#include <NIS_Drawer.hxx>

Inheritance diagram for NIS_Drawer:

Public Types
enum	DrawType { Draw_Normal = 0, Draw_Top = 1, Draw_Transparent = 2, Draw_Hilighted = 3, Draw_DynHilighted = 4 }

Public Member Functions
	NIS_Drawer ()

virtual	~NIS_Drawer ()

NIS_InteractiveContext *	GetContext () const

virtual void	Assign (const Handle< NIS_Drawer > &theOther)

virtual const Bnd_B3f &	GetBox (const NIS_View *pView=0L) const

void	SetUpdated (const DrawType theType) const

void	SetUpdated (const DrawType theType1, const DrawType theType2) const

void	SetUpdated (const DrawType theType1, const DrawType theType2, const DrawType theType3) const

void	SetUpdated (const DrawType theType1, const DrawType theType2, const DrawType theType3, const DrawType theType4) const

void	SetDynamicHilighted (const Standard_Boolean isHilighted, const Handle< NIS_InteractiveObject > &theObj, const Handle< NIS_View > &theView=0L)

virtual Standard_Integer	HashCode (const Standard_Integer theN) const

virtual Standard_Boolean	IsEqual (const Handle< NIS_Drawer > &theOth) const

TColStd_MapIteratorOfPackedMapOfInteger	ObjectIterator () const

NCollection_List< NIS_DrawList * >	GetLists () const

Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor. More...

	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing. More...

Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter. More...

virtual	~Standard_Transient ()
	Destructor must be virtual. More...

virtual void	Delete () const
	Memory deallocator for transient classes. More...

virtual const Handle_Standard_Type &	DynamicType () const
	Returns a type information object about this object. More...

Standard_Boolean	IsInstance (const Handle_Standard_Type &theType) const
	Returns a true value if this is an instance of Type. More...

Standard_Boolean	IsInstance (const Standard_CString theTypeName) const
	Returns a true value if this is an instance of TypeName. More...

Standard_Boolean	IsKind (const Handle_Standard_Type &theType) const
	Returns true if this is an instance of Type or an instance of any class that inherits from Type. Note that multiple inheritance is not supported by OCCT RTTI mechanism. More...

Standard_Boolean	IsKind (const Standard_CString theTypeName) const
	Returns true if this is an instance of TypeName or an instance of any class that inherits from TypeName. Note that multiple inheritance is not supported by OCCT RTTI mechanism. More...

virtual Handle_Standard_Transient	This () const
	Returns a Handle which references this object. Must never be called to objects created in stack. More...

Standard_Integer	GetRefCount () const
	Get the reference counter of this object. More...

Protected Member Functions
void	UpdateExListId (const Handle< NIS_View > &theView) const

virtual void	BeforeDraw (const DrawType theType, const NIS_DrawList &theDrawList)

virtual void	AfterDraw (const DrawType theType, const NIS_DrawList &theDrawList)

virtual void	Draw (const Handle< NIS_InteractiveObject > &, const DrawType theType, const NIS_DrawList &theDrawList)=0

virtual void	redraw (const DrawType theType, const Handle< NIS_View > &theView)

void	addObject (const NIS_InteractiveObject *theObj, const Standard_Boolean isShareList, const Standard_Boolean isUpVws)

void	removeObject (const NIS_InteractiveObject *theObj, const Standard_Boolean isUpVws)

virtual NIS_DrawList *	createDefaultList (const Handle< NIS_View > &) const

Standard_Integer	NObjects () const
	Get the number of interactive objects in this drawer. More...

Protected Attributes
NCollection_List< NIS_DrawList * >	myLists

Standard_ShortReal	myTransparency

Standard_Integer	myIniId
	ID of the initializing InteractiveObject. It is never changed, can be used to compute hash code of the Drawer instance. More...

Standard_Integer	myObjPerDrawer
	Maximal range of IDs of objects in one drawer. Limits the size of draw lists. Can be initialized only in constructor (default 1024). It is strictly prohibited to change this value outside the constructor. More...

Detailed Description

Abstract Drawer type. Drawer provides the immediate OpenGL drawing for every NIS_InteractiveObject maneged by the given Drawer instance. Each Drawer instance has reciprocal link with a number of NIS_InteractiveObject instances of the same (corresponding to Drawer) type. The idea is to group the drawing for all referred interactive objects using the same pre- and post-treatment like color setting, matrix, polygon offset, line thickness and what not.

<> Visual properties of Drawer

Normally visual properties of any NIS_InteractiveObject are stored in its Drawer instance, but not in an object. For example, if an interactive object has method SetColor() then the color is stored in the corresponding Drawer rather than in the interactive object itself. This scheme avoid useless duplication when a lot of objects have similar properties like color. Please see

See Also: nis_interactiveobject_drawer to learn how this mechanism works from the side of NIS_InteractiveObject.

<> Drawing

There are 3 virtual methods to implement OpenGL drawing in this API. They define the drawing cycle that consists of filling the internal OpenGL draw list with commands. This drawing cycle is triggered when the corresponding internal instance of NIS_DrawList has 'IsUpdated' flag (you can set this flag by means of public methods NIS_Drawer::SetUpdated()).

BeforeDraw() : contains all OpenGL commands that define the common set of visual properties for all managed interactive objects. This method is called once in the beginning of drawing cycle for the Drawer instance
Draw() : all OpenGL commands that are specific to a given interactive object, usually definition of vertices, triangles, lines, or their arrays.
AfterDraw() : commands that revert the status of OpenGL context to the state before execution of BeforeDraw(). This method is called once in the end of drawing cycle.

Each of these methods receives NIS_DrawList and DrawType, both identify the OpenGL draw list that should be filled with commands. Based on DrawType you will be able to define different presentation - the most important case is how hilighted (selected) interactive object is presented.

For advanced purposes you also can redefine the virtual method redraw(), it is dedicated to higher-level management of draw lists and ordering of their update when necessary.

<> Distinction of Drawer instances

Every Drawer should define which interactive objects it may manage and which - may not. The same idea could be shaped alternatively: every interactive object should understand to what Drawer it can attach itself. This question is answerd by special virtual method IsEqual() that compares two Drawers of the same type. Two instances of Drawer are equal if they have the same set of visual properties that are implemented in BeforeDraw(). The method IsEqual() is the core of Drawer architecture and it must be implemented very carefully for any new type. Particularly, for any derived class the method IsEqual() should first call the same method of its superclass.

For the optimal efficiency of OpenGL drawing it is better to keep the size of draw list (i.e., the number of interactive objects in a Drawer instance) not too small and not too big. The latter limitation is entered by the protected field myObjPerDrawer. It is used in method IsEqual() of the base Drawer class: two Drawers are not equal if they are initialized on objects that have too different IDs – even if all visual properties of these two Drawer instances coincide.

<> Cloning Drawer instances

It is possible to clone a Drawer instance with the viryual method Assign(). This method copies all visual properties and other important data from the Drawer provided as parameter. Method Clone() also should be very carefully implemented for any new Drawer type, to make sure that all necessary data fields and structures are properly copied.

Member Enumeration Documentation

enum NIS_Drawer::DrawType

Enumerator
Draw_Normal
Draw_Top
Draw_Transparent
Draw_Hilighted
Draw_DynHilighted

Constructor & Destructor Documentation

NIS_Drawer::NIS_Drawer ( )

inline

Empty constructor.

virtual NIS_Drawer::~NIS_Drawer ( )

virtual

Destructor.

Member Function Documentation

void NIS_Drawer::addObject	(	const NIS_InteractiveObject *	theObj,
		const Standard_Boolean	isShareList,
		const Standard_Boolean	isUpVws
	)

protected

virtual void NIS_Drawer::AfterDraw	(	const DrawType	theType,
		const NIS_DrawList &	theDrawList
	)

protectedvirtual

Called after execution of Draw(), once per group of interactive objects.

Reimplemented in NIS_SurfaceDrawer, and NIS_TriangulatedDrawer.

virtual void NIS_Drawer::Assign ( const Handle< NIS_Drawer > & theOther )

virtual

Copy the relevant information from another instance of Drawer. raises exception if theOther has incompatible type (test IsKind).

Reimplemented in NIS_SurfaceDrawer, and NIS_TriangulatedDrawer.

virtual void NIS_Drawer::BeforeDraw	(	const DrawType	theType,
		const NIS_DrawList &	theDrawList
	)

protectedvirtual

Called before execution of Draw(), once per group of interactive objects.

Reimplemented in NIS_SurfaceDrawer, and NIS_TriangulatedDrawer.

virtual NIS_DrawList* NIS_Drawer::createDefaultList ( const Handle< NIS_View > & ) const

protectedvirtual

virtual void NIS_Drawer::Draw	(	const Handle< NIS_InteractiveObject > &	,
		const DrawType	theType,
		const NIS_DrawList &	theDrawList
	)

protectedpure virtual

Main function: display the given interactive object in the given view.

Implemented in NIS_SurfaceDrawer, and NIS_TriangulatedDrawer.

virtual const Bnd_B3f& NIS_Drawer::GetBox ( const NIS_View * pView = 0L ) const

virtual

Create a3D bounding box of drawn objects.

Parameters

pView In not NULL, only objects visible in this view are taken.

NIS_InteractiveContext* NIS_Drawer::GetContext ( ) const

inline

Query the Interactive Context.

NCollection_List<NIS_DrawList *> NIS_Drawer::GetLists ( ) const

inline

Query associated draw lists.

virtual Standard_Integer NIS_Drawer::HashCode ( const Standard_Integer theN ) const

virtual

Hash value, for Map interface.

virtual Standard_Boolean NIS_Drawer::IsEqual ( const Handle< NIS_Drawer > & theOth ) const

virtual

Matching two instances, for Map interface.

Reimplemented in NIS_SurfaceDrawer, and NIS_TriangulatedDrawer.

Standard_Integer NIS_Drawer::NObjects ( ) const

inlineprotected

Get the number of interactive objects in this drawer.

TColStd_MapIteratorOfPackedMapOfInteger NIS_Drawer::ObjectIterator ( ) const

inline

Obtain the iterator of IDs of associated objects.

virtual void NIS_Drawer::redraw	(	const DrawType	theType,
		const Handle< NIS_View > &	theView
	)

protectedvirtual

Reimplemented in NIS_SurfaceDrawer.

void NIS_Drawer::removeObject	(	const NIS_InteractiveObject *	theObj,
		const Standard_Boolean	isUpVws
	)

protected

void NIS_Drawer::SetDynamicHilighted	(	const Standard_Boolean	isHilighted,
		const Handle< NIS_InteractiveObject > &	theObj,
		const Handle< NIS_View > &	theView = `0L`
	)

Switch on/off the dynamic hilight of the given object in the given view.

Parameters

isHilighted	True if the object should be hilighted, False - if not hilighted
theObj	Object instance that should be hilighted or unhilighted.
theView	View where the status of object must be changed. If NULL, the object is hilighted/unhilighted in all views.

void NIS_Drawer::SetUpdated ( const DrawType theType ) const

Mark all draw lists for update

void NIS_Drawer::SetUpdated	(	const DrawType	theType1,
		const DrawType	theType2
	)		const

void NIS_Drawer::SetUpdated	(	const DrawType	theType1,
		const DrawType	theType2,
		const DrawType	theType3
	)		const

void NIS_Drawer::SetUpdated	(	const DrawType	theType1,
		const DrawType	theType2,
		const DrawType	theType3,
		const DrawType	theType4
	)		const

void NIS_Drawer::UpdateExListId ( const Handle< NIS_View > & theView ) const

protected

Called to add draw list IDs to ex-list Ids of view. These draw lists are eventually released in the callback function, before anything is displayed

Field Documentation

Standard_Integer NIS_Drawer::myIniId

protected

ID of the initializing InteractiveObject. It is never changed, can be used to compute hash code of the Drawer instance.

NCollection_List<NIS_DrawList*> NIS_Drawer::myLists

protected

Standard_Integer NIS_Drawer::myObjPerDrawer

protected

Maximal range of IDs of objects in one drawer. Limits the size of draw lists. Can be initialized only in constructor (default 1024). It is strictly prohibited to change this value outside the constructor.

Standard_ShortReal NIS_Drawer::myTransparency

protected

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

NIS_Drawer.hxx

NIS_Drawer Class Referenceabstract

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation