CYIMesh Class Reference

Detailed Description

Class representing an instance of geometry information.

A mesh represents 3D geometry using an array of vertices and indices. To facilitate vertex and index sharing, meshes may contain a matrix describing a specific transformation to be applied to the vertex data prior to rendering.

For instance, an application may make use of a single set of vertices to represent a sphere with diameter 1 and make use of this matrix to apply scaling to render spheres of varying sizes without requiring a different set of vertex data. This allows for rendering with fewer state changes and less overall video ram usage.

Using this matrix instead of the transform matrix of the node containing this mesh is beneficial because children of the node will not inherit the transformation, it will be applied only to the specific instance of the mesh.

#include <renderer/YiMesh.h>

Inheritance diagram for CYIMesh:

Classes
struct	YI_ATTRIBUTE_BINDING

Public Types
enum	YI_GEOMETRY_PRIMITIVE {   YI_TRIANGLES,   YI_TRIANGLE_STRIP,   YI_POINTS }
enum	YI_BUFFER_OWNERSHIP {   YI_BUFFER_OWNED,   YI_BUFFER_SHARED }

Public Member Functions
	CYIMesh ()
virtual	~CYIMesh ()
void	SetTransform (const glm::mat4 &transform)
const glm::mat4 &	GetTransform () const
uint32_t	AddVertexBuffer (const std::shared_ptr< CYIAssetBufferObjectData > &pData, YI_BUFFER_OWNERSHIP ownership)
void	SetIndexBuffer (const std::shared_ptr< CYIAssetBufferObjectData > &pData, YI_BUFFER_OWNERSHIP ownership)
void	SetBindings (const std::vector< YI_ATTRIBUTE_BINDING > &bindings)
const std::vector< YI_ATTRIBUTE_BINDING > &	GetBindings () const
void	SetAxisAlignedBoundingBox (const CYIAABB &aabb)
const CYIAABB &	GetAxisAlignedBoundingBox () const
const std::shared_ptr< CYIAssetBufferObjectData > &	GetVertexBuffer (uint32_t uBufferIndex) const
const std::shared_ptr< CYIAssetBufferObjectData > &	GetIndexBuffer () const
void	RemoveVertexBuffer (uint32_t uBufferIndex)
void	RemoveIndexBuffer ()
const YI_ATTRIBUTE_BINDING &	GetBinding (uint32_t uBindingIndex)
uint32_t	GetNumVertexBuffers () const
uint32_t	GetNumBindings () const
void	SetPrimitive (YI_GEOMETRY_PRIMITIVE primitive)
YI_GEOMETRY_PRIMITIVE	GetPrimitive () const
uint32_t	GetIndexCount () const
void	SetIndexCount (uint32_t count)
uint32_t	GetStartOffset () const
void	SetStartOffset (uint32_t uStartOffset)
void	SetDepthTesting (bool bEnabled)
bool	GetDepthTesting () const
bool	IsLoaded () const
Public Member Functions inherited from CYIScriptableObject
	CYIScriptableObject ()
	CYIScriptableObject (const CYIScriptableObject &other)
CYIScriptableObject &	operator= (const CYIScriptableObject &other)
virtual	~CYIScriptableObject ()
CYIBindingImplementation *	GetBindingImplementation () const
void	SetBindingImplementation (CYIBindingImplementation *pBindingImplementation)
virtual const CYIRuntimeTypeInfo *	GetRuntimeTypeInfoForScriptObject () const

Static Public Attributes
static const uint32_t	YI_POSITION = 0
static const uint32_t	YI_TEXCOORD = 1
static const uint32_t	YI_NORMAL = 2
static const uint32_t	YI_COLOR = 3

Protected Attributes
std::vector< std::shared_ptr< CYIAssetBufferObjectData > >	m_VBOs
std::shared_ptr< CYIAssetBufferObjectData >	m_IBO
std::vector< YI_ATTRIBUTE_BINDING >	m_Attributes
YI_GEOMETRY_PRIMITIVE	m_primitive
uint32_t	m_indexCount
uint32_t	m_uStartOffset
glm::mat4	m_transform
CYIAABB	m_AABB
bool	m_bHasDepth
std::vector< YI_BUFFER_OWNERSHIP >	m_VBOOwnership
YI_BUFFER_OWNERSHIP	m_IBOOwnership
bool	m_bIsLoaded

Member Enumeration Documentation

enum CYIMesh::YI_BUFFER_OWNERSHIP

Flag to determine the ownership of the VBOs and IBO. If the flag is se to YI_BUFFER_OWNED, This CYIMesh Instance will take responsibility for unloading the VBOs and IBOs from the GPU.

Enumerator
YI_BUFFER_OWNED
YI_BUFFER_SHARED

enum CYIMesh::YI_GEOMETRY_PRIMITIVE

The primitive to be used for rendering this mesh

Enumerator
YI_TRIANGLES
YI_TRIANGLE_STRIP
YI_POINTS

Constructor & Destructor Documentation

CYIMesh::CYIMesh

(

)

virtual CYIMesh::~CYIMesh ( )

virtual

Member Function Documentation

uint32_t CYIMesh::AddVertexBuffer	(	const std::shared_ptr< CYIAssetBufferObjectData > &	pData,
		YI_BUFFER_OWNERSHIP	ownership
	)

Function to provide a means of adding vertex data buffers to the mesh, these buffers can later be used to bind to vertex attributes using SetBinding().

This function will return the index at which the buffer resides, for use with GetBuffer() and SetBinding().

const CYIAABB& CYIMesh::GetAxisAlignedBoundingBox

(

)

const

Get the axis-aligned bounding box for this mesh.

const YI_ATTRIBUTE_BINDING& CYIMesh::GetBinding

(

uint32_t

uBindingIndex

)

Get the binding at the uBindingIndex specified

const std::vector<YI_ATTRIBUTE_BINDING>& CYIMesh::GetBindings

(

)

const

Get the currently set bindings

bool CYIMesh::GetDepthTesting

(

)

const

Returns true if this mesh has depth testing enabled, false otherwise. The default value is false.

const std::shared_ptr<CYIAssetBufferObjectData>& CYIMesh::GetIndexBuffer

(

)

const

Get the index buffer

uint32_t CYIMesh::GetIndexCount

(

)

const

Get the number of indices used in the rendering of this mesh

uint32_t CYIMesh::GetNumBindings

(

)

const

Returns the number of attached bindings

uint32_t CYIMesh::GetNumVertexBuffers

(

)

const

Returns the number of attached vertex buffers

YI_GEOMETRY_PRIMITIVE CYIMesh::GetPrimitive

(

)

const

Get the primitive used for rendering this mesh.

uint32_t CYIMesh::GetStartOffset

(

)

const

Get the starting offset of vertices or indices used in the rendering of this mesh. The default value is 0.

See also

SetStartOffset

const glm::mat4& CYIMesh::GetTransform

(

)

const

Get the transformation matrix for this mesh.

const std::shared_ptr<CYIAssetBufferObjectData>& CYIMesh::GetVertexBuffer

(

uint32_t

uBufferIndex

)

const

Get the vertex buffer at the uBufferIndex specified.

bool CYIMesh::IsLoaded

(

)

const

Returns true if this mesh VBOs and IBO that are set are all loaded on the GPU, false otherwise.

void CYIMesh::RemoveIndexBuffer

(

)

Remove the index buffer

void CYIMesh::RemoveVertexBuffer

(

uint32_t

uBufferIndex

)

Remove the vertex buffer at the uBufferIndex specified.

void CYIMesh::SetAxisAlignedBoundingBox

(

const CYIAABB &

aabb

)

Set the axis-aligned bounding box for this mesh. It should tightly wrap the post-transform vertices of the mesh.

Warning

The user is responsible for including the mesh transform in the bounding box calculation if it is non-identity

void CYIMesh::SetBindings

(

const std::vector< YI_ATTRIBUTE_BINDING > &

bindings

)

Set the attribute bindings. This call will replace current bindings set internally.

void CYIMesh::SetDepthTesting

(

bool

bEnabled

)

Set whether this mesh should undergo depth testing. The depth test can be set via the IYIRenderer interface, this flag merely indicates that the mesh will undergo depth testing as configured in the renderer.

void CYIMesh::SetIndexBuffer	(	const std::shared_ptr< CYIAssetBufferObjectData > &	pData,
		YI_BUFFER_OWNERSHIP	ownership
	)

Function to set the index buffer for this mesh. Both an index buffer and one or more vertex buffers must be set and configured via SetBindings before a mesh can be successfully rendered

void CYIMesh::SetIndexCount

(

uint32_t

count

)

Set the number of vertices for this mesh, note that index in this context is not the same as a buffer index.

void CYIMesh::SetPrimitive

(

YI_GEOMETRY_PRIMITIVE

primitive

)

Set the primitive to be used for rendering this mesh. The vertices will be passed to the GPU using the specified geometry.

void CYIMesh::SetStartOffset

(

uint32_t

uStartOffset

)

Set the starting offset of vertices or indices for this mesh. Please note that if you you provide an index buffer, this offset will be used on the index buffer. If you do not provide an index buffer, the offset will be used on the vertex buffer(s) instead.

See also

GetStartOffset

void CYIMesh::SetTransform

(

const glm::mat4 &

transform

)

Set the transform matrix for this mesh. By default this is the identity matrix. This matrix will be applied to the vertices of the mesh prior to rendering, and is guaranteed to be the first matrix applied to the vertex data.

A typical use case is to allow the re-use of normalized vertex data across meshes of different sizes. For example, a 1x1 quad may be scaled up to NxM prior to rendering, allowing the user to make use of the same information across all of their quads instead of providing different vertex data for quads of varying sizes.

Warning

This transformation is not intended to be used in place of the scene node transformation functions, changes to this transformation will not propagate to the children of the node containing this mesh, the transform will only be applied to the internal vertices of this mesh, as specified by the buffers.

Member Data Documentation

CYIAABB CYIMesh::m_AABB

protected

std::vector<YI_ATTRIBUTE_BINDING> CYIMesh::m_Attributes

protected

bool CYIMesh::m_bHasDepth

protected

bool CYIMesh::m_bIsLoaded

mutableprotected

std::shared_ptr<CYIAssetBufferObjectData> CYIMesh::m_IBO

protected

YI_BUFFER_OWNERSHIP CYIMesh::m_IBOOwnership

protected

uint32_t CYIMesh::m_indexCount

protected

YI_GEOMETRY_PRIMITIVE CYIMesh::m_primitive

protected

glm::mat4 CYIMesh::m_transform

protected

uint32_t CYIMesh::m_uStartOffset

protected

std::vector<YI_BUFFER_OWNERSHIP> CYIMesh::m_VBOOwnership

protected

std::vector<std::shared_ptr<CYIAssetBufferObjectData> > CYIMesh::m_VBOs

protected

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The documentation for this class was generated from the following file:

• renderer/YiMesh.h