Below are the code examples that are used in the above text which are not included in complete form elsewhere.
/* example-start tictactoe tictactoe.h */
/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This 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.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __TICTACTOE_H__
#define __TICTACTOE_H__
#include <gdk/gdk.h>
#include <gtk/gtkvbox.h>
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
#define TICTACTOE(obj) GTK_CHECK_CAST (obj, tictactoe_get_type (), Tictactoe)
#define TICTACTOE_CLASS(klass) GTK_CHECK_CLASS_CAST (klass, tictactoe_get_type (), TictactoeClass)
#define IS_TICTACTOE(obj) GTK_CHECK_TYPE (obj, tictactoe_get_type ())
typedef struct _Tictactoe Tictactoe;
typedef struct _TictactoeClass TictactoeClass;
struct _Tictactoe
{
GtkVBox vbox;
GtkWidget *buttons[3][3];
};
struct _TictactoeClass
{
GtkVBoxClass parent_class;
void (* tictactoe) (Tictactoe *ttt);
};
guint tictactoe_get_type (void);
GtkWidget* tictactoe_new (void);
void tictactoe_clear (Tictactoe *ttt);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __TICTACTOE_H__ */
/* example-end */
/* example-start tictactoe tictactoe.c */
/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This 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.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "gtk/gtksignal.h"
#include "gtk/gtktable.h"
#include "gtk/gtktogglebutton.h"
#include "tictactoe.h"
enum {
TICTACTOE_SIGNAL,
LAST_SIGNAL
};
static void tictactoe_class_init (TictactoeClass *klass);
static void tictactoe_init (Tictactoe *ttt);
static void tictactoe_toggle (GtkWidget *widget, Tictactoe *ttt);
static gint tictactoe_signals[LAST_SIGNAL] = { 0 };
guint
tictactoe_get_type ()
{
static guint ttt_type = 0;
if (!ttt_type)
{
GtkTypeInfo ttt_info =
{
"Tictactoe",
sizeof (Tictactoe),
sizeof (TictactoeClass),
(GtkClassInitFunc) tictactoe_class_init,
(GtkObjectInitFunc) tictactoe_init,
(GtkArgSetFunc) NULL,
(GtkArgGetFunc) NULL
};
ttt_type = gtk_type_unique (gtk_vbox_get_type (), &ttt_info);
}
return ttt_type;
}
static void
tictactoe_class_init (TictactoeClass *class)
{
GtkObjectClass *object_class;
object_class = (GtkObjectClass*) class;
tictactoe_signals[TICTACTOE_SIGNAL] = gtk_signal_new ("tictactoe",
GTK_RUN_FIRST,
object_class->type,
GTK_SIGNAL_OFFSET (TictactoeClass,
tictactoe),
gtk_signal_default_marshaller,
GTK_TYPE_NONE, 0);
gtk_object_class_add_signals (object_class, tictactoe_signals, LAST_SIGNAL);
class->tictactoe = NULL;
}
static void
tictactoe_init (Tictactoe *ttt)
{
GtkWidget *table;
gint i,j;
table = gtk_table_new (3, 3, TRUE);
gtk_container_add (GTK_CONTAINER(ttt), table);
gtk_widget_show (table);
for (i=0;i<3; i++)
for (j=0;j<3; j++)
{
ttt->buttons[i][j] = gtk_toggle_button_new ();
gtk_table_attach_defaults (GTK_TABLE(table), ttt->buttons[i][j],
i, i+1, j, j+1);
gtk_signal_connect (GTK_OBJECT (ttt->buttons[i][j]), "toggled",
GTK_SIGNAL_FUNC (tictactoe_toggle), ttt);
gtk_widget_set_usize (ttt->buttons[i][j], 20, 20);
gtk_widget_show (ttt->buttons[i][j]);
}
}
GtkWidget*
tictactoe_new ()
{
return GTK_WIDGET ( gtk_type_new (tictactoe_get_type ()));
}
void
tictactoe_clear (Tictactoe *ttt)
{
int i,j;
for (i=0;i<3;i++)
for (j=0;j<3;j++)
{
gtk_signal_handler_block_by_data (GTK_OBJECT(ttt->buttons[i][j]), ttt);
gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (ttt->buttons[i][j]),
FALSE);
gtk_signal_handler_unblock_by_data (GTK_OBJECT(ttt->buttons[i][j]), ttt);
}
}
static void
tictactoe_toggle (GtkWidget *widget, Tictactoe *ttt)
{
int i,k;
static int rwins[8][3] = { { 0, 0, 0 }, { 1, 1, 1 }, { 2, 2, 2 },
{ 0, 1, 2 }, { 0, 1, 2 }, { 0, 1, 2 },
{ 0, 1, 2 }, { 0, 1, 2 } };
static int cwins[8][3] = { { 0, 1, 2 }, { 0, 1, 2 }, { 0, 1, 2 },
{ 0, 0, 0 }, { 1, 1, 1 }, { 2, 2, 2 },
{ 0, 1, 2 }, { 2, 1, 0 } };
int success, found;
for (k=0; k<8; k++)
{
success = TRUE;
found = FALSE;
for (i=0;i<3;i++)
{
success = success &&
GTK_TOGGLE_BUTTON(ttt->buttons[rwins[k][i]][cwins[k][i]])->active;
found = found ||
ttt->buttons[rwins[k][i]][cwins[k][i]] == widget;
}
if (success && found)
{
gtk_signal_emit (GTK_OBJECT (ttt),
tictactoe_signals[TICTACTOE_SIGNAL]);
break;
}
}
}
/* example-end */
/* example-start tictactoe ttt_test.c */
#include <gtk/gtk.h>
#include "tictactoe.h"
void
win (GtkWidget *widget, gpointer data)
{
g_print ("Yay!\n");
tictactoe_clear (TICTACTOE (widget));
}
int
main (int argc, char *argv[])
{
GtkWidget *window;
GtkWidget *ttt;
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "Aspect Frame");
gtk_signal_connect (GTK_OBJECT (window), "destroy",
GTK_SIGNAL_FUNC (gtk_exit), NULL);
gtk_container_set_border_width (GTK_CONTAINER (window), 10);
ttt = tictactoe_new ();
gtk_container_add (GTK_CONTAINER (window), ttt);
gtk_widget_show (ttt);
gtk_signal_connect (GTK_OBJECT (ttt), "tictactoe",
GTK_SIGNAL_FUNC (win), NULL);
gtk_widget_show (window);
gtk_main ();
return 0;
}
/* example-end */
/* example-start gtkdial gtkdial.h */
/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This 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.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GTK_DIAL_H__
#define __GTK_DIAL_H__
#include <gdk/gdk.h>
#include <gtk/gtkadjustment.h>
#include <gtk/gtkwidget.h>
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
#define GTK_DIAL(obj) GTK_CHECK_CAST (obj, gtk_dial_get_type (), GtkDial)
#define GTK_DIAL_CLASS(klass) GTK_CHECK_CLASS_CAST (klass, gtk_dial_get_type (), GtkDialClass)
#define GTK_IS_DIAL(obj) GTK_CHECK_TYPE (obj, gtk_dial_get_type ())
typedef struct _GtkDial GtkDial;
typedef struct _GtkDialClass GtkDialClass;
struct _GtkDial
{
GtkWidget widget;
/* update policy (GTK_UPDATE_[CONTINUOUS/DELAYED/DISCONTINUOUS]) */
guint policy : 2;
/* Button currently pressed or 0 if none */
guint8 button;
/* Dimensions of dial components */
gint radius;
gint pointer_width;
/* ID of update timer, or 0 if none */
guint32 timer;
/* Current angle */
gfloat angle;
/* Old values from adjustment stored so we know when something changes */
gfloat old_value;
gfloat old_lower;
gfloat old_upper;
/* The adjustment object that stores the data for this dial */
GtkAdjustment *adjustment;
};
struct _GtkDialClass
{
GtkWidgetClass parent_class;
};
GtkWidget* gtk_dial_new (GtkAdjustment *adjustment);
guint gtk_dial_get_type (void);
GtkAdjustment* gtk_dial_get_adjustment (GtkDial *dial);
void gtk_dial_set_update_policy (GtkDial *dial,
GtkUpdateType policy);
void gtk_dial_set_adjustment (GtkDial *dial,
GtkAdjustment *adjustment);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __GTK_DIAL_H__ */
/* example-end */
/* example-start gtkdial gtkdial.c */
/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This 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.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <math.h>
#include <stdio.h>
#include <gtk/gtkmain.h>
#include <gtk/gtksignal.h>
#include "gtkdial.h"
#define SCROLL_DELAY_LENGTH 300
#define DIAL_DEFAULT_SIZE 100
/* Forward declarations */
static void gtk_dial_class_init (GtkDialClass *klass);
static void gtk_dial_init (GtkDial *dial);
static void gtk_dial_destroy (GtkObject *object);
static void gtk_dial_realize (GtkWidget *widget);
static void gtk_dial_size_request (GtkWidget *widget,
GtkRequisition *requisition);
static void gtk_dial_size_allocate (GtkWidget *widget,
GtkAllocation *allocation);
static gint gtk_dial_expose (GtkWidget *widget,
GdkEventExpose *event);
static gint gtk_dial_button_press (GtkWidget *widget,
GdkEventButton *event);
static gint gtk_dial_button_release (GtkWidget *widget,
GdkEventButton *event);
static gint gtk_dial_motion_notify (GtkWidget *widget,
GdkEventMotion *event);
static gint gtk_dial_timer (GtkDial *dial);
static void gtk_dial_update_mouse (GtkDial *dial, gint x, gint y);
static void gtk_dial_update (GtkDial *dial);
static void gtk_dial_adjustment_changed (GtkAdjustment *adjustment,
gpointer data);
static void gtk_dial_adjustment_value_changed (GtkAdjustment *adjustment,
gpointer data);
/* Local data */
static GtkWidgetClass *parent_class = NULL;
guint
gtk_dial_get_type ()
{
static guint dial_type = 0;
if (!dial_type)
{
GtkTypeInfo dial_info =
{
"GtkDial",
sizeof (GtkDial),
sizeof (GtkDialClass),
(GtkClassInitFunc) gtk_dial_class_init,
(GtkObjectInitFunc) gtk_dial_init,
(GtkArgSetFunc) NULL,
(GtkArgGetFunc) NULL,
};
dial_type = gtk_type_unique (gtk_widget_get_type (), &dial_info);
}
return dial_type;
}
static void
gtk_dial_class_init (GtkDialClass *class)
{
GtkObjectClass *object_class;
GtkWidgetClass *widget_class;
object_class = (GtkObjectClass*) class;
widget_class = (GtkWidgetClass*) class;
parent_class = gtk_type_class (gtk_widget_get_type ());
object_class->destroy = gtk_dial_destroy;
widget_class->realize = gtk_dial_realize;
widget_class->expose_event = gtk_dial_expose;
widget_class->size_request = gtk_dial_size_request;
widget_class->size_allocate = gtk_dial_size_allocate;
widget_class->button_press_event = gtk_dial_button_press;
widget_class->button_release_event = gtk_dial_button_release;
widget_class->motion_notify_event = gtk_dial_motion_notify;
}
static void
gtk_dial_init (GtkDial *dial)
{
dial->button = 0;
dial->policy = GTK_UPDATE_CONTINUOUS;
dial->timer = 0;
dial->radius = 0;
dial->pointer_width = 0;
dial->angle = 0.0;
dial->old_value = 0.0;
dial->old_lower = 0.0;
dial->old_upper = 0.0;
dial->adjustment = NULL;
}
GtkWidget*
gtk_dial_new (GtkAdjustment *adjustment)
{
GtkDial *dial;
dial = gtk_type_new (gtk_dial_get_type ());
if (!adjustment)
adjustment = (GtkAdjustment*) gtk_adjustment_new (0.0, 0.0, 0.0,
0.0, 0.0, 0.0);
gtk_dial_set_adjustment (dial, adjustment);
return GTK_WIDGET (dial);
}
static void
gtk_dial_destroy (GtkObject *object)
{
GtkDial *dial;
g_return_if_fail (object != NULL);
g_return_if_fail (GTK_IS_DIAL (object));
dial = GTK_DIAL (object);
if (dial->adjustment)
gtk_object_unref (GTK_OBJECT (dial->adjustment));
if (GTK_OBJECT_CLASS (parent_class)->destroy)
(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
}
GtkAdjustment*
gtk_dial_get_adjustment (GtkDial *dial)
{
g_return_val_if_fail (dial != NULL, NULL);
g_return_val_if_fail (GTK_IS_DIAL (dial), NULL);
return dial->adjustment;
}
void
gtk_dial_set_update_policy (GtkDial *dial,
GtkUpdateType policy)
{
g_return_if_fail (dial != NULL);
g_return_if_fail (GTK_IS_DIAL (dial));
dial->policy = policy;
}
void
gtk_dial_set_adjustment (GtkDial *dial,
GtkAdjustment *adjustment)
{
g_return_if_fail (dial != NULL);
g_return_if_fail (GTK_IS_DIAL (dial));
if (dial->adjustment)
{
gtk_signal_disconnect_by_data (GTK_OBJECT (dial->adjustment),
(gpointer) dial);
gtk_object_unref (GTK_OBJECT (dial->adjustment));
}
dial->adjustment = adjustment;
gtk_object_ref (GTK_OBJECT (dial->adjustment));
gtk_signal_connect (GTK_OBJECT (adjustment), "changed",
(GtkSignalFunc) gtk_dial_adjustment_changed,
(gpointer) dial);
gtk_signal_connect (GTK_OBJECT (adjustment), "value_changed",
(GtkSignalFunc) gtk_dial_adjustment_value_changed,
(gpointer) dial);
dial->old_value = adjustment->value;
dial->old_lower = adjustment->lower;
dial->old_upper = adjustment->upper;
gtk_dial_update (dial);
}
static void
gtk_dial_realize (GtkWidget *widget)
{
GtkDial *dial;
GdkWindowAttr attributes;
gint attributes_mask;
g_return_if_fail (widget != NULL);
g_return_if_fail (GTK_IS_DIAL (widget));
GTK_WIDGET_SET_FLAGS (widget, GTK_REALIZED);
dial = GTK_DIAL (widget);
attributes.x = widget->allocation.x;
attributes.y = widget->allocation.y;
attributes.width = widget->allocation.width;
attributes.height = widget->allocation.height;
attributes.wclass = GDK_INPUT_OUTPUT;
attributes.window_type = GDK_WINDOW_CHILD;
attributes.event_mask = gtk_widget_get_events (widget) |
GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK |
GDK_BUTTON_RELEASE_MASK | GDK_POINTER_MOTION_MASK |
GDK_POINTER_MOTION_HINT_MASK;
attributes.visual = gtk_widget_get_visual (widget);
attributes.colormap = gtk_widget_get_colormap (widget);
attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP;
widget->window = gdk_window_new (widget->parent->window,
&attributes,
attributes_mask);
widget->style = gtk_style_attach (widget->style, widget->window);
gdk_window_set_user_data (widget->window, widget);
gtk_style_set_background (widget->style, widget->window, GTK_STATE_ACTIVE);
}
static void
gtk_dial_size_request (GtkWidget *widget,
GtkRequisition *requisition)
{
requisition->width = DIAL_DEFAULT_SIZE;
requisition->height = DIAL_DEFAULT_SIZE;
}
static void
gtk_dial_size_allocate (GtkWidget *widget,
GtkAllocation *allocation)
{
GtkDial *dial;
g_return_if_fail (widget != NULL);
g_return_if_fail (GTK_IS_DIAL (widget));
g_return_if_fail (allocation != NULL);
widget->allocation = *allocation;
dial = GTK_DIAL (widget);
if (GTK_WIDGET_REALIZED (widget))
{
gdk_window_move_resize (widget->window,
allocation->x, allocation->y,
allocation->width, allocation->height);
}
dial->radius = MIN(allocation->width,allocation->height) * 0.45;
dial->pointer_width = dial->radius / 5;
}
static gint
gtk_dial_expose (GtkWidget *widget,
GdkEventExpose *event)
{
GtkDial *dial;
GdkPoint points[3];
gdouble s,c;
gdouble theta;
gint xc, yc;
gint tick_length;
gint i;
g_return_val_if_fail (widget != NULL, FALSE);
g_return_val_if_fail (GTK_IS_DIAL (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
if (event->count > 0)
return FALSE;
dial = GTK_DIAL (widget);
gdk_window_clear_area (widget->window,
0, 0,
widget->allocation.width,
widget->allocation.height);
xc = widget->allocation.width/2;
yc = widget->allocation.height/2;
/* Draw ticks */
for (i=0; i<25; i++)
{
theta = (i*M_PI/18. - M_PI/6.);
s = sin(theta);
c = cos(theta);
tick_length = (i%6 == 0) ? dial->pointer_width : dial->pointer_width/2;
gdk_draw_line (widget->window,
widget->style->fg_gc[widget->state],
xc + c*(dial->radius - tick_length),
yc - s*(dial->radius - tick_length),
xc + c*dial->radius,
yc - s*dial->radius);
}
/* Draw pointer */
s = sin(dial->angle);
c = cos(dial->angle);
points[0].x = xc + s*dial->pointer_width/2;
points[0].y = yc + c*dial->pointer_width/2;
points[1].x = xc + c*dial->radius;
points[1].y = yc - s*dial->radius;
points[2].x = xc - s*dial->pointer_width/2;
points[2].y = yc - c*dial->pointer_width/2;
gtk_draw_polygon (widget->style,
widget->window,
GTK_STATE_NORMAL,
GTK_SHADOW_OUT,
points, 3,
TRUE);
return FALSE;
}
static gint
gtk_dial_button_press (GtkWidget *widget,
GdkEventButton *event)
{
GtkDial *dial;
gint dx, dy;
double s, c;
double d_parallel;
double d_perpendicular;
g_return_val_if_fail (widget != NULL, FALSE);
g_return_val_if_fail (GTK_IS_DIAL (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
dial = GTK_DIAL (widget);
/* Determine if button press was within pointer region - we
do this by computing the parallel and perpendicular distance of
the point where the mouse was pressed from the line passing through
the pointer */
dx = event->x - widget->allocation.width / 2;
dy = widget->allocation.height / 2 - event->y;
s = sin(dial->angle);
c = cos(dial->angle);
d_parallel = s*dy + c*dx;
d_perpendicular = fabs(s*dx - c*dy);
if (!dial->button &&
(d_perpendicular < dial->pointer_width/2) &&
(d_parallel > - dial->pointer_width))
{
gtk_grab_add (widget);
dial->button = event->button;
gtk_dial_update_mouse (dial, event->x, event->y);
}
return FALSE;
}
static gint
gtk_dial_button_release (GtkWidget *widget,
GdkEventButton *event)
{
GtkDial *dial;
g_return_val_if_fail (widget != NULL, FALSE);
g_return_val_if_fail (GTK_IS_DIAL (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
dial = GTK_DIAL (widget);
if (dial->button == event->button)
{
gtk_grab_remove (widget);
dial->button = 0;
if (dial->policy == GTK_UPDATE_DELAYED)
gtk_timeout_remove (dial->timer);
if ((dial->policy != GTK_UPDATE_CONTINUOUS) &&
(dial->old_value != dial->adjustment->value))
gtk_signal_emit_by_name (GTK_OBJECT (dial->adjustment),
"value_changed");
}
return FALSE;
}
static gint
gtk_dial_motion_notify (GtkWidget *widget,
GdkEventMotion *event)
{
GtkDial *dial;
GdkModifierType mods;
gint x, y, mask;
g_return_val_if_fail (widget != NULL, FALSE);
g_return_val_if_fail (GTK_IS_DIAL (widget), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
dial = GTK_DIAL (widget);
if (dial->button != 0)
{
x = event->x;
y = event->y;
if (event->is_hint || (event->window != widget->window))
gdk_window_get_pointer (widget->window, &x, &y, &mods);
switch (dial->button)
{
case 1:
mask = GDK_BUTTON1_MASK;
break;
case 2:
mask = GDK_BUTTON2_MASK;
break;
case 3:
mask = GDK_BUTTON3_MASK;
break;
default:
mask = 0;
break;
}
if (mods & mask)
gtk_dial_update_mouse (dial, x,y);
}
return FALSE;
}
static gint
gtk_dial_timer (GtkDial *dial)
{
g_return_val_if_fail (dial != NULL, FALSE);
g_return_val_if_fail (GTK_IS_DIAL (dial), FALSE);
if (dial->policy == GTK_UPDATE_DELAYED)
gtk_signal_emit_by_name (GTK_OBJECT (dial->adjustment),
"value_changed");
return FALSE;
}
static void
gtk_dial_update_mouse (GtkDial *dial, gint x, gint y)
{
gint xc, yc;
gfloat old_value;
g_return_if_fail (dial != NULL);
g_return_if_fail (GTK_IS_DIAL (dial));
xc = GTK_WIDGET(dial)->allocation.width / 2;
yc = GTK_WIDGET(dial)->allocation.height / 2;
old_value = dial->adjustment->value;
dial->angle = atan2(yc-y, x-xc);
if (dial->angle < -M_PI/2.)
dial->angle += 2*M_PI;
if (dial->angle < -M_PI/6)
dial->angle = -M_PI/6;
if (dial->angle > 7.*M_PI/6.)
dial->angle = 7.*M_PI/6.;
dial->adjustment->value = dial->adjustment->lower + (7.*M_PI/6 - dial->angle) *
(dial->adjustment->upper - dial->adjustment->lower) / (4.*M_PI/3.);
if (dial->adjustment->value != old_value)
{
if (dial->policy == GTK_UPDATE_CONTINUOUS)
{
gtk_signal_emit_by_name (GTK_OBJECT (dial->adjustment),
"value_changed");
}
else
{
gtk_widget_draw (GTK_WIDGET(dial), NULL);
if (dial->policy == GTK_UPDATE_DELAYED)
{
if (dial->timer)
gtk_timeout_remove (dial->timer);
dial->timer = gtk_timeout_add (SCROLL_DELAY_LENGTH,
(GtkFunction) gtk_dial_timer,
(gpointer) dial);
}
}
}
}
static void
gtk_dial_update (GtkDial *dial)
{
gfloat new_value;
g_return_if_fail (dial != NULL);
g_return_if_fail (GTK_IS_DIAL (dial));
new_value = dial->adjustment->value;
if (new_value < dial->adjustment->lower)
new_value = dial->adjustment->lower;
if (new_value > dial->adjustment->upper)
new_value = dial->adjustment->upper;
if (new_value != dial->adjustment->value)
{
dial->adjustment->value = new_value;
gtk_signal_emit_by_name (GTK_OBJECT (dial->adjustment), "value_changed");
}
dial->angle = 7.*M_PI/6. - (new_value - dial->adjustment->lower) *
4.*M_PI/3. /
(dial->adjustment->upper - dial->adjustment->lower);
gtk_widget_draw (GTK_WIDGET(dial), NULL);
}
static void
gtk_dial_adjustment_changed (GtkAdjustment *adjustment,
gpointer data)
{
GtkDial *dial;
g_return_if_fail (adjustment != NULL);
g_return_if_fail (data != NULL);
dial = GTK_DIAL (data);
if ((dial->old_value != adjustment->value) ||
(dial->old_lower != adjustment->lower) ||
(dial->old_upper != adjustment->upper))
{
gtk_dial_update (dial);
dial->old_value = adjustment->value;
dial->old_lower = adjustment->lower;
dial->old_upper = adjustment->upper;
}
}
static void
gtk_dial_adjustment_value_changed (GtkAdjustment *adjustment,
gpointer data)
{
GtkDial *dial;
g_return_if_fail (adjustment != NULL);
g_return_if_fail (data != NULL);
dial = GTK_DIAL (data);
if (dial->old_value != adjustment->value)
{
gtk_dial_update (dial);
dial->old_value = adjustment->value;
}
}
/* example-end */
/* example-start scribble-simple scribble-simple.c */
/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This 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.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <gtk/gtk.h>
/* Backing pixmap for drawing area */
static GdkPixmap *pixmap = NULL;
/* Create a new backing pixmap of the appropriate size */
static gint
configure_event (GtkWidget *widget, GdkEventConfigure *event)
{
if (pixmap)
gdk_pixmap_unref(pixmap);
pixmap = gdk_pixmap_new(widget->window,
widget->allocation.width,
widget->allocation.height,
-1);
gdk_draw_rectangle (pixmap,
widget->style->white_gc,
TRUE,
0, 0,
widget->allocation.width,
widget->allocation.height);
return TRUE;
}
/* Redraw the screen from the backing pixmap */
static gint
expose_event (GtkWidget *widget, GdkEventExpose *event)
{
gdk_draw_pixmap(widget->window,
widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
pixmap,
event->area.x, event->area.y,
event->area.x, event->area.y,
event->area.width, event->area.height);
return FALSE;
}
/* Draw a rectangle on the screen */
static void
draw_brush (GtkWidget *widget, gdouble x, gdouble y)
{
GdkRectangle update_rect;
update_rect.x = x - 5;
update_rect.y = y - 5;
update_rect.width = 10;
update_rect.height = 10;
gdk_draw_rectangle (pixmap,
widget->style->black_gc,
TRUE,
update_rect.x, update_rect.y,
update_rect.width, update_rect.height);
gtk_widget_draw (widget, &update_rect);
}
static gint
button_press_event (GtkWidget *widget, GdkEventButton *event)
{
if (event->button == 1 && pixmap != NULL)
draw_brush (widget, event->x, event->y);
return TRUE;
}
static gint
motion_notify_event (GtkWidget *widget, GdkEventMotion *event)
{
int x, y;
GdkModifierType state;
if (event->is_hint)
gdk_window_get_pointer (event->window, &x, &y, &state);
else
{
x = event->x;
y = event->y;
state = event->state;
}
if (state & GDK_BUTTON1_MASK && pixmap != NULL)
draw_brush (widget, x, y);
return TRUE;
}
void
quit ()
{
gtk_exit (0);
}
int
main (int argc, char *argv[])
{
GtkWidget *window;
GtkWidget *drawing_area;
GtkWidget *vbox;
GtkWidget *button;
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_widget_set_name (window, "Test Input");
vbox = gtk_vbox_new (FALSE, 0);
gtk_container_add (GTK_CONTAINER (window), vbox);
gtk_widget_show (vbox);
gtk_signal_connect (GTK_OBJECT (window), "destroy",
GTK_SIGNAL_FUNC (quit), NULL);
/* Create the drawing area */
drawing_area = gtk_drawing_area_new ();
gtk_drawing_area_size (GTK_DRAWING_AREA (drawing_area), 200, 200);
gtk_box_pack_start (GTK_BOX (vbox), drawing_area, TRUE, TRUE, 0);
gtk_widget_show (drawing_area);
/* Signals used to handle backing pixmap */
gtk_signal_connect (GTK_OBJECT (drawing_area), "expose_event",
(GtkSignalFunc) expose_event, NULL);
gtk_signal_connect (GTK_OBJECT(drawing_area),"configure_event",
(GtkSignalFunc) configure_event, NULL);
/* Event signals */
gtk_signal_connect (GTK_OBJECT (drawing_area), "motion_notify_event",
(GtkSignalFunc) motion_notify_event, NULL);
gtk_signal_connect (GTK_OBJECT (drawing_area), "button_press_event",
(GtkSignalFunc) button_press_event, NULL);
gtk_widget_set_events (drawing_area, GDK_EXPOSURE_MASK
| GDK_LEAVE_NOTIFY_MASK
| GDK_BUTTON_PRESS_MASK
| GDK_POINTER_MOTION_MASK
| GDK_POINTER_MOTION_HINT_MASK);
/* .. And a quit button */
button = gtk_button_new_with_label ("Quit");
gtk_box_pack_start (GTK_BOX (vbox), button, FALSE, FALSE, 0);
gtk_signal_connect_object (GTK_OBJECT (button), "clicked",
GTK_SIGNAL_FUNC (gtk_widget_destroy),
GTK_OBJECT (window));
gtk_widget_show (button);
gtk_widget_show (window);
gtk_main ();
return 0;
}
/* example-end */