ParaEngine::CBufferPicking Struct Reference

picking from frame buffer (back buffer) When there is picking query, it will render scene again (if out dated) with a special shader and read pixels from the back buffer. More...

#include <BufferPicking.h>

Inheritance diagram for ParaEngine::CBufferPicking:

Public Member Functions
	CBufferPicking (const AssetKey &key)
	ATTRIBUTE_DEFINE_CLASS (CBufferPicking)
virtual int	InstallFields (CAttributeClass *pClass, bool bOverride)
	this class should be implemented if one wants to add new attribute. More...
virtual IAttributeFields *	GetChildAttributeObject (const std::string &sName)
	get attribute by child object. More...
virtual int	GetChildAttributeObjectCount (int nColumnIndex=0)
	get the number of child objects (row count) in the given column. More...
virtual int	GetChildAttributeColumnCount ()
	we support multi-dimensional child object. More...
virtual IAttributeFields *	GetChildAttributeObject (int nRowIndex, int nColumnIndex=0)
	ATTRIBUTE_METHOD1 (CBufferPicking, GetPickingCount_s, int *)
	ATTRIBUTE_METHOD1 (CBufferPicking, GetPickingID_s, DWORD *)
	ATTRIBUTE_METHOD1 (CBufferPicking, FetchPickingResult_s, void **)
	ATTRIBUTE_METHOD (CBufferPicking, ClearPickingResult_s)
	ATTRIBUTE_METHOD (CBufferPicking, CheckDoPick_s)
	ATTRIBUTE_METHOD1 (CBufferPicking, GetPickLeftTop_s, Vector2 *)
	ATTRIBUTE_METHOD1 (CBufferPicking, SetPickLeftTop_s, Vector2)
	ATTRIBUTE_METHOD1 (CBufferPicking, GetPickWidthHeight_s, Vector2 *)
	ATTRIBUTE_METHOD1 (CBufferPicking, SetPickWidthHeight_s, Vector2)
	ATTRIBUTE_METHOD1 (CBufferPicking, IsResultDirty_s, bool *)
	ATTRIBUTE_METHOD1 (CBufferPicking, SetResultDirty_s, bool)
	ATTRIBUTE_METHOD1 (CBufferPicking, GetPickIndex_s, int *)
	ATTRIBUTE_METHOD1 (CBufferPicking, SetPickIndex_s, int)
	ATTRIBUTE_METHOD1 (CBufferPicking, GetViewport_s, int *)
	ATTRIBUTE_METHOD1 (CBufferPicking, SetViewport_s, int)
virtual HRESULT	InitDeviceObjects ()
virtual HRESULT	DeleteDeviceObjects ()
DWORD	Pick (int nX, int nY, int nViewportId=-1)
	pick by a point in the viewport. More...
int	Pick (const QRect &region, int nViewportId=-1)
	pick in a rectangular region in the viewport to retrieve the actually result, use GetPickingResult(), which returns an array of unique picking id. More...
const vector< DWORD > &	GetPickingResult ()
	return an array of unique picking id in the last pick call. More...
int	GetPickingCount ()
	return the number of objects picked. More...
DWORD	GetPickingID (int nIndex=0)
	get the picked item id of the given picking item. More...
void	FetchPickingResult (DWORD **ppResult)
void	ClearPickingResult ()
	clear last picking result
void	SetPickLeftTop (const Vector2 &vPos)
const Vector2 &	GetPickLeftTop ()
void	SetPickWidthHeight (const Vector2 &vPos)
const Vector2 &	GetPickWidthHeight ()
int	GetPickIndex () const
void	SetPickIndex (int val)
bool	IsResultDirty () const
void	SetResultDirty (bool bDirty=true)
int	GetViewport () const
void	SetViewport (int val)
void	CheckDoPick (bool bForceUpdate=false)
	do picking using current picking rectangle. More...
Public Member Functions inherited from ParaEngine::AssetEntity
	AssetEntity (const AssetKey &key)
	ATTRIBUTE_DEFINE_CLASS (AssetEntity)
	ATTRIBUTE_METHOD1 (AssetEntity, GetLocalFileName_s, const char **)
	ATTRIBUTE_METHOD1 (AssetEntity, SetLocalFileName_s, const char *)
	ATTRIBUTE_METHOD1 (AssetEntity, GetRemoteAssetURL_s, const char **)
	ATTRIBUTE_METHOD1 (AssetEntity, IsValid_s, bool *)
	ATTRIBUTE_METHOD1 (AssetEntity, IsLoaded_s, bool *)
	ATTRIBUTE_METHOD1 (AssetEntity, IsLocked_s, bool *)
	ATTRIBUTE_METHOD1 (AssetEntity, IsInitialized_s, bool *)
	ATTRIBUTE_METHOD1 (AssetEntity, GetState_s, int *)
	ATTRIBUTE_METHOD1 (AssetEntity, SetState_s, int)
virtual AssetType	GetType ()
virtual const std::string &	GetIdentifier ()
virtual bool	AutoSync (bool bForceSync=false, bool bLazyLoading=true)
	call this function to automatically sync with the remote server according to current asset state More...
virtual void	Refresh (const char *sFilename=NULL, bool bLazyLoad=false)
	refresh the asset from local disk. More...
virtual const string &	GetLocalFileName ()
	the actual local file name. More...
virtual void	SetLocalFileName (const char *sFileName)
virtual string	GetRemoteAssetURL ()
	get the remote server url of this asset. More...
virtual CParameterBlock *	GetParamBlock (bool bCreateIfNotExist=false)
	get effect parameter block with this object. More...
bool	IsValid ()
	whether this is a valid resource object. More...
bool	IsInitialized ()
	whether initialized. More...
virtual bool	IsLoaded ()
	most assets are loaded asynchronously. More...
virtual int	Release ()
	call this function to safely release this asset. More...
AssetKey &	GetKey ()
	return the key object. More...
AssetState	GetState ()
	return the asset state. More...
void	SetState (AssetState state)
	set the asset state. More...
virtual IAttributeFields *	GetAttributeObject ()
	get the attribute object of this asset. More...
virtual HRESULT	RestoreDeviceObjects ()
virtual HRESULT	InvalidateDeviceObjects ()
virtual HRESULT	RendererRecreated ()
	callback of listening the event that renderer was recreated on Android/WP8 all opengl related id has already become invalid at this time, no need to release them, just recreate them all in this function.
virtual void	Cleanup ()
	Clean up additional resources. More...
void	LoadAsset ()
	load asset. More...
void	UnloadAsset ()
	unload asset. More...
void	GarbageCollectMe ()
	if its reference count is zero, unload this asset object. More...
bool	IsLocked ()
	whether this is a locked resource resource. More...
virtual bool	Lock (int nMethod=0)
	Lock the object. More...
virtual void	UnLock ()
	UnLock the object.
virtual bool	GetBoundingBox (Vector3 *pMin, Vector3 *pMax)
	Get AABB bounding box of the asset object. More...
Public Member Functions inherited from ParaEngine::IAttributeFields
virtual int	GetAttributeClassID ()
	attribute class ID should be identical, unless one knows how overriding rules work. More...
virtual const char *	GetAttributeClassName ()
	a static string, describing the attribute class object's name
virtual const char *	GetAttributeClassDescription ()
	a static string, describing the attribute class object
	ATTRIBUTE_METHOD1 (IAttributeFields, GetName_s, const char **)
	ATTRIBUTE_METHOD1 (IAttributeFields, SetName_s, const char *)
	ATTRIBUTE_METHOD (IAttributeFields, PrintObject_s)
	ATTRIBUTE_METHOD (IAttributeFields, AddRef_s)
	ATTRIBUTE_METHOD1 (IAttributeFields, GetRefCount_s, int *)
	ATTRIBUTE_METHOD1 (IAttributeFields, SetTime_s, int)
	ATTRIBUTE_METHOD1 (IAttributeFields, GetTime_s, int *)
	ATTRIBUTE_METHOD (IAttributeFields, Release_s)
virtual void	SetIdentifier (const std::string &sID)
virtual bool	IsModified ()
	whether some of the fields are modified.It is up to the implementation class to provide this functionality if necessary. More...
virtual void	SetModified (bool bModified)
	set whether any field has been modified. More...
virtual bool	ValidateFields ()
	validate all fields and return true if validation passed. More...
virtual string	GetValidationMessage ()
	get the recent validation message due to the most recent call to ValidateFields()
virtual bool	ResetField (int nFieldID)
	Reset the field to its initial or default value. More...
virtual bool	InvokeEditor (int nFieldID, const std::string &sParameters)
	Invoke an (external) editor for a given field. More...
virtual bool	AddChildAttributeObject (IAttributeFields *pChild, int nRowIndex=-1, int nColumnIndex=0)
	add child object. More...
virtual void *	QueryObjectByName (const std::string &sObjectType)
	convert to object of a given type. More...
virtual void *	QueryObject (int nObjectType)
	convert to object of a given type. More...
virtual int	GetTime ()
	get the current local time in case it is animated in milli seconds frames. More...
virtual void	SetTime (int nTime)
virtual CDynamicAttributeField *	GetDynamicField (const std::string &sName)
	Get a dynamic field with a given name. More...
virtual CDynamicAttributeField *	GetDynamicField (int nIndex)
	Get a dynamic field with a given index. More...
virtual const char *	GetDynamicFieldNameByIndex (int nIndex)
	get field name by index
virtual int	GetDynamicFieldCount ()
	how many dynamic field this object currently have. More...
virtual int	SetDynamicField (const std::string &sName, const CVariable &value)
	set a dynamic field with a given name. More...
virtual int	AddDynamicField (const std::string &sName, ATTRIBUTE_FIELDTYPE dwType)
	add dynamic field and return field index
virtual void	RemoveAllDynamicFields ()
	remove all dynamic fields
virtual int	SaveDynamicFieldsToString (std::string &output)
	save only text dynamic fields to fieldname = value text strings. More...
virtual int	LoadDynamicFieldsFromString (const std::string &input)
	load only text dynamic fields from string More...
CAttributeClass *	GetAttributeClass ()
	get the main attribute class object. More...
void	PrintObject ()
	print the content of this object to a text file at temp/doc/[ClassName].txt. More...
Public Member Functions inherited from ParaEngine::IObject
virtual void	Clone (IObject *obj) const
	Clone the object's contains to a pointer. More...
virtual IObject *	Clone () const
	Clone the object's contains and return a pointer to the newly created object. More...
virtual bool	Equals (const IObject *obj) const
	Compare the object with another object. More...
virtual const IType *	GetType () const
virtual std::string	ToString () const
WeakPtr_type &	GetWeakReference ()
	get weak reference object. More...
virtual int	ProcessObjectEvent (const ObjectEvent &event)
	this function is only used to backward compatibility of ParaObject:AddEvent() function. More...
Public Member Functions inherited from ParaEngine::CRefCounted
void	addref () const
	add reference count of the object. More...
bool	delref () const
	decrease reference count of the object. More...
int	GetRefCount () const
	get the reference count
CRefCounted *	AddToAutoReleasePool ()
	addref and releases the ownership sometime soon automatically (usually at the end of the current frame). More...

Protected Member Functions
bool	BeginBuffer ()
void	DrawObjects ()
void	EndBuffer ()
virtual CRenderTarget *	CreateGetRenderTarget (bool bCreateIfNotExist=true)
	a render target will be created with the same name as this object. More...
Protected Member Functions inherited from ParaEngine::IAttributeFields
virtual CAttributeClass *	CreateAttributeClass ()
	initialize fields
virtual CDynamicAttributesSet *	GetDynamicAttributes (bool bCreateIfNotExist=false)

Additional Inherited Members
Public Types inherited from ParaEngine::AssetEntity
enum	AssetState {   ASSET_STATE_NORMAL, ASSET_STATE_LOCAL, ASSET_STATE_REMOTE, ASSET_STATE_CACHE,   ASSET_STATE_SYNC_START, ASSET_STATE_SYNC_SUCCEED, ASSET_STATE_SYNC_FAIL, ASSET_STATE_FAILED_TO_LOAD }
	the asset state. More...
enum	AssetType {   base =0, texture, mesh, multianimation,   spritevertex, font, sound, mdx,   parax, database, effectfile, dllplugin,   datagrid, cadMesh, image }
	each asset type has a unique asset type number
Public Types inherited from ParaEngine::IAttributeFields
typedef ParaEngine::weak_ptr< IObject, IAttributeFields >	WeakPtr_type
Public Types inherited from ParaEngine::IObject
typedef ParaEngine::weak_ptr< IObject >	WeakPtr_type
Static Public Member Functions inherited from ParaEngine::AssetEntity
static const string &	GetAssetServerUrl ()
	get the asset server url. More...
static void	SetAssetServerUrl (const char *pStr)
	set the asset server url. More...
Static Public Member Functions inherited from ParaEngine::IAttributeFields
static HRESULT	GetAttributeClassID_s (IAttributeFields *cls, int *p1)
static HRESULT	GetAttributeClassName_s (IAttributeFields *cls, const char **p1)
static bool	OpenWithDefaultEditor (const char *sFilename, bool bWaitOnReturn=false)
	Open a given file with the default registered editor in the game engine. More...
Public Attributes inherited from ParaEngine::AssetEntity
AssetKey	m_key
	this is the unique key object. More...
bool	m_bIsInitialized
	whether this entity is initialized;Entity is by default lazily initialized
bool	m_bIsValid
	whether this is a valid resource object. More...
Protected Attributes inherited from ParaEngine::IObject
WeakPtr_type	m_weak_reference
Protected Attributes inherited from ParaEngine::CRefCounted
int	m_refcount

Detailed Description

picking from frame buffer (back buffer) When there is picking query, it will render scene again (if out dated) with a special shader and read pixels from the back buffer.

We can query a single point or we can query a rectangle region in the current viewport and see if have hit anything. Please note: in order for buffer picking to work, each pickable object/component should assign a different picking id in its draw method. In other words, picking and drawing are done using the same draw function.

Member Function Documentation

CheckDoPick()

void ParaEngine::CBufferPicking::CheckDoPick

(

bool

bForceUpdate = false

)

do picking using current picking rectangle.

One do not need to call this manually, this function is called automatically when querying the picking result with GetPickingID and GetPickingCount.

Parameters

bForceUpdate

: if true, we will force update. if false, we will only do picking when result is dirty.

CreateGetRenderTarget()

CRenderTarget * ParaEngine::CBufferPicking::CreateGetRenderTarget ( bool  bCreateIfNotExist = true )

protectedvirtual

a render target will be created with the same name as this object.

FetchPickingResult()

void ParaEngine::CBufferPicking::FetchPickingResult

(

DWORD **

ppResult

)

Parameters

ppResult

the caller needs to ensure that ppResult is at least GetPickingCount() big. Otherwise it will crash

GetChildAttributeColumnCount()

int ParaEngine::CBufferPicking::GetChildAttributeColumnCount ( )

virtual

we support multi-dimensional child object.

by default objects have only one column.

Reimplemented from ParaEngine::IAttributeFields.

GetChildAttributeObject()

IAttributeFields * ParaEngine::CBufferPicking::GetChildAttributeObject ( const std::string &  sName )

virtual

get attribute by child object.

used to iterate across the attribute field hierarchy.

Reimplemented from ParaEngine::IAttributeFields.

GetChildAttributeObjectCount()

int ParaEngine::CBufferPicking::GetChildAttributeObjectCount ( int  nColumnIndex = 0 )

virtual

get the number of child objects (row count) in the given column.

please note different columns can have different row count.

Reimplemented from ParaEngine::IAttributeFields.

GetPickingCount()

int ParaEngine::CBufferPicking::GetPickingCount

(

)

return the number of objects picked.

GetPickingID()

DWORD ParaEngine::CBufferPicking::GetPickingID

(

int

nIndex = 0

)

get the picked item id of the given picking item.

if no data at the index return 0.

Parameters

nIndex

if -1, it will use m_currentPickIndex;

GetPickingResult()

const vector<DWORD>& ParaEngine::CBufferPicking::GetPickingResult ( )

inline

return an array of unique picking id in the last pick call.

InstallFields()

int ParaEngine::CBufferPicking::InstallFields ( CAttributeClass *  pClass, bool  bOverride  )

virtual

this class should be implemented if one wants to add new attribute.

This function is always called internally.

Reimplemented from ParaEngine::AssetEntity.

Pick() [1/2]

DWORD ParaEngine::CBufferPicking::Pick	(	int	nX,
		int	nY,
		int	nViewportId = -1
	)

pick by a point in the viewport.

Tip: to pick a thin line, one may consider picking by a small rect region.

Parameters

nViewportId

viewport index, if -1 it means the current viewport.

Returns

the picking data directly. if 0 means nothing is picked.

Pick() [2/2]

int ParaEngine::CBufferPicking::Pick	(	const QRect &	region,
		int	nViewportId = -1
	)

pick in a rectangular region in the viewport to retrieve the actually result, use GetPickingResult(), which returns an array of unique picking id.

Parameters

nViewportId

viewport index, if -1 it means the current viewport.

Returns

the number of pixels in region that has hit something pickable.

---

The documentation for this struct was generated from the following files:

• Client/trunk/ParaEngineClient/3dengine/BufferPicking.h
• Client/trunk/ParaEngineClient/3dengine/BufferPicking.cpp