gtk-demo: Use GdkAxisUse instead of axis labels

Axis labels are very X specific, and are not really possible to port to other
backends such as Wayland. As such, it makes more sense to use GdkAxisUse and
GdkAxisUseFlag in order to determine the axis capabilities of a device and draw
their axes.

Signed-off-by: Stephen Chandler Paul <thatslyude@gmail.com>

1 files changed, 45 insertions, 61 deletions

diff --git a/demos/gtk-demo/event_axes.c b/demos/gtk-demo/event_axes.c
index bfec8b7faf..a12168a70b 100644
--- a/demos/gtk-demo/event_axes.c
+++ b/demos/gtk-demo/event_axes.c
@@ -24,7 +24,7 @@
 
 typedef struct {
   GdkDevice *last_source;
-  GHashTable *axes; /* axis label atom -> value */
+  gdouble *axes;
   GdkRGBA color;
   gdouble x;
   gdouble y;
@@ -59,8 +59,6 @@ axes_info_new (void)
 
   info = g_new0 (AxesInfo, 1);
   gdk_rgba_parse (&info->color, colors[cur_color]);
-  info->axes = g_hash_table_new_full (NULL, NULL, NULL,
-                                      (GDestroyNotify) g_free);
 
   cur_color = (cur_color + 1) % G_N_ELEMENTS (colors);
 
@@ -70,32 +68,9 @@ axes_info_new (void)
 static void
 axes_info_free (AxesInfo *info)
 {
-  g_hash_table_destroy (info->axes);
   g_free (info);
 }
 
-static gboolean
-axes_info_lookup (AxesInfo    *info,
-                  const gchar *axis_label,
-                  gdouble     *value)
-{
-  gdouble *val;
-  GdkAtom atom;
-
-  atom = gdk_atom_intern (axis_label, FALSE);
-
-  if (atom == GDK_NONE)
-    return FALSE;
-
-  val = g_hash_table_lookup (info->axes, GDK_ATOM_TO_POINTER (atom));
-
-  if (!val)
-    return FALSE;
-
-  *value = *val;
-  return TRUE;
-}
-
 static EventData *
 event_data_new (void)
 {
@@ -121,13 +96,11 @@ static void
 update_axes_from_event (GdkEvent  *event,
                         EventData *data)
 {
-  GdkDevice *device, *source_device;
+  GdkDevice *source_device;
   GdkEventSequence *sequence;
-  gdouble x, y, value;
-  GList *l, *axes;
+  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);
 
@@ -163,41 +136,32 @@ update_axes_from_event (GdkEvent  *event,
     }
 
   if (info->last_source != source_device)
-    {
-      g_hash_table_remove_all (info->axes);
-      info->last_source = source_device;
-    }
+    info->last_source = source_device;
+
+  g_clear_pointer (&info->axes, g_free);
 
   if (event->type == GDK_TOUCH_BEGIN ||
-      event->type == GDK_TOUCH_UPDATE ||
-      event->type == GDK_MOTION_NOTIFY ||
-      event->type == GDK_BUTTON_PRESS ||
-      event->type == GDK_BUTTON_RELEASE)
+      event->type == GDK_TOUCH_UPDATE)
     {
-      axes = gdk_device_list_axes (device);
-
       if (sequence && event->touch.emulating_pointer)
         {
           if (data->pointer_info)
             axes_info_free (data->pointer_info);
           data->pointer_info = NULL;
         }
-
-      for (l = axes; l; l = l->next)
-        {
-          gdouble *ptr;
-
-          /* All those event types are compatible wrt axes position in the struct */
-          if (!gdk_device_get_axis_value (device, event->motion.axes,
-                                          l->data, &value))
-            continue;
-
-          ptr = g_new0 (gdouble, 1);
-          *ptr = value;
-          g_hash_table_insert (info->axes, GDK_ATOM_TO_POINTER (l->data), ptr);
-        }
-
-      g_list_free (axes);
+    }
+  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))
@@ -243,6 +207,7 @@ draw_axes_info (cairo_t       *cr,
                 GtkAllocation *allocation)
 {
   gdouble pressure, tilt_x, tilt_y, wheel;
+  GdkAxisFlags axes = gdk_device_get_axes (info->last_source);
 
   cairo_save (cr);
 
@@ -257,10 +222,19 @@ draw_axes_info (cairo_t       *cr,
 
   cairo_translate (cr, info->x, info->y);
 
-  if (axes_info_lookup (info, "Abs Pressure", &pressure))
+  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);
@@ -273,12 +247,22 @@ draw_axes_info (cairo_t       *cr,
       cairo_pattern_destroy (pattern);
     }
 
-  if (axes_info_lookup (info, "Abs Tilt X", &tilt_x) &&
-      axes_info_lookup (info, "Abs Tilt Y", &tilt_y))
-    render_arrow (cr, tilt_x * 100, tilt_y * 100, "Tilt");
+  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_info_lookup (info, "Abs Wheel", &wheel))
+  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);