Redraw as fast as possible (using X11 properties)

3 files changed, 46 insertions, 21 deletions

diff --git a/config.py b/config.py
index baedd62..e4f0a2e 100644
--- a/config.py
+++ b/config.py
@@ -25,9 +25,6 @@ from sugar.activity import activity
 MEASURE_ROOT = activity.get_bundle_path()
 ICONS_DIR = MEASURE_ROOT + '/icons'
 
-#In milliseconds, the delay interval after which the waveform draw function will be queued"
-REFRESH_TIME = 30
-
 #Multiplied with width and height to set placement of text
 TEXT_X_M = 0.65
 TEXT_Y_M = 0.70
diff --git a/drawwaveform.py b/drawwaveform.py
index a3c13df..6d0a784 100644
--- a/drawwaveform.py
+++ b/drawwaveform.py
@@ -53,7 +53,8 @@ class DrawWaveform(gtk.DrawingArea):
 
         gtk.DrawingArea.__init__(self)
 
-        self.add_events(gtk.gdk.BUTTON_PRESS_MASK)
+        self.add_events(gtk.gdk.BUTTON_PRESS_MASK | \
+                        gtk.gdk.PROPERTY_CHANGE_MASK)
 
         self._input_freq = input_frequency
         self.stroke_color = None
@@ -61,6 +62,9 @@ class DrawWaveform(gtk.DrawingArea):
         self.trigger_xpos = 0.0
         self.trigger_ypos = 0.5
 
+        self.active = False
+        self._redraw_atom = gtk.gdk.atom_intern('MeasureRedraw')
+
         self.buffers = np.array([])
         self.main_buffers = np.array([])
         self.str_buffer=''
@@ -208,11 +212,13 @@ class DrawWaveform(gtk.DrawingArea):
         if not self.context:
             self.handler_unblock(self.expose_event_id)
         self.context = True
+        self._indirect_queue_draw()
 
     def set_context_off(self):
         if self.context:
             self.handler_block(self.expose_event_id)
         self.context = False
+        self._indirect_queue_draw()
 
     def set_invert_state(self, invert_state):
         self.invert = invert_state
@@ -229,6 +235,16 @@ class DrawWaveform(gtk.DrawingArea):
         gtk.DrawingArea.do_size_allocate(self, allocation)
         self._update_mode()
 
+    def _indirect_queue_draw(self):
+        if self.window == None:
+            return
+        self.window.property_change(self._redraw_atom, self._redraw_atom,
+            32, gtk.gdk.PROP_MODE_REPLACE, []);
+
+    def do_property_notify_event(self, event):
+        if event.atom == self._redraw_atom:
+            self.queue_draw()
+
     def do_realize(self):
         gtk.DrawingArea.do_realize(self)
 
@@ -300,8 +316,9 @@ class DrawWaveform(gtk.DrawingArea):
 
     def _expose(self, widget, event):
         """This function is the "expose" event handler and does all the drawing"""
+
         #######################Real time drawing###################################
-        if self.context:
+        if self.context and self.active:
 
             #Iterate for each graph                                                            
             for graph_id in self.graph_id:                                          
@@ -310,6 +327,7 @@ class DrawWaveform(gtk.DrawingArea):
                     samples = math.ceil(self.allocation.width/self.draw_interval)
                     if len(buf) == 0:
                         # We don't have enough data to plot.
+                        self._indirect_queue_draw()
                         return
 
                     x_offset = 0
@@ -360,14 +378,20 @@ class DrawWaveform(gtk.DrawingArea):
                         Fs = 48000
                         nfft = 65536
 
-                        # Multiply input with the window
-                        np.multiply(buf, self.fft_window, buf)
-
-                        # Should be fast enough even without power of 2 stuff.
-                        self.fftx = np.fft.rfft(buf)
-                        self.fftx = abs(self.fftx)
-                        data = np.multiply(self.fftx, 0.02, self.fftx)
-                        ##################################
+                        try:
+                            # Multiply input with the window
+                            np.multiply(buf, self.fft_window, buf)
+
+                            # Should be fast enough even without power of 2 stuff.
+                            self.fftx = np.fft.rfft(buf)
+                            self.fftx = abs(self.fftx)
+                            data = np.multiply(self.fftx, 0.02, self.fftx)
+                            ##################################
+                        except ValueError:
+                            # TODO: Figure out how this can happen.
+                            #       Shape mismatch between window and buf
+                            self._indirect_queue_draw()
+                            return True
 
                     ################Scaling the values###################
                     if config.CONTEXT == 2:
@@ -402,7 +426,8 @@ class DrawWaveform(gtk.DrawingArea):
                     else:
                         self.window.draw_points(self._line_gc[graph_id], lines)
                     ############################################################
-                            
+
+            self._indirect_queue_draw()
         """
         ## DISPLAYING FRAMERATE FOR DEBUGGGIN
         fr = 1.0/( time.time()-self.pr_time)
@@ -486,6 +511,13 @@ class DrawWaveform(gtk.DrawingArea):
 
             self.fft_window = None
 
+    def set_active(self, active):
+        self.active = active
+        self._indirect_queue_draw()
+
+    def get_active(self):
+        return self.active
+
     def get_stroke_color_from_sugar(self):
         """Returns in (r,g,b) format the stroke color from the Sugar profile"""
         # Hitting gconf is a large overhead.
diff --git a/measure.py b/measure.py
index 45c8eff..e7d3a56 100644
--- a/measure.py
+++ b/measure.py
@@ -97,7 +97,7 @@ class MeasureActivity(activity.Activity):
 
         self.first = True
 
-        gobject.timeout_add(config.REFRESH_TIME, self.waveform_refresh)
+        self.wave.set_active(True)
 
     def set_show_hide_windows(self, window_id=1):
         """Shows the appropriate window identified by the window_id
@@ -127,10 +127,6 @@ class MeasureActivity(activity.Activity):
         If 1 is returned means camera context"""
         return self.active_context_status
 
-    def waveform_refresh(self):
-        self.wave.queue_draw()
-        return self.active_status
-
     def on_quit(self,data=None):	
         self.audiograb.on_activity_quit()	
         self.ji.on_quit()
@@ -145,9 +141,9 @@ class MeasureActivity(activity.Activity):
         elif (self.props.active and not self.ACTIVE):
 	        self.audiograb.resume_grabbing()
 	        self.active_status = True
-	        gobject.timeout_add(config.REFRESH_TIME, \
-		        self.waveform_refresh)
+
         self.ACTIVE = self.props.active
+        self.wave.set_active(self.ACTIVE)
 
     """
     Write the project to the Journal