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<a href="#GnomeCanvasItem.description" class="shortcut">Description</a>
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<a href="#GnomeCanvasItem.object-hierarchy" class="shortcut">Object Hierarchy</a>
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<h2><span class="refentrytitle"><a name="GnomeCanvasItem.top_of_page"></a>GnomeCanvasItem</span></h2>
<p>GnomeCanvasItem — Base class for all canvas items</p>
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<div class="refsynopsisdiv">
<a name="GnomeCanvasItem.synopsis"></a><h2>Synopsis</h2>
<pre class="synopsis">
#include <libgnomecanvas/libgnomecanvas.h>
struct <a class="link" href="GnomeCanvasItem.html#GnomeCanvasItem-struct" title="struct GnomeCanvasItem">GnomeCanvasItem</a>;
struct <a class="link" href="GnomeCanvasItem.html#GnomeCanvasItemClass" title="struct GnomeCanvasItemClass">GnomeCanvasItemClass</a>;
<a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="returnvalue">GnomeCanvasItem</span></a> * <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-new" title="gnome_canvas_item_new ()">gnome_canvas_item_new</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a> *parent</code></em>,
<em class="parameter"><code><a href="../gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code>...</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-construct" title="gnome_canvas_item_construct ()">gnome_canvas_item_construct</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a> *parent</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code><span class="type">va_list</span> args</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-set" title="gnome_canvas_item_set ()">gnome_canvas_item_set</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code>...</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-set-valist" title="gnome_canvas_item_set_valist ()">gnome_canvas_item_set_valist</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code><span class="type">va_list</span> args</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-move" title="gnome_canvas_item_move ()">gnome_canvas_item_move</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> dx</code></em>,
<em class="parameter"><code><span class="type">double</span> dy</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-affine-relative" title="gnome_canvas_item_affine_relative ()">gnome_canvas_item_affine_relative</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <span class="type">double</span> affine[6]</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-affine-absolute" title="gnome_canvas_item_affine_absolute ()">gnome_canvas_item_affine_absolute</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <span class="type">double</span> affine[6]</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-raise" title="gnome_canvas_item_raise ()">gnome_canvas_item_raise</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">int</span> positions</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-lower" title="gnome_canvas_item_lower ()">gnome_canvas_item_lower</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">int</span> positions</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-raise-to-top" title="gnome_canvas_item_raise_to_top ()">gnome_canvas_item_raise_to_top</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-lower-to-bottom" title="gnome_canvas_item_lower_to_bottom ()">gnome_canvas_item_lower_to_bottom</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-show" title="gnome_canvas_item_show ()">gnome_canvas_item_show</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-hide" title="gnome_canvas_item_hide ()">gnome_canvas_item_hide</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);
<span class="returnvalue">int</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-grab" title="gnome_canvas_item_grab ()">gnome_canvas_item_grab</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>unsigned <span class="type">int</span> event_mask</code></em>,
<em class="parameter"><code><a href="../gdk/gdk-Cursors.html#GdkCursor"><span class="type">GdkCursor</span></a> *cursor</code></em>,
<em class="parameter"><code><a href="../glib/glib-Basic-Types.html#guint32"><span class="type">guint32</span></a> etime</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-ungrab" title="gnome_canvas_item_ungrab ()">gnome_canvas_item_ungrab</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><a href="../glib/glib-Basic-Types.html#guint32"><span class="type">guint32</span></a> etime</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-w2i" title="gnome_canvas_item_w2i ()">gnome_canvas_item_w2i</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> *x</code></em>,
<em class="parameter"><code><span class="type">double</span> *y</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-i2w" title="gnome_canvas_item_i2w ()">gnome_canvas_item_i2w</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> *x</code></em>,
<em class="parameter"><code><span class="type">double</span> *y</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-i2w-affine" title="gnome_canvas_item_i2w_affine ()">gnome_canvas_item_i2w_affine</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> affine[6]</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-i2c-affine" title="gnome_canvas_item_i2c_affine ()">gnome_canvas_item_i2c_affine</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> affine[6]</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-reparent" title="gnome_canvas_item_reparent ()">gnome_canvas_item_reparent</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a> *new_group</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-grab-focus" title="gnome_canvas_item_grab_focus ()">gnome_canvas_item_grab_focus</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-get-bounds" title="gnome_canvas_item_get_bounds ()">gnome_canvas_item_get_bounds</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> *x1</code></em>,
<em class="parameter"><code><span class="type">double</span> *y1</code></em>,
<em class="parameter"><code><span class="type">double</span> *x2</code></em>,
<em class="parameter"><code><span class="type">double</span> *y2</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-request-update" title="gnome_canvas_item_request_update ()">gnome_canvas_item_request_update</a> (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);
</pre>
</div>
<div class="refsect1">
<a name="GnomeCanvasItem.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="synopsis">
<a href="../gobject/gobject-The-Base-Object-Type.html#GObject">GObject</a>
+----<a href="../gobject/gobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a>
+----<a href="../gtk/GtkObject.html">GtkObject</a>
+----GnomeCanvasItem
+----<a class="link" href="GnomeCanvasShape.html" title="GnomeCanvasShape">GnomeCanvasShape</a>
+----<a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup">GnomeCanvasGroup</a>
+----<a class="link" href="GnomeCanvasLine.html" title="GnomeCanvasLine">GnomeCanvasLine</a>
+----<a class="link" href="GnomeCanvasPixbuf.html" title="GnomeCanvasPixbuf">GnomeCanvasPixbuf</a>
+----<a class="link" href="GnomeCanvasRichText.html" title="GnomeCanvasRichText">GnomeCanvasRichText</a>
+----<a class="link" href="libgnomecanvas-gnome-canvas-text.html#GnomeCanvasText">GnomeCanvasText</a>
+----<a class="link" href="GnomeCanvasWidget.html" title="GnomeCanvasWidget">GnomeCanvasWidget</a>
</pre>
</div>
<div class="refsect1">
<a name="GnomeCanvasItem.properties"></a><h2>Properties</h2>
<pre class="synopsis">
"<a class="link" href="GnomeCanvasItem.html#GnomeCanvasItem--parent" title='The "parent" property'>parent</a>" <a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a>* : Read / Write
</pre>
</div>
<div class="refsect1">
<a name="GnomeCanvasItem.signals"></a><h2>Signals</h2>
<pre class="synopsis">
"<a class="link" href="GnomeCanvasItem.html#GnomeCanvasItem-event" title='The "event" signal'>event</a>" : <a href="../gobject/gobject-Signals.html#G-SIGNAL-RUN-LAST:CAPS"><code class="literal">Run Last</code></a>
</pre>
</div>
<div class="refsect1">
<a name="GnomeCanvasItem.description"></a><h2>Description</h2>
<p>
This is the base class for all canvas items. Canvas items are the drawing
elements of a <a class="link" href="GnomeCanvas.html" title="GnomeCanvas"><span class="type">GnomeCanvas</span></a>. Example items include lines,
ellipses, polygons, images, text, curves and even arbitrary GTK+ widgets.
</p>
<p>
Canvas items use the GObject property system to query and set parameters.
Properties are inherited so, for example, a <a class="link" href="GnomeCanvasPolygon.html" title="GnomeCanvasPolygon"><span class="type">GnomeCanvasPolygon</span></a> has
a "fill-color" property that is inherited from its parent class object
<a class="link" href="GnomeCanvasShape.html" title="GnomeCanvasShape"><span class="type">GnomeCanvasShape</span></a>. So be sure to check the parent classes of <a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a>
objects when looking for item properties. More information on GObject
properties can be found in the glib library GObject API reference
documentation.
</p>
<p>
To create a new canvas item call <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-new" title="gnome_canvas_item_new ()"><code class="function">gnome_canvas_item_new()</code></a> which takes a
parent <a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a>, GType of the item to create, and a NULL terminated
list of name/value GObject properties to set for the new item.
</p>
<p>
To change an existing canvas item's properties call <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-set" title="gnome_canvas_item_set ()"><code class="function">gnome_canvas_item_set()</code></a>,
or <a href="../gobject/gobject-The-Base-Object-Type.html#g-object-set"><code class="function">g_object_set()</code></a> can also be used.
</p>
<p>
There are several functions to change the drawing stacking order of an item.
Call <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-raise" title="gnome_canvas_item_raise ()"><code class="function">gnome_canvas_item_raise()</code></a> to raise an item a specified number of
positions or <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-lower" title="gnome_canvas_item_lower ()"><code class="function">gnome_canvas_item_lower()</code></a> to lower it. To raise an item to the
top call <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-raise-to-top" title="gnome_canvas_item_raise_to_top ()"><code class="function">gnome_canvas_item_raise_to_top()</code></a>. The
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-lower-to-bottom" title="gnome_canvas_item_lower_to_bottom ()"><code class="function">gnome_canvas_item_lower_to_bottom()</code></a> function will put it at the bottom.
</p>
<p>
To show an item call <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-show" title="gnome_canvas_item_show ()"><code class="function">gnome_canvas_item_show()</code></a>. Note that canvas item's are
shown by default and so do not need to be explicitly shown after creation
(contrary to GTK+ widget behavior). Call <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-hide" title="gnome_canvas_item_hide ()"><code class="function">gnome_canvas_item_hide()</code></a> to hide an
item.
</p>
<p>
To move an item relative to its current position (item coordinates) call
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-move" title="gnome_canvas_item_move ()"><code class="function">gnome_canvas_item_move()</code></a> or <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-affine-relative" title="gnome_canvas_item_affine_relative ()"><code class="function">gnome_canvas_item_affine_relative()</code></a> for more
complex transforms. <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-affine-absolute" title="gnome_canvas_item_affine_absolute ()"><code class="function">gnome_canvas_item_affine_absolute()</code></a> can be used to
set an item's transform to specific values (not offsets).
</p>
<p>
To convert between world and item coordinate systems call
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-w2i" title="gnome_canvas_item_w2i ()"><code class="function">gnome_canvas_item_w2i()</code></a>, and to convert in the other direction call
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-i2w" title="gnome_canvas_item_i2w ()"><code class="function">gnome_canvas_item_i2w()</code></a>. To get the transform for converting from item
to world coordinates use <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-i2w-affine" title="gnome_canvas_item_i2w_affine ()"><code class="function">gnome_canvas_item_i2w_affine()</code></a> or for converting
item to canvas coordinates, <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-i2c-affine" title="gnome_canvas_item_i2c_affine ()"><code class="function">gnome_canvas_item_i2c_affine()</code></a>.
</p>
<p>
Handling user input for interactive items is accomplished through a
few functions and the "event" signal. To grab the mouse cursor call
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-grab" title="gnome_canvas_item_grab ()"><code class="function">gnome_canvas_item_grab()</code></a>, it can be ungrabbed with
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-ungrab" title="gnome_canvas_item_ungrab ()"><code class="function">gnome_canvas_item_ungrab()</code></a> (see <a href="../gdk/gdk-General.html#gdk-pointer-grab"><code class="function">gdk_pointer_grab()</code></a> of the GTK+ library
for details). To grab keyboard focus call
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-grab-focus" title="gnome_canvas_item_grab_focus ()"><code class="function">gnome_canvas_item_grab_focus()</code></a>. Received events will be signaled via
the "event" signal.
</p>
<p>
Some other useful functions include a reparenting routine,
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-reparent" title="gnome_canvas_item_reparent ()"><code class="function">gnome_canvas_item_reparent()</code></a>, and a function to query the bounding
box of an item (a minumum rectangular area containing all parts of the item),
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-get-bounds" title="gnome_canvas_item_get_bounds ()"><code class="function">gnome_canvas_item_get_bounds()</code></a>.
</p>
</div>
<div class="refsect1">
<a name="GnomeCanvasItem.details"></a><h2>Details</h2>
<div class="refsect2">
<a name="GnomeCanvasItem-struct"></a><h3>struct GnomeCanvasItem</h3>
<pre class="programlisting">struct GnomeCanvasItem;</pre>
<p>
This structure should not be accessed directly. Use the object's properties
and functions for querying or changing its parameters.
</p>
</div>
<hr>
<div class="refsect2">
<a name="GnomeCanvasItemClass"></a><h3>struct GnomeCanvasItemClass</h3>
<pre class="programlisting">struct GnomeCanvasItemClass {
GtkObjectClass parent_class;
/* Tell the item to update itself. The flags are from the update flags
* defined above. The item should update its internal state from its
* queued state, and recompute and request its repaint area. The
* affine, if used, is a pointer to a 6-element array of doubles. The
* update method also recomputes the bounding box of the item.
*/
void (* update) (GnomeCanvasItem *item, double *affine, ArtSVP *clip_path, int flags);
/* Realize an item -- create GCs, etc. */
void (* realize) (GnomeCanvasItem *item);
/* Unrealize an item */
void (* unrealize) (GnomeCanvasItem *item);
/* Map an item - normally only need by items with their own GdkWindows */
void (* map) (GnomeCanvasItem *item);
/* Unmap an item */
void (* unmap) (GnomeCanvasItem *item);
/* Return the microtile coverage of the item */
ArtUta *(* coverage) (GnomeCanvasItem *item);
/* Draw an item of this type. (x, y) are the upper-left canvas pixel
* coordinates of the drawable, a temporary pixmap, where things get
* drawn. (width, height) are the dimensions of the drawable.
*/
void (* draw) (GnomeCanvasItem *item, GdkDrawable *drawable,
int x, int y, int width, int height);
/* Render the item over the buffer given. The buf data structure
* contains both a pointer to a packed 24-bit RGB array, and the
* coordinates. This method is only used for antialiased canvases.
*
* TODO: figure out where clip paths fit into the rendering framework.
*/
void (* render) (GnomeCanvasItem *item, GnomeCanvasBuf *buf);
/* Calculate the distance from an item to the specified point. It also
* returns a canvas item which is the item itself in the case of the
* object being an actual leaf item, or a child in case of the object
* being a canvas group. (cx, cy) are the canvas pixel coordinates that
* correspond to the item-relative coordinates (x, y).
*/
double (* point) (GnomeCanvasItem *item, double x, double y, int cx, int cy,
GnomeCanvasItem **actual_item);
/* Fetch the item's bounding box (need not be exactly tight). This
* should be in item-relative coordinates.
*/
void (* bounds) (GnomeCanvasItem *item, double *x1, double *y1, double *x2, double *y2);
/* Signal: an event occurred for an item of this type. The (x, y)
* coordinates are in the canvas world coordinate system.
*/
gboolean (* event) (GnomeCanvasItem *item, GdkEvent *event);
/* Reserved for future expansion */
gpointer spare_vmethods [4];
};
</pre>
<p>
The internals of this class structure are of interest to those creating
objects derived from <a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a>.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><span class="type">GtkObjectClass</span> <em class="structfield"><code><a name="GnomeCanvasItemClass.parent-class"></a>parent_class</code></em>;</span></p></td>
<td>Parent derived class.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.update"></a>update</code></em> ()</span></p></td>
<td>Update method called to tell the item to update itself.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.realize"></a>realize</code></em> ()</span></p></td>
<td>Realize an item (create graphics contexts, etc).</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.unrealize"></a>unrealize</code></em> ()</span></p></td>
<td>Unrealize an item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.map"></a>map</code></em> ()</span></p></td>
<td>Map an item - normally only needed by items with their own GdkWindows.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.unmap"></a>unmap</code></em> ()</span></p></td>
<td>Unmap an item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.coverage"></a>coverage</code></em> ()</span></p></td>
<td>Return the microtile coverage of the item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.draw"></a>draw</code></em> ()</span></p></td>
<td>Draw an item of this type.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.render"></a>render</code></em> ()</span></p></td>
<td>Render the item for anti-aliased canvases.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.point"></a>point</code></em> ()</span></p></td>
<td>Calculate the distance from an item to a point.</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.bounds"></a>bounds</code></em> ()</span></p></td>
<td>Fetch the item's bounding box (rectangular area it occupies).</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code><a name="GnomeCanvasItemClass.event"></a>event</code></em> ()</span></p></td>
<td>The class signal method for the "event" signal.</td>
</tr>
<tr>
<td><p><span class="term"><a href="../glib/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> <em class="structfield"><code><a name="GnomeCanvasItemClass.spare-vmethods"></a>spare_vmethods</code></em>[4];</span></p></td>
<td>Reserved.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-new"></a><h3>gnome_canvas_item_new ()</h3>
<pre class="programlisting"><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="returnvalue">GnomeCanvasItem</span></a> * gnome_canvas_item_new (<em class="parameter"><code><a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a> *parent</code></em>,
<em class="parameter"><code><a href="../gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code>...</code></em>);</pre>
<p>
Creates a new canvas item with <em class="parameter"><code>parent</code></em> as its parent group. The item is
created at the top of its parent's stack, and starts up as visible. The item
is of the specified <em class="parameter"><code>type</code></em>, for example, it can be
<code class="function">gnome_canvas_rect_get_type()</code>. The list of object arguments/value pairs is
used to configure the item. If you need to pass construct time parameters, you
should use <a href="../gobject/gobject-The-Base-Object-Type.html#g-object-new"><code class="function">g_object_new()</code></a> to pass the parameters and
<a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-construct" title="gnome_canvas_item_construct ()"><code class="function">gnome_canvas_item_construct()</code></a> to set up the canvas item.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>parent</code></em> :</span></p></td>
<td>The parent group for the new item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>type</code></em> :</span></p></td>
<td>The object type of the item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>first_arg_name</code></em> :</span></p></td>
<td>A list of object argument name/value pairs, NULL-terminated,
used to configure the item. For example, "fill_color", "black",
"width_units", 5.0, NULL.</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>The newly-created item.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-construct"></a><h3>gnome_canvas_item_construct ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_construct (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a> *parent</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code><span class="type">va_list</span> args</code></em>);</pre>
<p>
Constructs a canvas item; meant for use only by item implementations.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>An unconstructed canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>parent</code></em> :</span></p></td>
<td>The parent group for the item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>first_arg_name</code></em> :</span></p></td>
<td>The name of the first argument for configuring the item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>args</code></em> :</span></p></td>
<td>The list of arguments used to configure the item.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-set"></a><h3>gnome_canvas_item_set ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_set (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code>...</code></em>);</pre>
<p>
Configures a canvas item. The arguments in the item are set to the specified
values, and the item is repainted as appropriate.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>first_arg_name</code></em> :</span></p></td>
<td>The list of object argument name/value pairs used to configure the item.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-set-valist"></a><h3>gnome_canvas_item_set_valist ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_set_valist (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <a href="../glib/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *first_arg_name</code></em>,
<em class="parameter"><code><span class="type">va_list</span> args</code></em>);</pre>
<p>
Configures a canvas item. The arguments in the item are set to the specified
values, and the item is repainted as appropriate.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>first_arg_name</code></em> :</span></p></td>
<td>The name of the first argument used to configure the item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>args</code></em> :</span></p></td>
<td>The list of object argument name/value pairs used to configure the item.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-move"></a><h3>gnome_canvas_item_move ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_move (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> dx</code></em>,
<em class="parameter"><code><span class="type">double</span> dy</code></em>);</pre>
<p>
Moves a canvas item by creating an affine transformation matrix for
translation by using the specified values. This happens in item
local coordinate system, so if you have nontrivial transform, it
most probably does not do, what you want.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>dx</code></em> :</span></p></td>
<td>Horizontal offset.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>dy</code></em> :</span></p></td>
<td>Vertical offset.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-affine-relative"></a><h3>gnome_canvas_item_affine_relative ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_affine_relative (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <span class="type">double</span> affine[6]</code></em>);</pre>
<p>
Combines the specified affine transformation matrix with the item's current
transformation. NULL affine is not allowed.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>affine</code></em> :</span></p></td>
<td>An affine transformation matrix.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-affine-absolute"></a><h3>gnome_canvas_item_affine_absolute ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_affine_absolute (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>const <span class="type">double</span> affine[6]</code></em>);</pre>
<p>
Makes the item's affine transformation matrix be equal to the specified
matrix. NULL affine is treated as identity.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>affine</code></em> :</span></p></td>
<td>An affine transformation matrix.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-raise"></a><h3>gnome_canvas_item_raise ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_raise (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">int</span> positions</code></em>);</pre>
<p>
Raises the item in its parent's stack by the specified number of positions.
If the number of positions is greater than the distance to the top of the
stack, then the item is put at the top.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>positions</code></em> :</span></p></td>
<td>Number of steps to raise the item.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-lower"></a><h3>gnome_canvas_item_lower ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_lower (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">int</span> positions</code></em>);</pre>
<p>
Lowers the item in its parent's stack by the specified number of positions.
If the number of positions is greater than the distance to the bottom of the
stack, then the item is put at the bottom.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>positions</code></em> :</span></p></td>
<td>Number of steps to lower the item.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-raise-to-top"></a><h3>gnome_canvas_item_raise_to_top ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_raise_to_top (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);</pre>
<p>
Raises an item to the top of its parent's stack.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-lower-to-bottom"></a><h3>gnome_canvas_item_lower_to_bottom ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_lower_to_bottom (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);</pre>
<p>
Lowers an item to the bottom of its parent's stack.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-show"></a><h3>gnome_canvas_item_show ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_show (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);</pre>
<p>
Shows a canvas item. If the item was already shown, then no action is taken.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-hide"></a><h3>gnome_canvas_item_hide ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_hide (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);</pre>
<p>
Hides a canvas item. If the item was already hidden, then no action is
taken.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-grab"></a><h3>gnome_canvas_item_grab ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span> gnome_canvas_item_grab (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code>unsigned <span class="type">int</span> event_mask</code></em>,
<em class="parameter"><code><a href="../gdk/gdk-Cursors.html#GdkCursor"><span class="type">GdkCursor</span></a> *cursor</code></em>,
<em class="parameter"><code><a href="../glib/glib-Basic-Types.html#guint32"><span class="type">guint32</span></a> etime</code></em>);</pre>
<p>
Specifies that all events that match the specified event mask should be sent
to the specified item, and also grabs the mouse by calling
<a href="../gdk/gdk-General.html#gdk-pointer-grab"><code class="function">gdk_pointer_grab()</code></a>. The event mask is also used when grabbing the pointer.
If <em class="parameter"><code>cursor</code></em> is not NULL, then that cursor is used while the grab is active.
The <em class="parameter"><code>etime</code></em> parameter is the timestamp required for grabbing the mouse.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>event_mask</code></em> :</span></p></td>
<td>Mask of events that will be sent to this item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>cursor</code></em> :</span></p></td>
<td>If non-NULL, the cursor that will be used while the grab is active.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>etime</code></em> :</span></p></td>
<td>The timestamp required for grabbing the mouse, or GDK_CURRENT_TIME.</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>If an item was already grabbed, it returns <a href="../gdk/gdk-General.html#GDK-GRAB-ALREADY-GRABBED:CAPS"><code class="literal">GDK_GRAB_ALREADY_GRABBED</code></a>. If
the specified item was hidden by calling <a class="link" href="GnomeCanvasItem.html#gnome-canvas-item-hide" title="gnome_canvas_item_hide ()"><code class="function">gnome_canvas_item_hide()</code></a>, then it
returns <a href="../gdk/gdk-General.html#GDK-GRAB-NOT-VIEWABLE:CAPS"><code class="literal">GDK_GRAB_NOT_VIEWABLE</code></a>. Else, it returns the result of calling
<a href="../gdk/gdk-General.html#gdk-pointer-grab"><code class="function">gdk_pointer_grab()</code></a>.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-ungrab"></a><h3>gnome_canvas_item_ungrab ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_ungrab (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><a href="../glib/glib-Basic-Types.html#guint32"><span class="type">guint32</span></a> etime</code></em>);</pre>
<p>
Ungrabs the item, which must have been grabbed in the canvas, and ungrabs the
mouse.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item that holds a grab.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>etime</code></em> :</span></p></td>
<td>The timestamp for ungrabbing the mouse.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-w2i"></a><h3>gnome_canvas_item_w2i ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_w2i (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> *x</code></em>,
<em class="parameter"><code><span class="type">double</span> *y</code></em>);</pre>
<p>
Converts a coordinate pair from world coordinates to item-relative
coordinates.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>X coordinate to convert (input/output value).</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>Y coordinate to convert (input/output value).</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-i2w"></a><h3>gnome_canvas_item_i2w ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_i2w (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> *x</code></em>,
<em class="parameter"><code><span class="type">double</span> *y</code></em>);</pre>
<p>
Converts a coordinate pair from item-relative coordinates to world
coordinates.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>X coordinate to convert (input/output value).</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>Y coordinate to convert (input/output value).</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-i2w-affine"></a><h3>gnome_canvas_item_i2w_affine ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_i2w_affine (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> affine[6]</code></em>);</pre>
<p>
Gets the affine transform that converts from the item's coordinate system to
world coordinates.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>affine</code></em> :</span></p></td>
<td>An affine transformation matrix (return value).</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-i2c-affine"></a><h3>gnome_canvas_item_i2c_affine ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_i2c_affine (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> affine[6]</code></em>);</pre>
<p>
Gets the affine transform that converts from item-relative coordinates to
canvas pixel coordinates.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>affine</code></em> :</span></p></td>
<td>An affine transformation matrix (return value).</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-reparent"></a><h3>gnome_canvas_item_reparent ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_reparent (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a> *new_group</code></em>);</pre>
<p>
Changes the parent of the specified item to be the new group. The item keeps
its group-relative coordinates as for its old parent, so the item may change
its absolute position within the canvas.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>new_group</code></em> :</span></p></td>
<td>A canvas group.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-grab-focus"></a><h3>gnome_canvas_item_grab_focus ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_grab_focus (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);</pre>
<p>
Makes the specified item take the keyboard focus, so all keyboard events will
be sent to it. If the canvas widget itself did not have the focus, it grabs
it as well.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-get-bounds"></a><h3>gnome_canvas_item_get_bounds ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_get_bounds (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>,
<em class="parameter"><code><span class="type">double</span> *x1</code></em>,
<em class="parameter"><code><span class="type">double</span> *y1</code></em>,
<em class="parameter"><code><span class="type">double</span> *x2</code></em>,
<em class="parameter"><code><span class="type">double</span> *y2</code></em>);</pre>
<p>
Queries the bounding box of a canvas item. The bounds are returned in the
coordinate system of the item's parent.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>x1</code></em> :</span></p></td>
<td>Leftmost edge of the bounding box (return value).</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y1</code></em> :</span></p></td>
<td>Upper edge of the bounding box (return value).</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>x2</code></em> :</span></p></td>
<td>Rightmost edge of the bounding box (return value).</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y2</code></em> :</span></p></td>
<td>Lower edge of the bounding box (return value).</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gnome-canvas-item-request-update"></a><h3>gnome_canvas_item_request_update ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gnome_canvas_item_request_update (<em class="parameter"><code><a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *item</code></em>);</pre>
<p>
To be used only by item implementations. Requests that the canvas queue an
update for the specified item.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td>
<td>A canvas item.</td>
</tr></tbody>
</table></div>
</div>
</div>
<div class="refsect1">
<a name="GnomeCanvasItem.property-details"></a><h2>Property Details</h2>
<div class="refsect2">
<a name="GnomeCanvasItem--parent"></a><h3>The <code class="literal">"parent"</code> property</h3>
<pre class="programlisting"> "parent" <a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a>* : Read / Write</pre>
<p>
Parent <a class="link" href="GnomeCanvasGroup.html" title="GnomeCanvasGroup"><span class="type">GnomeCanvasGroup</span></a> that contains the item.
</p>
</div>
</div>
<div class="refsect1">
<a name="GnomeCanvasItem.signal-details"></a><h2>Signal Details</h2>
<div class="refsect2">
<a name="GnomeCanvasItem-event"></a><h3>The <code class="literal">"event"</code> signal</h3>
<pre class="programlisting"><a href="../glib/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> user_function (<a class="link" href="GnomeCanvasItem.html" title="GnomeCanvasItem"><span class="type">GnomeCanvasItem</span></a> *canvasitem,
<a href="../gdk/gdk-Event-Structures.html#GdkEvent"><span class="type">GdkEvent</span></a> *arg1,
<a href="../glib/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data) : <a href="../gobject/gobject-Signals.html#G-SIGNAL-RUN-LAST:CAPS"><code class="literal">Run Last</code></a></pre>
<p>
Signals mouse button clicks, motion, enter/leave, and key press events
on canvas items. Use this signal to create user interactive items.
The <em class="structfield"><code>x</code></em> and <em class="structfield"><code>y</code></em>
coordinates of the <em class="parameter"><code>event</code></em> structure have been converted to canvas world
coordinates.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>canvasitem</code></em> :</span></p></td>
<td>the object which received the signal.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>event</code></em> :</span></p></td>
<td>A GdkEvent structure containing the event that occurred.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td>
<td>user data set when the signal handler was connected.</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>Signal handlers should return <a href="../glib/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> to stop signal emission or <a href="../glib/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a>
to allow other signal handlers to process this event.</td>
</tr>
</tbody>
</table></div>
</div>
</div>
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