void SpriteRenderer::UpdateBuffer(const GameContext& gameContext)
{
	UNREFERENCED_PARAMETER(gameContext);

	//TODO:
	// if the vertex buffer does not exists, or the number of sprites is bigger then the buffer size
	//		release the buffer
	//		update the buffer size (if needed)
	//		Create a new buffer. Make sure the Usage flag is set to Dynamic, you bind to the vertex buffer
	//		and you set the cpu access flags to access_write
	//
	//		Finally create the buffer. You can use the device in the game context. Be sure to log the HResult!

	if (!m_pVertexBuffer)
	{
		if(m_pVertexBuffer != nullptr)
			m_pVertexBuffer->Release();

		D3D11_BUFFER_DESC buffDesc;
		buffDesc.Usage = D3D11_USAGE_DYNAMIC;
		buffDesc.ByteWidth = sizeof(SpriteVertex) * m_Sprites.size(); //update the size? this updates the size or am I not getting it right? 
		buffDesc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
		buffDesc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
		buffDesc.MiscFlags = 0;

		const auto hr = gameContext.pDevice->CreateBuffer(&buffDesc, nullptr, &m_pVertexBuffer);
		if (Logger::LogHResult(hr, L"SpriteRenderer::UpdateBuffer > m_pVertexBuffer creation failed!"))
			return;
	}


	//------------------------
	//Sort Sprites
	//SORT BY TEXTURE
	sort(m_Sprites.begin(), m_Sprites.end(), [](const SpriteVertex& v0, const SpriteVertex& v1)
	{
		return v0.TextureId < v1.TextureId;
	});

	//SORT BY DEPTH
	sort(m_Sprites.begin(), m_Sprites.end(), SpriteSortByDepth);
	sort(m_Sprites.begin(), m_Sprites.end(), [](const SpriteVertex& v0, const SpriteVertex& v1)
	{
		if (v0.TextureId == v1.TextureId)
		{
			return v0.TransformData.z < v1.TransformData.z;
		}

		return false;
	});
	//------------------------

	//TODO: Fill Buffer
	// Finally fill the  buffer. You will need to create a D3D11_MAPPED_SUBRESOURCE
	// Next you will need to use the device context to map the vertex buffer to the mapped resource
	// use memcpy to copy all our sprites to the mapped resource
	// unmap the vertex buffer

	if (!m_pVertexBuffer)
	{
		D3D11_MAPPED_SUBRESOURCE mappedResource;
		gameContext.pDeviceContext->Map(m_pVertexBuffer, 0, D3D11_MAP_WRITE_NO_OVERWRITE, 0, &mappedResource);
		memcpy(mappedResource.pData, &m_Sprites, sizeof(SpriteVertex) * m_Sprites.size());
		gameContext.pDeviceContext->Unmap(m_pVertexBuffer, 0);
		//m_ImmediateVertex = m_Sprites;
	}


}