From 333ca35ceca739388be36cf48514fcb68f3b7aef Mon Sep 17 00:00:00 2001
From: Emmanuele Bassi <ebassi@linux.intel.com>
Date: Tue, 18 Jan 2011 16:55:14 +0000
Subject: [PATCH] device: Add get_axis_value()

We need a convenience function for extracting the value of a specific
axis type out of the array of axis values attached to events.
---
 clutter/clutter-input-device.c | 47 ++++++++++++++++++++++++++++++++++
 clutter/clutter-input-device.h |  4 +++
 2 files changed, 51 insertions(+)

diff --git a/clutter/clutter-input-device.c b/clutter/clutter-input-device.c
index 824895642..d9e0714c1 100644
--- a/clutter/clutter-input-device.c
+++ b/clutter/clutter-input-device.c
@@ -924,6 +924,9 @@ clutter_input_device_get_axis (ClutterInputDevice *device,
 {
   ClutterAxisInfo *info;
 
+  g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device),
+                        CLUTTER_INPUT_AXIS_IGNORE);
+
   if (device->axes == NULL)
     return CLUTTER_INPUT_AXIS_IGNORE;
 
@@ -935,6 +938,50 @@ clutter_input_device_get_axis (ClutterInputDevice *device,
   return info->axis;
 }
 
+/**
+ * clutter_input_device_get_axis_value:
+ * @device: a #ClutterInputDevice
+ * @axes: (array): an array of axes values, typically
+ *   coming from clutter_event_get_axes()
+ * @axis: the axis to extract
+ * @value: (out): return location for the axis value
+ *
+ * Extracts the value of the given @axis of a #ClutterInputDevice from
+ * an array of axis values.
+ *
+ * Return value: %TRUE if the value was set, and %FALSE otherwise
+ *
+ * Since: 1.6
+ */
+gboolean
+clutter_input_device_get_axis_value (ClutterInputDevice *device,
+                                     gdouble            *axes,
+                                     ClutterInputAxis    axis,
+                                     gdouble            *value)
+{
+  gint i;
+
+  g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
+  g_return_val_if_fail (device->axes != NULL, FALSE);
+
+  for (i = 0; i < device->axes->len; i++)
+    {
+      ClutterAxisInfo *info;
+
+      info = &g_array_index (device->axes, ClutterAxisInfo, i);
+
+      if (info->axis == axis)
+        {
+          if (value)
+            *value = axes[i];
+
+          return TRUE;
+        }
+    }
+
+  return FALSE;
+}
+
 /**
  * clutter_input_device_get_n_axes:
  * @device: a #ClutterInputDevice
diff --git a/clutter/clutter-input-device.h b/clutter/clutter-input-device.h
index fb305263b..7e1fbb6d8 100644
--- a/clutter/clutter-input-device.h
+++ b/clutter/clutter-input-device.h
@@ -140,6 +140,10 @@ G_CONST_RETURN gchar *  clutter_input_device_get_device_name    (ClutterInputDev
 guint                   clutter_input_device_get_n_axes         (ClutterInputDevice  *device);
 ClutterInputAxis        clutter_input_device_get_axis           (ClutterInputDevice  *device,
                                                                  guint                index_);
+gboolean                clutter_input_device_get_axis_value     (ClutterInputDevice  *device,
+                                                                 gdouble             *axes,
+                                                                 ClutterInputAxis     axis,
+                                                                 gdouble             *value);
 
 guint                   clutter_input_device_get_n_keys         (ClutterInputDevice  *device);
 void                    clutter_input_device_set_key            (ClutterInputDevice  *device,