added and positioned an array of 8 knobs

knob.py

@@ -3,11 +3,11 @@ import math
 
 class Knob:
     
-    def __init__(self, screen):
+    def __init__(self, screen, color, radius, position):
         self.screen = screen
-        self.radius = screen.get_width()/20
-        self.fill_color = (160,0,255)
-        self.position = (screen.get_width()/2, screen.get_height()/2)
+        self.radius = radius
+        self.fill_color = color
+        self.position = position
         self.value = 0
 
     def set_value(self, value):

main.py

@@ -6,7 +6,20 @@ pygame.init()
 screenW = 561
 screenH = 325
 screen = pygame.display.set_mode((screenW, screenH))
-knob1 = Knob(screen)
+
+knobs_radius = screenW / 25
+knobs_spacing = knobs_radius * 2
+knobs_x = (screenW - (knobs_radius + knobs_spacing) * 2) / 2
+x = knobs_x
+knobs_y = (screenH - (knobs_radius + knobs_spacing) * 3) / 2
+y = knobs_y
+knobs = []
+for i in range(8):
+    knobs.append(Knob(screen, (0, 210, 200), knobs_radius, (x, y)))
+    y += knobs_radius + knobs_spacing
+    if i == 3 or i == 6:
+        x += knobs_radius + knobs_spacing
+        y = knobs_y
 
 clock = pygame.time.Clock()
 running = True
@@ -22,8 +35,10 @@ while running:
     screen.fill("black")
 
     # RENDER YOUR GAME HERE
-    knob1.display()
+    for i in range(8):
+        knobs[i].display()
 
+    pygame.draw.polygon(screen, "white", [(0, screenH/2), (screenW*3/19, screenH), (0, screenH)])
     # flip() the display to put your work on screen
     pygame.display.flip()