gtk2/demos/gtk-demo/fontplane.c
Matthias Clasen 22e1827f84 Change the default value of GtkWidget:can-focus
Make widgets can-focus by default, and change the semantics
of can-focus to be recursive . If it is set to FALSE, focus
can not enter the widget or its descendents at all anymore.

This commit temporarily breaks focus behavior of widgets
that did not expect to receive focus.
2020-04-09 17:50:29 -04:00

286 lines
8.1 KiB
C

/* GTK - The GIMP Toolkit
* Copyright (C) 2012 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include "fontplane.h"
enum {
PROP_0,
PROP_WEIGHT_ADJUSTMENT,
PROP_WIDTH_ADJUSTMENT
};
G_DEFINE_TYPE (GtkFontPlane, gtk_font_plane, GTK_TYPE_WIDGET)
static double
adjustment_get_normalized_value (GtkAdjustment *adj)
{
return (gtk_adjustment_get_value (adj) - gtk_adjustment_get_lower (adj)) /
(gtk_adjustment_get_upper (adj) - gtk_adjustment_get_lower (adj));
}
static void
val_to_xy (GtkFontPlane *plane,
gint *x,
gint *y)
{
gdouble u, v;
gint width, height;
width = gtk_widget_get_allocated_width (GTK_WIDGET (plane));
height = gtk_widget_get_allocated_height (GTK_WIDGET (plane));
u = adjustment_get_normalized_value (plane->width_adj);
v = adjustment_get_normalized_value (plane->weight_adj);
*x = CLAMP (width * u, 0, width - 1);
*y = CLAMP (height * (1 - v), 0, height - 1);
}
static void
plane_snapshot (GtkWidget *widget,
GtkSnapshot *snapshot)
{
GtkFontPlane *plane = GTK_FONT_PLANE (widget);
gint x, y;
gint width, height;
cairo_t *cr;
val_to_xy (plane, &x, &y);
width = gtk_widget_get_allocated_width (widget);
height = gtk_widget_get_allocated_height (widget);
cr = gtk_snapshot_append_cairo (snapshot,
&GRAPHENE_RECT_INIT (0, 0, width, height));
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_rectangle (cr, 0, 0, width, height);
cairo_paint (cr);
cairo_move_to (cr, 0, y + 0.5);
cairo_line_to (cr, width, y + 0.5);
cairo_move_to (cr, x + 0.5, 0);
cairo_line_to (cr, x + 0.5, height);
if (gtk_widget_has_visible_focus (widget))
{
cairo_set_line_width (cr, 3.0);
cairo_set_source_rgba (cr, 1.0, 1.0, 1.0, 0.6);
cairo_stroke_preserve (cr);
cairo_set_line_width (cr, 1.0);
cairo_set_source_rgba (cr, 0.0, 0.0, 0.0, 0.8);
cairo_stroke (cr);
}
else
{
cairo_set_line_width (cr, 1.0);
cairo_set_source_rgba (cr, 0.8, 0.8, 0.8, 0.8);
cairo_stroke (cr);
}
cairo_destroy (cr);
}
static void
set_cross_cursor (GtkWidget *widget,
gboolean enabled)
{
if (enabled)
gtk_widget_set_cursor_from_name (widget, "crosshair");
else
gtk_widget_set_cursor (widget, NULL);
}
static void
adj_changed (GtkFontPlane *plane)
{
gtk_widget_queue_draw (GTK_WIDGET (plane));
}
static void
adjustment_set_normalized_value (GtkAdjustment *adj,
double val)
{
gtk_adjustment_set_value (adj,
gtk_adjustment_get_lower (adj) +
val * (gtk_adjustment_get_upper (adj) - gtk_adjustment_get_lower (adj)));
}
static void
update_value (GtkFontPlane *plane,
gint x,
gint y)
{
GtkWidget *widget = GTK_WIDGET (plane);
gdouble u, v;
u = CLAMP (x * (1.0 / gtk_widget_get_allocated_width (widget)), 0, 1);
v = CLAMP (1 - y * (1.0 / gtk_widget_get_allocated_height (widget)), 0, 1);
adjustment_set_normalized_value (plane->width_adj, u);
adjustment_set_normalized_value (plane->weight_adj, v);
gtk_widget_queue_draw (widget);
}
static void
plane_drag_gesture_begin (GtkGestureDrag *gesture,
gdouble start_x,
gdouble start_y,
GtkFontPlane *plane)
{
guint button;
button = gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture));
if (button != GDK_BUTTON_PRIMARY)
{
gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_DENIED);
return;
}
set_cross_cursor (GTK_WIDGET (plane), TRUE);
update_value (plane, start_x, start_y);
gtk_widget_grab_focus (GTK_WIDGET (plane));
gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_CLAIMED);
}
static void
plane_drag_gesture_update (GtkGestureDrag *gesture,
gdouble offset_x,
gdouble offset_y,
GtkFontPlane *plane)
{
gdouble start_x, start_y;
gtk_gesture_drag_get_start_point (GTK_GESTURE_DRAG (gesture),
&start_x, &start_y);
update_value (plane, start_x + offset_x, start_y + offset_y);
}
static void
plane_drag_gesture_end (GtkGestureDrag *gesture,
gdouble offset_x,
gdouble offset_y,
GtkFontPlane *plane)
{
set_cross_cursor (GTK_WIDGET (plane), FALSE);
}
static void
gtk_font_plane_init (GtkFontPlane *plane)
{
GtkGesture *gesture;
gesture = gtk_gesture_drag_new ();
g_signal_connect (gesture, "drag-begin",
G_CALLBACK (plane_drag_gesture_begin), plane);
g_signal_connect (gesture, "drag-update",
G_CALLBACK (plane_drag_gesture_update), plane);
g_signal_connect (gesture, "drag-end",
G_CALLBACK (plane_drag_gesture_end), plane);
gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (gesture), 0);
gtk_widget_add_controller (GTK_WIDGET (plane), GTK_EVENT_CONTROLLER (gesture));
}
static void
plane_finalize (GObject *object)
{
GtkFontPlane *plane = GTK_FONT_PLANE (object);
g_clear_object (&plane->weight_adj);
g_clear_object (&plane->width_adj);
G_OBJECT_CLASS (gtk_font_plane_parent_class)->finalize (object);
}
static void
plane_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
GtkFontPlane *plane = GTK_FONT_PLANE (object);
GtkAdjustment *adjustment;
switch (prop_id)
{
case PROP_WEIGHT_ADJUSTMENT:
adjustment = GTK_ADJUSTMENT (g_value_get_object (value));
if (adjustment)
{
plane->weight_adj = g_object_ref_sink (adjustment);
g_signal_connect_swapped (adjustment, "value-changed", G_CALLBACK (adj_changed), plane);
}
break;
case PROP_WIDTH_ADJUSTMENT:
adjustment = GTK_ADJUSTMENT (g_value_get_object (value));
if (adjustment)
{
plane->width_adj = g_object_ref_sink (adjustment);
g_signal_connect_swapped (adjustment, "value-changed", G_CALLBACK (adj_changed), plane);
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gtk_font_plane_class_init (GtkFontPlaneClass *class)
{
GObjectClass *object_class = G_OBJECT_CLASS (class);
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
object_class->finalize = plane_finalize;
object_class->set_property = plane_set_property;
widget_class->snapshot = plane_snapshot;
g_object_class_install_property (object_class,
PROP_WEIGHT_ADJUSTMENT,
g_param_spec_object ("weight-adjustment",
NULL,
NULL,
GTK_TYPE_ADJUSTMENT,
G_PARAM_WRITABLE |
G_PARAM_CONSTRUCT_ONLY));
g_object_class_install_property (object_class,
PROP_WIDTH_ADJUSTMENT,
g_param_spec_object ("width-adjustment",
NULL,
NULL,
GTK_TYPE_ADJUSTMENT,
G_PARAM_WRITABLE |
G_PARAM_CONSTRUCT_ONLY));
}
GtkWidget *
gtk_font_plane_new (GtkAdjustment *weight_adj,
GtkAdjustment *width_adj)
{
return g_object_new (GTK_TYPE_FONT_PLANE,
"weight-adjustment", weight_adj,
"width-adjustment", width_adj,
NULL);
}