Re: [wxperl-users] DCPaint Widget Question

[Vaughn S. <vau...@in...>]

Mark,

Perl on my end could not locate the method "get_control"; I had to 
modify the lines from:

    my $canvas = $self->get_control('Canvas');
    my $dc = Wx::ClientDC->new( $canvas );
    $canvas->PrepareDC( $dc );

to:

    my $dc = Wx::ClientDC->new( $self );
     $self->PrepareDC( $dc );

Any thoughts as to what could be the problem?  After making the changes 
it all worked fine (thanks!).

Vaughn

----- Original Message ----- 
From: "Mark Dootson" <mar...@zn...>
To: "Vaughn Staples" <vau...@in...>
Cc: <wxp...@li...>
Sent: Tuesday, March 27, 2007 2:22 PM
Subject: Re: [wxperl-users] DCPaint Widget Question


Vaughn Staples wrote:
> Mark,
>
> A new question concerning the canvas.
>
> With the drawing objects now complete, I need to save the canvas data 
> as
> an image file ... such as a BMP, JPG, or GIF.

Hi Vaughn

Procedure below shows the basics. You just have to look up the 
Wx::FileDialog in the docs and in Wx::Demo to see about selecting 
filename / filetype.

Regards

Mark

sub evt_menu_file_save {
    my ($self, $event) = @_;
    $event->Skip(1);    # allow event to be processed by further 
handlers

    # have user select a file name and type
    my $filename = 'c:/testimage.png';
    my $imagetype = wxBITMAP_TYPE_PNG;

    # get the device context we have drawn on
    my $canvas = $self->get_control('Canvas');
    my $dc = Wx::ClientDC->new( $canvas );
    $canvas->PrepareDC( $dc );

    #get the dimensions
    my ( $width, $height )  = $dc->GetSizeWH();

    # create a bitmap to draw on
    my $bmp = Wx::Bitmap->new($width, $height, -1);

    # select it into a memory dc
    my $mdc = Wx::MemoryDC->new();
    $mdc->SelectObject($bmp);

    # copy the source dc to the memory dc
    $mdc->Blit(0,0,$width,$height,$dc,0,0);

    # get our bitmap back by selecting a null bitmap into the memory dc
    $mdc->SelectObject(wxNullBitmap);

    # create image out of bitmap and save
    my $img = Wx::Image->new($bmp);

    # $img->SaveFile($filename , $imagetype);

    # lets scale it just for fun
    my $scaled = $img->Scale(int($width / 2), int($height/2));

    $scaled->SaveFile($filename , $imagetype);
}