updated IndexBuffer to use Initialize() methods instead of doing it all in the constructor

src/framework/graphics/indexbuffer.cpp

@@ -4,25 +4,10 @@
 
 #include <string.h>
 
-IndexBuffer::IndexBuffer(uint32_t numIndices, BOOL isStatic)
-	: BufferObject(BUFFEROBJECT_TYPE_INDEX, isStatic ? BUFFEROBJECT_USAGE_STATIC : BUFFEROBJECT_USAGE_DYNAMIC)
+IndexBuffer::IndexBuffer()
 {
 	STACK_TRACE;
 	m_currentIndex = 0;
-	Resize(numIndices);
-}
-
-IndexBuffer::IndexBuffer(const IndexBuffer *source)
-	: BufferObject(BUFFEROBJECT_TYPE_INDEX, source->GetUsage())
-{
-	STACK_TRACE;
-	ASSERT(source != NULL);
-	ASSERT(source->GetNumElements() > 0);
-
-	m_currentIndex = 0;
-	Resize(source->GetNumElements());
-
-	memcpy(&m_buffer[0], source->GetBuffer(), GetNumElements() * GetElementWidthInBytes());
 }
 
 IndexBuffer::~IndexBuffer()
@@ -30,6 +15,57 @@ IndexBuffer::~IndexBuffer()
 	STACK_TRACE;
 }
 
+BOOL IndexBuffer::Initialize(uint32_t numIndices, BUFFEROBJECT_USAGE usage)
+{
+	STACK_TRACE;
+	return Initialize(NULL, numIndices, usage);
+}
+
+BOOL IndexBuffer::Initialize(GraphicsDevice *graphicsDevice, uint32_t numIndices, BUFFEROBJECT_USAGE usage)
+{
+	STACK_TRACE;
+	ASSERT(m_buffer.size() == 0);
+	if (m_buffer.size() > 0)
+		return FALSE;
+
+	ASSERT(numIndices > 0);
+	if (numIndices == 0)
+		return FALSE;
+		
+	if (!BufferObject::Initialize(graphicsDevice, BUFFEROBJECT_TYPE_INDEX, usage))
+		return FALSE;
+	
+	Resize(numIndices);
+	
+	return TRUE;
+}
+
+BOOL IndexBuffer::Initialize(const IndexBuffer *source)
+{
+	STACK_TRACE;
+	return Initialize(NULL, source);
+}
+
+BOOL IndexBuffer::Initialize(GraphicsDevice *graphicsDevice, const IndexBuffer *source)
+{
+	STACK_TRACE;
+	ASSERT(m_buffer.size() == 0);
+	if (m_buffer.size() > 0)
+		return FALSE;
+
+	ASSERT(source != NULL);
+	if (source == NULL)
+		return FALSE;
+	
+	ASSERT(source->GetNumElements() > 0);
+	if (source->GetNumElements() == 0)
+		return FALSE;
+	
+	Resize(source->GetNumElements());
+	
+	memcpy(&m_buffer[0], source->GetBuffer(), GetNumElements() * GetElementWidthInBytes());	
+}
+
 void IndexBuffer::Set(const uint16_t *indices, uint32_t numIndices)
 {
 	STACK_TRACE;
@@ -39,6 +75,10 @@ void IndexBuffer::Set(const uint16_t *indices, uint32_t numIndices)
 void IndexBuffer::Resize(uint32_t numIndices)
 {
 	STACK_TRACE;
+	ASSERT(numIndices > 0);
+	if (numIndices == 0)
+		return;
+	
 	m_buffer.resize(numIndices, 0);
 
 	if (!IsClientSideBuffer())

src/framework/graphics/indexbuffer.h

@@ -7,6 +7,8 @@
 #include <stdlib.h>        // for abs()
 #include <stl/vector.h>
 
+class GraphicsDevice;
+
 /**
  * Wraps management of an array of vertex indexes to be used for
  * optimized rendering of vertices.
@@ -14,22 +16,43 @@
 class IndexBuffer : public BufferObject
 {
 public:
-	/**
-	 * Creates an index buffer.
-	 * @param numIndices the initial number of indices the buffer should hold
-	 * @param isStatic whether the index data is static or dynamic (used as
-	 *                 a hint for index data stored in video memory)
-	 */
-	IndexBuffer(uint32_t numIndices, BOOL isStatic);
-
-	/**
-	 * Creates an index buffer.
-	 * @param source the source buffer to copy during creation of this buffer
-	 */
-	IndexBuffer(const IndexBuffer *source);
-
+	IndexBuffer();
 	virtual ~IndexBuffer();
 	
+	/**
+	 * Initializes the index buffer.
+	 * @param numIndices the initial number of indices the buffer should hold
+	 * @param usage the expected usage pattern of this index buffer
+	 * @return TRUE if successful, FALSE if not
+	 */
+	BOOL Initialize(uint32_t numIndices, BUFFEROBJECT_USAGE usage);
+	
+	/**
+	 * Initializes the index buffer.
+	 * @param graphicsDevice the graphics device to use to create this buffer
+	 *                       on the GPU
+	 * @param numIndices the initial number of indices the buffer should hold
+	 * @param usage the expected usage pattern of this index buffer
+	 * @return TRUE if successful, FALSE if not
+	 */
+	BOOL Initialize(GraphicsDevice *graphicsDevice, uint32_t numIndices, BUFFEROBJECT_USAGE usage);
+	
+	/**
+	 * Initializes the index buffer.
+	 * @param source the source buffer to copy during creation of this buffer
+	 * @return TRUE if successful, FALSE if not
+	 */
+	BOOL Initialize(const IndexBuffer *source);
+	
+	/**
+	 * Initializes the index buffer.
+	 * @param graphicsDevice the graphics device to use to create this buffer
+	 *                       on the GPU
+	 * @param source the source buffer to copy during creation of this buffer
+	 * @return TRUE if successful, FALSE if not
+	 */
+	BOOL Initialize(GraphicsDevice *graphicsDevice, const IndexBuffer *source);
+
 	/**
 	 * Copies the source indices over top of this buffer's existing indices.
 	 * @param indices the source index data to copy