gtk3/demos/gtk-demo/event_axes.c
Carlos Garnacho ae29157a63 demos: Add pad support to "event axes" demo
And rename it to "Touch and Drawing Tablets", since it's no longer about
"axes" really.

As for pad support in the demo, just keep it "simple", make the
controller handle all pad devices, and make all the actions have the
same callback.

https://bugzilla.gnome.org/show_bug.cgi?id=770026
2016-08-23 21:01:45 +02:00

638 lines
17 KiB
C

/* Touch and Drawing Tablets
*
* Demonstrates advanced handling of event information from exotic
* input devices.
*
* On one hand, this snippet demonstrates management of drawing tablets,
* those contain additional information for the pointer other than
* X/Y coordinates. Tablet pads events are mapped to actions, which
* are both defined and interpreted by the application.
*
* Input axes are dependent on hardware devices, on linux/unix you
* can see the device axes through xinput list <device>. Each time
* a different hardware device is used to move the pointer, the
* master device will be updated to match the axes it provides,
* these changes can be tracked through GdkDevice::changed, or
* checking gdk_event_get_source_device().
*
* On the other hand, this demo handles basic multitouch events,
* each event coming from an specific touchpoint will contain a
* GdkEventSequence that's unique for its lifetime, so multiple
* touchpoints can be tracked.
*/
#include <glib/gi18n.h>
#include <gtk/gtk.h>
typedef struct {
GdkDevice *last_source;
GdkDeviceTool *last_tool;
gdouble *axes;
GdkRGBA color;
gdouble x;
gdouble y;
} AxesInfo;
typedef struct {
GHashTable *pointer_info; /* GdkDevice -> AxesInfo */
GHashTable *touch_info; /* GdkEventSequence -> AxesInfo */
} EventData;
const gchar *colors[] = {
"black",
"orchid",
"fuchsia",
"indigo",
"thistle",
"sienna",
"azure",
"plum",
"lime",
"navy",
"maroon",
"burlywood"
};
static GtkPadActionEntry pad_actions[] = {
{ GTK_PAD_ACTION_BUTTON, 1, -1, N_("Nuclear strike"), "pad.nuke" },
{ GTK_PAD_ACTION_BUTTON, 2, -1, N_("Release siberian methane reserves"), "pad.heat" },
{ GTK_PAD_ACTION_BUTTON, 3, -1, N_("Release solar flare"), "pad.fry" },
{ GTK_PAD_ACTION_BUTTON, 4, -1, N_("De-stabilize Oort cloud"), "pad.fall" },
{ GTK_PAD_ACTION_BUTTON, 5, -1, N_("Ignite WR-104"), "pad.burst" },
{ GTK_PAD_ACTION_BUTTON, 6, -1, N_("Lart whoever asks about this button"), "pad.lart" },
{ GTK_PAD_ACTION_RING, -1, -1, N_("Earth axial tilt"), "pad.tilt" },
{ GTK_PAD_ACTION_STRIP, -1, -1, N_("Extent of weak nuclear force"), "pad.dissolve" },
};
static const gchar *pad_action_results[] = {
"",
"",
"",
"",
"",
"💫",
"",
""
};
static guint cur_color = 0;
static guint pad_action_timeout_id = 0;
static AxesInfo *
axes_info_new (void)
{
AxesInfo *info;
info = g_new0 (AxesInfo, 1);
gdk_rgba_parse (&info->color, colors[cur_color]);
cur_color = (cur_color + 1) % G_N_ELEMENTS (colors);
return info;
}
static EventData *
event_data_new (void)
{
EventData *data;
data = g_new0 (EventData, 1);
data->pointer_info = g_hash_table_new_full (NULL, NULL, NULL,
(GDestroyNotify) g_free);
data->touch_info = g_hash_table_new_full (NULL, NULL, NULL,
(GDestroyNotify) g_free);
return data;
}
static void
event_data_free (EventData *data)
{
g_hash_table_destroy (data->pointer_info);
g_hash_table_destroy (data->touch_info);
g_free (data);
}
static void
update_axes_from_event (GdkEvent *event,
EventData *data)
{
GdkDevice *device, *source_device;
GdkEventSequence *sequence;
GdkDeviceTool *tool;
gdouble x, y;
AxesInfo *info;
device = gdk_event_get_device (event);
source_device = gdk_event_get_source_device (event);
sequence = gdk_event_get_event_sequence (event);
tool = gdk_event_get_device_tool (event);
if (event->type == GDK_TOUCH_END ||
event->type == GDK_TOUCH_CANCEL)
{
g_hash_table_remove (data->touch_info, sequence);
return;
}
else if (event->type == GDK_LEAVE_NOTIFY)
{
g_hash_table_remove (data->pointer_info, device);
return;
}
if (!sequence)
{
info = g_hash_table_lookup (data->pointer_info, device);
if (!info)
{
info = axes_info_new ();
g_hash_table_insert (data->pointer_info, device, info);
}
}
else
{
info = g_hash_table_lookup (data->touch_info, sequence);
if (!info)
{
info = axes_info_new ();
g_hash_table_insert (data->touch_info, sequence, info);
}
}
if (info->last_source != source_device)
info->last_source = source_device;
if (info->last_tool != tool)
info->last_tool = tool;
g_clear_pointer (&info->axes, g_free);
if (event->type == GDK_TOUCH_BEGIN ||
event->type == GDK_TOUCH_UPDATE)
{
if (sequence && event->touch.emulating_pointer)
g_hash_table_remove (data->pointer_info, device);
}
if (event->type == GDK_MOTION_NOTIFY)
{
info->axes =
g_memdup (event->motion.axes,
sizeof (gdouble) * gdk_device_get_n_axes (source_device));
}
else if (event->type == GDK_BUTTON_PRESS ||
event->type == GDK_BUTTON_RELEASE)
{
info->axes =
g_memdup (event->button.axes,
sizeof (gdouble) * gdk_device_get_n_axes (source_device));
}
if (gdk_event_get_coords (event, &x, &y))
{
info->x = x;
info->y = y;
}
}
static gboolean
event_cb (GtkWidget *widget,
GdkEvent *event,
gpointer user_data)
{
update_axes_from_event (event, user_data);
gtk_widget_queue_draw (widget);
return FALSE;
}
static void
render_arrow (cairo_t *cr,
gdouble x_diff,
gdouble y_diff,
const gchar *label)
{
cairo_save (cr);
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_new_path (cr);
cairo_move_to (cr, 0, 0);
cairo_line_to (cr, x_diff, y_diff);
cairo_stroke (cr);
cairo_move_to (cr, x_diff, y_diff);
cairo_show_text (cr, label);
cairo_restore (cr);
}
static void
draw_axes_info (cairo_t *cr,
AxesInfo *info,
GtkAllocation *allocation)
{
gdouble pressure, tilt_x, tilt_y, distance, wheel, rotation, slider;
GdkAxisFlags axes = gdk_device_get_axes (info->last_source);
cairo_save (cr);
cairo_set_line_width (cr, 1);
gdk_cairo_set_source_rgba (cr, &info->color);
cairo_move_to (cr, 0, info->y);
cairo_line_to (cr, allocation->width, info->y);
cairo_move_to (cr, info->x, 0);
cairo_line_to (cr, info->x, allocation->height);
cairo_stroke (cr);
cairo_translate (cr, info->x, info->y);
if (!info->axes)
{
cairo_restore (cr);
return;
}
if (axes & GDK_AXIS_FLAG_PRESSURE)
{
cairo_pattern_t *pattern;
gdk_device_get_axis (info->last_source, info->axes, GDK_AXIS_PRESSURE,
&pressure);
pattern = cairo_pattern_create_radial (0, 0, 0, 0, 0, 100);
cairo_pattern_add_color_stop_rgba (pattern, pressure, 1, 0, 0, pressure);
cairo_pattern_add_color_stop_rgba (pattern, 1, 0, 0, 1, 0);
cairo_set_source (cr, pattern);
cairo_arc (cr, 0, 0, 100, 0, 2 * G_PI);
cairo_fill (cr);
cairo_pattern_destroy (pattern);
}
if (axes & GDK_AXIS_FLAG_XTILT &&
axes & GDK_AXIS_FLAG_YTILT)
{
gdk_device_get_axis (info->last_source, info->axes, GDK_AXIS_XTILT,
&tilt_x);
gdk_device_get_axis (info->last_source, info->axes, GDK_AXIS_YTILT,
&tilt_y);
render_arrow (cr, tilt_x * 100, tilt_y * 100, "Tilt");
}
if (axes & GDK_AXIS_FLAG_DISTANCE)
{
double dashes[] = { 5.0, 5.0 };
cairo_text_extents_t extents;
gdk_device_get_axis (info->last_source, info->axes, GDK_AXIS_DISTANCE,
&distance);
cairo_save (cr);
cairo_move_to (cr, distance * 100, 0);
cairo_set_source_rgb (cr, 0.0, 0.0, 0.0);
cairo_set_dash (cr, dashes, 2, 0.0);
cairo_arc (cr, 0, 0, distance * 100, 0, 2 * G_PI);
cairo_stroke (cr);
cairo_move_to (cr, 0, -distance * 100);
cairo_text_extents (cr, "Distance", &extents);
cairo_rel_move_to (cr, -extents.width / 2, 0);
cairo_show_text (cr, "Distance");
cairo_move_to (cr, 0, 0);
cairo_restore (cr);
}
if (axes & GDK_AXIS_FLAG_WHEEL)
{
gdk_device_get_axis (info->last_source, info->axes, GDK_AXIS_WHEEL,
&wheel);
cairo_save (cr);
cairo_set_line_width (cr, 10);
cairo_set_source_rgba (cr, 0, 0, 0, 0.5);
cairo_new_sub_path (cr);
cairo_arc (cr, 0, 0, 100, 0, wheel * 2 * G_PI);
cairo_stroke (cr);
cairo_restore (cr);
}
if (axes & GDK_AXIS_FLAG_ROTATION)
{
gdk_device_get_axis (info->last_source, info->axes, GDK_AXIS_ROTATION,
&rotation);
rotation *= 2 * G_PI;
cairo_save (cr);
cairo_rotate (cr, - G_PI / 2);
cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
cairo_set_line_width (cr, 5);
cairo_new_sub_path (cr);
cairo_arc (cr, 0, 0, 100, 0, rotation);
cairo_stroke (cr);
cairo_restore (cr);
}
if (axes & GDK_AXIS_FLAG_SLIDER)
{
cairo_pattern_t *pattern, *mask;
gdk_device_get_axis (info->last_source, info->axes, GDK_AXIS_SLIDER,
&slider);
cairo_save (cr);
cairo_move_to (cr, 0, -10);
cairo_rel_line_to (cr, 0, -50);
cairo_rel_line_to (cr, 10, 0);
cairo_rel_line_to (cr, -5, 50);
cairo_close_path (cr);
cairo_clip_preserve (cr);
pattern = cairo_pattern_create_linear (0, -10, 0, -60);
cairo_pattern_add_color_stop_rgb (pattern, 0, 0, 1, 0);
cairo_pattern_add_color_stop_rgb (pattern, 1, 1, 0, 0);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
mask = cairo_pattern_create_linear (0, -10, 0, -60);
cairo_pattern_add_color_stop_rgba (mask, 0, 0, 0, 0, 1);
cairo_pattern_add_color_stop_rgba (mask, slider, 0, 0, 0, 1);
cairo_pattern_add_color_stop_rgba (mask, slider, 0, 0, 0, 0);
cairo_pattern_add_color_stop_rgba (mask, 1, 0, 0, 0, 0);
cairo_mask (cr, mask);
cairo_pattern_destroy (mask);
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_stroke (cr);
cairo_restore (cr);
}
cairo_restore (cr);
}
static const gchar *
tool_type_to_string (GdkDeviceToolType tool_type)
{
switch (tool_type)
{
case GDK_DEVICE_TOOL_TYPE_PEN:
return "Pen";
case GDK_DEVICE_TOOL_TYPE_ERASER:
return "Eraser";
case GDK_DEVICE_TOOL_TYPE_BRUSH:
return "Brush";
case GDK_DEVICE_TOOL_TYPE_PENCIL:
return "Pencil";
case GDK_DEVICE_TOOL_TYPE_AIRBRUSH:
return "Airbrush";
case GDK_DEVICE_TOOL_TYPE_MOUSE:
return "Mouse";
case GDK_DEVICE_TOOL_TYPE_LENS:
return "Lens cursor";
case GDK_DEVICE_TOOL_TYPE_UNKNOWN:
default:
return "Unknown";
}
}
static void
draw_device_info (GtkWidget *widget,
cairo_t *cr,
GdkEventSequence *sequence,
gint *y,
AxesInfo *info)
{
PangoLayout *layout;
GString *string;
gint height;
cairo_save (cr);
string = g_string_new (NULL);
g_string_append_printf (string, "Source: %s",
gdk_device_get_name (info->last_source));
if (sequence)
g_string_append_printf (string, "\nSequence: %d",
GPOINTER_TO_UINT (sequence));
if (info->last_tool)
{
const gchar *tool_type;
guint64 serial;
tool_type = tool_type_to_string (gdk_device_tool_get_tool_type (info->last_tool));
serial = gdk_device_tool_get_serial (info->last_tool);
g_string_append_printf (string, "\nTool: %s", tool_type);
if (serial != 0)
g_string_append_printf (string, ", Serial: %lx", serial);
}
cairo_move_to (cr, 10, *y);
layout = gtk_widget_create_pango_layout (widget, string->str);
pango_cairo_show_layout (cr, layout);
cairo_stroke (cr);
pango_layout_get_pixel_size (layout, NULL, &height);
gdk_cairo_set_source_rgba (cr, &info->color);
cairo_set_line_width (cr, 10);
cairo_move_to (cr, 0, *y);
*y = *y + height;
cairo_line_to (cr, 0, *y);
cairo_stroke (cr);
cairo_restore (cr);
g_object_unref (layout);
g_string_free (string, TRUE);
}
static gboolean
draw_cb (GtkWidget *widget,
cairo_t *cr,
gpointer user_data)
{
EventData *data = user_data;
GtkAllocation allocation;
AxesInfo *info;
GHashTableIter iter;
gpointer key, value;
gint y = 0;
gtk_widget_get_allocation (widget, &allocation);
/* Draw Abs info */
g_hash_table_iter_init (&iter, data->pointer_info);
while (g_hash_table_iter_next (&iter, NULL, &value))
{
info = value;
draw_axes_info (cr, info, &allocation);
}
g_hash_table_iter_init (&iter, data->touch_info);
while (g_hash_table_iter_next (&iter, NULL, &value))
{
info = value;
draw_axes_info (cr, info, &allocation);
}
/* Draw name, color legend and misc data */
g_hash_table_iter_init (&iter, data->pointer_info);
while (g_hash_table_iter_next (&iter, NULL, &value))
{
info = value;
draw_device_info (widget, cr, NULL, &y, info);
}
g_hash_table_iter_init (&iter, data->touch_info);
while (g_hash_table_iter_next (&iter, &key, &value))
{
info = value;
draw_device_info (widget, cr, key, &y, info);
}
return FALSE;
}
static void
update_label_text (GtkWidget *label,
const gchar *text)
{
gchar *markup = NULL;
if (text)
markup = g_strdup_printf ("<span font='48.0'>%s</span>", text);
gtk_label_set_markup (GTK_LABEL (label), markup);
g_free (markup);
}
static gboolean
reset_label_text_timeout_cb (gpointer user_data)
{
GtkWidget *label = user_data;
update_label_text (label, NULL);
pad_action_timeout_id = 0;
return G_SOURCE_REMOVE;
}
static void
on_action_activate (GSimpleAction *action,
GVariant *parameter,
gpointer user_data)
{
GtkWidget *label = user_data;
const gchar *result;
if (pad_action_timeout_id)
g_source_remove (pad_action_timeout_id);
result = g_object_get_data (G_OBJECT (action), "action-result");
update_label_text (label, result);
pad_action_timeout_id = g_timeout_add (200, reset_label_text_timeout_cb, label);
}
static void
init_pad_controller (GtkWidget *window,
GtkWidget *label)
{
GtkPadController *pad_controller;
GSimpleActionGroup *action_group;
GSimpleAction *action;
gint i;
action_group = g_simple_action_group_new ();
pad_controller = gtk_pad_controller_new (GTK_WINDOW (window),
G_ACTION_GROUP (action_group),
NULL);
for (i = 0; i < G_N_ELEMENTS (pad_actions); i++)
{
action = g_simple_action_new (pad_actions[i].action_name, NULL);
g_signal_connect (action, "activate",
G_CALLBACK (on_action_activate), label);
g_object_set_data (G_OBJECT (action), "action-result",
(gpointer) pad_action_results[i]);
g_action_map_add_action (G_ACTION_MAP (action_group), G_ACTION (action));
g_object_unref (action);
}
gtk_pad_controller_set_action_entries (pad_controller, pad_actions,
G_N_ELEMENTS (pad_actions));
g_object_set_data_full (G_OBJECT (window), "pad-controller",
pad_controller, g_object_unref);
g_object_unref (action_group);
}
GtkWidget *
do_event_axes (GtkWidget *toplevel)
{
static GtkWidget *window = NULL;
EventData *event_data;
GtkWidget *box, *label;
if (!window)
{
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "Event Axes");
gtk_window_set_default_size (GTK_WINDOW (window), 400, 400);
g_signal_connect (window, "destroy",
G_CALLBACK (gtk_widget_destroyed), &window);
box = gtk_event_box_new ();
gtk_container_add (GTK_CONTAINER (window), box);
gtk_widget_set_support_multidevice (box, TRUE);
gtk_widget_add_events (box,
GDK_POINTER_MOTION_MASK |
GDK_BUTTON_PRESS_MASK |
GDK_BUTTON_RELEASE_MASK |
GDK_SMOOTH_SCROLL_MASK |
GDK_ENTER_NOTIFY_MASK |
GDK_LEAVE_NOTIFY_MASK |
GDK_TOUCH_MASK);
event_data = event_data_new ();
g_object_set_data_full (G_OBJECT (box), "gtk-demo-event-data",
event_data, (GDestroyNotify) event_data_free);
g_signal_connect (box, "event",
G_CALLBACK (event_cb), event_data);
g_signal_connect (box, "draw",
G_CALLBACK (draw_cb), event_data);
label = gtk_label_new ("");
gtk_label_set_use_markup (GTK_LABEL (label), TRUE);
gtk_container_add (GTK_CONTAINER (box), label);
init_pad_controller (window, label);
}
if (!gtk_widget_get_visible (window))
gtk_widget_show_all (window);
else
gtk_widget_destroy (window);
return window;
}