Examples: adding balls_demo.py

Author: thirdr

examples/balls_demo.py

@@ -0,0 +1,60 @@
+import random
+from interstate75 import Interstate75, DISPLAY_INTERSTATE75_128X128
+
+i75 = Interstate75(display=DISPLAY_INTERSTATE75_128X128)
+graphics = i75.display
+
+width = i75.width
+height = i75.height
+
+
+class Ball:
+    def __init__(self, x, y, r, dx, dy, pen):
+        self.x = x
+        self.y = y
+        self.r = r
+        self.dx = dx
+        self.dy = dy
+        self.pen = pen
+
+
+# initialise shapes
+balls = []
+for i in range(0, 75):
+    r = random.randint(0, 3) + 3
+    balls.append(
+        Ball(
+            random.randint(r, r + (width - 2 * r)),
+            random.randint(r, r + (height - 2 * r)),
+            r,
+            (7 - r) / 4,
+            (7 - r) / 4,
+            graphics.create_pen(random.randint(0, 255), random.randint(0, 255), random.randint(0, 255)),
+        )
+    )
+
+BG = graphics.create_pen(0, 0, 0)
+
+while True:
+    graphics.set_pen(BG)
+    graphics.clear()
+
+    for ball in balls:
+        ball.x += ball.dx
+        ball.y += ball.dy
+
+        xmax = width - ball.r
+        xmin = ball.r
+        ymax = height - ball.r
+        ymin = ball.r
+
+        if ball.x < xmin or ball.x > xmax:
+            ball.dx *= -1
+
+        if ball.y < ymin or ball.y > ymax:
+            ball.dy *= -1
+
+        graphics.set_pen(ball.pen)
+        graphics.circle(int(ball.x), int(ball.y), int(ball.r))
+
+    i75.update()