added worms demo

python_payload/demo_worms.py

+import hardware
+import random
+import time
+import math
+
+def xy_from_polar(r,deg):
+	#rad = deg/180*math.pi
+	
+	return( (
+		r * math.sin(deg), #x
+		r * math.cos(deg)  #y
+	)  )
+
+def randrgb():
+	return ((random.random(),random.random(),random.random()))
+	
+	
+WIDTH = 240
+HEIGHT = 240
+
+#Define a few RGB (0.0 to 1.0) colors
+BLACK = (0,0,0)
+RED = (1,0,0)
+GREEN = (0,1,0)
+BLUE = (0,0,1)
+WHITE = (1,1,1)
+GREY = (0.5,0.5,0.5)
+
+# Get the global context (representing the whole screen)
+global ctx
+ctx = hardware.get_ctx()
+
+#center the text horizontally and vertically
+ctx.text_align = ctx.CENTER
+ctx.text_baseline = ctx.MIDDLE
+
+#ctx.rgb() expects individual values for the channels, so unpack a list/tuple with *
+#operations on ctx can be chained
+#create a blue background
+ctx.rgb(*BLUE).rectangle(0,0,WIDTH,HEIGHT).fill()
+
+#Write some text
+ctx.move_to(WIDTH/2,HEIGHT/2).rgb(*WHITE).text("Hi :)")
+hardware.display_update()
+
+
+class Worm():
+	def __init__(self):
+		self.color = randrgb()
+		self.direction = random.random()*math.pi*2
+		self.size = random.randint(5,30)
+		self.speed = self.size/5
+		(x,y) = xy_from_polar(40, self.direction+90)
+		self.x = x
+		self.y= y
+		#(self.dx,self.dy) = xy_from_polar(1,self.direction)
+		self._lastdist = 0.0
+	
+	def draw(self):
+		ctx.rgb(*self.color)
+		ctx.round_rectangle(
+			WIDTH/2+self.x-self.size/2,
+			HEIGHT/2+self.y-self.size/2,
+			self.size,self.size,self.size//2
+		).fill()
+		
+	def mutate(self):
+		self.size += random.randint(-3,4)
+		self.color =  ([max(0,min(1,x+(random.random()*0.1-0.05))) for x in self.color])
+		
+		
+	
+	def move(self):
+		if self.size < 3:
+			self.size+=1
+			
+		if self.size > 30:
+			self.size-=1
+		
+		self.speed = min(3,self.size/4)	
+		#self.speed = self.size/5
+		
+		self.direction += (random.random()-0.5)*math.pi/4
+		
+		(dx,dy) = xy_from_polar(self.speed,self.direction)
+		self.x+=dx
+		self.y+=dy
+		
+		dist = math.sqrt(self.x**2+self.y**2)
+		if dist>110-self.size/2 and dist>self._lastdist:
+			polar_position=math.atan2(self.y,self.x)
+			dx=dx*-abs(math.cos(polar_position))
+			dy=dy*-abs(math.sin(polar_position))
+			self.direction=-math.atan2(dy,dx)
+			self.mutate()
+		self._lastdist = dist
+		
+worms = []
+
+for i in range(23):
+	worms.append(Worm())
+	
+
+while True:
+	for w in worms:
+		w.draw()
+		w.move()
+	
+	hardware.display_update()
+	time.sleep(0.001)
+print ("done")
+
+#Known problems:
+#ctx.rotate(math.pi) turns the display black until powercycled
+#ctx.clip() causes crashes
+