Wrap render function in SWIG threads macro, to disable Python GIL

Author: stephen322

library/rpi_ws281x.i

@@ -1,6 +1,8 @@
 // SWIG interface file to define rpi_ws281x library python wrapper.
 // Author: Tony DiCola ([email protected]), Jeremy Garff ([email protected])
 
+%nothread;
+
 // Define module name rpi_ws281x.  This will actually be imported under
 // the name _rpi_ws281x following the SWIG & Python conventions.
 %module rpi_ws281x
@@ -92,3 +94,12 @@ static int convert_iarray(PyObject *input, uint8_t *ptr, int size) {
         return &ws->channel[channelnum];
     }
 %}
+
+%thread;
+%inline %{
+    ws2811_return_t ws2811_render_nogil(ws2811_t *ws2811)
+    {
+        return ws2811_render(ws2811);
+    }
+%}
+%nothread;

library/rpi_ws281x.py

@@ -5,7 +5,6 @@
 # the SWIG interface file instead.
 
 from sys import version_info as _swig_python_version_info
-
 if _swig_python_version_info < (2, 7, 0):
     raise RuntimeError("Python 2.7 or later required")
 
@@ -20,17 +19,12 @@
 except ImportError:
     import __builtin__
 
-
 def _swig_repr(self):
     try:
         strthis = "proxy of " + self.this.__repr__()
     except __builtin__.Exception:
         strthis = ""
-    return "<%s.%s; %s >" % (
-        self.__class__.__module__,
-        self.__class__.__name__,
-        strthis,
-    )
+    return "<%s.%s; %s >" % (self.__class__.__module__, self.__class__.__name__, strthis,)
 
 
 def _swig_setattr_nondynamic_instance_variable(set):
@@ -43,7 +37,6 @@ def set_instance_attr(self, name, value):
             set(self, name, value)
         else:
             raise AttributeError("You cannot add instance attributes to %s" % self)
-
     return set_instance_attr
 
 
@@ -53,22 +46,18 @@ def set_class_attr(cls, name, value):
             set(cls, name, value)
         else:
             raise AttributeError("You cannot add class attributes to %s" % cls)
-
     return set_class_attr
 
 
 def _swig_add_metaclass(metaclass):
     """Class decorator for adding a metaclass to a SWIG wrapped class - a slimmed down version of six.add_metaclass"""
-
     def wrapper(cls):
         return metaclass(cls.__name__, cls.__bases__, cls.__dict__.copy())
-
     return wrapper
 
 
 class _SwigNonDynamicMeta(type):
     """Meta class to enforce nondynamic attributes (no new attributes) for a class"""
-
     __setattr__ = _swig_setattr_nondynamic_class_variable(type.__setattr__)
 
 
@@ -89,83 +78,42 @@ class _SwigNonDynamicMeta(type):
 WS2812_STRIP = _rpi_ws281x.WS2812_STRIP
 SK6812_STRIP = _rpi_ws281x.SK6812_STRIP
 SK6812W_STRIP = _rpi_ws281x.SK6812W_STRIP
-
-
 class ws2811_channel_t(object):
-    thisown = property(
-        lambda x: x.this.own(), lambda x, v: x.this.own(v), doc="The membership flag"
-    )
+    thisown = property(lambda x: x.this.own(), lambda x, v: x.this.own(v), doc="The membership flag")
     __repr__ = _swig_repr
-    gpionum = property(
-        _rpi_ws281x.ws2811_channel_t_gpionum_get,
-        _rpi_ws281x.ws2811_channel_t_gpionum_set,
-    )
-    invert = property(
-        _rpi_ws281x.ws2811_channel_t_invert_get, _rpi_ws281x.ws2811_channel_t_invert_set
-    )
-    count = property(
-        _rpi_ws281x.ws2811_channel_t_count_get, _rpi_ws281x.ws2811_channel_t_count_set
-    )
-    strip_type = property(
-        _rpi_ws281x.ws2811_channel_t_strip_type_get,
-        _rpi_ws281x.ws2811_channel_t_strip_type_set,
-    )
-    leds = property(
-        _rpi_ws281x.ws2811_channel_t_leds_get, _rpi_ws281x.ws2811_channel_t_leds_set
-    )
-    brightness = property(
-        _rpi_ws281x.ws2811_channel_t_brightness_get,
-        _rpi_ws281x.ws2811_channel_t_brightness_set,
-    )
-    wshift = property(
-        _rpi_ws281x.ws2811_channel_t_wshift_get, _rpi_ws281x.ws2811_channel_t_wshift_set
-    )
-    rshift = property(
-        _rpi_ws281x.ws2811_channel_t_rshift_get, _rpi_ws281x.ws2811_channel_t_rshift_set
-    )
-    gshift = property(
-        _rpi_ws281x.ws2811_channel_t_gshift_get, _rpi_ws281x.ws2811_channel_t_gshift_set
-    )
-    bshift = property(
-        _rpi_ws281x.ws2811_channel_t_bshift_get, _rpi_ws281x.ws2811_channel_t_bshift_set
-    )
-    gamma = property(
-        _rpi_ws281x.ws2811_channel_t_gamma_get, _rpi_ws281x.ws2811_channel_t_gamma_set
-    )
+    gpionum = property(_rpi_ws281x.ws2811_channel_t_gpionum_get, _rpi_ws281x.ws2811_channel_t_gpionum_set)
+    invert = property(_rpi_ws281x.ws2811_channel_t_invert_get, _rpi_ws281x.ws2811_channel_t_invert_set)
+    count = property(_rpi_ws281x.ws2811_channel_t_count_get, _rpi_ws281x.ws2811_channel_t_count_set)
+    strip_type = property(_rpi_ws281x.ws2811_channel_t_strip_type_get, _rpi_ws281x.ws2811_channel_t_strip_type_set)
+    leds = property(_rpi_ws281x.ws2811_channel_t_leds_get, _rpi_ws281x.ws2811_channel_t_leds_set)
+    brightness = property(_rpi_ws281x.ws2811_channel_t_brightness_get, _rpi_ws281x.ws2811_channel_t_brightness_set)
+    wshift = property(_rpi_ws281x.ws2811_channel_t_wshift_get, _rpi_ws281x.ws2811_channel_t_wshift_set)
+    rshift = property(_rpi_ws281x.ws2811_channel_t_rshift_get, _rpi_ws281x.ws2811_channel_t_rshift_set)
+    gshift = property(_rpi_ws281x.ws2811_channel_t_gshift_get, _rpi_ws281x.ws2811_channel_t_gshift_set)
+    bshift = property(_rpi_ws281x.ws2811_channel_t_bshift_get, _rpi_ws281x.ws2811_channel_t_bshift_set)
+    gamma = property(_rpi_ws281x.ws2811_channel_t_gamma_get, _rpi_ws281x.ws2811_channel_t_gamma_set)
 
     def __init__(self):
         _rpi_ws281x.ws2811_channel_t_swiginit(self, _rpi_ws281x.new_ws2811_channel_t())
-
     __swig_destroy__ = _rpi_ws281x.delete_ws2811_channel_t
 
-
 # Register ws2811_channel_t in _rpi_ws281x:
 _rpi_ws281x.ws2811_channel_t_swigregister(ws2811_channel_t)
 
-
 class ws2811_t(object):
-    thisown = property(
-        lambda x: x.this.own(), lambda x, v: x.this.own(v), doc="The membership flag"
-    )
+    thisown = property(lambda x: x.this.own(), lambda x, v: x.this.own(v), doc="The membership flag")
     __repr__ = _swig_repr
-    render_wait_time = property(
-        _rpi_ws281x.ws2811_t_render_wait_time_get,
-        _rpi_ws281x.ws2811_t_render_wait_time_set,
-    )
+    render_wait_time = property(_rpi_ws281x.ws2811_t_render_wait_time_get, _rpi_ws281x.ws2811_t_render_wait_time_set)
     device = property(_rpi_ws281x.ws2811_t_device_get, _rpi_ws281x.ws2811_t_device_set)
     rpi_hw = property(_rpi_ws281x.ws2811_t_rpi_hw_get, _rpi_ws281x.ws2811_t_rpi_hw_set)
     freq = property(_rpi_ws281x.ws2811_t_freq_get, _rpi_ws281x.ws2811_t_freq_set)
     dmanum = property(_rpi_ws281x.ws2811_t_dmanum_get, _rpi_ws281x.ws2811_t_dmanum_set)
-    channel = property(
-        _rpi_ws281x.ws2811_t_channel_get, _rpi_ws281x.ws2811_t_channel_set
-    )
+    channel = property(_rpi_ws281x.ws2811_t_channel_get, _rpi_ws281x.ws2811_t_channel_set)
 
     def __init__(self):
         _rpi_ws281x.ws2811_t_swiginit(self, _rpi_ws281x.new_ws2811_t())
-
     __swig_destroy__ = _rpi_ws281x.delete_ws2811_t
 
-
 # Register ws2811_t in _rpi_ws281x:
 _rpi_ws281x.ws2811_t_swigregister(ws2811_t)
 
@@ -186,38 +134,34 @@ def __init__(self):
 WS2811_ERROR_SPI_TRANSFER = _rpi_ws281x.WS2811_ERROR_SPI_TRANSFER
 WS2811_RETURN_STATE_COUNT = _rpi_ws281x.WS2811_RETURN_STATE_COUNT
 
-
 def ws2811_init(ws2811):
     return _rpi_ws281x.ws2811_init(ws2811)
 
-
 def ws2811_fini(ws2811):
     return _rpi_ws281x.ws2811_fini(ws2811)
 
-
 def ws2811_render(ws2811):
     return _rpi_ws281x.ws2811_render(ws2811)
 
-
 def ws2811_wait(ws2811):
     return _rpi_ws281x.ws2811_wait(ws2811)
 
-
 def ws2811_get_return_t_str(state):
     return _rpi_ws281x.ws2811_get_return_t_str(state)
 
-
 def ws2811_set_custom_gamma_factor(ws2811, gamma_factor):
     return _rpi_ws281x.ws2811_set_custom_gamma_factor(ws2811, gamma_factor)
 
-
 def ws2811_led_get(channel, lednum):
     return _rpi_ws281x.ws2811_led_get(channel, lednum)
 
-
 def ws2811_led_set(channel, lednum, color):
     return _rpi_ws281x.ws2811_led_set(channel, lednum, color)
 
-
 def ws2811_channel_get(ws, channelnum):
     return _rpi_ws281x.ws2811_channel_get(ws, channelnum)
+
+def ws2811_render_nogil(ws2811):
+    return _rpi_ws281x.ws2811_render_nogil(ws2811)
+
+

library/rpi_ws281x/rpi_ws281x.py

@@ -149,6 +149,13 @@ def show(self):
             str_resp = ws.ws2811_get_return_t_str(resp)
             raise RuntimeError('ws2811_render failed with code {0} ({1})'.format(resp, str_resp))
 
+    def show_nogil(self):
+        """Update the display with the data from the LED buffer, with no Global-Interpreter-Lock."""
+        resp = ws.ws2811_render_nogil(self._leds)
+        if resp != 0:
+            str_resp = ws.ws2811_get_return_t_str(resp)
+            raise RuntimeError('ws2811_render failed with code {0} ({1})'.format(resp, str_resp))
+
     def setPixelColor(self, n, color):
         """Set LED at position n to the provided 24-bit color value (in RGB order).
         """

library/rpi_ws281x_wrap.c

@@ -13,6 +13,7 @@
 #define SWIGPYTHON
 #endif
 
+#define SWIG_PYTHON_THREADS
 #define SWIG_PYTHON_DIRECTOR_NO_VTABLE
 
 /* -----------------------------------------------------------------------------
@@ -3132,6 +3133,12 @@ SWIG_FromCharPtr(const char *cptr)
         return &ws->channel[channelnum];
     }
 
+
+    ws2811_return_t ws2811_render_nogil(ws2811_t *ws2811)
+    {
+        return ws2811_render(ws2811);
+    }
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -4370,6 +4377,33 @@ SWIGINTERN PyObject *_wrap_ws2811_channel_get(PyObject *SWIGUNUSEDPARM(self), Py
 }
 
 
+SWIGINTERN PyObject *_wrap_ws2811_render_nogil(PyObject *SWIGUNUSEDPARM(self), PyObject *args) {
+  PyObject *resultobj = 0;
+  ws2811_t *arg1 = (ws2811_t *) 0 ;
+  void *argp1 = 0 ;
+  int res1 = 0 ;
+  PyObject *swig_obj[1] ;
+  ws2811_return_t result;
+  
+  if (!args) SWIG_fail;
+  swig_obj[0] = args;
+  res1 = SWIG_ConvertPtr(swig_obj[0], &argp1,SWIGTYPE_p_ws2811_t, 0 |  0 );
+  if (!SWIG_IsOK(res1)) {
+    SWIG_exception_fail(SWIG_ArgError(res1), "in method '" "ws2811_render_nogil" "', argument " "1"" of type '" "ws2811_t *""'"); 
+  }
+  arg1 = (ws2811_t *)(argp1);
+  {
+    SWIG_PYTHON_THREAD_BEGIN_ALLOW;
+    result = (ws2811_return_t)ws2811_render_nogil(arg1);
+    SWIG_PYTHON_THREAD_END_ALLOW;
+  }
+  resultobj = SWIG_From_int((int)(result));
+  return resultobj;
+fail:
+  return NULL;
+}
+
+
 static PyMethodDef SwigMethods[] = {
 	 { "SWIG_PyInstanceMethod_New", SWIG_PyInstanceMethod_New, METH_O, NULL},
 	 { "ws2811_channel_t_gpionum_set", _wrap_ws2811_channel_t_gpionum_set, METH_VARARGS, NULL},
@@ -4423,6 +4457,7 @@ static PyMethodDef SwigMethods[] = {
 	 { "ws2811_led_get", _wrap_ws2811_led_get, METH_VARARGS, NULL},
 	 { "ws2811_led_set", _wrap_ws2811_led_set, METH_VARARGS, NULL},
 	 { "ws2811_channel_get", _wrap_ws2811_channel_get, METH_VARARGS, NULL},
+	 { "ws2811_render_nogil", _wrap_ws2811_render_nogil, METH_O, NULL},
 	 { NULL, NULL, 0, NULL }
 };
 
@@ -5263,6 +5298,9 @@ SWIG_init(void) {
   SWIG_Python_SetConstant(d, "WS2811_ERROR_SPI_SETUP",SWIG_From_int((int)(WS2811_ERROR_SPI_SETUP)));
   SWIG_Python_SetConstant(d, "WS2811_ERROR_SPI_TRANSFER",SWIG_From_int((int)(WS2811_ERROR_SPI_TRANSFER)));
   SWIG_Python_SetConstant(d, "WS2811_RETURN_STATE_COUNT",SWIG_From_int((int)(WS2811_RETURN_STATE_COUNT)));
+  
+  /* Initialize threading */
+  SWIG_PYTHON_INITIALIZE_THREADS;
 #if PY_VERSION_HEX >= 0x03000000
   return m;
 #else