Build Shapes with Swappable RenderersStep 2 of 5

Bridge a Circle to its renderer

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Step 2 - Bridge a Circle to its renderer

Now add the abstraction side. A Shape holds a reference to a Renderer (the bridge) rather than inheriting from it. That reference is the whole trick: the Shape never knows which backend it is talking to.

Implement Circle.draw so it delegates to the bound renderer by calling self.renderer.render_circle(self.radius) and returning the result. The same Circle logic then works with any renderer you pass in.

Hints
Starter code
class Renderer:
    def render_circle(self, radius):
        raise NotImplementedError

class VectorRenderer(Renderer):
    def render_circle(self, radius):
        return "vector circle r=" + str(radius)

class RasterRenderer(Renderer):
    def render_circle(self, radius):
        return "raster pixels for circle r=" + str(radius)

class Shape:
    def __init__(self, renderer):
        self.renderer = renderer
    def draw(self):
        raise NotImplementedError

class Circle(Shape):
    def __init__(self, renderer, radius):
        super().__init__(renderer)
        self.radius = radius
    def draw(self):
        """Draw this circle by delegating to the bound renderer."""
        # TODO: call self.renderer.render_circle(self.radius) and return it
        pass
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