SLEntities Class Reference

Scenegraph in Data Oriented Design with flat std::vector of SLEntity. More...

#include <SLEntities.h>

Public Member Functions
void	addChildEntity (SLint myParentID, SLEntity entity)
	Adds a child into the vector nodes right after its parent. More...
void	deleteEntity (SLint id)
	Deletes a node at index id with all its children. More...
void	deleteChildren (SLint id)
	Deletes all children of an entity with index id. More...
SLint	updateWMRec (SLint id, SLMat4f &parentWM)
	Updates all world matrices and returns no. of updated. More...
SLEntity *	getEntity (SLint id)
	Returns the pointer to a node if id is valid else a nullptr. More...
SLint	getEntityID (SLNode *node)
	Returns the ID of the entity with a SLNode pointer. More...
SLEntity *	getParent (SLint id)
	Returns the pointer to the parent of a node if id is valid else a nullptr. More...
SLint	getParentID (SLNode *node)
	Returns the parentID of a SLNode pointer. More...
void	dump (SLbool doTreeDump)
	Dump scenegraph as a flat vector or as a tree. More...
SLuint	size ()
	Returns the size of the entity vector. More...
void	clear ()
	Clears the the entities vector. More...

Private Attributes
SLVEntity	_graph
	Vector of SLEntity of entire scenegraph. More...

Detailed Description

Scenegraph in Data Oriented Design with flat std::vector of SLEntity.

Definition at line 46 of file SLEntities.h.

Member Function Documentation

addChildEntity()

void SLEntities::addChildEntity	(	SLint	myParentID,
		SLEntity	entity
	)

Adds a child into the vector nodes right after its parent.

addChild adds a child node by inserting an SLEntities into a vector in Depth First Search order. The root node gets the parent ID -1. The child is inserted right after the parent node.

Parameters

myParentID	Index of the parent node
entity	The entity to add as child of the parent

Definition at line 21 of file SLEntities.cpp.

{
    if (myParentID > (int)_graph.size() || myParentID < -1)
        SL_EXIT_MSG("Invalid parent ID");
 
    SLint entityID; // ID and insert position of new entity
 
#ifdef SL_USE_ENTITIES_DEBUG
    this->dump(true);
#endif
 
    if (_graph.empty())
    {
        // Root node and ignore myParentID
        entityID = 0;
        _graph.push_back(entity);
        _graph[0].parentID   = -1;
        _graph[0].childCount = 0;
        _graph[0].om         = _graph[0].node->om();
        _graph[0].node->entityID(0);
        if (_graph[0].node->parent() != nullptr)
            SL_EXIT_MSG("Root node parent pointer must be null");
    }
    else
    {
        entity.parentID   = myParentID;
        entity.childCount = 0;
        entity.om         = entity.node->om();
 
        // Loop forward to the insert position
        SLint insertPos = myParentID + 1;
        while (insertPos < _graph.size() && _graph[insertPos].parentID >= myParentID)
            insertPos++;
 
        entityID = insertPos;
        if (entityID == _graph.size())
            _graph.push_back(entity); // faster than insert
        else
            _graph.insert(_graph.begin() + entityID, entity);
 
        _graph[myParentID].childCount++;
 
        // Increase parentIDs of following subtrees that are greater
        for (SLuint i = entityID + 1; i < _graph.size(); i++)
            if (_graph[i].parentID > myParentID)
                _graph[i].parentID++;
 
        // Correct all node->entityIDs
        for (SLint i = 0; i < _graph.size(); ++i)
            _graph[i].node->entityID(i);
    }
 
    // Recursively add children of the entity
    if (_graph[entityID].node->children().size())
    {
        for (SLint i = 0; i < _graph[entityID].node->children().size(); ++i)
        {
            SLNode* childNode = _graph[entityID].node->children()[i];
            this->addChildEntity(entityID, SLEntity(childNode));
        }
    }
}

clear()

void SLEntities::clear ( )

inline

Clears the the entities vector.

Definition at line 80 of file SLEntities.h.

{ _graph.clear(); }

deleteChildren()

void SLEntities::deleteChildren

(

SLint

id

)

Deletes all children of an entity with index id.

Deletes all children of an entity with the index id. Also sub-children of those children get deleted.

Parameters

id	Index of the parent entity

Definition at line 277 of file SLEntities.cpp.

{
    assert(id <= _graph.size() &&
           id >= 0 &&
           "Invalid id");
 
    // Find the next child with the same parentID
    SLuint toID;
    SLint  myParentID = _graph[id].parentID;
    for (toID = id + 1; toID < _graph.size(); toID++)
        if (_graph[toID].parentID == myParentID)
            break;
 
    // Erase the elements in the vector
    _graph.erase(_graph.begin() + id + 1, _graph.begin() + toID);
    _graph[id].childCount = 0;
 
    // Decrease parentIDs of following subtrees that are greater
    SLuint numNodesToErase = toID - id;
    for (SLuint i = id; i < _graph.size(); i++)
        if (_graph[i].parentID > myParentID)
            _graph[i].parentID = _graph[i].parentID - numNodesToErase;
}

deleteEntity()

void SLEntities::deleteEntity

(

SLint

id

)

Deletes a node at index id with all its children.

Deletes a node at index id with all with all children

Parameters

id	Index of node to delete

Definition at line 244 of file SLEntities.cpp.

{
    assert(id <= _graph.size() &&
           id >= 0 &&
           "Invalid id");
 
    if (id == 0)
        _graph.clear();
    else
    {
        // Find the next child with the same parentID
        SLint toID;
        SLint myParentID = _graph[id].parentID;
        for (toID = id + 1; toID < _graph.size(); toID++)
            if (_graph[toID].parentID == myParentID)
                break;
 
        // Erase the elements in the vector
        _graph.erase(_graph.begin() + id, _graph.begin() + toID);
        _graph[myParentID].childCount--;
 
        // Decrease parentIDs of following subtrees that are greater
        SLint numNodesToErase = toID - id;
        for (SLuint i = id; i < _graph.size(); i++)
            if (_graph[i].parentID > myParentID)
                _graph[i].parentID = _graph[i].parentID - numNodesToErase;
    }
}

dump()

void SLEntities::dump

(

SLbool

doTreeDump

)

Dump scenegraph as a flat vector or as a tree.

Prints the scenegraph vector flat or as hierarchical tree as follows:

Parameters

doTreeDump

Flag if dump as a tree or flat

Pattern: ID.Parent.childCount Example from SLEntities::addChild: 00.-1.04 +–01.00.01 | +–02.01.00 +–03.00.00 +–04.00.02 | +–05.04.00 | +–06.04.01 | | +–07.06.01 | | | +–08.07.00 +–09.00.00

Definition at line 188 of file SLEntities.cpp.

{
    if (doTreeDump)
    {
        for (SLuint i = 0; i < _graph.size(); ++i)
        {
            // Calculate depth
            SLuint depth      = 0;
            SLint  myParentID = _graph[i].parentID;
            while (myParentID != -1)
            {
                depth++;
                myParentID = _graph[myParentID].parentID;
            }
 
            string tabs;
            for (int d = 1; d < (int)depth; ++d)
                tabs += "|  ";
            if (depth > 0)
                tabs += "+--";
            cout << tabs;
 
            SLstring nodeStr = _graph[i].node ? _graph[i].node->name() : "";
            printf("%02u(%02d).%02d.%02u-%s\n",
                   i,
                   _graph[i].node->entityID(),
                   _graph[i].parentID,
                   _graph[i].childCount,
                   nodeStr.c_str());
        }
        cout << endl;
    }
    else
    {
        for (SLuint i = 0; i < _graph.size(); ++i)
            printf("|  %02u  ", i);
        cout << "|" << endl;
 
        for (SLuint i = 0; i < _graph.size(); ++i)
            cout << "-------";
        cout << "-" << endl;
 
        for (SLuint i = 0; i < _graph.size(); ++i)
            if (_graph[i].parentID == -1)
                printf("|-1  %02u", _graph[i].childCount);
            else
                printf("|%02u  %02u", _graph[i].parentID, _graph[i].childCount);
        cout << "|" << endl;
    }
    cout << "----------------------------------------------------------" << endl;
}

getEntity()

SLEntity * SLEntities::getEntity

(

SLint

id

)

Returns the pointer to a node if id is valid else a nullptr.

Returns the pointer to the node at id

Parameters

id	The index of the node to return as a pointer

Returns

The pointer of the node at id

Definition at line 89 of file SLEntities.cpp.

{
    if (id >= 0 && id < _graph.size())
        return &_graph[id];
    else
        return nullptr;
}

getEntityID()

SLint SLEntities::getEntityID

(

SLNode *

node

)

Returns the ID of the entity with a SLNode pointer.

Returns the ID for the passed SLNode if found else INT32_MIN

Definition at line 99 of file SLEntities.cpp.

{
    for (SLint i = 0; i < _graph.size(); ++i)
        if (_graph[i].node == node)
            return i;
    return INT32_MIN;
}

getParent()

SLEntity * SLEntities::getParent

(

SLint

id

)

Returns the pointer to the parent of a node if id is valid else a nullptr.

Returns the pointer to the parent of the node at id

Parameters

id	The index of the node in the scenegraph vector

Returns

The pointer of the parent of the node at id

Definition at line 111 of file SLEntities.cpp.

{
    if (id >= 1 && id < _graph.size())
        return &_graph[_graph[id].parentID];
    else
        return nullptr;
}

getParentID()

SLint SLEntities::getParentID

(

SLNode *

node

)

Returns the parentID of a SLNode pointer.

Returns the parentID for the passed SLNode if found else INT32_MIN

Definition at line 121 of file SLEntities.cpp.

{
    for (SLEntity& entity : _graph)
        if (entity.node == node)
            return entity.parentID;
    return INT32_MIN;
}

size()

SLuint SLEntities::size ( )

inline

Returns the size of the entity vector.

Definition at line 77 of file SLEntities.h.

{ return (SLuint)_graph.size(); }

updateWMRec()

SLint SLEntities::updateWMRec	(	SLint	id,
		SLMat4f &	parentWM
	)

Updates all world matrices and returns no. of updated.

Updates the world matrix recursively

Parameters

id	Index of the current node to update
parentWM	World transform matrix of the parent

Returns

The no. of nodes updated

Definition at line 134 of file SLEntities.cpp.

{
    SLEntity* entity = getEntity(id);
 
#ifdef SL_USE_ENTITIES_DEBUG
    SLMat4f nodeOM = entity->node->om();
    if (!entity->om.isEqual(nodeOM))
    {
        string nodeName = "nodeOM: " + entity->node->name();
        entity->om.print("entityOM:");
        entity->node->om().print(nodeName.c_str());
        entity->om = entity->node->om();
    }
#endif
 
    entity->wm.setMatrix(parentWM * entity->om);
    entity->wmI.setMatrix(entity->wm.inverted());
 
#ifdef SL_USE_ENTITIES_DEBUG
    SLMat4f nodeWM = entity->node->updateAndGetWM();
    if (!entity->wm.isEqual(nodeWM))
    {
        string nodeName = "nodeWM: " + entity->node->name();
        entity->wm.print("entityWM:");
        nodeWM.print(nodeName.c_str());
    }
#endif
 
    SLuint handledChildren = 0;
    while (handledChildren < entity->childCount)
    {
        SLuint childID = id + handledChildren + 1;
        handledChildren += this->updateWMRec(childID, entity->wm);
    }
 
    return handledChildren + 1;
}

Member Data Documentation

_graph

SLVEntity SLEntities::_graph

private

Vector of SLEntity of entire scenegraph.

Definition at line 83 of file SLEntities.h.

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

• SLEntities.h
• SLEntities.cpp