如何旋转多边形？

Question

为什么：目前 trying/doing 一些深度学习的东西，对 python 来说是全新的。我们已经为我们的东西准备了一些代码运行。我们现在只想计算我们找到的 "things"。因为我们没有找到任何关于多只猫和多只狗的分类数据。我想用六边形创建一些随机生成的图像。

我怎么想让它们中的一些旋转。但是我不知道怎么办。

from graphics import *
from random import randint
import math

image_height = 1000
image_height = 1000;
def main():
    win = GraphWin("Window",image_height,image_height)
    win.setBackground(color_rgb(255, 255, 255))

    for _ in range(0,8):
          figure = drawahexagon(80)
         #figure = rotatePolygon(figure,randint(0,90))
          figure.draw(win)
    win.getMouse()
    win.close


def drawahexagon(length):
    x = randint(0, image_height-length)
    y = randint(0, image_height-length)
    poly = Polygon(Point(x+getRandom(0),y+getRandom(0)),
                   Point(x+length+getRandom(1),y+getRandom(1)),
                   Point(x+(length*1.5)+getRandom(0),y+(length/2)+getRandom(1)),
                   Point(x+length+getRandom(1),y+length+getRandom(1)),
                   Point(x+getRandom(0),y+length+getRandom(1)),
                   Point(x-(length/2)+getRandom(1),y+(length/2)+getRandom(0)))
    poly.setFill(color_rgb(255,0,0))
    return poly


def getRandom(base):
  if base == 0:
    foo = randint(0,5)
  else:
    foo = randint(3,10)
  return foo



main()

Answer 1

以下是如何将 my answer 中的技术和数学应用到一个类似的问题，可以完成您 "wanna" 的问题（如果您想围绕它们的中心点旋转它们）。

我用 graphics 模块的 5.0 版测试了它，我从以下网址下载：

http://mcsp.wartburg.edu/zelle/python/graphics.py

from graphics import *
from random import randint
from math import sin, cos, radians

image_height = 1000
image_height = 1000

def main():
    win = GraphWin("Window", image_height, image_height)
    win.setBackground(color_rgb(255, 255, 255))

    for _ in range(8):
          figure = drawahexagon(80)
          figure = rotatePolygon(figure, randint(0, 90))
          figure.draw(win)
    try:
        win.getMouse()  # causes graphics.GraphicsError: getMouse in closed window
    except GraphicsError:  # ignore error
        pass
    win.close()

def rotatePolygon(polygon, degrees):
    """ Rotate polygon the given angle about its center. """
    theta = radians(degrees)  # Convert angle to radians
    cosang, sinang = cos(theta), sin(theta)

    points = polygon.getPoints()
    # find center point of Polygon to use as pivot
    n = len(points)
    cx = sum(p.getX() for p in points) / n
    cy = sum(p.getY() for p in points) / n

    new_points = []
    for p in points:
        x, y = p.getX(), p.getY()
        tx, ty = x-cx, y-cy
        new_x = ( tx*cosang + ty*sinang) + cx
        new_y = (-tx*sinang + ty*cosang) + cy
        new_points.append(Point(new_x, new_y))

    rotated_ploygon = polygon.clone()  # clone to get current attributes
    rotated_ploygon.points = new_points
    return rotated_ploygon

def drawahexagon(length):
    x = randint(0, image_height-length)
    y = randint(0, image_height-length)
    poly = Polygon(Point(x+getRandom(0), y+getRandom(0)),
                   Point(x+length+getRandom(1), y+getRandom(1)),
                   Point(x+(length*1.5)+getRandom(0), y+(length/2)+getRandom(1)),
                   Point(x+length+getRandom(1), y+length+getRandom(1)),
                   Point(x+getRandom(0), y+length+getRandom(1)),
                   Point(x-(length/2)+getRandom(1), y+(length/2)+getRandom(0)))
    poly.setFill(color_rgb(255, 0, 0))
    return poly

def getRandom(base):
    if base == 0:
        foo = randint(0, 5)
    else:
        foo = randint(3, 10)
    return foo

main()

正如我在评论中提到的那样，以这种方式创建旋转的多边形——首先创建一个未旋转的多边形，克隆它，然后旋转副本——效率有点低，因为它可以通过先创建旋转的点然后再创建旋转的点来完成创建 Polygon.

这是一个执行此操作的实现：

def drawarotatedhexagon(length, degrees):
    x = randint(0, image_height-length)
    y = randint(0, image_height-length)
    points = [Point(x+getRandom(0), y+getRandom(0)),
              Point(x+length+getRandom(1), y+getRandom(1)),
              Point(x+(length*1.5)+getRandom(0), y+(length/2)+getRandom(1)),
              Point(x+length+getRandom(1), y+length+getRandom(1)),
              Point(x+getRandom(0), y+length+getRandom(1)),
              Point(x-(length/2)+getRandom(1), y+(length/2)+getRandom(0))]

    theta = radians(degrees)  # Convert angle to radians
    cosang, sinang = cos(theta), sin(theta)

    n = len(points)
    cx = sum(pt.getX() for pt in points) / n
    cy = sum(pt.getY() for pt in points) / n
    for pt in points:
        tx, ty = pt.getX()-cx, pt.getY()-cy
        nx = ( tx*cosang + ty*sinang) + cx
        ny = (-tx*sinang + ty*cosang) + cy
        pt.x, pt.y = nx, ny

    poly = Polygon(*points)
    poly.setFill(color_rgb(255, 0, 0))
    return poly

如何旋转多边形？

How to rotate a polygon?

python

graphics

polygon

zelle-graphics