Thanks

[User137]

Load the black and white picture into TBitmap and use TWinControl.SetShape ?

You may have to save the png into bmp for easier loading.

[Fred vS]

OK User137, thanks,   its done (but with png image the program crash, with bmp image, no problem... see picture in attach).

Now i have a other question :
Is it possible to load a picture from  Timage into Tbitmap ?

Many thanks.

[fabienwang]

Yes it is:

With tmpbmp declared as TBitmap,
and Image1 your TImage.

Code: Pascal  [Select][+][-]

1.   tmpbmp := Graphics.TBitmap.Create;
2.   tmpbmp:= Image1.Picture.Bitmap;
3.  

[Fred vS]

Yep FabienWang it does the think 
And big thanks because it opens me a new world.
Normally i stored bitmap into resource, then load it from resource,... lot of work. 
Now i only have to add a image, load picture as you said. And of course image.picture is stored in resource. 
Many, many thanks.


 

[fabienwang]

may i ask you something about the black and white BMP ?
is it 8 bits or something?

Here is my code and it doesn't work:

Code: Pascal  [Select][+][-]

1. procedure TForm1.FormCreate(Sender: TObject);
2. var
3.   tmpbmp: TBitmap;
4. begin
5.   tmpbmp := TBitmap.Create;
6.   tmpbmp.Monochrome := True;
7.   tmpbmp.LoadFromFile('logoa.bmp');
8.   self.SetShape(tmpbmp);
9. end;

or it's not working on GTK2 ?

[Fred vS]

 @Fabian...
Hum, this night i try to use your image.picture > bitmap method :

Code: [Select]

procedure TMiXimumSP.ShapeControl(AControl: TWinControl);
var
  ABitmap: TBitmap;
begin

 ABitmap := Graphics.TBitmap.Create;
 ABitmap := Image2.Picture.Bitmap;  
 
  ABitmap.Monochrome := True;
 ABitmap.Width := form1.Width;
   ABitmap.Height := form1.Height;

  AControl.SetShape(ABitmap);

 end;                  

It is working for Windows but in Linux it crashs...

So, im back to the old method...

Code: [Select]

procedure TMiXimumSP.ShapeControl(AControl: TWinControl);
var
  ABitmap: TBitmap;
  opaths:=strings  ;    

begin
 opaths := Application.Location  ;    
 ABitmap := Graphics.TBitmap.Create;
 {$IFDEF Windows}
 ABitmap.LoadFromFile(opaths +'lib\splash.bmp');
   {$ENDIF}
{$IFDEF UNIX}
  {$IFDEF Darwin}
   ABitmap.LoadFromFile(opaths +'/miximum.app/contents/macos/splash.bmp');

     {$ELSE}

 ABitmap.LoadFromFile(opaths +'/lib/splash.bmp');

      {$ENDIF}
     {$ENDIF}

  ABitmap.Monochrome := True;
 ABitmap.Width := form1.Width;
   ABitmap.Height := form1.Height;

  AControl.SetShape(ABitmap);

  ABitmap.Free;

end;                  

With that code, it is working for all systems...  

[Fred vS]

Re-@Fabian.

It seems to have a bug in image.picture in Linux.
When you load a monochrome picture in Linux, it crash...

That do not appear in Windows.

If you load a monochrome picture in Windows and when you use that same code in Linux, even Lazarus do not load, it crashs even Lazarus....

[JuhaManninen]

It seems to have a bug in image.picture in Linux.
When you load a monochrome picture in Linux, it crash...

That do not appear in Windows.
If you load a monochrome picture in Windows and when you use that same code in Linux, even Lazarus do not load, it crashs even Lazarus....

Could you please create a bug-report with a reproducible test application.

Juha

[Fred vS]

Other bemol for  AControl.SetShape(ABitmap).
It seems that it does not work with Mac OSX carbon (the form is normal, not shaped...).  

The good news is that it works perfectly with Linux and Windows...