Beefy Boxes and Bandwidth Generously Provided by pair Networks
P is for Practical
 
PerlMonks  

Images in Canvas

by Anonymous Monk
on Nov 26, 2008 at 09:19 UTC ( #726044=perlquestion: print w/replies, xml ) Need Help??

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks,
I am trying to add a jpg file to my canvas but of no go. Here is the simple code that i am working with:
use Tk; use strict; my $mw = new MainWindow; $mw->geometry('600x600+110+110'); my $drawing = $mw->Canvas(-width => 500, -height => 500, -background => "white") -> pack; my $xpm = $drawing->createBitmap(0, 0, -bitmap => '@myfile.bmp'); my $xpm = $drawing->createImage(0, 0, -bitmap => '@myfile.jpg'); #$drawing->createOval(100,50,300,250,-fill=>"black"); #$drawing->createRectangle(150,100,250,200,-fill=>"red"); #$drawing->createText(200,275,-text=>"Some text on my drawing!",-ancho +r=>"center"); MainLoop();
Except the Bitmap and the image, i am able to create all other shapes (the lines that are commented) in the Canvas. I am receiving the below error message format error in bitmap dataerror reading bitmap file "myfile.bmp" at C:/Perl/site/lib/Tk.pm line 250.
Am i doing any thing wrong. Please guide me in right direction.

Replies are listed 'Best First'.
Re: Images in Canvas
by Crian (Deacon) on Nov 26, 2008 at 09:41 UTC

    You use my $xpm two times, I think one of that lines should be commented out.

    In different to the createBitmap method you do not need to put a @ in front of the image name when using createImage, if I understand "Mastering Perl/TK" the right way.

    Perhaps try one of the built in bitmaps first, to be shure to have no problems with the bitmap file, e.g. my $xpm = $drawing->createBitmap(0, 0, -bitmap  => 'info');.

    In case of the createImage method, you have to use an object created with the Photo or Bitmap methods.


    I tested a little bit and ending with this, perhaps it is a source for an idea for you:

    #!/usr/bin/perl use strict; use warnings; use Tk; my $mw = new MainWindow; $mw->geometry('600x600+110+110'); my $drawing = $mw->Canvas( -width => 500, -height => 500, -background => 'white', )->pack(); my $xpm = <<'END'; /* XPM */ static char *test[]={ "32 32 11 1", ". c None", "# c #000000", "h c #004000", "g c #004040", "f c #404000", "e c #808080", "i c #a0a0a4", "c c #c0c000", "d c #ffff00", "b c #ffffc0", "a c #ffffff", "................................", "................................", "................................", "................................", ".............#....###...........", "............#a##.#aba##.........", "...........#aaaa#aaaaaa##.......", "..........#aaaa#aaaaaaaba##.....", ".........#aaaa#aaaaaaaaaaab##...", "........#aaba#aaaaaaabaabaaaa##.", ".......#aaba#baaaaa#baaaaaabaaa#", "......#aaaa#aaaaab#a##baaaaaaa#.", ".....#aaba#aacbba#aaaa##baaab#..", "....#bbaa#abaacc#aaaaaaa##aa#...", "...#bbbb#aaabaa#aaabaaaaaa##....", "..#bbbb#bacaaa#aaaaaaaabaaaa##..", ".#bbbb#bbaacc#aacaaaaaaaaaaaba#.", "#ddbb#bbbbba#aaaaccaaaaaaaaaaaa#", "#edddfgcbbbfaacaaaaccaaaaaaaaa#e", ".#hedddfhcfabaaccaaabccaaaaaa#e.", "...##edddhaacbbaaccbaaaccaab#i..", ".....##e#baaaccabaaccbaabaa#i...", "......##bacbaabccbaaaccabb#e....", "......#bbbbccaabbccaaaaab#i.....", ".....#bbbbbbbccabbaccaab#i......", ".....#ebbbbbbbbccbaabba#i.......", "......##ebbbbbbbbccaabhe........", "........##ebbbbbbbbbb#e.........", "..........##ibbbbbbbhe..........", "............##ebbbb#e...........", "..............#hee#i............", "................##i............."}; END my $bitmap = $mw->Pixmap(-data => $xpm); $drawing->createImage(100, 100, -image => $bitmap); MainLoop();
Re: Images in Canvas
by zentara (Archbishop) on Nov 26, 2008 at 14:52 UTC
    Don't confuse bitmaps with .bmp files. Tk bitmaps and xpm files are handled differently from regular images like Bitmap( .bmp), jpgs, pngs, etc. Here is a basic bitmap (Tk terminology) usage:
    #!/usr/bin/perl use Tk; my $mw = MainWindow->new; $mw->geometry('-5-0'); #$mw->overrideredirect(1); my @color = qw/red green/; my $bits = pack("b8"x8, "...11...", "..1111..", ".111111.", "11111111", "11111111", ".111111.", "..1111..", "...11...",); $mw->DefineBitmap('indicator' => 8,8, $bits); my $label = $mw->Label( -bitmap=>'indicator', -bg=>'black', -fg=>'red', )->pack; $mw->repeat(500,sub{$label->configure( -fg=>$color[0]); @color=reverse(@color); }); MainLoop;
    To load any standard image type( bmp gif jpg png) you first load the image into a Photo object, then specify the Photo object in your widget's image option. Don't forget that gif and bmp are the only ones included by default, so you need use Tk::JPEG and use Tk::Png. Here is your basic image on a canvas.
    #!/usr/bin/perl use warnings; use strict; use Tk; use Tk::JPEG; my $file = "zen16.jpg"; my $mw = Tk::MainWindow->new; my $can = $mw->Canvas( -width => 320, -height => 240 )->pack(); # if you are pulling your image from data (inline base64encoded string # you may need to specify -format #my $img = $mw->Photo( -data => $data, -format => 'jpeg' ); my $img = $mw->Photo( -file => $file); $can->createImage( 0, 0, -image => $img, -anchor => 'nw' ); my $red = $can->createRectangle(0, 20, 50, 75, -fill => 'red'); $can->Tk::bind("<Button-1>", [ \&print_xy, Ev('x'), Ev('y') ]); MainLoop(); sub print_xy { # print "@_\n"; my ($canv, $x, $y) = @_; print "(x,y) = ", $canv->canvasx($x), ", ", $canv->canvasy($y), "\n" +; printf "%6.6X\n", $img->get($canv->canvasx($x), $canv->canvasy($y) ) +; }

    I'm not really a human, but I play one on earth Remember How Lucky You Are

Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: perlquestion [id://726044]
Approved by rovf
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others exploiting the Monastery: (9)
As of 2023-02-09 10:01 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    I prefer not to run the latest version of Perl because:







    Results (44 votes). Check out past polls.

    Notices?