from PyQt5 import QtWidgets, uic
from PyQt5.QtWidgets import QTableWidgetItem, QMessageBox
from PyQt5.QtGui import QPen, QColor, QImage, QPixmap, QPainter, QTransform, QPolygonF
from PyQt5.QtCore import Qt, QTime, QCoreApplication, QEventLoop, QPointF
import copy
red = Qt.red
blue = Qt.blue
black = Qt.black
now = None
class Window(QtWidgets.QMainWindow):
def __init__(self):
QtWidgets.QWidget.__init__(self)
uic.loadUi("window.ui", self)
self.scene = Scene(0, 0, 561, 581)
self.scene.win = self
self.view.setScene(self.scene)
self.poly.clicked.connect(lambda : set_pol(self))
self.erase.clicked.connect(lambda: clean_all(self))
self.paint.clicked.connect(lambda: clipping(self))
self.rect.clicked.connect(lambda: set_rect(self))
self.ect.clicked.connect(lambda: add_bars(self))
self.lock.clicked.connect(lambda: lock(self))
self.clip = []
self.pol = []
self.point_now_clip = None
self.point_now_pol = None
self.point_lock_pol = None
self.point_lock_clip = None
self.input_pol = False
self.input_clip = False
self.pen = QPen(black)
class Scene(QtWidgets.QGraphicsScene):
def mousePressEvent(self, event):
add_point(event.scenePos())
def mouseMoveEvent(self, event):
global w
x = event.scenePos().x()
y = event.scenePos().y()
w.x.setText("{0}".format(x))
w.y.setText("{0}".format(y))
def sign(x):
if not x:
return 0
else:
return x / abs(x)
def set_pol(win):
if win.input_pol:
win.input_pol = False
win.rect.setDisabled(False)
win.erase.setDisabled(False)
win.paint.setDisabled(False)
win.ect.setDisabled(False)
else:
win.input_pol = True
win.rect.setDisabled(True)
win.erase.setDisabled(True)
win.paint.setDisabled(True)
win.ect.setDisabled(True)
def set_rect(win):
if win.input_clip:
win.input_clip = False
win.poly.setDisabled(False)
win.erase.setDisabled(False)
win.paint.setDisabled(False)
win.ect.setDisabled(False)
else:
win.input_clip = True
win.poly.setDisabled(True)
win.erase.setDisabled(True)
win.paint.setDisabled(True)
win.ect.setDisabled(True)
def add_point(point):
global w
if w.input_clip:
w.pen.setColor(black)
if w.point_now_clip is None:
w.point_now_clip = point
w.point_lock_clip = point
add_row(w.table_rect)
i = w.table_rect.rowCount() - 1
item_x = QTableWidgetItem("{0}".format(point.x()))
item_y = QTableWidgetItem("{0}".format(point.y()))
w.table_rect.setItem(i, 0, item_x)
w.table_rect.setItem(i, 1, item_y)
else:
w.clip.append(point)
w.point_now_clip = point
add_row(w.table_rect)
i = w.table_rect.rowCount() - 1
item_x = QTableWidgetItem("{0}".format(point.x()))
item_y = QTableWidgetItem("{0}".format(point.y()))
w.table_rect.setItem(i, 0, item_x)
w.table_rect.setItem(i, 1, item_y)
item_x = w.table_rect.item(i-1, 0)
item_y = w.table_rect.item(i-1, 1)
w.scene.addLine(point.x(), point.y(), float(item_x.text()), float(item_y.text()), w.pen)
if w.input_pol:
w.pen.setColor(blue)
if w.point_now_pol is None:
w.point_now_pol = point
w.point_lock_pol = point
add_row(w.table_pol)
i = w.table_pol.rowCount() - 1
item_x = QTableWidgetItem("{0}".format(point.x()))
item_y = QTableWidgetItem("{0}".format(point.y()))
w.table_pol.setItem(i, 0, item_x)
w.table_pol.setItem(i, 1, item_y)
else:
w.pol.append(point)
w.point_now_pol = point
add_row(w.table_pol)
i = w.table_pol.rowCount() - 1
item_x = QTableWidgetItem("{0}".format(point.x()))
item_y = QTableWidgetItem("{0}".format(point.y()))
w.table_pol.setItem(i, 0, item_x)
w.table_pol.setItem(i, 1, item_y)
item_x = w.table_pol.item(i-1, 0)
item_y = w.table_pol.item(i-1, 1)
w.scene.addLine(point.x(), point.y(), float(item_x.text()), float(item_y.text()), w.pen)
def lock(win):
if w.input_pol:
win.pol.append(win.point_lock_pol)
win.scene.addLine(win.point_now_pol.x(), win.point_now_pol.y(), win.point_lock_pol.x(), win.point_lock_pol.y(), w.pen)
win.point_now_pol = None
if w.input_clip:
win.clip.append(win.point_lock_clip)
win.scene.addLine(win.point_now_clip.x(), win.point_now_clip.y(), win.point_lock_clip.x(), win.point_lock_clip.y(), w.pen)
win.point_now_clip = None
def add_row(win_table):
win_table.insertRow(win_table.rowCount())
def clean_all(win):
win.scene.clear()
win.table_rect.clear()
win.table_pol.clear()
win.clip = []
win.pol = []
win.point_now_clip = None
win.point_now_pol = None
win.point_lock_clip = None
win.point_lock_pol = None
r = win.table_rect.rowCount()
for i in range(r, -1, -1):
win.table_rect.removeRow(i)
r = win.table_pol.rowCount()
for i in range(r, -1, -1):
win.table_pol.removeRow(i)
def isConvex(edges):
flag = 1
# начальные вершины
vo = edges[0] # iая вершина
vi = edges[1] # i+1 вершина
vn = edges[2] # i+2 вершина и все остальные
# векторное произведение двух векторов
x1 = vi.x() - vo.x()
y1 = vi.y() - vo.y()
x2 = vn.x() - vi.x()
y2 = vn.y() - vi.y()
# определяем знак ординаты
r = x1 * y2 - x2 * y1
prev = sign(r)
for i in range(2, len(edges) - 1):
if not flag:
break
vo = edges[i - 1]
vi = edges[i]
vn = edges[i + 1]
# векторное произведение двух векторов
x1 = vi.x() - vo.x()
y1 = vi.y() - vo.y()
x2 = vn.x() - vi.x()
y2 = vn.y() - vi.y()
r = x1 * y2 - x2 * y1
curr = sign(r)
# если знак предыдущей координаты не совпадает, то возможно многоугольник невыпуклый
if curr != prev:
flag = 0
prev = curr
# не забываем проверить последнюю с первой вершины
vo = edges[len(edges) - 1]
vi = edges[0]
vn = edges[1]
# векторное произведение двух векторов
x1 = vi.x() - vo.x()
y1 = vi.y() - vo.y()
x2 = vn.x() - vi.x()
y2 = vn.y() - vi.y()
r = x1 * y2 - x2 * y1
curr = sign(r)
if curr != prev:
flag = 0
return flag * curr
def is_intersection(ed1, ed2, norm):
vis1 = is_visiable(ed1[0], ed2[0], ed2[1], norm)
vis2 = is_visiable(ed1[1], ed2[0], ed2[1], norm)
if (vis1 and not vis2) or (not vis1 and vis2):
# ищем пересечение
p1 = ed1[0]
p2 = ed1[1]
q1 = ed2[0]
q2 = ed2[1]
delta = (p2.x() - p1.x()) * (q1.y() - q2.y()) - (q1.x() - q2.x()) * (p2.y() - p1.y())
delta_t = (q1.x() - p1.x()) * (q1.y() - q2.y()) - (q1.x() - q2.x()) * (q1.y() - p1.y())
if abs(delta) <= 1e-6:
return p2
t = delta_t / delta
I = QPointF()
I.setX(ed1[0].x() + (ed1[1].x() - ed1[0].x()) * t)
I.setY(ed1[0].y() + (ed1[1].y() - ed1[0].y()) * t)
return I
else:
return False
def is_visiable(point, peak1, peak2, norm):
v = vector([point, peak1], [peak2, peak1])
if norm * v < 0:
return True
else:
return False
def vector(v1, v2):
x1 = v1[0].x() - v1[1].x()
y1 = v1[0].y() - v1[1].y()
x2 = v2[0].x() - v2[1].x()
y2 = v2[0].y() - v2[1].y()
return x1 * y2 - x2 * y1
def clipping(win):
if len(win.clip) <= 1:
QMessageBox.warning(win, "Ошибка!", "Отсекатель не задан!")
if len(win.pol) <= 1:
QMessageBox.warning(win, "Ошибка!", "Многоугольник не задан!")
if len(win.pol) > 1 and len(win.clip) > 1:
norm = isConvex(win.clip)
if not norm:
QMessageBox.warning(win, "Ошибка!", "Отсекатель не выпуклый!Операция не может быть проведена!")
else:
p = sutherland_hodgman(win.clip, win.pol, norm)
if p:
win.pen.setWidth(2)
win.pen.setColor(red)
win.scene.addPolygon(p, win.pen)
win.pen.setWidth(1)
def sutherland_hodgman(clip, pol, norm):
# дублируем начальную вершину отсекателя в конец
clip.append(clip[0])
s = None
f = None
# цикл по вершинам отсекателя
for i in range(len(clip) - 1):
new = [] # новый массив вершин
for j in range(len(pol)): # цикл по вершинам многоугольника
if j == 0:
f = pol[j]
else:
t = is_intersection([s, pol[j]], [clip[i], clip[i + 1]], norm)
if t:
new.append(t)
s = pol[j]
if is_visiable(s, clip[i], clip[i + 1], norm):
new.append(s)
if len(new) != 0:
t = is_intersection([s, f], [clip[i], clip[i + 1]], norm)
if t:
new.append(t)
pol = copy.deepcopy(new)
if len(pol) == 0:
return False
else:
return QPolygonF(pol)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
w = Window()
w.show()
sys.exit(app.exec_())
