Hi James,
On 18/06/15 15:19, James Lynes wrote:
SetBitmap works, as in:
   $frame->{bmp} = Wx::Bitmap->new("dwf.png", wxBITMAP_TYPE_PNG);
   $frame->{sbm}->SetBitmap($frame->{bmp});
Where $frame->{sbm} is a Static Bitmap.
Ok, mine works too, I don quite know why the demo doesn't. I write all
over my bitmap and refresh it all the time.
When I create a new bitmap assigned to $frame->{sbm}, is the system
reclaiming the memory used by the old bitmap?
I don't know about this, but it would be a property of the wxWidgets
c-code, so it would be a question for their mailing list. To avoid
issues whenever I scale an image for something, I save a copy of the
scaled image which I then use as the source next time. Scaled images
use up very little disc space compared to videos and so on.
I saw in the wxWidgets docs that there is a Bitmap method
newFromPNGData that appears to not be wrapped. This would be useful if
it would bypass the need to write/read to/from disk everytime the PNG
file changes.
In the absence of this being wrapped, you can just use Wx::Image and
it's methods of you can Select it into a device context (eg
Wx::MemoryDC) like this:
my $mdc = Wx::MemoryDC->new();
$mdc->SelectObject($frame->{bmp}); # Having stored your
bitmap from before
my $pen = Wx::Pen->new( $colourData, 3, wxSOLID);
$mdc->SetPen( $pen );
$mdc->SetBrush( wxTRANSPARENT_BRUSH );
# Determine mouse courdinates
my $x=$event->GetX();
my $y=$event->GetY();
# Draw circle round mouse event
$mdc->DrawCircle( $x, $y, $r );
$mdc->SelectObject(wxNullBitmap); #
deselect the bitmap out of the DC
$frame->{sbmp}->SetBitmap(frame->{bmp});
As you do in your linear panel meter.
Regards
Steve.
