如何在猕猴桃的单个屏幕上独立旋转两个矩形小部件？

Question

我正在学习python编程，并在一个简单的游戏应用程序上工作，在该应用程序中，我需要在单个屏幕上单击时旋转两个矩形，但是发生的事情是当我单击其中的两个矩形时，两个矩形都沿原点旋转那个被点击的矩形，但是另一个矩形不是这种情况，实际上，它的位置也不应该是那个矩形，当单击分配的位置（不存在该矩形）时，它旋转而不旋转两个矩形。我只需要在独立单击时旋转两个矩形即可。很难解释，所以请尝试执行代码并查找发生的情况。

from kivy.app import App
from kivy.graphics import Rotate, Rectangle, Ellipse, Color
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen, CardTransition
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty, NumericProperty, ReferenceListProperty, ListProperty
from kivy.uix.floatlayout import FloatLayout

Builder.load_string('''

<Stage_2>:
    object2: Object2
    object3: Object3

    Object2:
        id: Object2
        center: self.rotate_origin

    Object3:
        id: Object3
        center: self.rotate_origin

<Manager>:
    id: screen_manager

    Screen:
        name:"P"
        FloatLayout:

            Button:
                pos_hint:{"x":0.2,"y":0.05}
                size_hint: 0.6, 0.2
                font_size: (root.width**2 + root.height**2) / 13**4
                text: "Play"
                background_color: 255,0,1,1
                on_release:
                    root.transition.direction = "up"        
                    root.current = "stage2"

    Screen:
        name: 'stage2'
        Stage_2:
            id:s2

''')

class Object2(Widget):
    def __init__(self, *args, **kwargs):
        Widget.__init__(self, *args, **kwargs)
        self.rect_pos_x = 500
        self.rect_pos_y = 425
        self.rect_pos = self.rect_pos_x, self.rect_pos_y
        self.rect_width = 150
        self.rect_height = 30
        self.rect_size = self.rect_width, self.rect_height
        self.rotate_origin_x = self.rect_pos_x + self.rect_width / 2
        self.rotate_origin_y = self.rect_pos_y + self.rect_height / 2
        self.rotate_origin = self.rotate_origin_x, self.rotate_origin_y
        self.angle = 135
        print('rect 1')
        with self.canvas:
            Rotate(origin=self.rotate_origin, angle=self.angle)
            Color(rgb=(0,197,68))
            Rectangle(pos=self.rect_pos, size=self.rect_size)

    def rotate(self):
        self.canvas.clear()
        self.angle += 90
        if (self.angle > 315):
            self.angle = 225
        with self.canvas:
            Rotate(origin=self.rotate_origin, angle=self.angle)
            Color(rgb=(0, 255, 100))
            Rectangle(pos=self.rect_pos, size=self.rect_size)

    def on_touch_up(self, touch):
        if self.collide_point(*touch.pos):
            self.rotate()
            print(self.angle)
class Object3(Widget):
    def __init__(self, *args, **kwargs):
        Widget.__init__(self, *args, **kwargs)
        self.rect_pos_x = 500
        self.rect_pos_y = 250
        self.rect_pos = self.rect_pos_x, self.rect_pos_y
        self.rect_width = 150
        self.rect_height = 30
        self.rect_size = self.rect_width, self.rect_height
        self.rotate_origin_x = self.rect_pos_x + self.rect_width / 2
        self.rotate_origin_y = self.rect_pos_y + self.rect_height / 2
        self.rotate_origin = self.rotate_origin_x, self.rotate_origin_y
        self.angle = 135
        print('rect 2')
        with self.canvas:
            Rotate(origin=self.rotate_origin, angle=self.angle)
            Color(rgb=(1,255,0))
            Rectangle(pos=self.rect_pos, size=self.rect_size)

    def rotate(self):
        self.canvas.clear()
        self.angle += 90
        if (self.angle > 315):
            self.angle = 225
        with self.canvas:
            Rotate(origin=self.rotate_origin, angle=self.angle)
            Color(rgb=(0, 255, 100))
            Rectangle(pos=self.rect_pos, size=self.rect_size)

    def on_touch_up(self, touch):
        if self.collide_point(*touch.pos):
            self.rotate()
            print(self.angle)

class Stage_2(Widget):
    object2 = ObjectProperty(None)
    object3 = ObjectProperty(None)

class Manager(ScreenManager):
    pass

sm = Manager()

class ScreensApp(App):
    def build(self):
        return sm

if __name__ == '__main__':
    ScreensApp().run()

Answer 1

如果在PushMatrix()指令中包含PopMatrix()和canvas，则仅当前的Widget将受到影响。然后，如果将Widget size和pos调整为Rectangle，则应该会获得更好（但不是完美）的性能：

    with self.canvas:
        PushMatrix()
        Rotate(origin=self.rotate_origin, angle=self.angle)
        Color(rgb=(1,255,0))
        Rectangle(pos=self.rect_pos, size=self.rect_size)
        PopMatrix()
        self.pos = self.rect_pos
        self.size = self.rect_size

只要您使用涉及with self.canvas，Rotation或Scale的Translate，就需要这样做。 collide_point()仍将注视Widget size和pos，而不是Rectangle，但至少Widget及其Rectangle的中心应重合。