1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /** @file
3  * Collection of shorthands to deal with GDK events.
4  */
5 /* Authors:
6  *   Krzysztof Kosiński <tweenk.pl@gmail.com>
7  *
8  * Copyright (C) 2009 Authors
9  * Released under GNU GPL v2+, read the file 'COPYING' for more information.
10  */
11 
12 #include <cstring>
13 #include <gdk/gdk.h>
14 #include <gdk/gdkkeysyms.h>
15 #include <gdkmm/display.h>
16 #include "ui/tool/event-utils.h"
17 
18 namespace Inkscape {
19 namespace UI {
20 
21 
shortcut_key(GdkEventKey const & event)22 guint shortcut_key(GdkEventKey const &event)
23 {
24     guint shortcut_key = 0;
25     gdk_keymap_translate_keyboard_state(
26             Gdk::Display::get_default()->get_keymap(),
27             event.hardware_keycode,
28             (GdkModifierType) event.state,
29             0   /*event->key.group*/,
30             &shortcut_key, nullptr, nullptr, nullptr);
31     return shortcut_key;
32 }
33 
combine_key_events(guint keyval,gint mask)34 unsigned combine_key_events(guint keyval, gint mask)
35 {
36     GdkEvent *event_next;
37     gint i = 0;
38 
39     event_next = gdk_event_get();
40     // while the next event is also a key notify with the same keyval and mask,
41     while (event_next && (event_next->type == GDK_KEY_PRESS || event_next->type == GDK_KEY_RELEASE)
42            && event_next->key.keyval == keyval
43            && (!mask || event_next->key.state & mask)) {
44         if (event_next->type == GDK_KEY_PRESS)
45             i ++;
46         // kill it
47         gdk_event_free(event_next);
48         // get next
49         event_next = gdk_event_get();
50     }
51     // otherwise, put it back onto the queue
52     if (event_next) gdk_event_put(event_next);
53 
54     return i;
55 }
56 
57 /** Returns the modifier state valid after this event. Use this when you process events
58  * that change the modifier state. Currently handles only Shift, Ctrl, Alt. */
state_after_event(GdkEvent * event)59 unsigned state_after_event(GdkEvent *event)
60 {
61     unsigned state = 0;
62     switch (event->type) {
63     case GDK_KEY_PRESS:
64         state = event->key.state;
65         switch(shortcut_key(event->key)) {
66         case GDK_KEY_Shift_L:
67         case GDK_KEY_Shift_R:
68             state |= GDK_SHIFT_MASK;
69             break;
70         case GDK_KEY_Control_L:
71         case GDK_KEY_Control_R:
72             state |= GDK_CONTROL_MASK;
73             break;
74         case GDK_KEY_Alt_L:
75         case GDK_KEY_Alt_R:
76             state |= GDK_MOD1_MASK;
77             break;
78         default: break;
79         }
80         break;
81     case GDK_KEY_RELEASE:
82         state = event->key.state;
83         switch(shortcut_key(event->key)) {
84         case GDK_KEY_Shift_L:
85         case GDK_KEY_Shift_R:
86             state &= ~GDK_SHIFT_MASK;
87             break;
88         case GDK_KEY_Control_L:
89         case GDK_KEY_Control_R:
90             state &= ~GDK_CONTROL_MASK;
91             break;
92         case GDK_KEY_Alt_L:
93         case GDK_KEY_Alt_R:
94             state &= ~GDK_MOD1_MASK;
95             break;
96         default: break;
97         }
98         break;
99     default: break;
100     }
101     return state;
102 }
103 
104 } // namespace UI
105 } // namespace Inkscape
106 
107 /*
108   Local Variables:
109   mode:c++
110   c-file-style:"stroustrup"
111   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
112   indent-tabs-mode:nil
113   fill-column:99
114   End:
115 */
116 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :
117