Graphics2D(3) User Contributed Perl Documentation Graphics2D(3)NAMEPDL::Graphics2D - An object oriented interface to PDL graphics
SYNOPSIS
use PDL::Graphics2D;
$win = PDL::Graphics2D->new(<Interface>, <Options>);
$w = imag2d( $image, 'Title Here', ... );
DESCRIPTION
This is an umbrella class allowing for a simple interface to all
plotting routines in PDL. On its own it does not do any work it merely
passes information to the appropriate class. Ideally this should
probably offer a uniform interface to a variety of packages.
This requires a lot more work before it is useful I feel, but it can be
used already.
CONSTRUCTORS
new
Create a 2-D graphics object with the requested interface type
FUNCTIONS
imag2d
Display a 2-D image in a figure window
imag2d() creates a plain FreeGLUT OpenGL window and displays the input
image with 1:1 aspect ratio for pixels. The window resize is
constrained to the actual ratio of the image dimensions. The initial
display size is currently a 200x200 window to prevent things from being
too small by default.
The image to display can have dimensions ($c,$M,$N) where for $c==4 the
display is in GL_RGBA, for $c==3 the display is GL_RGB, for $c==2 the
display is GL_LUMINANCE_ALPHA, and for $c==1 or for for dimensions
($M,$N) then the display is GL_LUMINANCE.
This routine does not yet thread but multiple images may be viewed at
the same time in separate windows by multiple calls to imag2d(). TriD
graphics visualization windows and the imag2d() windows may be created
and used independently.
NOTE: If you are twiddling a TriD window, the imag2d() windows are
active as well. If you call twiddle() the sub, only the imag2d()
windows will update correctly.
$window_id = imag2d($image, $name, $zoom, $x_off, $y_off);
creates a new image figure window from the input piddle
with the given title, zoom factor, and position (if possible)
$window_id - may be used to refer to the figure window
$image - 2D image piddle with at least 2 or 3 dimensions
e.g. [M,N], [1,M,N], [2,M,N], [3,M,N], [4,M,N]
$name - the name to use for the figure window (optional)
$zoom - desired (float) pixel zoom factor (optional)
($x_off, $y_off) - desired window pixel position (optional)
with (0,0) as the top left pixel of the
display
use PDL::Graphics2D; # imports imag2d() and twiddle()
$a = sequence(64,48,3); # make test RGB image
$a = $a->mv(2,0); # color must be dim(0) with size [0..4]
$a /= $a->max; # pixel values in [0.0,1.0]
$a = sin(10*$a);
$w1 = imag2d($a); # with parens...
$w2 = imag2d $a->sqrt; # or without
$w3 = imag2d $a**2;
imag2d_update
Update an existing imag2d window with new piddle data
$image = random(3,64,48)/2 + 0.25; # random pixel image
$win = imag2d($image); # create original image display
imag2d_update($win, $image->sequence/$image->nelem); # update data
"imag2d_update" allows one to update an "imag2d" display window by
replacing the associated image data with new contents. The new image
data must be the same type and shape as the previous.
Eventually, we would like to implement this via some sort of dataflow
that would be transparent to the user.
twiddle
Enable GUI interaction with a FreeGLUT display window.
twiddle();
Runs the FreeGLUT event loop so window GUI operations
such as resize, expose, mouse click,.. work
perl v5.18.1 2013-05-12 Graphics2D(3)
