genesis-3d_engine/Engine/rendersystem/base/VertexLayout.h

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Copyright (c) 2007, Radon Labs GmbH
Copyright (c) 2011-2013,WebJet Business Division,CYOU
 
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#ifndef VERTEXLAYOUT_H
#define VERTEXLAYOUT_H

#include "core/refcounted.h"
#include "VertexComponent.h"
#include "util/stringatom.h"
namespace RenderBase
{
class VertexLayout : public Core::RefCounted
{
	__DeclareClass(VertexLayout);
public:
	/// constructor
	VertexLayout();
	/// destructor
	virtual ~VertexLayout();

	virtual void CopyFrom(const VertexLayout* vl);

	/// setup the vertex layout
	void Setup(const Util::Array<VertexComponent>& c);
	/// return true if valid has been setup
	bool IsValid() const;

	/// get number of components
	SizeT GetNumComponents() const;
	/// get vertex component at index
	const VertexComponent& GetComponentAt(IndexT i) const;
	/// return true if vertex component exists
	bool HasComponent(VertexComponent::SemanticName semName, IndexT semIndex) const;
	/// get index of vertex component by semantics
	IndexT FindComponent(VertexComponent::SemanticName semName, IndexT semIndex) const;
	/// get the vertex stride in number of bytes
	SizeT GetVertexByteSize() const;
	/// get vertex components
	const Util::Array<VertexComponent>& GetVertexComponents() const;   

		/// discard the vertex layout object
	void Discard();

	/// get sharing signature for a set of vertex components
	static Util::String BuildSignature(const Util::Array<VertexComponent>& c);
protected:
	friend class VertexBuffer;


	Util::Array<VertexComponent> components;
	SizeT vertexByteSize;
};

//------------------------------------------------------------------------------
/**
*/
inline bool
VertexLayout::IsValid() const
{
	return this->components.Size() > 0;
}

//------------------------------------------------------------------------------
/**
*/
inline SizeT
VertexLayout::GetNumComponents() const
{
	return this->components.Size();
}

//------------------------------------------------------------------------------
/**
*/
inline const VertexComponent&
VertexLayout::GetComponentAt(IndexT i) const
{
	return this->components[i];
}

//------------------------------------------------------------------------------
/**
*/
inline bool
VertexLayout::HasComponent(VertexComponent::SemanticName semName, IndexT semIndex) const
{
	return (InvalidIndex != this->FindComponent(semName, semIndex));
}

//------------------------------------------------------------------------------
/**
*/
inline SizeT
VertexLayout::GetVertexByteSize() const
{
	return this->vertexByteSize;
}

//------------------------------------------------------------------------------
/**
*/
inline
const Util::Array<VertexComponent>& 
VertexLayout::GetVertexComponents() const
{
	return this->components;
}

static Util::Dictionary<Util::StringAtom, GPtr<VertexLayout> > s_vertexLayouts;
/// create shared vertex layout object
static GPtr<VertexLayout> CreateSharedVertexLayout(const Util::Array<VertexComponent>& vertexComponents)
{
	n_assert(vertexComponents.Size() > 0);

	// get sharing signature from vertex components
	Util::StringAtom signature = VertexLayout::BuildSignature(vertexComponents);
	if (s_vertexLayouts.Contains(signature))
	{
		// return existing instance
		return s_vertexLayouts[signature];
	}
	else
	{
		// create new instance
		GPtr<VertexLayout> newVertexLayout = VertexLayout::Create();
		newVertexLayout->Setup(vertexComponents);
		s_vertexLayouts.Add(signature, newVertexLayout);
		return newVertexLayout;
	}
}
}

#endif//VERTEXLAYOUT_H