I have a PNG that I want to put on an SDL::Surface. Before placing it, it needs to be rotated an arbitrary number of degrees. What I have so far:

sub _make_surface
{
        my $self = shift;

        my $img = Image::Magick->new();
        $img->Read( $self->{sprite} );
        $img->AffineTransform(
                rotate => $self->{move_angle},
        );

        my $img_data = '';
        open( my $sh, '>', \$img_data )
                or die "Can't open filehandle to scalar: $!\n";
        $img->Write(
                file      => $sh,
                filename  => 'img.png',
        );
        close $sh;

        return SDL::Surface->new(
                -from  => $img_data,
        );
}

[download]

The problem is that the resulting image doesn't show up. You just see a single black pixel where the center of the picture is supposed to be.

I'm not stuck on using Image::Magick. GD or any other image processor will work. GD would be nicer because you can get the image data directly (no mucking about with IO::Scalar), but it doesn't appear to have a method for rotating an arbitrary number of degrees. I would prefer to keep everything in memory rather than doing file IO.

"There is no shame in being self-taught, only in not trying to learn in the first place." -- Atrus, Myst: The Book of D'ni.

In reply to Rotating an Image for an SDL::Surface by hardburn

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