ctypes module for using libspnav from python

1 files changed, 80 insertions, 0 deletions

diff --git a/spnav.py b/spnav.py
new file mode 100644
index 0000000..9079114
--- /dev/null
+++ b/spnav.py
@@ -0,0 +1,80 @@
+from ctypes import cdll, c_int, c_uint, c_void_p, byref, Structure, Union
+
+libspnav = cdll.LoadLibrary('libspnav.so')
+
+SPNAV_EVENT_ANY = 0
+SPNAV_EVENT_MOTION = 1
+SPNAV_EVENT_BUTTON = 2
+
+class spnav_event_motion(Structure):
+    _fields_ = [('type', c_int),
+                ('x', c_int),
+                ('y', c_int),
+                ('z', c_int),
+                ('rx', c_int),
+                ('ry', c_int),
+                ('rz', c_int),
+                ('period', c_uint),
+                ('data', c_void_p)]
+
+class spnav_event_button(Structure):
+    _fields_ = [('type', c_int),
+                ('press', c_int),
+                ('bnum', c_int)]
+
+class spnav_event(Union):
+    _fields_ = [('type', c_int),
+                ('motion', spnav_event_motion),
+                ('button', spnav_event_button) ]
+
+    def __str__(self):
+        if self.type == SPNAV_EVENT_ANY:
+            return 'SPNAV_EVENT_ANY'
+        elif self.type == SPNAV_EVENT_MOTION:
+            m = self.motion
+            return 'SPNAV_EVENT_MOTION t(%d,%d,%d) r(%d,%d,%d)' % (m.x, m.y, m.z, m.rx, m.ry, m.rz)
+        elif self.type == SPNAV_EVENT_BUTTON:
+            if self.button.press:
+                state = 'down'
+            else:
+                state = 'up'
+            return 'SPNAV_EVENT_BUTTON %d %s' % (self.button.bnum, state)
+    
+def spnav_open():
+    if libspnav.spnav_open() == -1:
+        raise Exception('failed to connect to the space navigator daemon')
+
+def spnav_close():
+    libspnav.spnav_close()
+
+def spnav_fd():
+    return libspnav.spnav_fd()
+
+def spnav_wait_event():
+    ev = spnav_event()
+    ret = libspnav.spnav_wait_event(byref(ev))
+    if ret:
+        return ev
+    else:
+        raise Exception('non-zero return code from spnav_wait_event()')
+
+def spnav_poll_event():
+    ev = spnav_event()
+    ret = libspnav.spnav_poll_event(byref(ev))
+    if ret == 0:
+        return None
+    else:
+        return ev
+
+def spnav_remove_events(event_type):
+    return libspnav.spnav_remove_events(event_type)
+
+if __name__ == '__main__':
+    spnav_open()
+    try:
+        while True:
+            ev = spnav_wait_event()
+            print ev
+    finally:
+        spnav_close()
+