class Renderer;
+/**
+Base class for renderable objects. All Renderables must support rendering with
+a Renderer, and may optionally provide support for standalone rendering.
+
+The render methods take a Tag to identify a render pass. It is most commonly
+used together with Techniques and Pipelines to implement multipass rendering.
+*/
class Renderable
{
protected:
public:
virtual ~Renderable() { }
- /** Returns a key used for grouping Renderables in an InstanceScene. */
+ /** Returns a key used for grouping Renderables in an InstanceScene. The
+ returned value is treated as opaque. */
virtual long get_instance_key() const { return 0; }
+ /** Renders the renderable without a renderer. This can be convenient in
+ some simple cases, but most renderables don't need to implement this
+ method. */
virtual void render(const Tag & = Tag()) const;
- virtual void render(Renderer &, const Tag & = Tag()) const;
+
+ /** Renders the renderable. Implementors should take care to return the
+ renderer to the state it was in, for example by using Renderer::Push. */
+ virtual void render(Renderer &, const Tag & = Tag()) const = 0;
};
} // namespace Msp