el

ellipse.py

@@ -0,0 +1,85 @@
+import math
+
+import kivy
+from kivy.app import App
+from kivy.core.image import Texture
+from kivy.factory import Factory
+from kivy.graphics.vertex_instructions import Ellipse
+from kivy.lang import Builder
+from kivy.properties import NumericProperty, ObjectProperty
+from kivy.uix.label import Label
+from kivy.uix.widget import Widget
+
+
+class MyWidget(Widget):
+    pass
+
+
+class MyTexture(Widget):
+    radius = NumericProperty(100)
+    texture = ObjectProperty(None, allownone=True)
+
+    #    @staticmethod
+    #    def generate_texture():
+
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+        self.bind(size=self.redraw)
+        self.cbuffer = None
+        self.redraw()
+
+    @staticmethod
+    def draw_circle(height, width):
+
+        r = min(height / 2, width / 2) - 5
+        center = r
+
+        arr = [[[0, 1, 0, 1] for _ in range(height)] for _ in range(width)]
+        n = 1000
+        for i in range(n):
+            dr = 2 * math.pi * i / n
+            x, y = round(center + r * math.cos(dr)), round(center + r * math.sin(dr))
+            arr[y][x] = [1, 0, 0, 1]
+        l = sum([sum(r, []) for r in arr], [])
+        return "".join(chr(round(a*255)) for a in l).encode()
+
+    def redraw(self, *args):
+        width, height = self.size
+        self.cbuffer = self.draw_circle(width, height)  # b"\xff\x66\x99\xff" * width * height
+        self.texture = Texture.create(size=(width, height), colorfmt="rgba", bufferfmt="ubyte")
+        self.texture.add_reload_observer(self.populate_texture)
+        self.populate_texture(self.texture)
+
+    def populate_texture(self, texture):
+        texture.blit_buffer(self.cbuffer, colorfmt="rgba", bufferfmt="ubyte")
+
+
+KV = """
+
+<MyTexture>:
+    canvas.before:
+        Rectangle:
+            pos: root.pos
+            texture: root.texture
+
+<MyWidget>:
+    canvas:
+        Color:
+            rgba: (1,0,0,1)
+        Ellipse:
+            pos: 100,100
+            size: 50,50
+    MyTexture:
+        pos: 300,300
+        size: 100,200            
+"""
+Builder.load_string(KV)
+
+
+class MyApp(App):
+    def build(self):
+        return MyWidget()
+
+
+if __name__ == "__main__":
+    MyApp().run()