Added visualization program for test/debugging purposes.

src/draw.py

+#!/usr/bin/env python
+import pygame, sys, time
+from touch import add, MultiTouchListener
+from math import degrees, cos, sin
+
+from events import RotateEvent
+
+pygame.init()
+
+# Config
+FINGER_RADIUS = 20
+CENTROID_RADIUS = 15
+W, H = 640, 480
+
+BG_COLOR = 0, 0, 0
+LINE_COLOR = 128, 128, 128
+CIRCLE_COLOR = 255, 255, 255
+RECT_COLOR = 0, 200, 0
+RECT_SIZE = 150, 100
+RECT_POS = W / 2, H / 2
+
+
+# Create canvas GUI in the current thread
+screen = pygame.display.set_mode((W, H))
+rotations = [RotateEvent(W / 2, H / 2, 70, 2)]
+#rotations = []
+#x, y, w, h = RECT_SIZE
+#rect = [(x, y), (x, y + h), (x + w, y + h), (x + w, y)]
+
+
+def rotate_point(point, axis, angle):
+    px, py = point
+    ax, ay = axis
+    x, y = px - ax, py - ay
+    radius = (x * x + y * y) ** .5
+
+    return ax + radius * cos(angle), ay + radius * sin(angle)
+
+
+def coord(x, y):
+    return int(round(W * x)), int(round(H * y))
+
+
+# Rotated rectangle
+angle = 0
+scale = 1
+
+def update():
+    global rotations
+    cx, cy = coord(*listener.centroid)
+
+    # Clear previous frame
+    screen.fill(BG_COLOR)
+
+    # Apply rotation to rectangle canvas
+    canvas = pygame.Surface((W, H))
+    canvas.fill(BG_COLOR)
+    pygame.draw.rect(canvas, RECT_COLOR, RECT_POS + RECT_SIZE)
+
+    scaled_canvas = pygame.transform.scale(canvas, coord(scale, scale))
+    rotated_canvas = pygame.transform.rotate(scaled_canvas, degrees(angle))
+    rect = rotated_canvas.get_rect()
+    rect.center = W / 2, H / 2
+    screen.blit(rotated_canvas, rect)
+
+    # Draw touch points
+    for p in listener.points:
+        x, y = coord(p.x, p.y)
+
+        # Draw line to centroid
+        pygame.draw.line(screen, LINE_COLOR, (x, y), (cx, cy), 1)
+
+        # Draw outlined circle around touch point
+        pygame.draw.circle(screen, CIRCLE_COLOR, (x, y), FINGER_RADIUS, 1)
+
+    # Draw filled circle around centroid
+    pygame.draw.circle(screen, CIRCLE_COLOR, (cx, cy), CENTROID_RADIUS)
+
+    # Update canvas
+    pygame.display.flip()
+
+def rotate(event):
+    global angle
+    angle += event.angle
+
+def pinch(event):
+    global scale
+    scale += event.amount
+
+
+# Start touch event listener in separate thread
+listener = MultiTouchListener(verbose=1, tuio_verbose=0)
+listener.bind('rotate', rotate)
+listener.bind('pinch', pinch)
+listener.start(threaded=True)
+
+# Start GUI event loop
+try:
+    while True:
+        for event in pygame.event.get():
+            if event.type == pygame.QUIT:
+                sys.exit()
+
+        update()
+except KeyboardInterrupt:
+    pass
+finally:
+    print 'Stopping program...'