Ubuntu Manpage: Gtk2::ImageView - General purpose image viewer for Gtk+

Provided by: libgtk2-imageview-perl_0.05-1build3_amd64

NAME

       Gtk2::ImageView -  General purpose image viewer for Gtk+

SYNOPSIS

        use Gtk2::ImageView;
        Gtk2->init;

        $window = Gtk2::Window->new();

        $view = Gtk2::ImageView->new;
        $view->set_pixbuf($pixbuf, TRUE);
        $window->add($view);

        $window->show_all;

DESCRIPTION

       GtkImageView is a full-featured general purpose image viewer widget for GTK.  It provides
       a scrollable, zoomable pane in which a pixbuf can be displayed.

       The Gtk2::ImageView module allows a perl developer to use the GtkImageView Widget.

HIERARCHY

         Glib::Object
         +----Glib::InitiallyUnowned
              +----Gtk2::Object
                   +----Gtk2::Widget
                        +----Gtk2::ImageView

INTERFACES

         Glib::Object::_Unregistered::AtkImplementorIface
         Gtk2::Buildable

METHODS

widget or undef = Gtk2::ImageView->new
Returns a new Gtk2::ImageView with the following default values.

black bg : FALSE
fitting : TRUE
image tool : a Gtk2::ImageView::Tool::Dragger instance
interpolation mode : GDK_INTERP_BILINEAR
offset : (0, 0)
pixbuf : NULL
show cursor: TRUE
show frame : TRUE
transp : GTK_IMAGE_TRANSP_GRID
zoom : 1.0

boolean = $view->get_black_bg
Returns TRUE if the view renders the widget on a black background, otherwise FALSE.

$view->set_black_bg ($black_bg)
• $black_bg (boolean)

If TRUE, the view uses a black background. If FALSE, the view uses the default (normally
gray) background.

The default value is FALSE.

list = $view->get_check_colors
Reads the two colors used to draw transparent parts of images with an alpha channel. Note
that if the transp setting of the view is GTK_IMAGE_TRANSP_BACKGROUND or
GTK_IMAGE_TRANSP_COLOR, then both colors will be equal.

$view->damage_pixels ($rect)
• $rect (Gtk2::Gdk::Rectangle)

Mark the pixels in the rectangle as damaged. That the pixels are damaged means that they
have been modified and that the view must redraw them to ensure that the visible part of
the image corresponds to the pixels in that image. Calling this method emits the
::pixbuf-changed signal.

This method must be used when modifying the image data:

// Drawing something cool in the area 20,20 - 60,60 here...
...
// And force an update
$view->damage_pixels (Gtk2::Gdk::Rectangle->new(20, 20, 40, 40);

If the whole pixbuf has been modified then rect should be NULL to indicate that a total
update is needed.

See also gtk_image_view_set_pixbuf().

view : a Gtk2::ImageView
view : a Gtk2::Gdk::Rectangle in image space coordinates to mark as damaged or NULL, to
mark the whole pixbuf as damaged.

rectangle = $view->get_draw_rect
Get the rectangle in the widget where the pixbuf is painted, or undef if the view is not
allocated or has no pixbuf.

For example, if the widgets allocated size is 100, 100 and the pixbufs size is 50, 50 and
the zoom factor is 1.0, then the pixbuf will be drawn centered on the widget. rect will
then be (25,25)-[50,50].

This method is useful when converting from widget to image or zoom space coordinates.

boolean = $view->get_fitting
Returns TRUE if the view fits the image, FALSE otherwise.

$view->set_fitting ($fitting)
• $fitting (boolean)

Sets whether to fit or not. If TRUE, then the view will adapt the zoom so that the whole
pixbuf is visible.

Setting the fitting causes the widget to immediately repaint itself.

Fitting is by default TRUE.

view : a Gtk2::ImageView
fitting : whether to fit the image or not

rectangle = $view->image_to_widget_rect ($rect_in)
• $rect_in (Gtk2::Gdk::Rectangle)

Converts a rectangle in image space coordinates to widget space coordinates. If the view
is not realized, or if it contains no pixbuf, then the conversion was unsuccessful, FALSE
is returned and rect_out is left unmodified.

Note that this function may return a rectangle that is not visible on the widget.

interptype = $view->get_interpolation
Returns the current interpolation mode of the view.

$view->set_interpolation ($interp)
• $interp (Gtk2::Gdk::InterpType)

Sets the interpolation mode of how the view. GDK_INTERP_HYPER is the slowest, but produces
the best results. GDK_INTERP_NEAREST is the fastest, but provides bad rendering quality.
GDK_INTERP_BILINEAR is a good compromise.

Setting the interpolation mode causes the widget to immidiately repaint itself.

The default interpolation mode is GDK_INTERP_BILINEAR.

view : a Gtk2::ImageView
interp : The Gtk2::Gdk::InterpType to use. One of GDK_INTERP_NEAREST, GDK_INTERP_BILINEAR
and GDK_INTERP_HYPER.

string = Gtk2::ImageView->library_version
Returns the version of the underlying GtkImageView C library

$view->set_offset ($x, $y, $invalidate=FALSE)
• $x (double)

• $y (double)

• $invalidate (boolean)

Sets the offset of where in the image the GtkImageView should begin displaying image data.

The offset is clamped so that it will never cause the GtkImageView to display pixels
outside the pixbuf. Setting this attribute causes the widget to repaint itself if it is
realized.

If invalidate is TRUE, the views entire area will be invalidated instead of redrawn
immidiately. The view is then queued for redraw, which means that additional operations
can be performed on it before it is redrawn.

The difference can sometimes be important like when you are overlaying data and get
flicker or artifacts when setting the offset. If that happens, setting invalidate to TRUE
could fix the problem. See the source code to GtkImageToolSelector for an example.

Normally, invalidate should always be FALSE because it is much faster to repaint
immidately than invalidating.

view : a Gtk2::ImageView
x : X-component of the offset in zoom space coordinates.
y : Y-component of the offset in zoom space coordinates.
invalidate : whether to invalidate the view or redraw immediately, default=FALSE.

pixbuf or undef = $view->get_pixbuf
Returns the pixbuf this view shows.

$view->set_pixbuf ($pixbuf, $reset_fit=TRUE)
• $pixbuf (Gtk2::Gdk::Pixbuf or undef)

• $reset_fit (boolean)

Sets the pixbuf to display, or NULL to not display any pixbuf. Normally, reset_fit should
be TRUE which enables fitting. Which means that, initially, the whole pixbuf will be
shown.

Sometimes, the fit mode should not be reset. For example, if GtkImageView is showing an
animation, it would be bad to reset the fit mode for each new frame. The parameter should
then be FALSE which leaves the fit mode of the view untouched.

This method should not be used if merely the contents of the pixbuf has changed. See
gtk_image_view_damage_pixels() for that.

If reset_fit is TRUE, the zoom-changed signal is emitted, otherwise not. The pixbuf-
changed signal is also emitted.

The default pixbuf is NULL.

view : a Gtk2::ImageView
pixbuf : The pixbuf to display.
reset_fit : Whether to reset fitting or not.

boolean = $view->get_show_cursor
Returns TRUE if the cursor is shown when the mouse is over the widget, otherwise FALSE.

$view->set_show_cursor ($show_cursor)
• $show_cursor (boolean)

Sets whether to show the mouse cursor when the mouse is over the widget or not. Hiding
the cursor is useful when the widget is fullscreened.

The default value is TRUE.

view : a Gtk2::ImageView
show_cursor : whether to show the cursor or not

boolean = $view->get_show_frame
Returns TRUE if a one pixel frame is drawn around the pixbuf, otherwise FALSE.

$view->set_show_frame ($show_frame)
• $show_frame (boolean)

Sets whether to draw a frame around the image or not. When TRUE, a one pixel wide frame is
shown around the image. Setting this attribute causes the widget to immediately repaint
itself.

The default value is TRUE.

tool = $view->get_tool
Returns the currently bound image tool

$view->set_tool ($tool)
• $tool (Gtk2::ImageView::Tool)

Set the image tool to use. If the new tool is the same as the current tool, then nothing
will be done. Otherwise Gtk2::ImageView::Tool::pixbuf_changed() is called so that the tool
has a chance to generate initial data for the pixbuf.

Setting the tool causes the widget to immediately repaint itself.

The default image tool is a Gtk2::ImageView::Tool::Dragger instance. See also
Gtk2::ImageView::Tool.

view : a Gtk2::ImageView
tool : The image tool to use (must not be NULL)

$view->set_transp ($transp, $transp_color=0x000000)
• $transp (Gtk2::ImageView::Transp)

• $transp_color (integer)

Sets how the view should draw transparent parts of images with an alpha channel. If
transp is GTK_IMAGE_TRANSP_COLOR, the specified color will be used. Otherwise the
transp_color argument is ignored. If it is GTK_IMAGE_TRANSP_BACKGROUND, the background
color of the widget will be used. If it is GTK_IMAGE_TRANSP_GRID, then a grid with light
and dark gray boxes will be drawn on the transparent parts.

Calling this method causes the widget to immediately repaint. It also causes the pixbuf-
changed signal to be emitted. This is done so that other widgets (such as GtkImageNav)
will have a chance to render a view of the pixbuf with the new transparency settings.

view : a Gtk2::ImageView
transp : The Gtk2::ImageView::Transp to use when drawing transparent images, default
GTK_IMAGE_TRANSP_GRID.
transp_color : Color to use when drawing transparent images, default 0x000000.

rectangle = $view->get_viewport
Returns a rectangle with the current viewport. If pixbuf is NULL or there is no viewport,
undef is returned.

The current viewport is defined as the rectangle, in zoomspace coordinates as the area of
the loaded pixbuf the Gtk2::ImageView is currently showing.

double = $view->get_zoom
Get the current zoom factor of the view.

$view->zoom_in
Zoom in the view one step. Calling this method causes the widget to immediately repaint
itself.

view : a Gtk2::ImageView

$view->zoom_out
Zoom out the view one step. Calling this method causes the widget to immediately repaint
itself.

view : a Gtk2::ImageView

$view->set_zoom ($zoom)
• $zoom (double)

Sets the zoom of the view.

Fitting is always disabled after this method has run. The zoom-changed signal is
unconditionally emitted.

view : a Gtk2::ImageView
zoom : the new zoom factor

SIGNALS

       set-zoom (Gtk2::ImageView, double)
       zoom-in (Gtk2::ImageView)
       zoom-out (Gtk2::ImageView)
       set-fitting (Gtk2::ImageView, integer)
       scroll (Gtk2::ImageView, Gtk2::ScrollType, Gtk2::ScrollType)
       mouse-wheel-scroll (Gtk2::ImageView, Gtk2::Gdk::ScrollDirection)
       zoom-changed (Gtk2::ImageView)
       pixbuf-changed (Gtk2::ImageView)
       set-scroll-adjustments (Gtk2::ImageView, Gtk2::Adjustment, Gtk2::Adjustment)

ENUMS AND FLAGS

   enum Gtk2::Gdk::InterpType
       •   'nearest' / 'GDK_INTERP_NEAREST'

       •   'tiles' / 'GDK_INTERP_TILES'

       •   'bilinear' / 'GDK_INTERP_BILINEAR'

       •   'hyper' / 'GDK_INTERP_HYPER'

   enum Gtk2::Gdk::ScrollDirection
       •   'up' / 'GDK_SCROLL_UP'

       •   'down' / 'GDK_SCROLL_DOWN'

       •   'left' / 'GDK_SCROLL_LEFT'

       •   'right' / 'GDK_SCROLL_RIGHT'

   enum Gtk2::ImageView::Transp
       •   'color' / 'GTK_IMAGE_TRANSP_COLOR'

       •   'background' / 'GTK_IMAGE_TRANSP_BACKGROUND'

       •   'grid' / 'GTK_IMAGE_TRANSP_GRID'

   enum Gtk2::ScrollType
       •   'none' / 'GTK_SCROLL_NONE'

       •   'jump' / 'GTK_SCROLL_JUMP'

       •   'step-backward' / 'GTK_SCROLL_STEP_BACKWARD'

       •   'step-forward' / 'GTK_SCROLL_STEP_FORWARD'

       •   'page-backward' / 'GTK_SCROLL_PAGE_BACKWARD'

       •   'page-forward' / 'GTK_SCROLL_PAGE_FORWARD'

       •   'step-up' / 'GTK_SCROLL_STEP_UP'

       •   'step-down' / 'GTK_SCROLL_STEP_DOWN'

       •   'page-up' / 'GTK_SCROLL_PAGE_UP'

       •   'page-down' / 'GTK_SCROLL_PAGE_DOWN'

       •   'step-left' / 'GTK_SCROLL_STEP_LEFT'

       •   'step-right' / 'GTK_SCROLL_STEP_RIGHT'

       •   'page-left' / 'GTK_SCROLL_PAGE_LEFT'

       •   'page-right' / 'GTK_SCROLL_PAGE_RIGHT'

       •   'start' / 'GTK_SCROLL_START'

       •   'end' / 'GTK_SCROLL_END'

AUTHOR

       Jeffrey Ratcliffe <Jeffrey dot Ratcliffe at gmail dot com>, with patches from muppet
       <scott at asofyet dot org>, Torsten Schoenfeld <kaffetisch at web dot de> and Emanuele
       Bassi <ebassi at gmail dot com> Kevin Ryde <user42 at zip.com.au>

       The DESCRIPTION section of this page is adapted from the documentation of GtkImageView.

COPYRIGHT AND LICENSE

       Copyright (c) 2007 -- 2008 by Jeffrey Ratcliffe <Jeffrey.Ratcliffe@gmail.com> see AUTHORS
       for complete list of contributors

       This library is free software; you can redistribute it and/or modify it under the terms of
       the GNU Lesser General Public License as published by the Free Software Foundation; either
       version 3 of the License, or (at your option) any later version.

       This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
       without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
       See the GNU Library General Public License for more details.

       You should have received a copy of the GNU Lesser General Public License along with this
       program.  If not, see <http://www.gnu.org/licenses/>.

COPYRIGHT

       Copyright (C) 2007 by Jeffrey Ratcliffe.

       This software is licensed under the GPL-3; see Gtk2::ImageView for a full notice.