Added simple CPU usage visual

linux/caselights

@@ -5,6 +5,7 @@
 # - python-pyqt5
 # - python-pyserial
 
+import subprocess
 import sys
 import os.path
 import threading
@@ -34,6 +35,7 @@ class CaseLights():
 
     slowFadeUpdateFreq = 5
     fastFadeUpdateFreq = 20
+    cpuUsageUpdateFreq = 1
     fadeSaturation = 1.0
     fadeValue = 1.0
     fadeHueCounter = 0
@@ -81,6 +83,15 @@ class CaseLights():
         animMenu.addAction(fastFadeAction)
         self.menu.addMenu(animMenu)
 
+        visualMenu = QMenu("&Visualizations")
+        noVisualAction = QAction("Off")
+        noVisualAction.triggered.connect(self.animOff)
+        visualMenu.addAction(noVisualAction)
+        cpuUsageAction = QAction("CPU Usage")
+        cpuUsageAction.triggered.connect(self.cpuUsageOn)
+        visualMenu.addAction(cpuUsageAction)
+        self.menu.addMenu(visualMenu)
+
         lightMenu = QMenu("&UV-Light")
         lightOnAction = QAction("O&n")
         lightOnAction.triggered.connect(self.lightsOn)
@@ -105,7 +116,7 @@ class CaseLights():
             print("no icon found")
 
         icon = QIcon()
-        if iconPathName is not "":
+        if iconPathName != "":
             pic = QPixmap(32, 32)
             pic.load(iconPathName)
             icon = QIcon(pic)
@@ -210,6 +221,29 @@ class CaseLights():
         (r, g, b) = colorsys.hsv_to_rgb(h, s, v)
         return (round(r * 255), round(g * 255), round(b * 255))
 
+    def getCurrentCpuUsage(self):
+        # https://stackoverflow.com/a/9229692
+        # "top -bn1 | grep "Cpu(s)" | sed "s/.*, *\([0-9.]*\)%* id.*/\1/" | awk '{print 100 - $1}'"
+        # https://stackoverflow.com/a/4760517
+        cmd = ["top -bn1 | grep \"Cpu(s)\" | sed \"s/.*, *\\([0-9.]*\\)%* id.*/\\1/\" | awk '{print 100 - $1}'"]
+        result = subprocess.run(cmd, shell=True, stdout=subprocess.PIPE)
+        num = result.stdout.decode('utf-8')
+        return float(num)
+
+    def cpuUsageRunner(self):
+        while self.animationRunning is True:
+            cpu = self.getCurrentCpuUsage()
+            color = cpu / 100.0 * 120.0
+            (r, g, b) = self.hsvToRgb((120.0 - color) / 360.0, self.fadeSaturation, self.fadeValue)
+            self.printRGBStrings(str(r), str(g), str(b))
+            time.sleep(1.0 / self.cpuUsageUpdateFreq)
+
+    def cpuUsageOn(self):
+        self.animOff()
+        self.animationRunning = True
+        self.animation = threading.Thread(target=self.cpuUsageRunner)
+        self.animation.start()
+
     def fadeRunner(self, freq):
         while self.animationRunning is True:
             self.fadeHueCounter += 1