1 files changed, 153 insertions, 0 deletions
diff --git a/engine/MaterialBuckets.h b/engine/MaterialBuckets.h
new file mode 100644
index 0000000..70b0153
--- /dev/null
+++ b/engine/MaterialBuckets.h
@@ -0,0 +1,153 @@
+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: This is a helper class for the situation where you want to build lists of 
+// things that fall into buckets, and effeciently keep up with which buckets have
+// been used since flush.
+//
+//=============================================================================//
+
+#ifndef MATERIALBUCKETS_H
+#define MATERIALBUCKETS_H
+#ifdef _WIN32
+#pragma once
+#endif
+
+// FLASHLIGHTFIXME: Make all of the buckets share the same m_Elements (ie. make m_Elements static)
+
+template <class Element_t>
+class CMaterialsBuckets
+{
+public:
+	typedef unsigned short SortIDHandle_t;
+	typedef unsigned short ElementHandle_t;
+	CMaterialsBuckets()
+	{
+		m_FlushCount = -1;
+	}
+
+	// Set the number of buckets that are needed.  This should get called every time 
+	// a level is loaded.
+	void SetNumMaterialSortIDs( int n )
+	{
+		m_MaterialSortInfoArray.Purge();
+		m_MaterialSortInfoArray.SetCount( n );
+		m_Elements.Purge();
+
+		m_UsedSortIDs.Purge();
+	}
+
+	// Clear out all buckets.  This should get called once a frame.
+	void Flush( void )
+	{
+		m_FlushCount++;
+		m_Elements.RemoveAll();
+		m_UsedSortIDs.RemoveAll();
+	}
+
+	//
+	// These functions are used to get at the list of used buckets.
+	//
+	SortIDHandle_t GetFirstUsedSortID()
+	{
+		return m_UsedSortIDs.Head();
+	}
+
+	SortIDHandle_t GetNextUsedSortID( SortIDHandle_t prevSortID )
+	{
+		return m_UsedSortIDs.Next( prevSortID );
+	}
+
+	int GetSortID( SortIDHandle_t handle )
+	{
+		return m_UsedSortIDs[handle];
+	}
+	
+	SortIDHandle_t InvalidSortIDHandle()
+	{
+		return m_UsedSortIDs.InvalidIndex();
+	}
+
+
+	//
+	// These functions are used to get at the list of elements for each sortID.
+	//
+	ElementHandle_t GetElementListHead( int sortID )
+	{
+		return m_MaterialSortInfoArray[sortID].m_Head;
+	}
+
+	ElementHandle_t GetElementListNext( ElementHandle_t h )
+	{
+		return m_Elements.Next( h );
+	}
+
+	Element_t GetElement( ElementHandle_t h )
+	{
+		return m_Elements[h];
+	}
+
+	ElementHandle_t InvalidElementHandle()
+	{
+		return m_Elements.InvalidIndex();
+	}
+
+
+	// Add an element to the the bucket specified by sortID
+	void AddElement( int sortID, Element_t elem )
+	{
+		// Allocate an element to stick this in.
+		unsigned short elemID = m_Elements.Alloc( true );
+		m_Elements[elemID] = elem;
+		
+		if( m_MaterialSortInfoArray[sortID].m_FlushCount != m_FlushCount )
+		{
+			// This is the first element that has used this sort id since flush.
+			// FLASHLIGHTFIXME: need to sort these by vertex format when shoving
+			// them into this list!
+
+			// Mark this sortID as having been used since the last flush.
+			m_MaterialSortInfoArray[sortID].m_FlushCount = m_FlushCount;
+
+			// Add this sortID to the list of sortIDs used since flush.
+			m_UsedSortIDs.AddToTail( sortID );
+
+			// Set the head pointer for this sort id to this element.
+			m_MaterialSortInfoArray[sortID].m_Head = elemID;
+		}
+		else
+		{
+			// We already have an element in this sort id since flush, so chain
+			// into thelist of elements for this sort id.
+			m_Elements.LinkBefore( m_MaterialSortInfoArray[sortID].m_Head, elemID );
+			m_MaterialSortInfoArray[sortID].m_Head = elemID;
+		}
+	}
+
+private:
+	
+	struct MaterialSortInfo_t
+	{
+		MaterialSortInfo_t() :
+			m_FlushCount( -1 ),
+			m_Head( (unsigned short)-1 )  // i.e., InvalidIndex()
+		{
+		}
+		
+		int m_FlushCount;
+		unsigned short m_Head;
+	};
+	
+	// This is a list of material sort info ids that have been used since flush.
+	CUtlLinkedList<unsigned short> m_UsedSortIDs;
+
+	// This is m_NumMaterialSortIDs big.
+	CUtlVector<MaterialSortInfo_t> m_MaterialSortInfoArray;
+	
+	// This is used in multilist mode to make elements that belong in the multiple lists of 
+	CUtlLinkedList<Element_t, unsigned short, true> m_Elements;
+
+	int m_FlushCount;
+		
+};
+
+#endif // MATERIALBUCKETS_H