Beispiel #1
0
def Hull2D (P, m, H):

	#print m, H
	lines = []
	n = len (P)
	CHs = []
	num = n/m

	a = 0
	while a < n:
		b = min (a+m, n)
		l = P[a:b]
		ids = []
		for p in l: ids.append (p.hilight ())
		ch = Graham (l)
		#ch.hide ()
		for p in P[a:b]: p.unhilight (ids.pop ())
		CHs.append (ch)
		a = b

	i0 = 0
	# encontrando o ponto mais a direita
	p0 = CHs[0].pts
	for ch in CHs:
		for p in ch.to_list ():
			if p.x > p0.x: p0 = p
			elif p.x == p0.x: 
				if p.x > p0.x: p0 = p
	
	fecho = [ p0 ]
	for ch in CHs: ch.hide ()
	#control.sleep (2)
	for k in range (0, H):
		Q = []
		for ch in CHs:
			ch.plot ()
			p = ch.pts
			initial = 1
			while 1:
				direction = area2 (fecho[-1], p, p.next)
				if direction < 0:
					p = p.next
					initial = 0
				elif direction == 0 \
					and dist2 (fecho[-1], p) \
					    < dist2 (fecho[-1], p.next):
					p = p.next
					initial = 0
				elif initial:
					p = p.next
				else:
					Q.append (p)
					p.hilight ()
					control.sleep ()
					ch.pts = p.prev
					ch.hide ()
					break
			

		control.sleep ()
		p = Q[0]
		for q in Q[1:]:
			direction = area2 (fecho[-1], p, q)
			if direction < 0:
				p = q
			elif direction == 0:
				if (dist2 (fecho[-1], p) < dist2 (fecho[-1], q)):
					p = q

		for q in Q: q.unhilight ()
		lines.append (fecho[-1].lineto (p, 'green'))
		fecho.append (p)
		if p == p0: 
			#for ch in CHs: ch.hide ()
			#print 'fecho =',`fecho`
			fecho.pop ()
			for i in lines:
				control.plot_delete (i)
			poly = Polygon (fecho)
			poly.plot ()
			return poly
	
	#for ch in CHs: ch.hide ()
	for i in lines:
		control.plot_delete (i)
	return None
def Diameter (l):
	"""Algoritmo Diametro para encontrar o par de pontos mais distantes

	Ele consiste de:
	- determinar o fecho convexo dos pontos passados
	- determinar o conjunto de pares antipodas do fecho convexo
	- determinar o par antipoda cujos pontos estao a uma distancia maxima
	"""

	if len (l) < 2: return None
	if len (l) == 2:
		ret = Segment (l[0], l[1])
		ret.extra_info = 'distancia: %.2f'%math.sqrt (dist2 (l[0], l[1]))
		return ret
	
	ch = Graham (l)
	ch.hide ()
	ch.plot (config.COLOR_ALT4)

	control.sleep ()

	pairs = antipodes (ch)
	cores = (config.COLOR_ALT1,)

	#print `pairs`

	i=0
	for p,q in pairs:
		p.hilight (cores[i])
		q.hilight (cores[i])
		p.lineto (q, cores[i])
		i = (i+1) % len (cores)

	control.sleep ()

	farthest = dist2 (pairs[0][0], pairs[0][1])
	a = pairs[0][0]
	b = pairs[0][1]
	hia = a.hilight ()
	hib = b.hilight ()
	id = a.lineto (b)

	for i in range (1, len (pairs)):
		dist = dist2 (pairs[i][0], pairs[i][1])
		if dist > farthest:
			control.freeze_update ()
			a.unhilight (hia)
			b.unhilight (hib)
			control.plot_delete (id)

			farthest = dist
			a = pairs[i][0]
			b = pairs[i][1]

			hia = a.hilight ()
			hib = b.hilight ()
			id = a.lineto (b)
			control.thaw_update ()
	
	ret = Segment (a, b)
	ret.extra_info = 'distancia: %.2f'%math.sqrt (farthest)
	return ret
Beispiel #3
0
def Diameter(l):
    """Algoritmo Diametro para encontrar o par de pontos mais distantes

	Ele consiste de:
	- determinar o fecho convexo dos pontos passados
	- determinar o conjunto de pares antipodas do fecho convexo
	- determinar o par antipoda cujos pontos estao a uma distancia maxima
	"""

    if len(l) < 2: return None
    if len(l) == 2:
        ret = Segment(l[0], l[1])
        ret.extra_info = 'distancia: %.2f' % math.sqrt(dist2(l[0], l[1]))
        return ret

    ch = Graham(l)
    ch.hide()
    ch.plot(config.COLOR_ALT4)

    control.sleep()

    pairs = antipodes(ch)
    cores = (config.COLOR_ALT1, )

    #print `pairs`

    i = 0
    for p, q in pairs:
        p.hilight(cores[i])
        q.hilight(cores[i])
        p.lineto(q, cores[i])
        i = (i + 1) % len(cores)

    control.sleep()

    farthest = dist2(pairs[0][0], pairs[0][1])
    a = pairs[0][0]
    b = pairs[0][1]
    hia = a.hilight()
    hib = b.hilight()
    id = a.lineto(b)

    for i in range(1, len(pairs)):
        dist = dist2(pairs[i][0], pairs[i][1])
        if dist > farthest:
            control.freeze_update()
            a.unhilight(hia)
            b.unhilight(hib)
            control.plot_delete(id)

            farthest = dist
            a = pairs[i][0]
            b = pairs[i][1]

            hia = a.hilight()
            hib = b.hilight()
            id = a.lineto(b)
            control.thaw_update()

    ret = Segment(a, b)
    ret.extra_info = 'distancia: %.2f' % math.sqrt(farthest)
    return ret
Beispiel #4
0
def Hull2D (P, m, H):

	#print m, H
	lines = []
	n = len (P)
	CHs = []
	num = n/m

	a = 0
	while a < n:
		b = min (a+m, n)
		l = P[a:b]
		ids = []
		for p in l: ids.append (p.hilight ())
		ch = Graham (l)
		#ch.hide ()
		for p in P[a:b]: p.unhilight (ids.pop ())
		CHs.append (ch)
		a = b

	i0 = 0
	# encontrando o ponto mais a direita
	p0 = CHs[0].pts
	for ch in CHs:
		for p in ch.to_list ():
			if p.x > p0.x: p0 = p
			elif p.x == p0.x: 
				if p.x > p0.x: p0 = p
	
	fecho = [ p0 ]
	for ch in CHs: ch.hide ()
	#control.sleep (2)
	for k in range (0, H):
		Q = []
		for ch in CHs:
			ch.plot ()
			p = ch.pts
			initial = 1
			while 1:
				direction = area2 (fecho[-1], p, p.next)
				if direction < 0:
					p = p.next
					initial = 0
				elif direction == 0 \
					and dist2 (fecho[-1], p) \
					    < dist2 (fecho[-1], p.next):
					p = p.next
					initial = 0
				elif initial:
					p = p.next
				else:
					Q.append (p)
					p.hilight ()
					control.sleep ()
					ch.pts = p.prev
					ch.hide ()
					break
			

		control.sleep ()
		p = Q[0]
		for q in Q[1:]:
			direction = area2 (fecho[-1], p, q)
			if direction < 0:
				p = q
			elif direction == 0:
				if (dist2 (fecho[-1], p) < dist2 (fecho[-1], q)):
					p = q

		for q in Q: q.unhilight ()
		lines.append (fecho[-1].lineto (p, 'green'))
		fecho.append (p)
		if p == p0: 
			#for ch in CHs: ch.hide ()
			#print 'fecho =',`fecho`
			fecho.pop ()
			for i in lines:
				control.plot_delete (i)
			poly = Polygon (fecho)
			poly.plot ()
			return poly
	
	#for ch in CHs: ch.hide ()
	for i in lines:
		control.plot_delete (i)
	return None