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NAME

Gtk3::ImageView - Image viewer widget for Gtk3

VERSION

9

SYNOPSIS

use Gtk3::ImageView;
Gtk3->init;

$window = Gtk3::Window->new();

$view = Gtk3::ImageView->new;
$view->set_pixbuf($pixbuf, TRUE);
$window->add($view);

$window->show_all;

DESCRIPTION

The Gtk3::ImageView widget allows the user to zoom, pan and select the specified image and provides hooks to allow additional tools, e.g. painter, to be created and used.

Gtk3::ImageView is a Gtk3 port of Gtk2::ImageView.

To discuss Gtk3::ImageView or gtk3-perl, ask questions and flame/praise the authors, join gtk-perl-list@gnome.org at lists.gnome.org.

SUBROUTINES/METHODS

$view->set_pixbuf( $pixbuf, $zoom_to_fit )

Defines the image to view. The optional zoom_to_fit parameter specifies whether to zoom to fit the image or not.

$view->get_pixbuf

Returns the image currently being viewed.

$view->get_pixbuf_size

Returns a hash of containing the size of the current image in width and height keys.

$view->set_zoom($zoom)

Specifies the zoom level.

$view->get_zoom

Returns the current zoom level.

$view->set_zoom_to_fit($zoom_to_fit, $limit)

Specifies whether to zoom to fit or not. If limit is defined, such automatic zoom will not zoom more than it. If the limit is undefined, the previously set limit is used, initially it's unlimited.

$view->zoom_to_box( $box, $additional_factor )

Specifies a box to zoom to, including an additional zoom factor

$view->zoom_to_selection($context_factor)

Zooms to the current selection, plus an addition zoom factor. Shortcut for

$view->zoom_to_box( $view->get_selection, $context_factor );

$view->get_zoom_to_fit

Returns whether the view is currently zoom to fit or not.

$view->zoom_in

Increases the current zoom by zoom-step times (defaults to 2).

$view->zoom_out

Decreases the current zoom by zoom-step times (defaults to 2).

$view->zoom_to_fit

Shortcut for

$view->set_zoom_to_fit(TRUE);

$view->set_fitting( $value )

Shortcut for

$view->set_zoom_to_fit($value, 1);

which means that it won't stretch a small image to a large window. Provided (despite the ambiguous name) for compatibility with Gtk2::ImageView.

$view->set_offset( $x, $y )

Set the current view offset (i.e. pan position).

$view->set_offset

Returns the current view offset (i.e. pan position).

$view->get_viewport

Returns a hash containing the position and size of the current viewport.

$view->set_tool

Set the current tool (i.e. mode) - an object of a subclass of Gtk3::ImageView::Tool.

Here are some known subclasses of it:

  • Gtk3::ImageView::Tool::Dragger allows the image to be dragged when zoomed.

  • Gtk3::ImageView::Tool::Selector allows the user to select a rectangular area of the image.

  • Gtk3::ImageView::Tool::SelectorDragger selects or drags with different mouse buttons.

Don't rely too much on how Tool currently interacts with ImageView.

$view->get_tool

Returns the current tool (i.e. mode).

$view->set_selection($selection)

Set the current selection as a hash of position and size.

$view->get_selection

Returns the current selection as a hash of position and size.

$view->set_resolution_ratio($ratio)

Set the ratio of the resolutions in the x and y directions, allowing images with non-square pixels to be correctly displayed.

$view->get_resolution_ratio

Returns the current resolution ratio.

$view->set_interpolation

The interpolation method to use, from cairo_filter_t type. Possible values are lowercase strings like nearest. To use different interpolation depending on zoom, set it in the zoom-changed signal.

$view->get_interpolation

Returns the current interpolation method.

DIAGNOSTICS

CONFIGURATION AND ENVIRONMENT

DEPENDENCIES

INCOMPATIBILITIES

Porting from Gtk2::ImageView

  • set_from_pixbuf() was renamed to set_pixbuf() and now its second argument means zoom_to_fit() instead of set_fitting().

  • set_fitting(TRUE) used to be the default, now you need to call it explicitly if you want that behavior. However, once it's called, new calls to set_from_pixbuf() won't reset it, see set_zoom_to_fit() for more details..

  • Drag and drop now can be triggered by subscribing to dnd-start signal, and calling $view->drag_begin_with_coordinates() from the handler. drag_source_set() won't work.

  • Gtk2::ImageView::ScrollWin replacement is not yet implemented.

  • set_transp() is now available through CSS instead, e.g. via

    .imageview.transparent {
        background-image: url('checkers.svg');
    }
  • set_interpolation() now accepts cairo_filter_t instead of GdkInterpType.

BUGS AND LIMITATIONS

This should be rewritten on C, and Perl bindings should be provided via Glib Object Introspection.

AUTHOR

Jeffrey Ratcliffe, <jffry@posteo.net>

Alexey Sokolov <sokolov@google.com>

LICENSE AND COPYRIGHT

Copyright (C) 2018--2020 by Jeffrey Ratcliffe

Copyright (C) 2020 by Google LLC

Modelled after the GtkImageView C widget by Björn Lindqvist <bjourne@gmail.com>

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.5 or, at your option, any later version of Perl 5 you may have available.