/* -*- Mode: C; tab-width: 8; indent-tabs-mode: 8; c-basic-offset: 8 -*- */
/*
* Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation
* All rights reserved.
*
* This file is part of the Gnome Library.
*
* The Gnome Library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* The Gnome 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 Library General Public
* License along with the Gnome Library; see the file COPYING.LIB. If not,
* write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/*
@NOTATION@
*/
/*
* GnomeCanvas widget - Tk-like canvas widget for Gnome
*
* GnomeCanvas is basically a port of the Tk toolkit's most excellent canvas
* widget. Tk is copyrighted by the Regents of the University of California,
* Sun Microsystems, and other parties.
*
*
* Authors: Federico Mena <federico@nuclecu.unam.mx>
* Raph Levien <raph@gimp.org>
*/
/*
* TO-DO list for the canvas:
*
* - Allow to specify whether GnomeCanvasImage sizes are in units or pixels
* (scale or don't scale).
*
* - Implement a flag for gnome_canvas_item_reparent() that tells the function
* to keep the item visually in the same place, that is, to keep it in the
* same place with respect to the canvas origin.
*
* - GC put functions for items.
*
* - Widget item (finish it).
*
* - GList *
* gnome_canvas_gimme_all_items_contained_in_this_area (GnomeCanvas *canvas,
* Rectangle area);
*
* - Retrofit all the primitive items with microtile support.
*
* - Curve support for line item.
*
* - Arc item (Havoc has it; to be integrated in GnomeCanvasEllipse).
*
* - Sane font handling API.
*
* - Get_arg methods for items:
* - How to fetch the outline width and know whether it is in pixels or units?
*/
/*
* Raph's TODO list for the antialiased canvas integration:
*
* - ::point() method for text item not accurate when affine transformed.
*
* - Clip rectangle not implemented in aa renderer for text item.
*
* - Clip paths only partially implemented.
*
* - Add more image loading techniques to work around imlib deficiencies.
*/
#include <config.h>
#include <math.h>
#include <string.h>
#include <stdio.h>
#include <gdk/gdkprivate.h>
#include <gtk/gtk.h>
#include "gailcanvas.h"
#include "gnome-canvas.h"
#include "gnome-canvas-i18n.h"
#include "gnome-canvas-util.h"
#include "gnome-canvas-marshal.h"
#include "gnome-canvas-marshal.c"
/* backward-compatibility cruft */
#include "e-util/gtk-compat.h"
/* We must run our idle update handler *before* GDK wants to redraw. */
#define CANVAS_IDLE_PRIORITY (GDK_PRIORITY_REDRAW - 5)
static void gnome_canvas_request_update (GnomeCanvas *canvas);
static void group_add (GnomeCanvasGroup *group,
GnomeCanvasItem *item);
static void group_remove (GnomeCanvasGroup *group,
GnomeCanvasItem *item);
static void add_idle (GnomeCanvas *canvas);
/*** GnomeCanvasItem ***/
/* Some convenience stuff */
#define GCI_UPDATE_MASK \
(GNOME_CANVAS_UPDATE_REQUESTED | \
GNOME_CANVAS_UPDATE_AFFINE | \
GNOME_CANVAS_UPDATE_CLIP | \
GNOME_CANVAS_UPDATE_VISIBILITY)
#define GCI_EPSILON 1e-18
#define GCI_PRINT_MATRIX(s,a) \
g_print ("%s %g %g %g %g %g %g\n", \
s, (a)[0], (a)[1], (a)[2], (a)[3], (a)[4], (a)[5])
enum {
ITEM_PROP_0,
ITEM_PROP_PARENT
};
enum {
ITEM_EVENT,
ITEM_LAST_SIGNAL
};
static void gnome_canvas_item_class_init (GnomeCanvasItemClass *class);
static void gnome_canvas_item_init (GnomeCanvasItem *item);
static gint emit_event (GnomeCanvas *canvas, GdkEvent *event);
static guint item_signals[ITEM_LAST_SIGNAL];
static GObjectClass *item_parent_class;
/**
* gnome_canvas_item_get_type:
*
* Registers the &GnomeCanvasItem class if necessary, and returns the type ID
* associated to it.
*
* Return value: The type ID of the &GnomeCanvasItem class.
**/
GType
gnome_canvas_item_get_type (void)
{
static GType canvas_item_type;
if (!canvas_item_type) {
const GTypeInfo object_info = {
sizeof (GnomeCanvasItemClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) gnome_canvas_item_class_init,
(GClassFinalizeFunc) NULL,
NULL, /* class_data */
sizeof (GnomeCanvasItem),
0, /* n_preallocs */
(GInstanceInitFunc) gnome_canvas_item_init,
NULL /* value_table */
};
canvas_item_type = g_type_register_static (G_TYPE_INITIALLY_UNOWNED, "GnomeCanvasItem",
&object_info, 0);
}
return canvas_item_type;
}
/* Object initialization function for GnomeCanvasItem */
static void
gnome_canvas_item_init (GnomeCanvasItem *item)
{
item->flags |= GNOME_CANVAS_ITEM_VISIBLE;
cairo_matrix_init_identity (&item->matrix);
}
/**
* gnome_canvas_item_new:
* @parent: The parent group for the new item.
* @type: The object type of the item.
* @first_arg_name: 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.
* @Varargs:
*
* Creates a new canvas item with @parent 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 @type, for example, it can be
* gnome_canvas_rect_get_type(). The list of object arguments/value pairs is
* used to configure the item. If you need to pass construct time parameters, you
* should use g_object_new() to pass the parameters and
* gnome_canvas_item_construct() to set up the canvas item.
*
* Return value: The newly-created item.
**/
GnomeCanvasItem *
gnome_canvas_item_new (GnomeCanvasGroup *parent,
GType type,
const gchar *first_arg_name, ...)
{
GnomeCanvasItem *item;
va_list args;
g_return_val_if_fail (GNOME_IS_CANVAS_GROUP (parent), NULL);
g_return_val_if_fail (g_type_is_a (type, gnome_canvas_item_get_type ()), NULL);
item = GNOME_CANVAS_ITEM (g_object_new (type, NULL));
va_start (args, first_arg_name);
gnome_canvas_item_construct (item, parent, first_arg_name, args);
va_end (args);
return item;
}
/* Performs post-creation operations on a canvas item (adding it to its parent
* group, etc.)
*/
static void
item_post_create_setup (GnomeCanvasItem *item)
{
group_add (GNOME_CANVAS_GROUP (item->parent), item);
gnome_canvas_request_redraw (
item->canvas, item->x1, item->y1, item->x2 + 1, item->y2 + 1);
item->canvas->need_repick = TRUE;
}
/* Set_property handler for canvas items */
static void
gnome_canvas_item_set_property (GObject *gobject, guint param_id,
const GValue *value, GParamSpec *pspec)
{
GnomeCanvasItem *item;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (gobject));
item = GNOME_CANVAS_ITEM (gobject);
switch (param_id) {
case ITEM_PROP_PARENT:
if (item->parent != NULL) {
g_warning ("Cannot set `parent' argument after item has "
"already been constructed.");
} else if (g_value_get_object (value)) {
item->parent = GNOME_CANVAS_ITEM (g_value_get_object (value));
item->canvas = item->parent->canvas;
item_post_create_setup (item);
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, param_id, pspec);
break;
}
}
/* Get_property handler for canvas items */
static void
gnome_canvas_item_get_property (GObject *gobject, guint param_id,
GValue *value, GParamSpec *pspec)
{
GnomeCanvasItem *item;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (gobject));
item = GNOME_CANVAS_ITEM (gobject);
switch (param_id) {
case ITEM_PROP_PARENT:
g_value_set_object (value, item->parent);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, param_id, pspec);
break;
}
}
/**
* gnome_canvas_item_construct:
* @item: An unconstructed canvas item.
* @parent: The parent group for the item.
* @first_arg_name: The name of the first argument for configuring the item.
* @args: The list of arguments used to configure the item.
*
* Constructs a canvas item; meant for use only by item implementations.
**/
void
gnome_canvas_item_construct (GnomeCanvasItem *item, GnomeCanvasGroup *parent,
const gchar *first_arg_name, va_list args)
{
g_return_if_fail (GNOME_IS_CANVAS_GROUP (parent));
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
item->parent = GNOME_CANVAS_ITEM (parent);
item->canvas = item->parent->canvas;
g_object_set_valist (G_OBJECT (item), first_arg_name, args);
item_post_create_setup (item);
}
/* If the item is visible, requests a redraw of it. */
static void
redraw_if_visible (GnomeCanvasItem *item)
{
if (item->flags & GNOME_CANVAS_ITEM_VISIBLE)
gnome_canvas_request_redraw (
item->canvas, item->x1, item->y1,
item->x2 + 1, item->y2 + 1);
}
/* Standard object dispose function for canvas items */
static void
gnome_canvas_item_dispose (GObject *object)
{
GnomeCanvasItem *item;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (object));
item = GNOME_CANVAS_ITEM (object);
if (item->canvas)
redraw_if_visible (item);
/* Make the canvas forget about us */
if (item->canvas && item == item->canvas->current_item) {
item->canvas->current_item = NULL;
item->canvas->need_repick = TRUE;
}
if (item->canvas && item == item->canvas->new_current_item) {
item->canvas->new_current_item = NULL;
item->canvas->need_repick = TRUE;
}
if (item->canvas && item == item->canvas->grabbed_item) {
item->canvas->grabbed_item = NULL;
gdk_pointer_ungrab (GDK_CURRENT_TIME);
}
if (item->canvas && item == item->canvas->focused_item)
item->canvas->focused_item = NULL;
/* Normal destroy stuff */
if (item->flags & GNOME_CANVAS_ITEM_MAPPED)
(* GNOME_CANVAS_ITEM_GET_CLASS (item)->unmap) (item);
if (item->flags & GNOME_CANVAS_ITEM_REALIZED)
(* GNOME_CANVAS_ITEM_GET_CLASS (item)->unrealize) (item);
if (item->parent)
group_remove (GNOME_CANVAS_GROUP (item->parent), item);
if (GNOME_CANVAS_ITEM_GET_CLASS (item)->destroy)
GNOME_CANVAS_ITEM_GET_CLASS (item)->destroy (item);
G_OBJECT_CLASS (item_parent_class)->dispose (object);
/* items should remove any reference to item->canvas after the
first ::destroy */
item->canvas = NULL;
}
/* Realize handler for canvas items */
static void
gnome_canvas_item_realize (GnomeCanvasItem *item)
{
item->flags |= GNOME_CANVAS_ITEM_REALIZED;
gnome_canvas_item_request_update (item);
}
/* Unrealize handler for canvas items */
static void
gnome_canvas_item_unrealize (GnomeCanvasItem *item)
{
item->flags &= ~GNOME_CANVAS_ITEM_REALIZED;
}
/* Map handler for canvas items */
static void
gnome_canvas_item_map (GnomeCanvasItem *item)
{
item->flags |= GNOME_CANVAS_ITEM_MAPPED;
}
/* Unmap handler for canvas items */
static void
gnome_canvas_item_unmap (GnomeCanvasItem *item)
{
item->flags &= ~GNOME_CANVAS_ITEM_MAPPED;
}
/* Update handler for canvas items */
static void
gnome_canvas_item_update (GnomeCanvasItem *item,
const cairo_matrix_t *matrix,
gint flags)
{
item->flags &= ~GNOME_CANVAS_ITEM_NEED_UPDATE;
item->flags &= ~GNOME_CANVAS_ITEM_NEED_AFFINE;
item->flags &= ~GNOME_CANVAS_ITEM_NEED_CLIP;
item->flags &= ~GNOME_CANVAS_ITEM_NEED_VIS;
}
/*
* This routine invokes the update method of the item
* Please notice, that we take parent to canvas pixel matrix as argument
* unlike virtual method ::update, whose argument is item 2 canvas pixel
* matrix
*
* I will try to force somewhat meaningful naming for affines (Lauris)
* General naming rule is FROM2TO, where FROM and TO are abbreviations
* So p2cpx is Parent2CanvasPixel and i2cpx is Item2CanvasPixel
* I hope that this helps to keep track of what really happens
*
*/
static void
gnome_canvas_item_invoke_update (GnomeCanvasItem *item,
const cairo_matrix_t *p2c,
gint flags)
{
gint child_flags;
cairo_matrix_t i2c;
child_flags = flags;
if (!(item->flags & GNOME_CANVAS_ITEM_VISIBLE))
child_flags &= ~GNOME_CANVAS_UPDATE_IS_VISIBLE;
/* Calculate actual item transformation matrix */
cairo_matrix_multiply (&i2c, &item->matrix, p2c);
/* apply object flags to child flags */
child_flags &= ~GNOME_CANVAS_UPDATE_REQUESTED;
if (item->flags & GNOME_CANVAS_ITEM_NEED_UPDATE)
child_flags |= GNOME_CANVAS_UPDATE_REQUESTED;
if (item->flags & GNOME_CANVAS_ITEM_NEED_AFFINE)
child_flags |= GNOME_CANVAS_UPDATE_AFFINE;
if (item->flags & GNOME_CANVAS_ITEM_NEED_CLIP)
child_flags |= GNOME_CANVAS_UPDATE_CLIP;
if (item->flags & GNOME_CANVAS_ITEM_NEED_VIS)
child_flags |= GNOME_CANVAS_UPDATE_VISIBILITY;
if (child_flags & GCI_UPDATE_MASK) {
if (GNOME_CANVAS_ITEM_GET_CLASS (item)->update)
GNOME_CANVAS_ITEM_GET_CLASS (item)->update (item, &i2c, child_flags);
}
}
/*
* This routine invokes the point method of the item.
* The arguments x, y should be in the parent item local coordinates.
*
* This is potentially evil, as we are relying on matrix inversion (Lauris)
*/
static GnomeCanvasItem *
gnome_canvas_item_invoke_point (GnomeCanvasItem *item,
gdouble x,
gdouble y,
gint cx,
gint cy)
{
cairo_matrix_t inverse;
/* Calculate x & y in item local coordinates */
inverse = item->matrix;
if (cairo_matrix_invert (&inverse) != CAIRO_STATUS_SUCCESS)
return NULL;
cairo_matrix_transform_point (&inverse, &x, &y);
if (GNOME_CANVAS_ITEM_GET_CLASS (item)->point)
return GNOME_CANVAS_ITEM_GET_CLASS (item)->point (item, x, y, cx, cy);
return NULL;
}
/**
* gnome_canvas_item_set:
* @item: A canvas item.
* @first_arg_name: The list of object argument name/value pairs used to
* configure the item.
* @Varargs:
*
* Configures a canvas item. The arguments in the item are set to the
* specified values, and the item is repainted as appropriate.
**/
void
gnome_canvas_item_set (GnomeCanvasItem *item, const gchar *first_arg_name, ...)
{
va_list args;
va_start (args, first_arg_name);
gnome_canvas_item_set_valist (item, first_arg_name, args);
va_end (args);
}
/**
* gnome_canvas_item_set_valist:
* @item: A canvas item.
* @first_arg_name: The name of the first argument used to configure the item.
* @args: The list of object argument name/value pairs used to configure the item.
*
* Configures a canvas item. The arguments in the item are set to the specified
* values, and the item is repainted as appropriate.
**/
void
gnome_canvas_item_set_valist (GnomeCanvasItem *item,
const gchar *first_arg_name,
va_list args)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_object_set_valist (G_OBJECT (item), first_arg_name, args);
item->canvas->need_repick = TRUE;
}
/**
* gnome_canvas_item_transform:
* @item: A canvas item.
* @matrix: An affine transformation matrix.
*
* Combines the specified affine transformation matrix with the item's current
* transformation.
**/
void
gnome_canvas_item_transform (GnomeCanvasItem *item, const cairo_matrix_t *matrix)
{
cairo_matrix_t i2p;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (matrix != NULL);
/* Calculate actual item transformation matrix */
cairo_matrix_multiply (&i2p, matrix, &item->matrix);
gnome_canvas_item_set_matrix (item, &i2p);
}
/**
* gnome_canvas_item_set_matrix:
* @item: A canvas item.
* @matrix: An affine transformation matrix or %NULL for the identity matrix.
*
* Makes the item's affine transformation matrix be equal to the specified
* matrix. NULL is treated as identity.
**/
void
gnome_canvas_item_set_matrix (GnomeCanvasItem *item, const cairo_matrix_t *matrix)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
if (matrix) {
item->matrix = *matrix;
} else {
cairo_matrix_init_identity (&item->matrix);
}
if (!(item->flags & GNOME_CANVAS_ITEM_NEED_AFFINE)) {
/* Request update */
item->flags |= GNOME_CANVAS_ITEM_NEED_AFFINE;
gnome_canvas_item_request_update (item);
}
item->canvas->need_repick = TRUE;
}
/**
* gnome_canvas_item_move:
* @item: A canvas item.
* @dx: Horizontal offset.
* @dy: Vertical offset.
*
* 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.
**/
void
gnome_canvas_item_move (GnomeCanvasItem *item, gdouble dx, gdouble dy)
{
cairo_matrix_t translate;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
cairo_matrix_init_translate (&translate, dx, dy);
gnome_canvas_item_transform (item, &translate);
}
/* Convenience function to reorder items in a group's child list. This puts the
* specified link after the "before" link. Returns TRUE if the list was changed.
*/
static gboolean
put_item_after (GList *link, GList *before)
{
GnomeCanvasGroup *parent;
GList *old_before, *old_after;
GList *after;
parent = GNOME_CANVAS_GROUP (GNOME_CANVAS_ITEM (link->data)->parent);
if (before)
after = before->next;
else
after = parent->item_list;
if (before == link || after == link)
return FALSE;
/* Unlink */
old_before = link->prev;
old_after = link->next;
if (old_before)
old_before->next = old_after;
else
parent->item_list = old_after;
if (old_after)
old_after->prev = old_before;
else
parent->item_list_end = old_before;
/* Relink */
link->prev = before;
if (before)
before->next = link;
else
parent->item_list = link;
link->next = after;
if (after)
after->prev = link;
else
parent->item_list_end = link;
return TRUE;
}
/**
* gnome_canvas_item_raise:
* @item: A canvas item.
* @positions: Number of steps to raise the item.
*
* 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.
**/
void
gnome_canvas_item_raise (GnomeCanvasItem *item, gint positions)
{
GList *link, *before;
GnomeCanvasGroup *parent;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (positions >= 0);
if (!item->parent || positions == 0)
return;
parent = GNOME_CANVAS_GROUP (item->parent);
link = g_list_find (parent->item_list, item);
g_assert (link != NULL);
for (before = link; positions && before; positions--)
before = before->next;
if (!before)
before = parent->item_list_end;
if (put_item_after (link, before)) {
redraw_if_visible (item);
item->canvas->need_repick = TRUE;
}
}
/**
* gnome_canvas_item_lower:
* @item: A canvas item.
* @positions: Number of steps to lower the item.
*
* 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.
**/
void
gnome_canvas_item_lower (GnomeCanvasItem *item, gint positions)
{
GList *link, *before;
GnomeCanvasGroup *parent;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (positions >= 1);
if (!item->parent || positions == 0)
return;
parent = GNOME_CANVAS_GROUP (item->parent);
link = g_list_find (parent->item_list, item);
g_assert (link != NULL);
if (link->prev)
for (before = link->prev; positions && before; positions--)
before = before->prev;
else
before = NULL;
if (put_item_after (link, before)) {
redraw_if_visible (item);
item->canvas->need_repick = TRUE;
}
}
/**
* gnome_canvas_item_raise_to_top:
* @item: A canvas item.
*
* Raises an item to the top of its parent's stack.
**/
void
gnome_canvas_item_raise_to_top (GnomeCanvasItem *item)
{
GList *link;
GnomeCanvasGroup *parent;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
if (!item->parent)
return;
parent = GNOME_CANVAS_GROUP (item->parent);
link = g_list_find (parent->item_list, item);
g_assert (link != NULL);
if (put_item_after (link, parent->item_list_end)) {
redraw_if_visible (item);
item->canvas->need_repick = TRUE;
}
}
/**
* gnome_canvas_item_lower_to_bottom:
* @item: A canvas item.
*
* Lowers an item to the bottom of its parent's stack.
**/
void
gnome_canvas_item_lower_to_bottom (GnomeCanvasItem *item)
{
GList *link;
GnomeCanvasGroup *parent;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
if (!item->parent)
return;
parent = GNOME_CANVAS_GROUP (item->parent);
link = g_list_find (parent->item_list, item);
g_assert (link != NULL);
if (put_item_after (link, NULL)) {
redraw_if_visible (item);
item->canvas->need_repick = TRUE;
}
}
/**
* gnome_canvas_item_show:
* @item: A canvas item.
*
* Shows a canvas item. If the item was already shown, then no action is taken.
**/
void
gnome_canvas_item_show (GnomeCanvasItem *item)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
if (!(item->flags & GNOME_CANVAS_ITEM_VISIBLE)) {
item->flags |= GNOME_CANVAS_ITEM_VISIBLE;
gnome_canvas_request_redraw (
item->canvas, item->x1, item->y1,
item->x2 + 1, item->y2 + 1);
item->canvas->need_repick = TRUE;
}
}
/**
* gnome_canvas_item_hide:
* @item: A canvas item.
*
* Hides a canvas item. If the item was already hidden, then no action is
* taken.
**/
void
gnome_canvas_item_hide (GnomeCanvasItem *item)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
if (item->flags & GNOME_CANVAS_ITEM_VISIBLE) {
item->flags &= ~GNOME_CANVAS_ITEM_VISIBLE;
gnome_canvas_request_redraw (
item->canvas, item->x1, item->y1,
item->x2 + 1, item->y2 + 1);
item->canvas->need_repick = TRUE;
}
}
/**
* gnome_canvas_item_grab:
* @item: A canvas item.
* @event_mask: Mask of events that will be sent to this item.
* @cursor: If non-NULL, the cursor that will be used while the grab is active.
* @etime: The timestamp required for grabbing the mouse, or GDK_CURRENT_TIME.
*
* Specifies that all events that match the specified event mask should be sent
* to the specified item, and also grabs the mouse by calling
* gdk_pointer_grab(). The event mask is also used when grabbing the pointer.
* If @cursor is not NULL, then that cursor is used while the grab is active.
* The @etime parameter is the timestamp required for grabbing the mouse.
*
* Return value: If an item was already grabbed, it returns
* %GDK_GRAB_ALREADY_GRABBED. If the specified item was hidden by calling
* gnome_canvas_item_hide(), then it returns %GDK_GRAB_NOT_VIEWABLE. Else,
* it returns the result of calling gdk_pointer_grab().
**/
gint
gnome_canvas_item_grab (GnomeCanvasItem *item,
guint event_mask,
GdkCursor *cursor,
guint32 etime)
{
GtkLayout *layout;
GdkWindow *bin_window;
gint retval;
g_return_val_if_fail (
GNOME_IS_CANVAS_ITEM (item), GDK_GRAB_NOT_VIEWABLE);
g_return_val_if_fail (
gtk_widget_get_mapped (GTK_WIDGET (item->canvas)),
GDK_GRAB_NOT_VIEWABLE);
if (item->canvas->grabbed_item)
return GDK_GRAB_ALREADY_GRABBED;
if (!(item->flags & GNOME_CANVAS_ITEM_VISIBLE))
return GDK_GRAB_NOT_VIEWABLE;
layout = GTK_LAYOUT (item->canvas);
bin_window = gtk_layout_get_bin_window (layout);
retval = gdk_pointer_grab (bin_window,
FALSE,
event_mask,
NULL,
cursor,
etime);
if (retval != GDK_GRAB_SUCCESS)
return retval;
item->canvas->grabbed_item = item;
item->canvas->grabbed_event_mask = event_mask;
item->canvas->current_item = item; /* So that events go to the grabbed item */
return retval;
}
/**
* gnome_canvas_item_ungrab:
* @item: A canvas item that holds a grab.
* @etime: The timestamp for ungrabbing the mouse.
*
* Ungrabs the item, which must have been grabbed in the canvas, and ungrabs the
* mouse.
**/
void
gnome_canvas_item_ungrab (GnomeCanvasItem *item, guint32 etime)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
if (item->canvas->grabbed_item != item)
return;
item->canvas->grabbed_item = NULL;
gdk_pointer_ungrab (etime);
}
void
gnome_canvas_item_i2w_matrix (GnomeCanvasItem *item, cairo_matrix_t *matrix)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (matrix != NULL);
cairo_matrix_init_identity (matrix);
while (item) {
cairo_matrix_multiply (matrix, matrix, &item->matrix);
item = item->parent;
}
}
void
gnome_canvas_item_w2i_matrix (GnomeCanvasItem *item, cairo_matrix_t *matrix)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (matrix != NULL);
cairo_matrix_init_identity (matrix);
while (item) {
cairo_matrix_multiply (matrix, &item->matrix, matrix);
item = item->parent;
}
}
/**
* gnome_canvas_item_w2i:
* @item: A canvas item.
* @x: X coordinate to convert (input/output value).
* @y: Y coordinate to convert (input/output value).
*
* Converts a coordinate pair from world coordinates to item-relative
* coordinates.
**/
void
gnome_canvas_item_w2i (GnomeCanvasItem *item, gdouble *x, gdouble *y)
{
cairo_matrix_t matrix;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (x != NULL);
g_return_if_fail (y != NULL);
gnome_canvas_item_w2i_matrix (item, &matrix);
cairo_matrix_transform_point (&matrix, x, y);
}
/**
* gnome_canvas_item_i2w:
* @item: A canvas item.
* @x: X coordinate to convert (input/output value).
* @y: Y coordinate to convert (input/output value).
*
* Converts a coordinate pair from item-relative coordinates to world
* coordinates.
**/
void
gnome_canvas_item_i2w (GnomeCanvasItem *item, gdouble *x, gdouble *y)
{
cairo_matrix_t matrix;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (x != NULL);
g_return_if_fail (y != NULL);
gnome_canvas_item_i2w_matrix (item, &matrix);
cairo_matrix_transform_point (&matrix, x, y);
}
/**
* gnome_canvas_item_i2c_matrix:
* @item: A canvas item.
* @matrix: Matrix to take the resulting transformation matrix (return value).
*
* Gets the affine transform that converts from item-relative coordinates to
* canvas pixel coordinates.
**/
void
gnome_canvas_item_i2c_matrix (GnomeCanvasItem *item, cairo_matrix_t *matrix)
{
cairo_matrix_t i2w, w2c;
gnome_canvas_item_i2w_matrix (item, &i2w);
gnome_canvas_w2c_matrix (item->canvas, &w2c);
cairo_matrix_multiply (matrix, &i2w, &w2c);
}
/* Returns whether the item is an inferior of or is equal to the parent. */
static gint
is_descendant (GnomeCanvasItem *item, GnomeCanvasItem *parent)
{
for (; item; item = item->parent)
if (item == parent)
return TRUE;
return FALSE;
}
/**
* gnome_canvas_item_reparent:
* @item: A canvas item.
* @new_group: A canvas group.
*
* 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.
**/
void
gnome_canvas_item_reparent (GnomeCanvasItem *item, GnomeCanvasGroup *new_group)
{
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (GNOME_IS_CANVAS_GROUP (new_group));
/* Both items need to be in the same canvas */
g_return_if_fail (item->canvas == GNOME_CANVAS_ITEM (new_group)->canvas);
/* The group cannot be an inferior of the item or be the item itself --
* this also takes care of the case where the item is the root item of
* the canvas. */
g_return_if_fail (!is_descendant (GNOME_CANVAS_ITEM (new_group), item));
/* Everything is ok, now actually reparent the item */
g_object_ref (G_OBJECT (item)); /* protect it from the unref in group_remove */
redraw_if_visible (item);
group_remove (GNOME_CANVAS_GROUP (item->parent), item);
item->parent = GNOME_CANVAS_ITEM (new_group);
group_add (new_group, item);
/* Redraw and repick */
redraw_if_visible (item);
item->canvas->need_repick = TRUE;
g_object_unref (G_OBJECT (item));
}
/**
* gnome_canvas_item_grab_focus:
* @item: A canvas item.
*
* 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.
**/
void
gnome_canvas_item_grab_focus (GnomeCanvasItem *item)
{
GnomeCanvasItem *focused_item;
GdkEvent ev;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
g_return_if_fail (gtk_widget_get_can_focus (GTK_WIDGET (item->canvas)));
focused_item = item->canvas->focused_item;
if (focused_item) {
GtkLayout *layout;
GdkWindow *bin_window;
layout = GTK_LAYOUT (item->canvas);
bin_window = gtk_layout_get_bin_window (layout);
ev.focus_change.type = GDK_FOCUS_CHANGE;
ev.focus_change.window = bin_window;
ev.focus_change.send_event = FALSE;
ev.focus_change.in = FALSE;
emit_event (item->canvas, &ev);
}
item->canvas->focused_item = item;
gtk_widget_grab_focus (GTK_WIDGET (item->canvas));
if (focused_item) {
GtkLayout *layout;
GdkWindow *bin_window;
layout = GTK_LAYOUT (item->canvas);
bin_window = gtk_layout_get_bin_window (layout);
ev.focus_change.type = GDK_FOCUS_CHANGE;
ev.focus_change.window = bin_window;
ev.focus_change.send_event = FALSE;
ev.focus_change.in = TRUE;
emit_event (item->canvas, &ev);
}
}
/**
* gnome_canvas_item_get_bounds:
* @item: A canvas item.
* @x1: Leftmost edge of the bounding box (return value).
* @y1: Upper edge of the bounding box (return value).
* @x2: Rightmost edge of the bounding box (return value).
* @y2: Lower edge of the bounding box (return value).
*
* Queries the bounding box of a canvas item. The bounds are returned in the
* coordinate system of the item's parent.
**/
void
gnome_canvas_item_get_bounds (GnomeCanvasItem *item,
gdouble *x1,
gdouble *y1,
gdouble *x2,
gdouble *y2)
{
gdouble tx1, ty1, tx2, ty2;
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
tx1 = ty1 = tx2 = ty2 = 0.0;
/* Get the item's bounds in its coordinate system */
if (GNOME_CANVAS_ITEM_GET_CLASS (item)->bounds)
(* GNOME_CANVAS_ITEM_GET_CLASS (item)->bounds) (item, &tx1, &ty1, &tx2, &ty2);
/* Make the bounds relative to the item's parent coordinate system */
gnome_canvas_matrix_transform_rect (&item->matrix, &tx1, &ty1, &tx2, &ty2);
/* Return the values */
if (x1)
*x1 = tx1;
if (y1)
*y1 = ty1;
if (x2)
*x2 = tx2;
if (y2)
*y2 = ty2;
}
/**
* gnome_canvas_item_request_update
* @item: A canvas item.
*
* To be used only by item implementations. Requests that the canvas queue an
* update for the specified item.
**/
void
gnome_canvas_item_request_update (GnomeCanvasItem *item)
{
if (item->flags & GNOME_CANVAS_ITEM_NEED_UPDATE)
return;
item->flags |= GNOME_CANVAS_ITEM_NEED_UPDATE;
if (item->parent != NULL) {
/* Recurse up the tree */
gnome_canvas_item_request_update (item->parent);
} else {
/* Have reached the top of the tree, make sure the update call gets scheduled. */
gnome_canvas_request_update (item->canvas);
}
}
/*** GnomeCanvasGroup ***/
enum {
GROUP_PROP_0,
GROUP_PROP_X,
GROUP_PROP_Y
};
static void gnome_canvas_group_class_init (GnomeCanvasGroupClass *class);
static void gnome_canvas_group_init (GnomeCanvasGroup *group);
static void gnome_canvas_group_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec);
static void gnome_canvas_group_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec);
static void gnome_canvas_group_destroy (GnomeCanvasItem *object);
static void gnome_canvas_group_update (GnomeCanvasItem *item,
const cairo_matrix_t *matrix,
gint flags);
static void gnome_canvas_group_realize (GnomeCanvasItem *item);
static void gnome_canvas_group_unrealize (GnomeCanvasItem *item);
static void gnome_canvas_group_map (GnomeCanvasItem *item);
static void gnome_canvas_group_unmap (GnomeCanvasItem *item);
static void gnome_canvas_group_draw (GnomeCanvasItem *item,
GdkDrawable *drawable,
gint x, gint y,
gint width, gint height);
static GnomeCanvasItem *gnome_canvas_group_point (GnomeCanvasItem *item,
gdouble x, gdouble y,
gint cx, gint cy);
static void gnome_canvas_group_bounds (GnomeCanvasItem *item,
gdouble *x1, gdouble *y1,
gdouble *x2, gdouble *y2);
static GnomeCanvasItemClass *group_parent_class;
/**
* gnome_canvas_group_get_type:
*
* Registers the &GnomeCanvasGroup class if necessary, and returns the type ID
* associated to it.
*
* Return value: The type ID of the &GnomeCanvasGroup class.
**/
GType
gnome_canvas_group_get_type (void)
{
static GType canvas_group_type;
if (!canvas_group_type) {
const GTypeInfo object_info = {
sizeof (GnomeCanvasGroupClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) gnome_canvas_group_class_init,
(GClassFinalizeFunc) NULL,
NULL, /* class_data */
sizeof (GnomeCanvasGroup),
0, /* n_preallocs */
(GInstanceInitFunc) gnome_canvas_group_init,
NULL /* value_table */
};
canvas_group_type = g_type_register_static (
GNOME_TYPE_CANVAS_ITEM, "GnomeCanvasGroup",
&object_info, 0);
}
return canvas_group_type;
}
/* Class initialization function for GnomeCanvasGroupClass */
static void
gnome_canvas_group_class_init (GnomeCanvasGroupClass *class)
{
GObjectClass *object_class;
GnomeCanvasItemClass *item_class;
object_class = (GObjectClass *) class;
item_class = (GnomeCanvasItemClass *) class;
group_parent_class = g_type_class_peek_parent (class);
object_class->set_property = gnome_canvas_group_set_property;
object_class->get_property = gnome_canvas_group_get_property;
g_object_class_install_property
(object_class, GROUP_PROP_X,
g_param_spec_double ("x",
"X",
"X",
-G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(object_class, GROUP_PROP_Y,
g_param_spec_double ("y",
"Y",
"Y",
-G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
item_class->destroy = gnome_canvas_group_destroy;
item_class->update = gnome_canvas_group_update;
item_class->realize = gnome_canvas_group_realize;
item_class->unrealize = gnome_canvas_group_unrealize;
item_class->map = gnome_canvas_group_map;
item_class->unmap = gnome_canvas_group_unmap;
item_class->draw = gnome_canvas_group_draw;
item_class->point = gnome_canvas_group_point;
item_class->bounds = gnome_canvas_group_bounds;
}
/* Object initialization function for GnomeCanvasGroup */
static void
gnome_canvas_group_init (GnomeCanvasGroup *group)
{
}
/* Set_property handler for canvas groups */
static void
gnome_canvas_group_set_property (GObject *gobject, guint param_id,
const GValue *value, GParamSpec *pspec)
{
GnomeCanvasItem *item;
g_return_if_fail (GNOME_IS_CANVAS_GROUP (gobject));
item = GNOME_CANVAS_ITEM (gobject);
switch (param_id) {
case GROUP_PROP_X:
item->matrix.x0 = g_value_get_double (value);
break;
case GROUP_PROP_Y:
item->matrix.y0 = g_value_get_double (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, param_id, pspec);
break;
}
}
/* Get_property handler for canvas groups */
static void
gnome_canvas_group_get_property (GObject *gobject, guint param_id,
GValue *value, GParamSpec *pspec)
{
GnomeCanvasItem *item;
g_return_if_fail (GNOME_IS_CANVAS_GROUP (gobject));
item = GNOME_CANVAS_ITEM (gobject);
switch (param_id) {
case GROUP_PROP_X:
g_value_set_double (value, item->matrix.x0);
break;
case GROUP_PROP_Y:
g_value_set_double (value, item->matrix.y0);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, param_id, pspec);
break;
}
}
/* Destroy handler for canvas groups */
static void
gnome_canvas_group_destroy (GnomeCanvasItem *object)
{
GnomeCanvasGroup *group;
g_return_if_fail (GNOME_IS_CANVAS_GROUP (object));
group = GNOME_CANVAS_GROUP (object);
while (group->item_list) {
/* child is unref'ed by the child's group_remove (). */
g_object_run_dispose (G_OBJECT (group->item_list->data));
}
if (GNOME_CANVAS_ITEM_CLASS (group_parent_class)->destroy)
GNOME_CANVAS_ITEM_CLASS (group_parent_class)->destroy (object);
}
/* Update handler for canvas groups */
static void
gnome_canvas_group_update (GnomeCanvasItem *item,
const cairo_matrix_t *i2c,
gint flags)
{
GnomeCanvasGroup *group;
GList *list;
GnomeCanvasItem *i;
double x1, y1, x2, y2;
group = GNOME_CANVAS_GROUP (item);
(* group_parent_class->update) (item, i2c, flags);
x1 = G_MAXDOUBLE;
y1 = G_MAXDOUBLE;
x2 = -G_MAXDOUBLE;
y2 = -G_MAXDOUBLE;
for (list = group->item_list; list; list = list->next) {
i = list->data;
gnome_canvas_item_invoke_update (i, i2c, flags);
x1 = MIN (x1, i->x1);
x2 = MAX (x2, i->x2);
y1 = MIN (y1, i->y1);
y2 = MAX (y2, i->y2);
}
if (x1 >= x2 || y1 >= y2) {
item->x1 = item->x2 = item->y1 = item->y2 = 0;
} else {
item->x1 = x1;
item->y1 = y1;
item->x2 = x2;
item->y2 = y2;
}
}
/* Realize handler for canvas groups */
static void
gnome_canvas_group_realize (GnomeCanvasItem *item)
{
GnomeCanvasGroup *group;
GList *list;
GnomeCanvasItem *i;
group = GNOME_CANVAS_GROUP (item);
for (list = group->item_list; list; list = list->next) {
i = list->data;
if (!(i->flags & GNOME_CANVAS_ITEM_REALIZED))
(* GNOME_CANVAS_ITEM_GET_CLASS (i)->realize) (i);
}
(* group_parent_class->realize) (item);
}
/* Unrealize handler for canvas groups */
static void
gnome_canvas_group_unrealize (GnomeCanvasItem *item)
{
GnomeCanvasGroup *group;
GList *list;
GnomeCanvasItem *i;
group = GNOME_CANVAS_GROUP (item);
for (list = group->item_list; list; list = list->next) {
i = list->data;
if (i->flags & GNOME_CANVAS_ITEM_REALIZED)
(* GNOME_CANVAS_ITEM_GET_CLASS (i)->unrealize) (i);
}
(* group_parent_class->unrealize) (item);
}
/* Map handler for canvas groups */
static void
gnome_canvas_group_map (GnomeCanvasItem *item)
{
GnomeCanvasGroup *group;
GList *list;
GnomeCanvasItem *i;
group = GNOME_CANVAS_GROUP (item);
for (list = group->item_list; list; list = list->next) {
i = list->data;
if (!(i->flags & GNOME_CANVAS_ITEM_MAPPED))
(* GNOME_CANVAS_ITEM_GET_CLASS (i)->map) (i);
}
(* group_parent_class->map) (item);
}
/* Unmap handler for canvas groups */
static void
gnome_canvas_group_unmap (GnomeCanvasItem *item)
{
GnomeCanvasGroup *group;
GList *list;
GnomeCanvasItem *i;
group = GNOME_CANVAS_GROUP (item);
for (list = group->item_list; list; list = list->next) {
i = list->data;
if (i->flags & GNOME_CANVAS_ITEM_MAPPED)
(* GNOME_CANVAS_ITEM_GET_CLASS (i)->unmap) (i);
}
(* group_parent_class->unmap) (item);
}
/* Draw handler for canvas groups */
static void
gnome_canvas_group_draw (GnomeCanvasItem *item, GdkDrawable *drawable,
gint x, gint y, gint width, gint height)
{
GnomeCanvasGroup *group;
GList *list;
GnomeCanvasItem *child = NULL;
group = GNOME_CANVAS_GROUP (item);
for (list = group->item_list; list; list = list->next) {
child = list->data;
if (((child->flags & GNOME_CANVAS_ITEM_VISIBLE)
&& ((child->x1 < (x + width))
&& (child->y1 < (y + height))
&& (child->x2 > x)
&& (child->y2 > y)))
|| ((child->flags & GNOME_CANVAS_ITEM_ALWAYS_REDRAW)
&& (child->x1 < child->canvas->redraw_x2)
&& (child->y1 < child->canvas->redraw_y2)
&& (child->x2 > child->canvas->redraw_x1)
&& (child->y2 > child->canvas->redraw_y2)))
if (GNOME_CANVAS_ITEM_GET_CLASS (child)->draw)
(* GNOME_CANVAS_ITEM_GET_CLASS (child)->draw) (
child, drawable, x, y, width, height);
}
}
/* Point handler for canvas groups */
static GnomeCanvasItem *
gnome_canvas_group_point (GnomeCanvasItem *item,
gdouble x,
gdouble y,
gint cx,
gint cy)
{
GnomeCanvasGroup *group;
GList *list;
GnomeCanvasItem *child, *point_item;
group = GNOME_CANVAS_GROUP (item);
for (list = g_list_last (group->item_list); list; list = list->prev) {
child = list->data;
if ((child->x1 > cx) || (child->y1 > cy) || (child->x2 < cx) || (child->y2 < cy))
continue;
if (!(child->flags & GNOME_CANVAS_ITEM_VISIBLE))
continue;
point_item = gnome_canvas_item_invoke_point (child, x, y, cx, cy);
if (point_item)
return point_item;
}
return NULL;
}
/* Bounds handler for canvas groups */
static void
gnome_canvas_group_bounds (GnomeCanvasItem *item,
gdouble *x1,
gdouble *y1,
gdouble *x2,
gdouble *y2)
{
GnomeCanvasGroup *group;
GnomeCanvasItem *child;
GList *list;
gdouble tx1, ty1, tx2, ty2;
gdouble minx, miny, maxx, maxy;
gint set;
group = GNOME_CANVAS_GROUP (item);
/* Get the bounds of the first visible item */
child = NULL; /* Unnecessary but eliminates a warning. */
set = FALSE;
for (list = group->item_list; list; list = list->next) {
child = list->data;
if (child->flags & GNOME_CANVAS_ITEM_VISIBLE) {
set = TRUE;
gnome_canvas_item_get_bounds (child, &minx, &miny, &maxx, &maxy);
break;
}
}
/* If there were no visible items, return an empty bounding box */
if (!set) {
*x1 = *y1 = *x2 = *y2 = 0.0;
return;
}
/* Now we can grow the bounds using the rest of the items */
list = list->next;
for (; list; list = list->next) {
child = list->data;
if (!(child->flags & GNOME_CANVAS_ITEM_VISIBLE))
continue;
gnome_canvas_item_get_bounds (child, &tx1, &ty1, &tx2, &ty2);
if (tx1 < minx)
minx = tx1;
if (ty1 < miny)
miny = ty1;
if (tx2 > maxx)
maxx = tx2;
if (ty2 > maxy)
maxy = ty2;
}
*x1 = minx;
*y1 = miny;
*x2 = maxx;
*y2 = maxy;
}
/* Adds an item to a group */
static void
group_add (GnomeCanvasGroup *group, GnomeCanvasItem *item)
{
g_object_ref_sink (G_OBJECT (item));
if (!group->item_list) {
group->item_list = g_list_append (group->item_list, item);
group->item_list_end = group->item_list;
} else
group->item_list_end = g_list_append (group->item_list_end, item)->next;
if (group->item.flags & GNOME_CANVAS_ITEM_REALIZED)
(* GNOME_CANVAS_ITEM_GET_CLASS (item)->realize) (item);
if (group->item.flags & GNOME_CANVAS_ITEM_MAPPED)
(* GNOME_CANVAS_ITEM_GET_CLASS (item)->map) (item);
g_object_notify (G_OBJECT (item), "parent");
}
/* Removes an item from a group */
static void
group_remove (GnomeCanvasGroup *group, GnomeCanvasItem *item)
{
GList *children;
g_return_if_fail (GNOME_IS_CANVAS_GROUP (group));
g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
for (children = group->item_list; children; children = children->next)
if (children->data == item) {
if (item->flags & GNOME_CANVAS_ITEM_MAPPED)
(* GNOME_CANVAS_ITEM_GET_CLASS (item)->unmap) (item);
if (item->flags & GNOME_CANVAS_ITEM_REALIZED)
(* GNOME_CANVAS_ITEM_GET_CLASS (item)->unrealize) (item);
/* Unparent the child */
item->parent = NULL;
g_object_unref (G_OBJECT (item));
/* Remove it from the list */
if (children == group->item_list_end)
group->item_list_end = children->prev;
group->item_list = g_list_remove_link (group->item_list, children);
g_list_free (children);
break;
}
}
/*** GnomeCanvas ***/
enum {
DRAW_BACKGROUND,
LAST_SIGNAL
};
static void gnome_canvas_class_init (GnomeCanvasClass *class);
static void gnome_canvas_init (GnomeCanvas *canvas);
static void gnome_canvas_dispose (GObject *object);
static void gnome_canvas_map (GtkWidget *widget);
static void gnome_canvas_unmap (GtkWidget *widget);
static void gnome_canvas_realize (GtkWidget *widget);
static void gnome_canvas_unrealize (GtkWidget *widget);
static void gnome_canvas_size_allocate (GtkWidget *widget,
GtkAllocation *allocation);
static gint gnome_canvas_button (GtkWidget *widget,
GdkEventButton *event);
static gint gnome_canvas_motion (GtkWidget *widget,
GdkEventMotion *event);
static gint gnome_canvas_expose (GtkWidget *widget,
GdkEventExpose *event);
static gboolean gnome_canvas_key (GtkWidget *widget,
GdkEventKey *event);
static gint gnome_canvas_crossing (GtkWidget *widget,
GdkEventCrossing *event);
static gint gnome_canvas_focus_in (GtkWidget *widget,
GdkEventFocus *event);
static gint gnome_canvas_focus_out (GtkWidget *widget,
GdkEventFocus *event);
static void gnome_canvas_request_update_real (GnomeCanvas *canvas);
static void gnome_canvas_draw_background (GnomeCanvas *canvas,
GdkDrawable *drawable,
gint x,
gint y,
gint width,
gint height);
static GtkLayoutClass *canvas_parent_class;
static guint canvas_signals[LAST_SIGNAL];
enum {
PROP_0,
PROP_FOCUSED_ITEM,
};
/**
* gnome_canvas_get_type:
*
* Registers the &GnomeCanvas class if necessary, and returns the type ID
* associated to it.
*
* Return value: The type ID of the &GnomeCanvas class.
**/
GType
gnome_canvas_get_type (void)
{
static GType canvas_type;
if (!canvas_type) {
const GTypeInfo object_info = {
sizeof (GnomeCanvasClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) gnome_canvas_class_init,
(GClassFinalizeFunc) NULL,
NULL, /* class_data */
sizeof (GnomeCanvas),
0, /* n_preallocs */
(GInstanceInitFunc) gnome_canvas_init,
NULL /* value_table */
};
canvas_type = g_type_register_static (GTK_TYPE_LAYOUT, "GnomeCanvas",
&object_info, 0);
}
return canvas_type;
}
static void
gnome_canvas_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
switch (prop_id) {
case PROP_FOCUSED_ITEM:
g_value_set_object (value, GNOME_CANVAS (object)->focused_item);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gnome_canvas_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
switch (prop_id) {
case PROP_FOCUSED_ITEM:
GNOME_CANVAS (object)->focused_item = g_value_get_object (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* Class initialization function for GnomeCanvasClass */
static void
gnome_canvas_class_init (GnomeCanvasClass *klass)
{
GObjectClass *object_class;
GtkWidgetClass *widget_class;
object_class = (GObjectClass *)klass;
widget_class = (GtkWidgetClass *) klass;
canvas_parent_class = g_type_class_peek_parent (klass);
object_class->set_property = gnome_canvas_set_property;
object_class->get_property = gnome_canvas_get_property;
object_class->dispose = gnome_canvas_dispose;
widget_class->map = gnome_canvas_map;
widget_class->unmap = gnome_canvas_unmap;
widget_class->realize = gnome_canvas_realize;
widget_class->unrealize = gnome_canvas_unrealize;
widget_class->size_allocate = gnome_canvas_size_allocate;
widget_class->button_press_event = gnome_canvas_button;
widget_class->button_release_event = gnome_canvas_button;
widget_class->motion_notify_event = gnome_canvas_motion;
widget_class->expose_event = gnome_canvas_expose;
widget_class->key_press_event = gnome_canvas_key;
widget_class->key_release_event = gnome_canvas_key;
widget_class->enter_notify_event = gnome_canvas_crossing;
widget_class->leave_notify_event = gnome_canvas_crossing;
widget_class->focus_in_event = gnome_canvas_focus_in;
widget_class->focus_out_event = gnome_canvas_focus_out;
klass->draw_background = gnome_canvas_draw_background;
klass->request_update = gnome_canvas_request_update_real;
g_object_class_install_property (object_class, PROP_FOCUSED_ITEM,
g_param_spec_object ("focused_item", NULL, NULL,
GNOME_TYPE_CANVAS_ITEM,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
canvas_signals[DRAW_BACKGROUND] =
g_signal_new ("draw_background",
G_TYPE_FROM_CLASS (object_class),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GnomeCanvasClass, draw_background),
NULL, NULL,
gnome_canvas_marshal_VOID__OBJECT_INT_INT_INT_INT,
G_TYPE_NONE, 5, GDK_TYPE_DRAWABLE,
G_TYPE_INT, G_TYPE_INT, G_TYPE_INT, G_TYPE_INT);
gail_canvas_init ();
}
/* Callback used when the root item of a canvas is destroyed. The user should
* never ever do this, so we panic if this happens.
*/
G_GNUC_NORETURN static void
panic_root_finalized (gpointer data, GObject *gone_object)
{
g_error ("Eeeek, root item %p of canvas %p was destroyed!", gone_object, data);
}
/* Object initialization function for GnomeCanvas */
static void
gnome_canvas_init (GnomeCanvas *canvas)
{
GtkLayout *layout;
guint layout_width, layout_height;
layout = GTK_LAYOUT (canvas);
gtk_layout_get_size (layout, &layout_width, &layout_height);
gtk_widget_set_can_focus (GTK_WIDGET (canvas), TRUE);
canvas->need_update = FALSE;
canvas->idle_id = 0;
canvas->scroll_x1 = 0.0;
canvas->scroll_y1 = 0.0;
canvas->scroll_x2 = layout_width;
canvas->scroll_y2 = layout_height;
canvas->pixels_per_unit = 1.0;
canvas->pick_event.type = GDK_LEAVE_NOTIFY;
canvas->pick_event.crossing.x = 0;
canvas->pick_event.crossing.y = 0;
/* This may not be what people want, but it is set to be turned on by
* default to have the same initial behavior as the canvas in GNOME 1.4.
*/
canvas->center_scroll_region = TRUE;
gtk_layout_set_hadjustment (GTK_LAYOUT (canvas), NULL);
gtk_layout_set_vadjustment (GTK_LAYOUT (canvas), NULL);
/* Disable the gtk+ gdouble buffering since the canvas uses it's own. */
gtk_widget_set_double_buffered (GTK_WIDGET (canvas), FALSE);
/* Create the root item as a special case */
canvas->root = GNOME_CANVAS_ITEM (
g_object_new (gnome_canvas_group_get_type (), NULL));
canvas->root->canvas = canvas;
g_object_ref_sink (canvas->root);
g_object_weak_ref (G_OBJECT (canvas->root), panic_root_finalized, canvas);
canvas->need_repick = TRUE;
}
/* Convenience function to remove the idle handler of a canvas */
static void
remove_idle (GnomeCanvas *canvas)
{
if (canvas->idle_id == 0)
return;
g_source_remove (canvas->idle_id);
canvas->idle_id = 0;
}
/* Removes the transient state of the canvas (idle handler, grabs). */
static void
shutdown_transients (GnomeCanvas *canvas)
{
if (canvas->grabbed_item) {
canvas->grabbed_item = NULL;
gdk_pointer_ungrab (GDK_CURRENT_TIME);
}
remove_idle (canvas);
}
/* Dispose handler for GnomeCanvas */
static void
gnome_canvas_dispose (GObject *object)
{
GnomeCanvas *canvas;
g_return_if_fail (GNOME_IS_CANVAS (object));
/* remember, dispose can be run multiple times! */
canvas = GNOME_CANVAS (object);
if (canvas->root) {
g_object_weak_unref (G_OBJECT (canvas->root), panic_root_finalized, canvas);
g_object_unref (G_OBJECT (canvas->root));
canvas->root = NULL;
}
shutdown_transients (canvas);
if (G_OBJECT_CLASS (canvas_parent_class)->dispose)
G_OBJECT_CLASS (canvas_parent_class)->dispose (object);
}
/**
* gnome_canvas_new:
*
* Creates a new empty canvas in non-antialiased mode.
*
* Return value: A newly-created canvas.
**/
GtkWidget *
gnome_canvas_new (void)
{
return GTK_WIDGET (g_object_new (gnome_canvas_get_type (), NULL));
}
/* Map handler for the canvas */
static void
gnome_canvas_map (GtkWidget *widget)
{
GnomeCanvas *canvas;
g_return_if_fail (GNOME_IS_CANVAS (widget));
/* Normal widget mapping stuff */
if (GTK_WIDGET_CLASS (canvas_parent_class)->map)
(* GTK_WIDGET_CLASS (canvas_parent_class)->map) (widget);
canvas = GNOME_CANVAS (widget);
if (canvas->need_update)
add_idle (canvas);
/* Map items */
if (GNOME_CANVAS_ITEM_GET_CLASS (canvas->root)->map)
(* GNOME_CANVAS_ITEM_GET_CLASS (canvas->root)->map) (canvas->root);
}
/* Unmap handler for the canvas */
static void
gnome_canvas_unmap (GtkWidget *widget)
{
GnomeCanvas *canvas;
g_return_if_fail (GNOME_IS_CANVAS (widget));
canvas = GNOME_CANVAS (widget);
shutdown_transients (canvas);
/* Unmap items */
if (GNOME_CANVAS_ITEM_GET_CLASS (canvas->root)->unmap)
(* GNOME_CANVAS_ITEM_GET_CLASS (canvas->root)->unmap) (canvas->root);
/* Normal widget unmapping stuff */
if (GTK_WIDGET_CLASS (canvas_parent_class)->unmap)
(* GTK_WIDGET_CLASS (canvas_parent_class)->unmap) (widget);
}
/* Realize handler for the canvas */
static void
gnome_canvas_realize (GtkWidget *widget)
{
GnomeCanvas *canvas;
GtkLayout *layout;
GdkWindow *bin_window;
g_return_if_fail (GNOME_IS_CANVAS (widget));
/* Normal widget realization stuff */
if (GTK_WIDGET_CLASS (canvas_parent_class)->realize)
(* GTK_WIDGET_CLASS (canvas_parent_class)->realize) (widget);
canvas = GNOME_CANVAS (widget);
layout = GTK_LAYOUT (canvas);
bin_window = gtk_layout_get_bin_window (layout);
gdk_window_set_events (bin_window,
(gdk_window_get_events (bin_window)
| GDK_EXPOSURE_MASK
| GDK_BUTTON_PRESS_MASK
| GDK_BUTTON_RELEASE_MASK
| GDK_POINTER_MOTION_MASK
| GDK_KEY_PRESS_MASK
| GDK_KEY_RELEASE_MASK
| GDK_ENTER_NOTIFY_MASK
| GDK_LEAVE_NOTIFY_MASK
| GDK_FOCUS_CHANGE_MASK));
/* Create our own temporary pixmap gc and realize all the items */
canvas->pixmap_gc = gdk_gc_new (bin_window);
(* GNOME_CANVAS_ITEM_GET_CLASS (canvas->root)->realize) (canvas->root);
}
/* Unrealize handler for the canvas */
static void
gnome_canvas_unrealize (GtkWidget *widget)
{
GnomeCanvas *canvas;
g_return_if_fail (GNOME_IS_CANVAS (widget));
canvas = GNOME_CANVAS (widget);
shutdown_transients (canvas);
/* Unrealize items and parent widget */
(* GNOME_CANVAS_ITEM_GET_CLASS (canvas->root)->unrealize) (canvas->root);
g_object_unref (canvas->pixmap_gc);
canvas->pixmap_gc = NULL;
if (GTK_WIDGET_CLASS (canvas_parent_class)->unrealize)
(* GTK_WIDGET_CLASS (canvas_parent_class)->unrealize) (widget);
}
/* Handles scrolling of the canvas. Adjusts the scrolling and zooming offset to
* keep as much as possible of the canvas scrolling region in view.
*/
static void
scroll_to (GnomeCanvas *canvas, gint cx, gint cy)
{
GtkWidget *widget;
GtkLayout *layout;
GtkAllocation allocation;
GtkAdjustment *hadjustment;
GtkAdjustment *vadjustment;
guint layout_width, layout_height;
gint scroll_width, scroll_height;
gint right_limit, bottom_limit;
gint old_zoom_xofs, old_zoom_yofs;
gint canvas_width, canvas_height;
widget = GTK_WIDGET (canvas);
gtk_widget_get_allocation (widget, &allocation);
layout = GTK_LAYOUT (canvas);
hadjustment = gtk_layout_get_hadjustment (layout);
vadjustment = gtk_layout_get_vadjustment (layout);
gtk_layout_get_size (layout, &layout_width, &layout_height);
canvas_width = allocation.width;
canvas_height = allocation.height;
scroll_width =
floor ((canvas->scroll_x2 - canvas->scroll_x1) *
canvas->pixels_per_unit + 0.5);
scroll_height =
floor ((canvas->scroll_y2 - canvas->scroll_y1) *
canvas->pixels_per_unit + 0.5);
right_limit = scroll_width - canvas_width;
bottom_limit = scroll_height - canvas_height;
old_zoom_xofs = canvas->zoom_xofs;
old_zoom_yofs = canvas->zoom_yofs;
if (right_limit < 0) {
cx = 0;
if (canvas->center_scroll_region) {
canvas->zoom_xofs = (canvas_width - scroll_width) / 2;
scroll_width = canvas_width;
} else
canvas->zoom_xofs = 0;
} else if (cx < 0) {
cx = 0;
canvas->zoom_xofs = 0;
} else if (cx > right_limit) {
cx = right_limit;
canvas->zoom_xofs = 0;
} else
canvas->zoom_xofs = 0;
if (bottom_limit < 0) {
cy = 0;
if (canvas->center_scroll_region) {
canvas->zoom_yofs = (canvas_height - scroll_height) / 2;
scroll_height = canvas_height;
} else
canvas->zoom_yofs = 0;
} else if (cy < 0) {
cy = 0;
canvas->zoom_yofs = 0;
} else if (cy > bottom_limit) {
cy = bottom_limit;
canvas->zoom_yofs = 0;
} else
canvas->zoom_yofs = 0;
if ((canvas->zoom_xofs != old_zoom_xofs) || (canvas->zoom_yofs != old_zoom_yofs)) {
/* This can only occur, if either canvas size or widget size changes */
/* So I think we can request full redraw here */
/* The reason is, that coverage UTA will be invalidated by offset change */
/* fixme: Strictly this is not correct - we have to remove our own idle (Lauris) */
/* More stuff - we have to mark root as needing fresh affine (Lauris) */
if (!(canvas->root->flags & GNOME_CANVAS_ITEM_NEED_AFFINE)) {
canvas->root->flags |= GNOME_CANVAS_ITEM_NEED_AFFINE;
gnome_canvas_request_update (canvas);
}
gtk_widget_queue_draw (GTK_WIDGET (canvas));
}
if (hadjustment)
gtk_adjustment_set_value (hadjustment, cx);
if (vadjustment)
gtk_adjustment_set_value (vadjustment, cy);
if ((scroll_width != (gint) layout_width)
|| (scroll_height != (gint) layout_height))
gtk_layout_set_size (GTK_LAYOUT (canvas), scroll_width, scroll_height);
}
/* Size allocation handler for the canvas */
static void
gnome_canvas_size_allocate (GtkWidget *widget, GtkAllocation *allocation)
{
GtkLayout *layout;
GtkAdjustment *hadjustment;
GtkAdjustment *vadjustment;
g_return_if_fail (GNOME_IS_CANVAS (widget));
g_return_if_fail (allocation != NULL);
if (GTK_WIDGET_CLASS (canvas_parent_class)->size_allocate)
(* GTK_WIDGET_CLASS (canvas_parent_class)->size_allocate) (widget, allocation);
layout = GTK_LAYOUT (widget);
hadjustment = gtk_layout_get_hadjustment (layout);
vadjustment = gtk_layout_get_vadjustment (layout);
/* Recenter the view, if appropriate */
g_object_freeze_notify (G_OBJECT (hadjustment));
g_object_freeze_notify (G_OBJECT (vadjustment));
gtk_adjustment_set_page_size (hadjustment, allocation->width);
gtk_adjustment_set_page_increment (hadjustment, allocation->width / 2);
gtk_adjustment_set_page_size (vadjustment, allocation->height);
gtk_adjustment_set_page_increment (vadjustment, allocation->height / 2);
scroll_to (GNOME_CANVAS (widget),
gtk_adjustment_get_value (hadjustment),
gtk_adjustment_get_value (vadjustment));
g_object_thaw_notify (G_OBJECT (hadjustment));
g_object_thaw_notify (G_OBJECT (vadjustment));
}
/* Emits an event for an item in the canvas, be it the current item, grabbed
* item, or focused item, as appropriate.
*/
static gint
emit_event (GnomeCanvas *canvas, GdkEvent *event)
{
GdkEvent *ev;
gint finished;
GnomeCanvasItem *item;
GnomeCanvasItem *parent;
guint mask;
/* Perform checks for grabbed items */
if (canvas->grabbed_item &&
!is_descendant (canvas->current_item, canvas->grabbed_item)) {
/* I think this warning is annoying and I don't know what it's for
* so I'll disable it for now.
*/
/* g_warning ("emit_event() returning FALSE!\n");*/
return FALSE;
}
if (canvas->grabbed_item) {
switch (event->type) {
case GDK_ENTER_NOTIFY:
mask = GDK_ENTER_NOTIFY_MASK;
break;
case GDK_LEAVE_NOTIFY:
mask = GDK_LEAVE_NOTIFY_MASK;
break;
case GDK_MOTION_NOTIFY:
mask = GDK_POINTER_MOTION_MASK;
break;
case GDK_BUTTON_PRESS:
case GDK_2BUTTON_PRESS:
case GDK_3BUTTON_PRESS:
mask = GDK_BUTTON_PRESS_MASK;
break;
case GDK_BUTTON_RELEASE:
mask = GDK_BUTTON_RELEASE_MASK;
break;
case GDK_KEY_PRESS:
mask = GDK_KEY_PRESS_MASK;
break;
case GDK_KEY_RELEASE:
mask = GDK_KEY_RELEASE_MASK;
break;
case GDK_SCROLL:
mask = GDK_SCROLL_MASK;
break;
default:
mask = 0;
break;
}
if (!(mask & canvas->grabbed_event_mask))
return FALSE;
}
/* Convert to world coordinates -- we have two cases because of diferent
* offsets of the fields in the event structures.
*/
ev = gdk_event_copy (event);
switch (ev->type)
{
case GDK_ENTER_NOTIFY:
case GDK_LEAVE_NOTIFY:
gnome_canvas_window_to_world (canvas,
ev->crossing.x, ev->crossing.y,
&ev->crossing.x, &ev->crossing.y);
break;
case GDK_MOTION_NOTIFY:
case GDK_BUTTON_PRESS:
case GDK_2BUTTON_PRESS:
case GDK_3BUTTON_PRESS:
case GDK_BUTTON_RELEASE:
gnome_canvas_window_to_world (canvas,
ev->motion.x, ev->motion.y,
&ev->motion.x, &ev->motion.y);
break;
default:
break;
}
/* Choose where we send the event */
item = canvas->current_item;
if (canvas->focused_item
&& ((event->type == GDK_KEY_PRESS) ||
(event->type == GDK_KEY_RELEASE) ||
(event->type == GDK_FOCUS_CHANGE)))
item = canvas->focused_item;
/* The event is propagated up the hierarchy (for if someone connected to
* a group instead of a leaf event), and emission is stopped if a
* handler returns TRUE, just like for GtkWidget events.
*/
finished = FALSE;
while (item && !finished) {
g_object_ref (G_OBJECT (item));
g_signal_emit (item, item_signals[ITEM_EVENT], 0,
ev, &finished);
parent = item->parent;
g_object_unref (G_OBJECT (item));
item = parent;
}
gdk_event_free (ev);
return finished;
}
/* Re-picks the current item in the canvas, based on the event's coordinates.
* Also emits enter/leave events for items as appropriate.
*/
static gint
pick_current_item (GnomeCanvas *canvas, GdkEvent *event)
{
gint button_down;
gdouble x, y;
gint cx, cy;
gint retval;
retval = FALSE;
/* If a button is down, we'll perform enter and leave events on the
* current item, but not enter on any other item. This is more or less
* like X pointer grabbing for canvas items.
*/
button_down = canvas->state & (GDK_BUTTON1_MASK
| GDK_BUTTON2_MASK
| GDK_BUTTON3_MASK
| GDK_BUTTON4_MASK
| GDK_BUTTON5_MASK);
if (!button_down)
canvas->left_grabbed_item = FALSE;
/* Save the event in the canvas. This is used to synthesize enter and
* leave events in case the current item changes. It is also used to
* re-pick the current item if the current one gets deleted. Also,
* synthesize an enter event.
*/
if (event != &canvas->pick_event) {
if ((event->type == GDK_MOTION_NOTIFY) || (event->type == GDK_BUTTON_RELEASE)) {
/* these fields have the same offsets in both types of events */
canvas->pick_event.crossing.type = GDK_ENTER_NOTIFY;
canvas->pick_event.crossing.window = event->motion.window;
canvas->pick_event.crossing.send_event = event->motion.send_event;
canvas->pick_event.crossing.subwindow = NULL;
canvas->pick_event.crossing.x = event->motion.x;
canvas->pick_event.crossing.y = event->motion.y;
canvas->pick_event.crossing.mode = GDK_CROSSING_NORMAL;
canvas->pick_event.crossing.detail = GDK_NOTIFY_NONLINEAR;
canvas->pick_event.crossing.focus = FALSE;
canvas->pick_event.crossing.state = event->motion.state;
/* these fields don't have the same offsets in both types of events */
if (event->type == GDK_MOTION_NOTIFY) {
canvas->pick_event.crossing.x_root = event->motion.x_root;
canvas->pick_event.crossing.y_root = event->motion.y_root;
} else {
canvas->pick_event.crossing.x_root = event->button.x_root;
canvas->pick_event.crossing.y_root = event->button.y_root;
}
} else
canvas->pick_event = *event;
}
/* Don't do anything else if this is a recursive call */
if (canvas->in_repick)
return retval;
/* LeaveNotify means that there is no current item, so we don't look for one */
if (canvas->pick_event.type != GDK_LEAVE_NOTIFY) {
/* these fields don't have the same offsets in both types of events */
if (canvas->pick_event.type == GDK_ENTER_NOTIFY) {
x = canvas->pick_event.crossing.x - canvas->zoom_xofs;
y = canvas->pick_event.crossing.y - canvas->zoom_yofs;
} else {
x = canvas->pick_event.motion.x - canvas->zoom_xofs;
y = canvas->pick_event.motion.y - canvas->zoom_yofs;
}
/* canvas pixel coords */
cx = (gint) (x + 0.5);
cy = (gint) (y + 0.5);
/* world coords */
x = canvas->scroll_x1 + x / canvas->pixels_per_unit;
y = canvas->scroll_y1 + y / canvas->pixels_per_unit;
/* find the closest item */
if (canvas->root->flags & GNOME_CANVAS_ITEM_VISIBLE)
canvas->new_current_item = gnome_canvas_item_invoke_point (canvas->root, x, y, cx, cy);
else
canvas->new_current_item = NULL;
} else
canvas->new_current_item = NULL;
if ((canvas->new_current_item == canvas->current_item) && !canvas->left_grabbed_item)
return retval; /* current item did not change */
/* Synthesize events for old and new current items */
if ((canvas->new_current_item != canvas->current_item)
&& (canvas->current_item != NULL)
&& !canvas->left_grabbed_item) {
GdkEvent new_event;
new_event = canvas->pick_event;
new_event.type = GDK_LEAVE_NOTIFY;
new_event.crossing.detail = GDK_NOTIFY_ANCESTOR;
new_event.crossing.subwindow = NULL;
canvas->in_repick = TRUE;
retval = emit_event (canvas, &new_event);
canvas->in_repick = FALSE;
}
/* new_current_item may have been set to NULL during the call to emit_event() above */
if ((canvas->new_current_item != canvas->current_item) && button_down) {
canvas->left_grabbed_item = TRUE;
return retval;
}
/* Handle the rest of cases */
canvas->left_grabbed_item = FALSE;
canvas->current_item = canvas->new_current_item;
if (canvas->current_item != NULL) {
GdkEvent new_event;
new_event = canvas->pick_event;
new_event.type = GDK_ENTER_NOTIFY;
new_event.crossing.detail = GDK_NOTIFY_ANCESTOR;
new_event.crossing.subwindow = NULL;
retval = emit_event (canvas, &new_event);
}
return retval;
}
/* Button event handler for the canvas */
static gint
gnome_canvas_button (GtkWidget *widget, GdkEventButton *event)
{
GnomeCanvas *canvas;
GtkLayout *layout;
GdkWindow *bin_window;
gint mask;
gint retval;
g_return_val_if_fail (GNOME_IS_CANVAS (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
retval = FALSE;
canvas = GNOME_CANVAS (widget);
layout = GTK_LAYOUT (canvas);
bin_window = gtk_layout_get_bin_window (layout);
/*
* dispatch normally regardless of the event's window if an item has
* has a pointer grab in effect
*/
if (!canvas->grabbed_item && event->window != bin_window)
return retval;
switch (event->button) {
case 1:
mask = GDK_BUTTON1_MASK;
break;
case 2:
mask = GDK_BUTTON2_MASK;
break;
case 3:
mask = GDK_BUTTON3_MASK;
break;
case 4:
mask = GDK_BUTTON4_MASK;
break;
case 5:
mask = GDK_BUTTON5_MASK;
break;
default:
mask = 0;
}
switch (event->type) {
case GDK_BUTTON_PRESS:
case GDK_2BUTTON_PRESS:
case GDK_3BUTTON_PRESS:
/* Pick the current item as if the button were not pressed, and
* then process the event.
*/
canvas->state = event->state;
pick_current_item (canvas, (GdkEvent *) event);
canvas->state ^= mask;
retval = emit_event (canvas, (GdkEvent *) event);
break;
case GDK_BUTTON_RELEASE:
/* Process the event as if the button were pressed, then repick
* after the button has been released
*/
canvas->state = event->state;
retval = emit_event (canvas, (GdkEvent *) event);
event->state ^= mask;
canvas->state = event->state;
pick_current_item (canvas, (GdkEvent *) event);
event->state ^= mask;
break;
default:
g_assert_not_reached ();
}
return retval;
}
/* Motion event handler for the canvas */
static gint
gnome_canvas_motion (GtkWidget *widget, GdkEventMotion *event)
{
GnomeCanvas *canvas;
GtkLayout *layout;
GdkWindow *bin_window;
g_return_val_if_fail (GNOME_IS_CANVAS (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
canvas = GNOME_CANVAS (widget);
layout = GTK_LAYOUT (widget);
bin_window = gtk_layout_get_bin_window (layout);
if (event->window != bin_window)
return FALSE;
canvas->state = event->state;
pick_current_item (canvas, (GdkEvent *) event);
return emit_event (canvas, (GdkEvent *) event);
}
/* Key event handler for the canvas */
static gboolean
gnome_canvas_key (GtkWidget *widget, GdkEventKey *event)
{
GnomeCanvas *canvas;
g_return_val_if_fail (GNOME_IS_CANVAS (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
canvas = GNOME_CANVAS (widget);
if (!emit_event (canvas, (GdkEvent *) event)) {
GtkWidgetClass *widget_class;
widget_class = GTK_WIDGET_CLASS (canvas_parent_class);
if (event->type == GDK_KEY_PRESS) {
if (widget_class->key_press_event)
return (* widget_class->key_press_event) (widget, event);
} else if (event->type == GDK_KEY_RELEASE) {
if (widget_class->key_release_event)
return (* widget_class->key_release_event) (widget, event);
} else
g_assert_not_reached ();
return FALSE;
} else
return TRUE;
}
/* Crossing event handler for the canvas */
static gint
gnome_canvas_crossing (GtkWidget *widget, GdkEventCrossing *event)
{
GnomeCanvas *canvas;
GtkLayout *layout;
GdkWindow *bin_window;
g_return_val_if_fail (GNOME_IS_CANVAS (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
canvas = GNOME_CANVAS (widget);
layout = GTK_LAYOUT (canvas);
bin_window = gtk_layout_get_bin_window (layout);
if (event->window != bin_window)
return FALSE;
canvas->state = event->state;
return pick_current_item (canvas, (GdkEvent *) event);
}
/* Focus in handler for the canvas */
static gint
gnome_canvas_focus_in (GtkWidget *widget, GdkEventFocus *event)
{
GnomeCanvas *canvas;
/* XXX Can't access flags directly anymore, but is it really needed?
* If so, could we call gtk_widget_send_focus_change() instead? */
#if 0
GTK_WIDGET_SET_FLAGS (widget, GTK_HAS_FOCUS);
#endif
canvas = GNOME_CANVAS (widget);
if (canvas->focused_item)
return emit_event (canvas, (GdkEvent *) event);
else
return FALSE;
}
/* Focus out handler for the canvas */
static gint
gnome_canvas_focus_out (GtkWidget *widget, GdkEventFocus *event)
{
GnomeCanvas *canvas;
/* XXX Can't access flags directly anymore, but is it really needed?
* If so, could we call gtk_widget_send_focus_change() instead? */
#if 0
GTK_WIDGET_UNSET_FLAGS (widget, GTK_HAS_FOCUS);
#endif
canvas = GNOME_CANVAS (widget);
if (canvas->focused_item)
return emit_event (canvas, (GdkEvent *) event);
else
return FALSE;
}
#define REDRAW_QUANTUM_SIZE 512
static void
gnome_canvas_paint_rect (GnomeCanvas *canvas, gint x0, gint y0, gint x1, gint y1)
{
GtkWidget *widget;
GtkLayout *layout;
GdkWindow *bin_window;
GtkAllocation allocation;
GtkAdjustment *hadjustment;
GtkAdjustment *vadjustment;
gint draw_x1, draw_y1;
gint draw_x2, draw_y2;
gint draw_width, draw_height;
gdouble hadjustment_value;
gdouble vadjustment_value;
GdkPixmap *pixmap;
GdkVisual *visual;
gint depth;
g_return_if_fail (!canvas->need_update);
widget = GTK_WIDGET (canvas);
gtk_widget_get_allocation (widget, &allocation);
layout = GTK_LAYOUT (canvas);
bin_window = gtk_layout_get_bin_window (layout);
hadjustment = gtk_layout_get_hadjustment (layout);
vadjustment = gtk_layout_get_vadjustment (layout);
hadjustment_value = gtk_adjustment_get_value (hadjustment);
vadjustment_value = gtk_adjustment_get_value (vadjustment);
draw_x1 = MAX (x0, hadjustment_value - canvas->zoom_xofs);
draw_y1 = MAX (y0, vadjustment_value - canvas->zoom_yofs);
draw_x2 = MIN (draw_x1 + allocation.width, x1);
draw_y2 = MIN (draw_y1 + allocation.height, y1);
draw_width = draw_x2 - draw_x1;
draw_height = draw_y2 - draw_y1;
if (draw_width < 1 || draw_height < 1)
return;
canvas->redraw_x1 = draw_x1;
canvas->redraw_y1 = draw_y1;
canvas->redraw_x2 = draw_x2;
canvas->redraw_y2 = draw_y2;
canvas->draw_xofs = draw_x1;
canvas->draw_yofs = draw_y1;
visual = gtk_widget_get_visual (widget);
depth = gdk_visual_get_depth (visual);
pixmap = gdk_pixmap_new (bin_window,
draw_width, draw_height, depth);
g_signal_emit (G_OBJECT (canvas), canvas_signals[DRAW_BACKGROUND], 0, pixmap,
draw_x1, draw_y1, draw_width, draw_height);
if (canvas->root->flags & GNOME_CANVAS_ITEM_VISIBLE)
(* GNOME_CANVAS_ITEM_GET_CLASS (canvas->root)->draw) (
canvas->root, pixmap,
draw_x1, draw_y1,
draw_width, draw_height);
/* Copy the pixmap to the window and clean up */
gdk_draw_drawable (bin_window,
canvas->pixmap_gc,
pixmap,
0, 0,
draw_x1 + canvas->zoom_xofs,
draw_y1 + canvas->zoom_yofs,
draw_width, draw_height);
g_object_unref (pixmap);
}
/* Expose handler for the canvas */
static gint
gnome_canvas_expose (GtkWidget *widget, GdkEventExpose *event)
{
GnomeCanvas *canvas;
GtkLayout *layout;
GdkWindow *bin_window;
GdkRectangle *rects;
gint n_rects;
gint i;
canvas = GNOME_CANVAS (widget);
layout = GTK_LAYOUT (canvas);
bin_window = gtk_layout_get_bin_window (layout);
if (!gtk_widget_is_drawable (widget) || (event->window != bin_window))
return FALSE;
#ifdef VERBOSE
g_print ("Expose\n");
#endif
gdk_region_get_rectangles (event->region, &rects, &n_rects);
for (i = 0; i < n_rects; i++) {
GdkRectangle rect;
rect.x = rects[i].x - canvas->zoom_xofs;
rect.y = rects[i].y - canvas->zoom_yofs;
rect.width = rects[i].width;
rect.height = rects[i].height;
if (canvas->need_update) {
gnome_canvas_request_redraw (canvas,
rect.x, rect.y,
rect.x + rect.width,
rect.y + rect.height);
} else {
/* No pending updates, draw exposed area immediately */
gnome_canvas_paint_rect (canvas,
rect.x, rect.y,
rect.x + rect.width,
rect.y + rect.height);
/* And call expose on parent container class */
if (GTK_WIDGET_CLASS (canvas_parent_class)->expose_event)
(* GTK_WIDGET_CLASS (canvas_parent_class)->expose_event) (
widget, event);
}
}
g_free (rects);
return FALSE;
}
static void
gnome_canvas_draw_background (GnomeCanvas *canvas, GdkDrawable *drawable,
gint x, gint y, gint width, gint height)
{
GtkStyle *style;
style = gtk_widget_get_style (GTK_WIDGET (canvas));
/* By default, we use the style background. */
gdk_gc_set_foreground (canvas->pixmap_gc,
&style->bg[GTK_STATE_NORMAL]);
gdk_draw_rectangle (drawable,
canvas->pixmap_gc,
TRUE,
0, 0,
width, height);
}
static void
do_update (GnomeCanvas *canvas)
{
/* Cause the update if necessary */
update_again:
if (canvas->need_update) {
cairo_matrix_t w2c;
/* We start updating root with w2c matrix */
gnome_canvas_w2c_matrix (canvas, &w2c);
gnome_canvas_item_invoke_update (canvas->root, &w2c, 0);
canvas->need_update = FALSE;
}
/* Pick new current item */
while (canvas->need_repick) {
canvas->need_repick = FALSE;
pick_current_item (canvas, &canvas->pick_event);
}
/* it is possible that during picking we emitted an event in which
the user then called some function which then requested update
of something. Without this we'd be left in a state where
need_update would have been left TRUE and the canvas would have
been left unpainted. */
if (canvas->need_update) {
goto update_again;
}
}
/* Idle handler for the canvas. It deals with pending updates and redraws. */
static gboolean
idle_handler (gpointer data)
{
GnomeCanvas *canvas;
GDK_THREADS_ENTER ();
canvas = GNOME_CANVAS (data);
do_update (canvas);
/* Reset idle id */
canvas->idle_id = 0;
GDK_THREADS_LEAVE ();
return FALSE;
}
/* Convenience function to add an idle handler to a canvas */
static void
add_idle (GnomeCanvas *canvas)
{
g_assert (canvas->need_update);
if (!canvas->idle_id)
canvas->idle_id = g_idle_add_full (CANVAS_IDLE_PRIORITY,
idle_handler,
canvas,
NULL);
/* canvas->idle_id = gtk_idle_add (idle_handler, canvas); */
}
/**
* gnome_canvas_root:
* @canvas: A canvas.
*
* Queries the root group of a canvas.
*
* Return value: The root group of the specified canvas.
**/
GnomeCanvasGroup *
gnome_canvas_root (GnomeCanvas *canvas)
{
g_return_val_if_fail (GNOME_IS_CANVAS (canvas), NULL);
return GNOME_CANVAS_GROUP (canvas->root);
}
/**
* gnome_canvas_set_scroll_region:
* @canvas: A canvas.
* @x1: Leftmost limit of the scrolling region.
* @y1: Upper limit of the scrolling region.
* @x2: Rightmost limit of the scrolling region.
* @y2: Lower limit of the scrolling region.
*
* Sets the scrolling region of a canvas to the specified rectangle. The canvas
* will then be able to scroll only within this region. The view of the canvas
* is adjusted as appropriate to display as much of the new region as possible.
**/
void
gnome_canvas_set_scroll_region (GnomeCanvas *canvas,
gdouble x1,
gdouble y1,
gdouble x2,
gdouble y2)
{
GtkLayout *layout;
GtkAdjustment *hadjustment;
GtkAdjustment *vadjustment;
gdouble hadjustment_value;
gdouble vadjustment_value;
gdouble wxofs, wyofs;
gint xofs, yofs;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
layout = GTK_LAYOUT (canvas);
hadjustment = gtk_layout_get_hadjustment (layout);
vadjustment = gtk_layout_get_vadjustment (layout);
hadjustment_value = gtk_adjustment_get_value (hadjustment);
vadjustment_value = gtk_adjustment_get_value (vadjustment);
/*
* Set the new scrolling region. If possible, do not move the visible contents of the
* canvas.
*/
gnome_canvas_c2w (canvas,
hadjustment_value + canvas->zoom_xofs,
vadjustment_value + canvas->zoom_yofs,
/*canvas->zoom_xofs,
canvas->zoom_yofs,*/
&wxofs, &wyofs);
canvas->scroll_x1 = x1;
canvas->scroll_y1 = y1;
canvas->scroll_x2 = x2;
canvas->scroll_y2 = y2;
gnome_canvas_w2c (canvas, wxofs, wyofs, &xofs, &yofs);
scroll_to (canvas, xofs, yofs);
canvas->need_repick = TRUE;
#if 0
/* todo: should be requesting update */
(* GNOME_CANVAS_ITEM_CLASS (canvas->root->object.klass)->update) (
canvas->root, NULL, NULL, 0);
#endif
}
/**
* gnome_canvas_get_scroll_region:
* @canvas: A canvas.
* @x1: Leftmost limit of the scrolling region (return value).
* @y1: Upper limit of the scrolling region (return value).
* @x2: Rightmost limit of the scrolling region (return value).
* @y2: Lower limit of the scrolling region (return value).
*
* Queries the scrolling region of a canvas.
**/
void
gnome_canvas_get_scroll_region (GnomeCanvas *canvas,
gdouble *x1,
gdouble *y1,
gdouble *x2,
gdouble *y2)
{
g_return_if_fail (GNOME_IS_CANVAS (canvas));
if (x1)
*x1 = canvas->scroll_x1;
if (y1)
*y1 = canvas->scroll_y1;
if (x2)
*x2 = canvas->scroll_x2;
if (y2)
*y2 = canvas->scroll_y2;
}
/**
* gnome_canvas_set_center_scroll_region:
* @canvas: A canvas.
* @center_scroll_region: Whether to center the scrolling region in the canvas
* window when it is smaller than the canvas' allocation.
*
* When the scrolling region of the canvas is smaller than the canvas window,
* e.g. the allocation of the canvas, it can be either centered on the window
* or simply made to be on the upper-left corner on the window. This function
* lets you configure this property.
**/
void
gnome_canvas_set_center_scroll_region (GnomeCanvas *canvas,
gboolean center_scroll_region)
{
GtkLayout *layout;
GtkAdjustment *hadjustment;
GtkAdjustment *vadjustment;
gdouble hadjustment_value;
gdouble vadjustment_value;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
layout = GTK_LAYOUT (canvas);
hadjustment = gtk_layout_get_hadjustment (layout);
vadjustment = gtk_layout_get_vadjustment (layout);
hadjustment_value = gtk_adjustment_get_value (hadjustment);
vadjustment_value = gtk_adjustment_get_value (vadjustment);
canvas->center_scroll_region = center_scroll_region != 0;
scroll_to (canvas, hadjustment_value, vadjustment_value);
}
/**
* gnome_canvas_get_center_scroll_region:
* @canvas: A canvas.
*
* Returns whether the canvas is set to center the scrolling region in the window
* if the former is smaller than the canvas' allocation.
*
* Return value: Whether the scroll region is being centered in the canvas window.
**/
gboolean
gnome_canvas_get_center_scroll_region (GnomeCanvas *canvas)
{
g_return_val_if_fail (GNOME_IS_CANVAS (canvas), FALSE);
return canvas->center_scroll_region ? TRUE : FALSE;
}
/**
* gnome_canvas_set_pixels_per_unit:
* @canvas: A canvas.
* @n: The number of pixels that correspond to one canvas unit.
*
* Sets the zooming factor of a canvas by specifying the number of pixels that
* correspond to one canvas unit.
*
* The anchor point for zooming, i.e. the point that stays fixed and all others
* zoom inwards or outwards from it, depends on whether the canvas is set to
* center the scrolling region or not. You can control this using the
* gnome_canvas_set_center_scroll_region() function. If the canvas is set to
* center the scroll region, then the center of the canvas window is used as the
* anchor point for zooming. Otherwise, the upper-left corner of the canvas
* window is used as the anchor point.
**/
void
gnome_canvas_set_pixels_per_unit (GnomeCanvas *canvas, gdouble n)
{
GtkLayout *layout;
GtkAdjustment *hadjustment;
GtkAdjustment *vadjustment;
gdouble ax, ay;
gint x1, y1;
gint anchor_x, anchor_y;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
g_return_if_fail (n > GNOME_CANVAS_EPSILON);
layout = GTK_LAYOUT (canvas);
hadjustment = gtk_layout_get_hadjustment (layout);
vadjustment = gtk_layout_get_vadjustment (layout);
if (canvas->center_scroll_region) {
GtkAllocation allocation;
gtk_widget_get_allocation (GTK_WIDGET (canvas), &allocation);
anchor_x = allocation.width / 2;
anchor_y = allocation.height / 2;
} else
anchor_x = anchor_y = 0;
/* Find the coordinates of the anchor point in units. */
if (hadjustment) {
gdouble value = gtk_adjustment_get_value (hadjustment);
ax = (value + anchor_x) / canvas->pixels_per_unit +
canvas->scroll_x1 + canvas->zoom_xofs;
} else {
ax = (0.0 + anchor_x) / canvas->pixels_per_unit +
canvas->scroll_x1 + canvas->zoom_xofs;
}
if (vadjustment) {
gdouble value = gtk_adjustment_get_value (vadjustment);
ay = (value + anchor_y) / canvas->pixels_per_unit +
canvas->scroll_y1 + canvas->zoom_yofs;
} else {
ay = (0.0 + anchor_y) / canvas->pixels_per_unit +
canvas->scroll_y1 + canvas->zoom_yofs;
}
/* Now calculate the new offset of the upper left corner. */
x1 = ((ax - canvas->scroll_x1) * n) - anchor_x;
y1 = ((ay - canvas->scroll_y1) * n) - anchor_y;
canvas->pixels_per_unit = n;
scroll_to (canvas, x1, y1);
if (!(canvas->root->flags & GNOME_CANVAS_ITEM_NEED_AFFINE)) {
canvas->root->flags |= GNOME_CANVAS_ITEM_NEED_AFFINE;
gnome_canvas_request_update (canvas);
}
canvas->need_repick = TRUE;
}
/**
* gnome_canvas_scroll_to:
* @canvas: A canvas.
* @cx: Horizontal scrolling offset in canvas pixel units.
* @cy: Vertical scrolling offset in canvas pixel units.
*
* Makes a canvas scroll to the specified offsets, given in canvas pixel units.
* The canvas will adjust the view so that it is not outside the scrolling
* region. This function is typically not used, as it is better to hook
* scrollbars to the canvas layout's scrolling adjusments.
**/
void
gnome_canvas_scroll_to (GnomeCanvas *canvas, gint cx, gint cy)
{
g_return_if_fail (GNOME_IS_CANVAS (canvas));
scroll_to (canvas, cx, cy);
}
/**
* gnome_canvas_get_scroll_offsets:
* @canvas: A canvas.
* @cx: Horizontal scrolling offset (return value).
* @cy: Vertical scrolling offset (return value).
*
* Queries the scrolling offsets of a canvas. The values are returned in canvas
* pixel units.
**/
void
gnome_canvas_get_scroll_offsets (GnomeCanvas *canvas, gint *cx, gint *cy)
{
GtkLayout *layout;
GtkAdjustment *adjustment;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
layout = GTK_LAYOUT (canvas);
if (cx) {
adjustment = gtk_layout_get_hadjustment (layout);
*cx = (gint) gtk_adjustment_get_value (adjustment);
}
if (cy) {
adjustment = gtk_layout_get_vadjustment (layout);
*cy = (gint) gtk_adjustment_get_value (adjustment);
}
}
/**
* gnome_canvas_get_item_at:
* @canvas: A canvas.
* @x: X position in world coordinates.
* @y: Y position in world coordinates.
*
* Looks for the item that is under the specified position, which must be
* specified in world coordinates.
*
* Return value: The sought item, or NULL if no item is at the specified
* coordinates.
**/
GnomeCanvasItem *
gnome_canvas_get_item_at (GnomeCanvas *canvas, gdouble x, gdouble y)
{
gint cx, cy;
g_return_val_if_fail (GNOME_IS_CANVAS (canvas), NULL);
gnome_canvas_w2c (canvas, x, y, &cx, &cy);
return gnome_canvas_item_invoke_point (canvas->root, x, y, cx, cy);
}
/* Queues an update of the canvas */
static void
gnome_canvas_request_update (GnomeCanvas *canvas)
{
GNOME_CANVAS_GET_CLASS (canvas)->request_update (canvas);
}
static void
gnome_canvas_request_update_real (GnomeCanvas *canvas)
{
if (canvas->need_update)
return;
canvas->need_update = TRUE;
if (gtk_widget_get_mapped ((GtkWidget *) canvas))
add_idle (canvas);
}
static inline void
get_visible_rect (GnomeCanvas *canvas, GdkRectangle *visible)
{
GtkLayout *layout;
GtkAllocation allocation;
GtkAdjustment *hadjustment;
GtkAdjustment *vadjustment;
gdouble hadjustment_value;
gdouble vadjustment_value;
gtk_widget_get_allocation (GTK_WIDGET (canvas), &allocation);
layout = GTK_LAYOUT (canvas);
hadjustment = gtk_layout_get_hadjustment (layout);
vadjustment = gtk_layout_get_vadjustment (layout);
hadjustment_value = gtk_adjustment_get_value (hadjustment);
vadjustment_value = gtk_adjustment_get_value (vadjustment);
visible->x = hadjustment_value - canvas->zoom_xofs;
visible->y = vadjustment_value - canvas->zoom_yofs;
visible->width = allocation.width;
visible->height = allocation.height;
}
/**
* gnome_canvas_request_redraw:
* @canvas: A canvas.
* @x1: Leftmost coordinate of the rectangle to be redrawn.
* @y1: Upper coordinate of the rectangle to be redrawn.
* @x2: Rightmost coordinate of the rectangle to be redrawn, plus 1.
* @y2: Lower coordinate of the rectangle to be redrawn, plus 1.
*
* Convenience function that informs a canvas that the specified rectangle needs
* to be repainted. The rectangle includes @x1 and @y1, but not @x2 and @y2. To
* be used only by item implementations.
**/
void
gnome_canvas_request_redraw (GnomeCanvas *canvas, gint x1, gint y1, gint x2, gint y2)
{
GdkRectangle area, clip;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
if (!gtk_widget_is_drawable (GTK_WIDGET (canvas)) || (x1 >= x2) || (y1 >= y2))
return;
area.x = x1;
area.y = y1;
area.width = x2 - x1;
area.height = y2 - y1;
get_visible_rect (canvas, &clip);
if (!gdk_rectangle_intersect (&area, &clip, &area))
return;
gdk_window_invalidate_rect (gtk_layout_get_bin_window (GTK_LAYOUT (canvas)),
&area, FALSE);
}
/**
* gnome_canvas_w2c_matrix:
* @canvas: A canvas.
* @matrix: (out): matrix to initialize
*
* Gets the transformtion matrix that converts from world coordinates to canvas
* pixel coordinates.
**/
void
gnome_canvas_w2c_matrix (GnomeCanvas *canvas, cairo_matrix_t *matrix)
{
g_return_if_fail (GNOME_IS_CANVAS (canvas));
g_return_if_fail (matrix != NULL);
cairo_matrix_init_scale (matrix,
canvas->pixels_per_unit,
canvas->pixels_per_unit);
cairo_matrix_translate (matrix,
-canvas->scroll_x1,
-canvas->scroll_y1);
}
/**
* gnome_canvas_c2w_matrix:
* @canvas: A canvas.
* @matrix: (out): matrix to initialize
*
* Gets the transformtion matrix that converts from canvas pixel coordinates to
* world coordinates.
**/
void
gnome_canvas_c2w_matrix (GnomeCanvas *canvas, cairo_matrix_t *matrix)
{
g_return_if_fail (GNOME_IS_CANVAS (canvas));
g_return_if_fail (matrix != NULL);
cairo_matrix_init_translate (matrix,
canvas->scroll_x1,
canvas->scroll_y1);
cairo_matrix_scale (matrix,
1 / canvas->pixels_per_unit,
1 / canvas->pixels_per_unit);
}
/**
* gnome_canvas_w2c:
* @canvas: A canvas.
* @wx: World X coordinate.
* @wy: World Y coordinate.
* @cx: X pixel coordinate (return value).
* @cy: Y pixel coordinate (return value).
*
* Converts world coordinates into canvas pixel coordinates.
**/
void
gnome_canvas_w2c (GnomeCanvas *canvas, gdouble wx, gdouble wy, gint *cx, gint *cy)
{
cairo_matrix_t w2c;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
gnome_canvas_w2c_matrix (canvas, &w2c);
cairo_matrix_transform_point (&w2c, &wx, &wy);
if (cx)
*cx = floor (wx + 0.5);
if (cy)
*cy = floor (wy + 0.5);
}
/**
* gnome_canvas_w2c_d:
* @canvas: A canvas.
* @wx: World X coordinate.
* @wy: World Y coordinate.
* @cx: X pixel coordinate (return value).
* @cy: Y pixel coordinate (return value).
*
* Converts world coordinates into canvas pixel coordinates. This
* version returns coordinates in floating point coordinates, for
* greater precision.
**/
void
gnome_canvas_w2c_d (GnomeCanvas *canvas,
gdouble wx,
gdouble wy,
gdouble *cx,
gdouble *cy)
{
cairo_matrix_t w2c;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
gnome_canvas_w2c_matrix (canvas, &w2c);
cairo_matrix_transform_point (&w2c, &wx, &wy);
if (cx)
*cx = wx;
if (cy)
*cy = wy;
}
/**
* gnome_canvas_c2w:
* @canvas: A canvas.
* @cx: Canvas pixel X coordinate.
* @cy: Canvas pixel Y coordinate.
* @wx: X world coordinate (return value).
* @wy: Y world coordinate (return value).
*
* Converts canvas pixel coordinates to world coordinates.
**/
void
gnome_canvas_c2w (GnomeCanvas *canvas, gint cx, gint cy, gdouble *wx, gdouble *wy)
{
cairo_matrix_t c2w;
double x, y;
g_return_if_fail (GNOME_IS_CANVAS (canvas));
x = cx;
y = cy;
gnome_canvas_c2w_matrix (canvas, &c2w);
cairo_matrix_transform_point (&c2w, &x, &y);
if (wx)
*wx = x;
if (wy)
*wy = y;
}
/**
* gnome_canvas_window_to_world:
* @canvas: A canvas.
* @winx: Window-relative X coordinate.
* @winy: Window-relative Y coordinate.
* @worldx: X world coordinate (return value).
* @worldy: Y world coordinate (return value).
*
* Converts window-relative coordinates into world coordinates. You can use
* this when you need to convert mouse coordinates into world coordinates, for
* example.
**/
void
gnome_canvas_window_to_world (GnomeCanvas *canvas, gdouble winx, gdouble winy,
gdouble *worldx, gdouble *worldy)
{
g_return_if_fail (GNOME_IS_CANVAS (canvas));
if (worldx)
*worldx = canvas->scroll_x1 + ((winx - canvas->zoom_xofs)
/ canvas->pixels_per_unit);
if (worldy)
*worldy = canvas->scroll_y1 + ((winy - canvas->zoom_yofs)
/ canvas->pixels_per_unit);
}
/**
* gnome_canvas_world_to_window:
* @canvas: A canvas.
* @worldx: World X coordinate.
* @worldy: World Y coordinate.
* @winx: X window-relative coordinate.
* @winy: Y window-relative coordinate.
*
* Converts world coordinates into window-relative coordinates.
**/
void
gnome_canvas_world_to_window (GnomeCanvas *canvas, gdouble worldx, gdouble worldy,
gdouble *winx, gdouble *winy)
{
g_return_if_fail (GNOME_IS_CANVAS (canvas));
if (winx)
*winx = (canvas->pixels_per_unit)*(worldx - canvas->scroll_x1) + canvas->zoom_xofs;
if (winy)
*winy = (canvas->pixels_per_unit)*(worldy - canvas->scroll_y1) + canvas->zoom_yofs;
}
/**
* gnome_canvas_get_color:
* @canvas: A canvas.
* @spec: X color specification, or NULL for "transparent".
* @color: Returns the allocated color.
*
* Allocates a color based on the specified X color specification. As a
* convenience to item implementations, it returns TRUE if the color was
* allocated, or FALSE if the specification was NULL. A NULL color
* specification is considered as "transparent" by the canvas.
*
* Return value: TRUE if @spec is non-NULL and the color is allocated. If @spec
* is NULL, then returns FALSE.
**/
gint
gnome_canvas_get_color (GnomeCanvas *canvas, const gchar *spec, GdkColor *color)
{
GdkColormap *colormap;
g_return_val_if_fail (GNOME_IS_CANVAS (canvas), FALSE);
g_return_val_if_fail (color != NULL, FALSE);
if (!spec) {
color->pixel = 0;
color->red = 0;
color->green = 0;
color->blue = 0;
return FALSE;
}
gdk_color_parse (spec, color);
colormap = gtk_widget_get_colormap (GTK_WIDGET (canvas));
gdk_rgb_find_color (colormap, color);
return TRUE;
}
/**
* gnome_canvas_get_color_pixel:
* @canvas: A canvas.
* @rgba: RGBA color specification.
*
* Allocates a color from the RGBA value passed into this function. The alpha
* opacity value is discarded, since normal X colors do not support it.
*
* Return value: Allocated pixel value corresponding to the specified color.
**/
gulong
gnome_canvas_get_color_pixel (GnomeCanvas *canvas, guint rgba)
{
GdkColormap *colormap;
GdkColor color;
g_return_val_if_fail (GNOME_IS_CANVAS (canvas), 0);
color.red = ((rgba & 0xff000000) >> 16) + ((rgba & 0xff000000) >> 24);
color.green = ((rgba & 0x00ff0000) >> 8) + ((rgba & 0x00ff0000) >> 16);
color.blue = (rgba & 0x0000ff00) + ((rgba & 0x0000ff00) >> 8);
color.pixel = 0;
colormap = gtk_widget_get_colormap (GTK_WIDGET (canvas));
gdk_rgb_find_color (colormap, &color);
return color.pixel;
}
static gboolean
boolean_handled_accumulator (GSignalInvocationHint *ihint,
GValue *return_accu,
const GValue *handler_return,
gpointer dummy)
{
gboolean continue_emission;
gboolean signal_handled;
signal_handled = g_value_get_boolean (handler_return);
g_value_set_boolean (return_accu, signal_handled);
continue_emission = !signal_handled;
return continue_emission;
}
/* Class initialization function for GnomeCanvasItemClass */
static void
gnome_canvas_item_class_init (GnomeCanvasItemClass *class)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass *) class;
item_parent_class = g_type_class_peek_parent (class);
gobject_class->set_property = gnome_canvas_item_set_property;
gobject_class->get_property = gnome_canvas_item_get_property;
g_object_class_install_property
(gobject_class, ITEM_PROP_PARENT,
g_param_spec_object ("parent", NULL, NULL,
GNOME_TYPE_CANVAS_ITEM,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
item_signals[ITEM_EVENT] =
g_signal_new ("event",
G_TYPE_FROM_CLASS (class),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GnomeCanvasItemClass, event),
boolean_handled_accumulator, NULL,
gnome_canvas_marshal_BOOLEAN__BOXED,
G_TYPE_BOOLEAN, 1,
GDK_TYPE_EVENT | G_SIGNAL_TYPE_STATIC_SCOPE);
gobject_class->dispose = gnome_canvas_item_dispose;
class->realize = gnome_canvas_item_realize;
class->unrealize = gnome_canvas_item_unrealize;
class->map = gnome_canvas_item_map;
class->unmap = gnome_canvas_item_unmap;
class->update = gnome_canvas_item_update;
}