C++: doubts about visitor pattern

Question

I know what Visitor Pattern is and how to use it; this question is not a duplicate of this one.

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I\'ve got a library where I put most of the reusable code I write,

Answer 1

There a many possible solutions, but you could do this, for example: Start new hierarchy, which renders Shapes in a specific Context:

// contracts:

class RenderingContext {
public: virtual void DrawLine(const Point&, const Point&) = 0; 
    // and so on...
};

class ShapeRenderer {
public: virtual void Render(RenderingContext&) = 0;
};

// implementations:

class RectangleRenderer : public ShapeRenderer {
 Rectangle& mR;

public: 
 virtual void Render(RenderingContext& pContext) {
   pContext.DrawLine(mR.GetLeftLower(), mR.GetRightLower());
   // and so on...
 }

 RectangleRenderer(Rectangle& pR) : mR(pR) {}
};