CN105740060B - A kind of information filtering method in distributed virtual environment - Google Patents

Abstract

The invention belongs to field of information processing, and in particular to the information filtering method in a kind of distributed virtual environment.Specific steps are as follows: creation defines M announcement entity, N number of subscribing entities and a message screening module, definition system end of run time and propulsion step-length, all to announce motion information of the entity to message screening module statement update area and the region, all subscribing entities are stated to order the motion information in region and the region to message screening module；Message screening module will update, order area information is deposited respectively into UList or SList queue；Then entity or subscribing entities are announced and update its regional movement information to message screening module；Each update area and each intersection situation for ordering region are calculated, obtains the storage of region overlapping time intervals into ROTList；With time stepping method, announces entity and update it with renewal time stamp LVT_mAttribute A_mWhen, message screening module receives the subscribing entities list of the attribute value by determining according to the region overlapping time in ROTList, and removes the outdated information in ROTList.

Description

A kind of information filtering method in distributed virtual environment

Technical field

The invention belongs to field of information processing, and in particular to the information filtering method in a kind of distributed virtual environment.

Background technique

Distributed virtual environment (Distributed Virtual Environment, DVE) is based on virtual environment and net One technology of network.It on the one hand, include multiple pseudo-entities in DVE, each pseudo-entity has state alone, for describing it The attributes such as position, speed, acceleration.The world that these pseudo-entities generate for the computer that user provides immersion.Another party Face, the computer for running these pseudo-entities is connected by distributed network, and shared information.The use of diverse geographic location Family can be interacted on the network of interconnection in real time by controlling pseudo-entity.Due to passing through network communication between each pseudo-entity Message is sent and received, when pseudo-entity quantity is more, interaction is frequent or interaction data packet is larger, network communication load increases therewith Greatly, become an important factor for influencing the requirement of DVE system real time and operational efficiency.The message that pseudo-entity is sent and received into Row filtering can effectively reduce the transmission and processing of data packet, reduce network communication expense.

Generally, message screening mechanism makes entity only receive relative number as far as possible for filtering unrelated data According to.Two class pseudo-entities are usually defined in Virtual Space: announcing entity and subscribing entities.Wherein, announcing entity can be to it Its entity sends message；Subscribing entities can receive message from other entities.Entity and subscribing entities are announced respectively using update Region and order its interested region of region description.Update area and order region are defined in abstract d dimension space Coordinate subset.Update area defines the influence area for announcing entity, orders region and then describes the interested region of subscribing entities. It announces and orders both sides' exchange area and define information, announce entity according to local update region and the external matching knot for ordering region Fruit is to determine whether need to be sent out locally generated state update message.Subscribing entities only need to receive update area and this The state that other entities of region overlapping are ordered on ground updates.Therefore, message screening process needs to send and receive process for message Overlapping region list is provided, to determine which receiving entity message transmission each time has.

Message screening process include update area and order region statement, Region Matching calculates, overlapping region list makes With three steps.Firstly, multiple pseudo-entities state entity to message screening module as needed in initialization or when operation Update area and order region, the statement in region is the basis that Region Matching calculates, and needs the storage of corresponding data structure The update area of each pseudo-entity statement and order region.Secondly, message screening process searches and orders what region collection intersected Update area collection carries out Region Matching calculating, obtains overlapping region list.On the one hand, each update area and order region There is it that can generate the time range of effect, and since region may change at runtime, therefore, it is necessary to region Temporal information and motion information are described, it is also desirable to reduce the calculating of Region Matching calculating as far as possible according to these situations of change Expense.On the other hand, occur since entity changes update area or orders region in discrete time step, Region Matching calculates It carries out being also more natural method in discrete time step.However, this, which may cause event, loses problem: actually occurring Intersection process is not captured to, and is not sent and received in the suitable time so as to cause message.Finally, announcing entity hair It send and associated subscribing entities is sent the data to according to overlapping region list when message.

Therefore, the information filtering method in distributed virtual environment and region statement, Region Matching computing cost and region Computational accuracy is related.Message is sent and received process and is directly affected the number transmitted on a distribution network using information filtering method According to amount, have become a key technical problem of distributed virtual environment researcher care.Many researchers are in this side Many research work have been done in face, such as force matching message screening, the message screening based on grid etc..These methods can part Network data transmission is reduced, but accurate message screening can not be carried out, it is possible to create event loses problem.

Summary of the invention

The technical problem to be solved by the present invention is providing the information filtering method in a kind of distributed virtual environment, meet To the filtering requirement of interaction data between pseudo-entity in operational process, the data volume in transmission over networks is reduced.By accurate It calculates interworking entity and participates in the time interval of interaction, reduce the data processing operation of recipient, improve the utilization of computing resource Rate.Specific technical solution is as follows:

A kind of information filtering method in distributed virtual environment, comprising the following steps:

(1) creation defines M announcement entity, N number of subscribing entities, 1 message screening module, and in distributed virtual environment In to announce entity, subscribing entities and message screening module initialize, initial time t is set_cur=0, the end of run time For t_end, runing time step-length is timestep；Wherein M, N are natural number and meet M >=1, N >=1；The unit of timestep can When thinking, the chronomeres such as minute, second；

Announce entity P_mIt indicates, subscript m is to announce the unique identification of entity, m=1,2,3 ..., M；Subscribing entities S_n It indicates, subscript n is the unique identification of subscribing entities, n=1,2,3 ..., N；D dimension space relevant to pseudo-entity is defined, wherein D is natural number and meets D >=1.Each announcement entity P_mIt is corresponding with attribute variable's collection, uses A_mIt indicates,A_mIn t moment Value be A_m=A_m(t), each announcement entity P_mIt all include a local virtual time LVT_mIt is pushed away for recording local zone time Into LVT_mFor positive real number；Each subscribing entities S_nAll remember comprising a local virtual time for recording local time stepping method For LVT_n+M, LVT_n+MFor positive real number；

Announce entity P_mThere is the update area in D dimension space to be associated in any t moment, uses RU_m(t) it indicates (when indicating When certain specific moment or time range, RU can also be abbreviated as_m), RU_m(t)={ [Ul_m,d(t),Uu_m,d(t)], 1≤d≤D }, wherein Ul_m,d(t)、Uu_m,dIt (t) is real number, d is integer, respectively indicate the update area in the lower limit value and upper limit value of t moment d dimension, And meet Ul_m,d(t)≤Uu_m,d(t)；Update area RU_mIn UT_m=[Uta_m,Utb_m] in time range the movement of d dimension make With polynomial function RUFunc_m,d=Uv_m,d·t₁+0.5·Ua_m,d·t₁ ²It describes, wherein UT_m=[Uta_m,Utb_m] it is when updating Between section, Uv_m,dFor movement velocity, Ua_m,dFor acceleration, Uv_m,d、Ua_m,d、t₁、Uta_m、Utb_mFor real number and Uta_m≤t₁≤ Utb_m, define binary group RUMoveInfo_m,d=(Uv_m,d,Ua_m,d) store variable in the function.

Subscribing entities S_nThere is the order region in D dimension space to be associated in any t moment, uses RS_n(t) it indicates (when indicating When certain specific moment or time range, RS can also be abbreviated as_n), RS_n(t)={ [Sl_n,d(t),Su_n,d(t)], 1≤d≤D }, wherein Sl_n,d(t)、Su_n,d(t) it is real number, respectively indicates the order region in the lower limit value and upper limit value of t moment d dimension, and meet Sl_n,d(t)≤Su_n,d(t)；Order region RS_nIn ST_n=[Sta_n,Stb_n] in time range the movement of d dimension use it is multinomial Formula function RSFunc_n,d=Sv_n,d(Sta_n)·t₂+0.5·Sa_n,d·t₂ ²It describes, wherein ST_n=[Sta_n,Stb_n] it is when ordering Between section, Sv_n,d(Sta_n) it is Sta_nThe movement velocity at moment, Sa_n,dFor acceleration constant, Sv_n,d(Sta_n)、Sa_n,d、Sta_n、 Stb_nAnd t₂It is real number and Sta_n≤t₂≤Stb_n, define binary group RSMoveInfo_n,d=(Sv_n,d(Sta_n),Sa_n,d) storage Parameter in the function.

Message screening module indicates that it is the announcement of M that message screening module, which has a length, with MF (Message Filter) The order area queue SList that area queue UList and a length are N.UList m content UList_mIt is real to announce Body P_mAttribute update area four-tuple (UT_m,RU_m(Uta_m),RUMoveInfo_m,ROTList_m), wherein 1≤m≤M, ROTList_mIndicate that length is the queue of N, nth elements ROT in queue_m,n=(Tl_m,n,Tu_m,n), Tl_m,n、Tu_m,nAttach most importance to respectively The lower limit value and upper limit value of folded time interval, both for the real number for being more than or equal to 0；

RUMoveInfo_m={ RUMoveInfo_m,1,RUMoveInfo_m,2,...,RUMoveInfo_m,d,..., RUMoveInfo_m,DBe the update area motion information；

SList n-th content SList_nFor subscribing entities S_nOrder zone triplet (ST_n,RS_n(Sta_n), RSMoveInfo_n), wherein 1≤n≤N,

RSMoveInfo_m={ RSMoveInfo_m,1,RSMoveInfo_m,2,...,RSMoveInfo_m,d,..., RSMoveInfo_m,DBe the order region motion information；

The major function of message screening module is to utilize the update area and its motion information and SList stored in UList The order region of middle storage and its motion information are to region at the appointed time range UT_m∩ST_n=[max (Uta_m,Sta_n),min (Utb_m,Stb_n)] in the time interval that overlaps each other predicted, to obtain announcing entity P_mUpdate area RU_mWith order Entity S_nOrder region RS_nThe time interval ROT of overlapping_m,n；Due to two region RU_mAnd RS_nOverlapping each other meansThat is,D=1,2,3 ..., D.

The detailed process of initialization:

Announce entity P_m(m=1,2,3 ..., M) carry out initialization step are as follows: it enables and announces entity local virtual time LVT_m =0；Init attributes variables set A_m=A_m(0), renewal time section UT_m, update area RU in D dimension space_m(Uta_m) and its Motion information RUMoveInfo_m, wherein Uta_mIndicate moment value, RU_m(t) it indicates to announce entity P_mHave in D dimension space in t moment Update area be associated；M, D are natural number；A_m(0) value at the t=0 moment is indicated, initial time takes Uta_m=0；

Subscribing entities S_n(n=1,2,3 ..., N) carry out initialization step are as follows: enable the subscribing entities local virtual time LVT_n+M=0；Initialize order time section ST_n, order region RS in D dimension space_n(Sta_n) and its motion information RSMoveInfo_n, wherein Sta_nIndicate moment value, RS_n(t) subscribing entities S is indicated_nThere is the order area in D dimension space in t moment Domain is associated；N is natural number, and initial time takes Sta_n=0；

Message screening module initialization step are as follows: the announcement area queue UList and a length that one length of setting is M For the order area queue SList of N；When initialization, UList, SList are disposed as empty queue；

(2) motion information of the entity to message screening module statement update area and update area is announced for described M, it is described N number of subscribing entities are stated to order region and order the motion information in region to message screening module；Message screening module will update Region and its motion information, which are stored in, to be announced in area queue UList, will order region and its motion information is stored in and orders area In domain queue SList；Detailed process are as follows:

Announce entity P_mBy update area RU_m(Uta_m) and motion information RUMoveInfo_mWith time interval UT_mIt is sent to and disappears Cease filtering module；Message screening module updates m UList in UList queue_m, UList is set_m=(UT_m,RU_m(Uta_m), RUMoveInfo_m,ROTList_m), wherein ROTList_mFor the empty queue of length N；

Subscribing entities S_nRegion RS will be ordered_n(Sta_n) and order motion information RSMoveInfo_nWith time interval ST_nIt sends To message screening module；Message screening module updates n-th SList in SList queue_n:

SList is set_n=(ST_n,RS_n(Sta_n),RSMoveInfo_n), ULi queue each single item UList is set_m(m=1, 2,3 ..., M) in every ROT_m,nFor sky, ROT_m,nIt is ROTList_mN-th of queue.

(3) message screening module calculates the overlapping time model of subscribing entities ordered region and announce entity update area It encloses, and updates corresponding overlapping time intervals ROT value in UList list；

(31) each single item UList in UList queue is traversed_mIn ROTList_m(m=1,2,3 ..., M), if ROTList_m It is not sky, thens follow the steps (32)；Otherwise, step (33) are executed；

(32) UList is traversed_mMiddle ROTList_mEvery ROT_m,n(n=1,2,3 ..., N), if ROT_m,nFor sky, then it is directed to Announce entity P_mWith subscribing entities S_n, respectively from UList_mAnd SList_nMiddle acquisition update area and order region and update area Motion information and order region motion information, execute step (34)；Otherwise, movement is not executed, (4) are entered step；

(33) for announcement entity P_m, traverse each subscribing entities S_n(n=1,2,3 ..., N), respectively from UList_mWith SList_nThe middle motion information for obtaining update area and ordering region and update area and the motion information for ordering region, execute Step (34)；

(34) equation according to the following formula,

Wherein t_curFor real number, to execute the current time when step, Uu_m,d(t_cur)、Ul_m,d(t_cur)、Uv_m,d(t_cur)、 Su_n,d(t_cur)、Sl_n,d(t_cur) and Sv_n,d(t_cur) it is respectively current t_curThe Uu at moment_m,d、Ul_m,d、Uv_m,d, and max (Uta_m, Sta_n)≤t_cur≤min(Utb_m,Stb_n)；

Solve the range of the disaggregation t of inequality, as ROT_m,n；UList is set_mThe ROTList of element_mN-th in queue Entry value is ROT_m,n；

(4) it announces entity and sends attribute to subscribing entities according to the overlapping time intervals obtained in step (3)；

(41) entity P is announced_mThe process of (1≤m≤M) Update attribute: if judgement t_curNot equal to 0 and A_m(t_cur) it is equal to A_m (t_cur- timestep), then the corresponding attribute variable's collection of the entity is not updated；Otherwise, step (42) are gone to；

(42) entity P is announced_mCurrent time LVT is sent to message screening module_m, request acquisition [LVT_m,LVT_m+ Timestep] time range and P_mThe subscribing entities list of domain of the existence overlapping；

(43) message screening module initializes an empty list EntityList, for storing the order for receiving more new data Entity；

(44) message screening module inquiry m elements of UList list obtain ROTList_mList；

(45) according to LVT_mUpdate ROTList_mEvery ROT in list_m,n, n=1,2,3 ..., N be allowed to as the newest time, And determine the subscribing entities needed from entity reception message is announced, the specific steps are as follows:

(451) remember ROT_m,n=(c, e), judges LVT_mWhether+timestep is more than or equal to c, if it is, going to step (452)；Otherwise end step (45)；

(452) judge LVT_mWhether it is greater than e, if it is, going to step (453), otherwise, updates ROT_m,nValue is ROT_m,n =[LVT_m, e], and by subscribing entities S_nEntityList list is added；

(453)ROT_m,nIt is worth out of date, enables ROT_m,n=(null, null)；

(46) entity P is announced_mEntityList list is obtained from message screening module, if the list length is expressed as X, Middle X is integer and 0≤X≤N；

(47) entity P is announced_mEach subscribing entities S into EntityList list_x, x=1,2,3 ..., X, which is sent, to be belonged to Property A_mValue and its timestamp LVT_m, subscribing entities S_nReceive attribute data A_mIt is handled afterwards, each subscribing entities S_nProcessing The process of data receiver is as follows:

(471) judge local zone time LVT_n+MWhether LVT is more than or equal to_m, if so, the data are out-of-date, disregard, tie Beam step (47)；If it is not, local zone time is then advanced to LVT_mMoment, and make LVT_n+M=LVT_m；

(472) enter attribute A_mReception process flow, i.e., the value is stored or is applied to the reality of subscribing entities In the operation of border.

(5) time stepping method enables t_cur=t_cur+timestep；If meeting t_cur> t_end, then end processing；Otherwise, under One step；

(6) it announces entity and updates local virtual time and Update attribute value；Subscribing entities update the local virtual time；

Detailed process are as follows: announce entity P_mUpdate attribute A_m=A_m(t_cur) and local virtual time LVT_m=t_cur(m=1, 2,3 ..., M), subscribing entities S_nUpdate local virtual time LVT_n+M=t_cur(n=1,2,3 ..., N)；A_m(t_cur) value with Specific application is related, can determine at random in some applications, is determined in some applications according to certain conditions.For example, certain In the distributed virtual environment of unmanned plane collision detection, on the one hand the attribute of the position and speed of unmanned plane is updated according to unmanned plane Being executed for task determines, on the other hand needs to adjust the movement velocity of itself according to the motion profile of other unmanned planes.

(7) it announces entity and subscribing entities is respectively modified update area and orders area information, return step (2)；Specifically Process are as follows:

(71) entity P is announced_mThe process that (1≤m≤M) modifies update area is as follows:

Judge Utb_mWhether t is greater than_cur, if so, the announcement entity does not modify update area, go to step (73)；If It is no, then execute (72)；

(72) renewal time section UT is modified_m, and modify the update area RU of every d dimension in D dimension space_m,dAnd binary group RUMoveInfo_m,d；

(73) certain subscribing entities S_nThe process that region is ordered in (n=1 ..., N) modification is as follows:

Judge Stb_nWhether t is greater than_cur, if so, the subscribing entities, which are not modified, orders region, execute step (75)；If It is no, then execute (74)；

(74) order time section ST is modified_n, and modify the order region RS of every d dimension in D dimension space_n,dAnd binary group RSMoveInfo_n,d；

(75) return step (2)；

It can reach following using the present invention the utility model has the advantages that the present invention is asked for the message screening in distributed virtual environment Topic not only solves and carries out the problem of data filtering reduces network transmission, and by being overlapped matched side based on region space-time Method accurately estimates and carries out the period that data are filtered, improving the precision of data filtering.The present invention pseudo-entity more New region or order region accurately calculate region overlapping time when changing, and not only can be reduced the number of region overlapping calculation, It is allowed to without being calculated in each time step, and the region overlapping occurred between adjacent time step-length, solution can be captured Certainly event loses problem.

Detailed description of the invention

Fig. 1 is overview flow chart of the present invention；

Fig. 2 is the flow chart of all announcement entities and subscribing entities statement area information；

Fig. 3 is the flow chart of MF module zoning overlapping time intervals；

Fig. 4 is the flow chart announced entity and send attribute to subscribing entities.

Specific embodiment

In order to better understand the content of the present invention, it is illustrated with reference to the accompanying drawings and examples.

As shown in Figure 1, treatment process of the invention are as follows: M announcement entity of creation definition, N number of subscribing entities and one disappear Filtering module is ceased, M announcement entity, N number of subscribing entities and the message screening module are initialized simultaneously, define system operation End time t_end, promote step-length timestep.Then all announcements entities to message screening module state it initially during this The motion information of update area and the region, all subscribing entities state its initial order region and the area to message screening module The motion information in domain；Message screening module deposits update area, order area information respectively to corresponding UList or SList team In column；Then entity or subscribing entities are announced and update its regional movement information to message screening module；Then message screening module Each update area and each intersection situation for ordering region are calculated according to update and order region and its motion information, is calculated To region overlapping time intervals store into corresponding ROTList；Finally, during carrying out time stepping method, when announcement entity P_mIt updates it and stabs LVT with renewal time_mAttribute A_mWhen, message screening module will be according to ROTList_mIn region overlapping when Between determination can receive the subscribing entities list of the attribute value, while removing ROTList_mIn outdated information for updating ROTList_m。

Assuming that there is an announcement entity P in the example₁, a subscribing entities S₁With a message screening module MF, when operation Between be t_end=3s, time stepping method step-length are timestep=1s.P₁Attribute and update area information modification and S₁Order Area information is modified as shown in table 1~3:

1 attribute change table of table

2 update area information of table modifies table

Table 3 orders region and modifies table

Specific step is as follows for embodiment:

Step 1: defining two-dimensional space (D=2) relevant to pseudo-entity, the dimension of hyperspace is initialized；When initial Between t_cur=0；Initialize 1 announcement entity, 1 subscribing entities and a MF module.

1.1: initial message filtering module MF:

The empty queue UList that length is 1 is set；The empty queue SList that length is 1 is set.

Entity and 1 subscribing entities are announced for 1.2:1 to be initialized in the client of distribution operation.

Entity P is announced in initialization₁Are as follows: enable LVT₁=0；Init attributes are A₁=A₁(0)=10, renewal time, section was UT₁=[Uta₁,Utb₁]=[0,1] s；Update area is the rectangle of 1m × 1m in 2 dimension spaces, is expressed as RU₁(0)={ [Ul_1,1 (0),Uu_1,1(0)],[Ul_1,2(0),Uu_1,2(0)] }={ [6,7], [4,5] }, the region are initial in renewal time interval range Movement velocity is Uv_1,1(0)=- 2m/s, Uv_1,2(0)=2m/s, acceleration Ua_1,1=0, Ua_1,2=0m/s²。

Initialize subscribing entities S₁Are as follows: enable LVT₂=0；Initialization order time section is ST₁=[Sta₁,Stb₁]=[0, 3] s orders the rectangle that region is 1m × 1m in 2 dimension spaces, is expressed as RS₁(0)={ [Sl_1,1(0),Su_1,1(0)],[Sl_1,2 (0),Su_1,2(0)] }={ [3,4], [5,6] }；Region initial motion speed in order time interval range is Sv_1,1(0) =2m/s, Sv_1,2(0)=- 2m/s, acceleration Sa_1,1=0, Sa_1,2=8m/s²。

Step 2: 1 announcement entity and 1 subscribing entities to MF module statement update area and order area information.Such as Shown in Fig. 2, for the flow chart of all announcement entities and subscribing entities statement area information.

Announce entity P₁State the process of update area are as follows:

2.1:P₁By update area RU₁(0) and its motion information

RUMoveInfo₁={ (Uv_1,1(0),Ua_1,1),(Uv_1,2(0),,Ua_1,2) and time interval UT₁It is sent to MF mould Block.

2.2:MF module updates the 1st UList in UList queue₁Content:

Initialize queue ROTL₁UList is arranged in the empty queue for being 1 for length₁For UList₁=(UT₁,RU₁(0), RUMoveInfo₁,ROTList₁)。

Subscribing entities S₁The process in region is ordered in statement are as follows:

2.3:S₁Region RS will be ordered₁(0) and its motion information

RSMoveInfo₁={ (Sv_1,1(0),Sa_1,1),(Sv_1,2(0),Sa_1,2) and time interval ST₁It is sent to MF module.

2.4:MF module updates the 1st SList in SList queue₁:

SList is set₁=(ST₁,RS₁(0),RSMoveInfo₁)。

UList is arranged in 2.5:MF module₁In ROT_1,1For sky.

Step 3: MF module calculates the overlapping time of subscribing entities ordered region and announce entity update area, and more Corresponding ROT value in new UList list；As shown in figure 3, the flow chart of MF module zoning overlapping time.

3.1: traversal UList queue obtains non-empty queue UList₁；

3.2: traversal UList₁Middle ROTList₁List obtains ROT_1,1, due to ROT_1,1For sky, it is therefore desirable to calculate the area ROT Domain overlapping time, then for announcement entity P₁With subscribing entities S₁, respectively from UList₁And SList₁It is middle obtain corresponding region and Its motion information；

3.3: ROT is obtained according to the disaggregation that equation (1) solves inequality_1,1, UList is set₁The ROTList of element₁Queue In the 1st entry value be ROT_1,1；

3.3.1: enable ROT_1,1=(- ∞ ,+∞), [a, b]=[Uta₁,Utb₁]∩[Sta₁,Stb₁]=[0,1] ∩ [0,3] =[0,1], a, b are the intermediate variable for assignment.

3.3.2: for d=1, i.e. the first dimension of 2 dimension spaces calculates RU_1,1、RS_1,1In the dimension in [a, b] time range Overlapping time IntervalSet¹: IntervalSet¹=[0.5,1].

3.3.3: for d=2, i.e. the second dimension of 2 dimension spaces calculates RU_1,2、RS_1,2In the dimension in [a, b] time range Overlapping time IntervalSet²: IntervalSet²=[0,0.5].

3.3.4: solving

ROT_1,1=ROT_1,1∩IntervalSet¹∩IntervalSet²=(- ∞ ,+∞) ∩ [0.5,1] ∩ [0,0.5] =[0.5,0.5], i.e., region RU in two-dimensional space₁And RS₁Only intersect at the t=0.5s moment in time [0,1] range.Due to t =0.5s the moment occurs between two step-length points of t=0 and t=1, if only each step-length point calculate in real time update area and The intersection situation for ordering region will be unable to the region that capture occurs in t=0.5 and intersect information.By in t=0 according to area Domain motion conditions accurately calculate the following potential establishment domain matched period, improve the precision of Region Matching, solve to get over Part loses problem.

3.3.5: setting UList₁The ROTList of element₁The 1st entry value in queue is ROT_1,1

Step 4: announcing result that entity is calculated according to overlapping time intervals to subscribing entities Update attribute, detailed process As shown in Figure 4.

4.1: t at this time_curEqual to 0, then 4.2 are executed；

4.2:P₁Current time LVT is sent to MF module₁=0, and request to obtain in [LVT₁,LVT₁+ timestep]= [0,1] the subscribing entities list of generation area overlapping therewith in s time range；

The 1st UList of 4.3:MF module polls UList list₁Obtain ROTList₁List, ROTList₁Element in list ROT_1,1=[c, e]=[0.5,0.5]；

4.4: according to LVT₁=0 updates ROTList₁ROT in list_1,1For the newest time and determine ordering for reception attribute update Purchase entity:

4.4.1: according to LVT₁Calculate LVT₁+ tiemstep meets LVT₁+ tiemstep=1 > c=0.5；

4.4.2: judge LVT₁=0 < e=0.5, then update ROT_1,1Value is ROT_1,1=[max (LVT₁, c), e]=[max (0,0.5), 0.5]=[0.5,0.5], i.e. order region is in LVT₁=0.5 moment and announcement entity update area RU₁Intersection, will Subscribing entities S₁EntityList list is added；

4.5: announcing entity P₁EntityList list is obtained from MF module；

4.6: because including subscribing entities S in EntityList list₁, therefore announce entity P₁To S₁Send attribute A₁=10 And its timestamp LVT₁, S₁Receive A₁It is handled afterwards:

4.6.1: judging local zone time LVT₂With LVT₁Relationship, LVT₂=LVT₁=0, then go to 4.6.2；

4.6.2: entering attribute A₀Reception process flow.By attribute A₀Stored or be applied to the reality of subscribing entities In the operation of border.The reception process flow is related to specific application, for example, in the distributed virtual ring of certain unmanned plane collision detection In border, each unmanned plane all has subscribed the position and speed attribute of other unmanned planes, the attribute for receiving other unmanned planes more After new, unmanned plane will adjust the motion profile of itself based on collision detection algorithm.

Step 5: carrying out time stepping method.Time stepping method is to subsequent time, t at this time_cur=t_cur+ timestep=0+1= 1s meets t_cur< t_end；

Step 6: all announcement entities and subscribing entities carry out time stepping method；Announce entity P₁The local virtual time be LVT₁=1, Update attribute A₁=A₁(1)=5.Subscribing entities S₁Local virtual time LVT₂=1.

Step 7: announcement entity and subscribing entities are respectively modified update area and order area information.

For announcing entity P₁, execute following procedure:

7.1: due to Utb₁=t_cur, then 7.2 are executed；

7.2: modifying renewal time section according to table 2 is UT₁=[Uta₁,Utb₁]=[1,3] s, acceleration Ua_1,1=0, Ua_1,2=1m/s²；At this point, update area is still the rectangle of 1m × 1m, current time position is RU₁(1)={ [Ul_1,1(1),Uu_1,1 (1)],[Ul_1,2(1),Uu_1,2(1)] }={ [4,5], [6,7] }；The movement velocity at current time is Uv_1,1(1)=- 2m/s, Uv_1,2(1)=2m/s.Specific modification and application are related, in the present embodiment, announcement entity attributes update reference table 1 into Row, the modification of update area information and the modification content of reference table 2 and table 3 progress respectively for ordering area information.

For subscribing entities S₁, execute following procedure:

7.3: due to Stb_n< t_cur, then the subscribing entities, which are not modified, orders region, terminates 7.3.

Step 8: announcing entity P₁Update area is stated again to MF module.

8.1:P₁By update area RU₁(1) and its motion information RUMoveInfo₁={ (Uv_1,1(1),Ua_1,1),(Uv_1,2 (1),Ua_1,2) and time binary group UT₁It is sent to MF module.

8.2:MF module updates the 1st UList in UList queue₁Content: initialization ROTList₁The sky for being 1 for length UList is arranged in queue₁=(UT₁,RU₁,RUMoveInfo₁,ROTList₁)。

Step 9: MF module calculates the overlapping time of subscribing entities ordered region and announce entity update area, and more Corresponding ROT value in new UList list.

9.1: traversal UList queue obtains non-empty queue UList₁；

9.2: traversal UList₁Middle ROTList₁List, due to ROT_1,1For sky, it is therefore desirable to calculate ROT overlapping time, then For announcement entity P₁With subscribing entities S₁, respectively from UList₁And SList₁It is middle to obtain corresponding region and its motion information；

9.3: ROT is obtained according to the disaggregation that equation (1) solves inequality_1,1, UList is set₁The ROTList of element₁Queue In the 1st entry value be ROT_1,1。

9.3.1: enable ROT_1,1=(- ∞ ,+∞), [a, b]=[Uta₁,Utb₁]∩[Sta₁,Stb₁]=[1,3] ∩ [0,3] =[1,3].As it can be seen that it is update area and order region within the scope of [1,3] s that the ROT value currently calculated, which embodies time interval, Intersect situation, if each region and its motion conditions do not change (in this example when t=2) during this period, without recalculating The intersection in the two regions, to reduce the number of region overlapping calculation.

9.3.2: for d=1, i.e. the first dimension of 2 dimension spaces calculates RU_1,1、RS_1,1In the dimension in [a, b] time range Overlapping time IntervalSet¹: IntervalSet¹=[1,1].

9.3.3: for d=2, i.e. the second dimension of 2 dimension spaces calculates RU_1,2、RS_1,2In the dimension in [a, b] time range Overlapping time IntervalSet²:

9.3.4: solving Region RU i.e. in two-dimensional space₁And RS₁It is non-intersecting in time [1,3] range.

Step 10: announcing entity P₁According to overlapping time to subscribing entities Update attribute.

10.1: A at this time₁(t_cur) it is not equal to A₁(t_cur- timestep), then execute 9.2；

10.2:P₁Current time LVT is sent to MF module₁=1, and request the subscribing entities column of generation area overlapping therewith Table；

10.3:MF module initialization EntityList list；

The 1st UList of 10.4:MF module polls UList list₁Obtain ROTList₁List；

10.5: according to LVT₁Update ROTList₁Every ROT in list_1,1For the newest time and determine what reception attribute updated Subscribing entities:

Therefore terminate the 10.5th step, EntityList list is still empty；

10.6: announcing entity P₁EntityList list is obtained from MF module；

10.7: announcing entity P₁Into EntityList list, each subscribing entities sends attribute A_mValue and its timestamp LVT₁, because list is empty by EntityList, announce entity P₁Without to any subscribing entities Update attribute, attribute more new data quilt Filtering.It can be seen that can carry out data filtering by this method reduces network transmission.

Step 11: carrying out time stepping method.

11.1: time stepping method to subsequent time, at this time t_cur=t_cur+ timestep=1+1=2s meets t_cur< t_end；

11.2: all announcement entities and subscribing entities carry out time stepping method；

11.2.1: announce entity P₁The local virtual time be LVT₁=2, Update attribute A₁=A₁(2)=6.

11.2.2: subscribing entities S₁Local virtual time LVT₂=2.

Step 12: announcement entity and subscribing entities are respectively modified update area and order area information.

For announcing entity P₁, execute following procedure:

12.1: due to Utb₁> t_cur, then the announcement entity does not modify update area and goes to the 12nd step；

For subscribing entities S₁, execute following procedure:

12.2: due to Stb_n< t_cur, then the subscribing entities, which are not modified, orders region, terminates 6.2.

Step 13: announcing entity according to overlapping time to subscribing entities Update attribute.

13.1: A at this time₁(t_cur) it is not equal to A₁(t_cur- timestep), then execute 13.2；

13.2:P₁Current time LVT is sent to MF module₁=2, and request the subscribing entities column of generation area overlapping therewith Table；

13.3:MF module initialization EntityList list；

The 1st UList of 13.4:MF module polls UList list₁Obtain ROTList₁List, ROTList₁Element in list

13.5: according to LVT₁Update ROTList₁Every ROT in list_1,1For the newest time and determine what reception attribute updated Subscribing entities:

13.5.1:Therefore terminate the 13.5th step, EntityList list is still empty；

13.6: announcing entity P₁EntityList list is obtained from MF module；

13.7: announcing entity P₁Into EntityList list, each subscribing entities sends attribute A₁(2) value and its time Stab LVT₁, because not including subscribing entities in EntityList list, therefore announce entity P₁It does not send and belongs to any subscribing entities Property, attribute more new data is filtered.

Step 14: carrying out time stepping method.

14.1: time stepping method to subsequent time, at this time t_cur=t_cur+ timestep=2+1=3s meets t≤t_end；

14.2: all announcement entities and subscribing entities carry out time stepping method；

14.2.1: announce entity P₁The local virtual time be LVT₁=3, Update attribute A₁=A₁(3)=7；

14.2.2: subscribing entities S₁Local virtual time LVT₂=3.

Step 15: announcement entity and subscribing entities are respectively modified update area and order area information.

For announcing entity P₁, execute following procedure:

15.1: due to Utb₁=t_end, then the announcement entity does not modify update area, goes to the 16th step；

For subscribing entities S₁, execute following procedure:

15.2: due to Stb_n=t_end, then the subscribing entities, which are not modified, orders region, terminates 15.2.

Step 16: announcing entity according to overlapping time to subscribing entities Update attribute.

16.1: A at this time₁(t_cur) it is not equal to A₁(t_cur- timestep), then execute 16.2；

16.2:P₁Current time LVT is sent to MF module₁=3, and request the subscribing entities column of generation area overlapping therewith Table；

16.3:MF module initialization EntityList list；

The 1st UList of 16.4:MF module polls UList list₁Obtain ROTList₁List, ROTList₁Element in list

16.5: according to LVT₁Update ROTList₁Every ROT in list_1,1For the newest time and determine what reception attribute updated Subscribing entities:

16.5.1:Therefore terminate the 16.5th step, EntityList list is still empty；

16.6: announcing entity P₁EntityList list is obtained from MF module；

16.7: announcing entity P₁Into EntityList list, each subscribing entities sends attribute A₁(3) value and its time Stab LVT₁, because not including subscribing entities in EntityList list, therefore announce entity P₁It does not send and belongs to any subscribing entities Property, attribute more new data is filtered.

Step 17: carrying out time stepping method.

17.1: time stepping method to subsequent time, at this time t_cur=t_cur+ timestep=3+1=4s meets t_cur> t_en。

Step 18: reaching terminates service condition, terminate operation.

It should be pointed out that those skilled in the art can be in claim the invention is not limited to specific embodiments above Protection scope in make any deformation or improvement, be within the scope of the present invention.

Claims (6)

1. the information filtering method in a kind of distributed virtual environment, which comprises the following steps:

(1) creation defines M announcement entity, N number of subscribing entities, 1 message screening module, and right in distributed virtual environment It announces entity, subscribing entities and message screening module to be initialized, initial time t is set_cur=0, the end of run time is t_end, runing time step-length is timestep, and wherein M, N are natural number and meet M >=1, N >=1；

Announce entity P_mIt indicates, subscript m is to announce the unique identification of entity, m=1,2,3 ..., M；Subscribing entities S_nIt indicates, Subscript n is the unique identification of subscribing entities, n=1,2,3 ..., N；D dimension space relevant to pseudo-entity is defined, wherein D is certainly It so counts and meets D >=1；Each announcement entity P_mIt is corresponding with attribute variable's collection, uses A_mIt indicates,A_mIn the value of t moment For A_m=A_m(t), each announcement entity P_mIt all include a local virtual time LVT_mFor recording local time stepping method, LVT_mFor Positive real number；Each subscribing entities S_nAll LVT is denoted as recording local time stepping method comprising a local virtual time_n+M, LVT_n+MFor positive real number；

Announce entity P_m(m=1,2,3 ..., M) carry out initialization step are as follows: it enables and announces entity local virtual time LVT_m=0； Init attributes variables set A_m=A_m(0), renewal time section UT_m, update area RU in D dimension space_m(Uta_m) and its movement Information RUMoveInfo_m, wherein Uta_mIndicate moment value, RU_m(t) it indicates to announce entity P_mHave in D dimension space more in t moment New region is associated；M, D are natural number；A_m(0) value at the t=0 moment is indicated, initial time takes Uta_m=0；When update Between section be expressed as UT_m=[Uta_m,Utb_m], Uta_m、Utb_mFor real number；

Subscribing entities S_n(n=1,2,3 ..., N) carry out initialization step are as follows: enable subscribing entities local virtual time LVT_n+M=0； Initialize order time section ST_n, order region RS in D dimension space_n(Sta_n) and its motion information RSMoveInfo_n, wherein Sta_nIndicate moment value, RS_n(t) subscribing entities S is indicated_nThere is the order region in D dimension space to be associated in t moment；N is certainly So number, initial time take Sta_n=0；Order time section is expressed as ST_n=[Sta_n,Stb_n], Sta_n、Stb_nIt is real number；

Message screening module initialization step are as follows: the announcement area queue UList and a length that one length of setting is M are N Order area queue SList；When initialization, UList, SList are disposed as empty queue；UList m content UList_m To announce entity P_mAttribute update area four-tuple (UT_m,RU_m(Uta_m),RUMoveInfo_m,ROTList_m), wherein 1≤m ≤ M, ROTList_mIndicate that length is the queue of N, nth elements ROT in queue_m,n=(Tl_m,n,Tu_m,n), Tl_m,n、Tu_m,nRespectively For the lower limit value and upper limit value of overlapping time intervals, both for the real number for being more than or equal to 0；

(2) motion information of the entity to message screening module statement update area and update area is announced for described M, it is described N number of Subscribing entities are stated to order region and order the motion information in region to message screening module；Message screening module is by update area It is stored in and is announced in area queue UList with its motion information, region and its motion information will be ordered and ordering area queue In SList；

(3) message screening module calculates the overlapping time range of subscribing entities ordered region and announce entity update area, and Update corresponding overlapping time intervals ROT value in UList list；

(4) it announces entity and sends attribute to subscribing entities according to the overlapping time intervals obtained in step (3)；

(5) time stepping method enables t_cur=t_cur+timestep；If meeting t_cur> t_end, then end processing；Otherwise, into next step Suddenly；

(6) it announces entity and updates local virtual time and Update attribute value；Subscribing entities update the local virtual time；

(7) it announces entity and subscribing entities is respectively modified update area and orders area information, return step (2).

2. the information filtering method in a kind of distributed virtual environment as described in claim 1, which is characterized in that the step (2) detailed process are as follows:

Announce entity P_mBy update area RU_m(Uta_m) and motion information RUMoveInfo_mWith renewal time section UT_mIt is sent to and disappears Cease filtering module；Message screening module updates m UList in UList queue_m, UList is set_m=(UT_m,RU_m(Uta_m), RUMoveInfo_m,ROTList_m), wherein ROTList_mFor the empty queue of length N；

Subscribing entities S_nRegion RS will be ordered_n(Sta_n) and motion information RSMoveInfo_nWith order time section ST_nIt is sent to and disappears Cease filtering module；Message screening module updates n-th SList in SList queue_n: i.e. setting SList_n=(ST_n,RS_n(Sta_n), RSMoveInfo_n), UList queue each single item UList is set_mEvery ROT in (m=1,2,3 ..., M)_m,nFor sky, ROT_m,nIt is ROTList_mN-th entry value of queue.

3. the information filtering method in a kind of distributed virtual environment as described in claim 1, which is characterized in that the step (3) the following steps are included:

(31) each single item UList in UList queue is traversed_mIn ROTList_m(m=1,2,3 ..., M), if ROTList_mIt is not Sky thens follow the steps (32)；Otherwise, step (33) are executed；

(32) UList is traversed_mMiddle ROTList_mEvery ROT_m,n(n=1,2,3 ..., N), if ROT_m,nFor sky, then it is directed to and announces Entity P_mWith subscribing entities S_n, respectively from UList_mAnd SList_nIt middle acquisition update area and orders region and update area and orders The motion information in region is purchased, is executed step (34)；Otherwise, (4) are entered step；

(33) for announcement entity P_m, traverse each subscribing entities S_n(n=1,2,3 ..., N), respectively from UList_mAnd SList_n The middle motion information for obtaining update area and ordering region and update area and the motion information for ordering region, execute step (34)；

(34) equation according to the following formula,

Wherein t_curFor real number, to execute the current time when step, Uu_m,d(t_cur)、Ul_m,d(t_cur)、Uv_m,d(t_cur)、Su_n,d (t_cur)、Sl_n,d(t_cur) and Sv_n,d(t_cur) it is respectively current t_curThe Uu at moment_m,d、Ul_m,d、Uv_m,d, and max (Uta_m,Sta_n)≤ t_cur≤min(Utb_m,Stb_n)；

Solve the range of the disaggregation t of inequality, as ROT_m,n；UList is set_mThe ROTList of element_mThe n-th entry value in queue For ROT_m,n。

4. the information filtering method in a kind of distributed virtual environment as described in claim 1, which is characterized in that the step (4) detailed process are as follows:

(41) entity P is announced_mThe process of (1≤m≤M) Update attribute: if judgement t_curNot equal to 0 and A_m(t_cur) it is equal to A_m(t_cur- Timestep), then the corresponding attribute variable's collection of the entity is not updated；Otherwise, step (42) are gone to；

(42) entity P is announced_mCurrent time LVT is sent to message screening module_m, request acquisition [LVT_m,LVT_m+ timestep] when Between range and P_mThe subscribing entities list of domain of the existence overlapping；

(43) message screening module initializes an empty list EntityList, for storing the order reality for receiving more new data Body；

(44) message screening module inquiry m elements of UList list obtain ROTList_mList；

(45) according to LVT_mUpdate ROTList_mEvery ROT in list_m,n, n=1,2,3 ..., N be allowed to as the newest time, and really It is fixed to need from the subscribing entities for announcing entity reception message, the specific steps are as follows:

(451) remember ROT_m,n=(c, e), judges LVT_mWhether+timestep is more than or equal to c, if it is, going to step (452)； Otherwise end step (45)；

(452) judge LVT_mWhether it is greater than e, if it is, going to step (453), otherwise, updates ROT_m,nValue is ROT_m,n= [LVT_m, e], and by subscribing entities S_nEntityList list is added；

(453)ROT_m,nIt is worth out of date, enables ROT_m,n=(null, null)；

(46) entity P is announced_mEntityList list is obtained from message screening module, if the list length is expressed as X, wherein X is Integer and 0≤X≤N；

(47) entity P is announced_mEach subscribing entities S into EntityList list_x, x=1,2,3 ..., X sends attribute A_m Value and its timestamp LVT_m, subscribing entities S_nReceive attribute data A_mIt is handled afterwards, each subscribing entities S_nHandle data Received process is as follows:

(471) judge local zone time LVT_n+MWhether LVT is more than or equal to_m, if so, the data are out-of-date, disregard, end step (47)；If it is not, local zone time is then advanced to LVT_mMoment, and make LVT_n+M=LVT_m；

(472) enter attribute A_mReception process flow, i.e., the value is stored or is applied to the practical operation of subscribing entities In.

5. the information filtering method in a kind of distributed virtual environment as described in claim 1, which is characterized in that the step (6) detailed process are as follows: announce entity P_mUpdate attribute A_m=A_m(t_cur) and local virtual time LVT_m=t_cur, m=1,2, 3 ..., M, subscribing entities S_nUpdate local virtual time LVT_n+M=t_cur, n=1,2,3 ..., N.

6. the information filtering method in a kind of distributed virtual environment as described in claim 1, which is characterized in that the step (7) detailed process are as follows:

Detailed process are as follows:

(71) entity P is announced_mThe process that (1≤m≤M) modifies update area is as follows:

Judge Utb_mWhether t is greater than_cur, if so, the announcement entity does not modify update area, go to step (73)；If it is not, then holding Row (72)；

(72) renewal time section UT is modified_m, and modify the update area RU of every d dimension in D dimension space_m,dAnd binary group RUMoveInfo_m,d；

(73) certain subscribing entities S_nThe process that region is ordered in (n=1 ..., N) modification is as follows:

Judge Stb_nWhether t is greater than_cur, if so, the subscribing entities, which are not modified, orders region, execute step (75)；If it is not, then holding Row (74)；

(74) order time section ST is modified_n, and modify the order region RS of every d dimension in D dimension space_n,dAnd binary group RSMoveInfo_n,d；

(75) return step (2).