JPH0452755A - State restoration system - Google Patents

Abstract

PURPOSE:To restore a desired state at a high speed regardless of the past time point to be restored by defining all data stored at a time point approximate to a designated restored state as a starting point and then restoring the state at the starting point with use of the differential data. CONSTITUTION:If the storing state of the differential data satisfies the prescribed conditions, all data to be edited and the differential data are stored in a changed data store means 3. A restoring procedure deciding means 5 decides a restoring procedure based on all data stored before or after the state to be restored to restore an editing subject to a prescribed past state with use of the differential data after the restoration is instructed by a man-machine interface 1. A restoring means 6 reads the changed data decided by the means 5 out of the means 3 and performs the restoration processing based on the decided procedure. Thus the past state to be edited can be restored at a high speed.

Description

[Detailed Description of the Invention] [Industrial Fields of Application] The present invention is applicable to programs and data such as character strings, documents, figures, images, sounds, etc. The present invention relates to a state restoration method for restoring the edited object to the state of the past =- time when editing is performed.

[Conventional technology] Conventionally, character strings or documents of programs and data, figures,
Systems that create images, audio, etc. are equipped with editing functions such as moving, inserting, deleting, and replacing.
Furthermore, a state restoration function called undo or the like for returning an editing object to a desired past state is limited. By making full use of these functions, it is possible to easily create a desired editing target.

An example of the configuration of a conventional state restoration method is shown in FIG.

In FIG. 7, the man-machine interface 30 is
It is an interface between the computer and the user, which is equipped with a display device such as a CRT and an input device such as a keyboard or pointing device, and it displays the current state of the editing target, that is, the current editing target. It holds data.

The difference data creation means 31 creates a difference between the pre-editing state and the post-editing state of the editing target every time editing is performed.

The difference data storage means 32 sequentially stores the difference data created by the difference data creation means 31.

The ff1 source means 33 is a man-machine interface, -s 30
When an instruction to restore the state is issued, the difference data is read from the difference data storage means 32, and processing is performed to restore the editing target to the instructed past state.

Next, the operation of the configuration shown in FIG. 7 will be explained. The initial state of the editing target currently being edited is rabAcdB.
efgCCCCCCChiDjklmnEJ. In this state, the man-machine interface 30 issues a delete command as the first command to delete "A" as shown in FIG. 8, and the second command deletes rBJ.
is deleted and the third command adds the string rCCCCCCJ
is deleted, the fourth command deletes rDJ, and the fifth
Suppose that "E" is deleted using the command. At this time, the difference data creation means 31 generates A, B, CCCCCC, D, respectively when the first to fifth commands are generated.
Generate differential data of E. These difference data are stored in the difference data storage means 32 together with the type of editing command and the position from the beginning of the edited character string.

If rEJ is deleted by the fifth command and an instruction is given from the man-machine interface 30 to restore the current state to the state five commands ago, the restoring means 33 first deletes the previous command, this In this case, insert the rEJ deleted by the fifth command into the predetermined position, then insert the rDJ deleted by the two previous commands, i.e. the fourth command, into the predetermined position, and similarly "
CCCCCCJ and rBJ are sequentially inserted into predetermined positions to restore the state of five commands ago, and then sent to the man-machine interface 30.

Through the above operations, the editing target can be restored to a desired past state.

[Problems to be Solved by the Invention] However, in the conventional state restoration method, since the method restores the current state in order based on differential data,
There has been a problem in that it takes time to restore to an older past state.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a state restoration method that can quickly restore the past state of an object to be edited.

[Means for Solving the Problems] In order to achieve the above object, the state restoration method of the present invention firstly restores the state based on differential data accumulated each time an editing target is changed. In the state restoration method performed,
If the storage state of the difference data satisfies predetermined conditions, all data to be edited and the difference data at that point are stored, and when state restoration is instructed, the data is stored before or after the state to be restored. The feature is that the editing target is restored to a specified predetermined past state using differential data from all the data that is being edited. In the state restoration method that restores the state, the difference data consists of first difference data created when the editing target is changed, and second difference data created by organizing a plurality of first difference data. When the accumulation state of the differential data satisfies the predetermined first condition, all the first differential data after the previous accumulation of the second differential data is organized to create the second differential data, and the second differential data is created. The second difference data is accumulated together with the first difference data created this time, and if the accumulation state of the first and/or second difference data satisfies the predetermined second condition, the current editing target is All data and first difference data are accumulated, and when state restoration is instructed, the first and/or second difference data are used to specify the editing target from all data accumulated before or after the state to be restored. It is characterized by restoring to a predetermined past state.

[Operations] According to the present invention, not only the difference data but also all the data to be edited are accumulated in some places in the difference data string. Therefore, the state to be edited can be restored using the difference data from all the data accumulated temporally close to the state to be restored, so the past state can be restored in order from the current state based on the difference data. Compared to conventional state restoration methods, state restoration can be performed faster.

[Example code] Examples will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of an embodiment of the state restoration method according to the present invention, in which 1 is a man-machine interface, 2 is a difference data (hereinafter referred to as d data) creation means, and 3
4 represents a modified data storage means, 4 represents a stored data determination means, 5 represents a restoration procedure determination means, and 6 represents a restoration means.

In FIG. 1, a man-machine interface 1 includes C
It is an interface unit between a computer and a user, which includes a display device such as an RT, and an input device such as a keyboard and a pointing device, and holds the current state of the editing target, that is, the current editing target data.

The d data creation means 2 creates d data by calculating the difference between the pre-edited state and the post-edited state of the editing target each time editing is performed, and also calculates the time required to restore the created d data. , that is, the restoration time is calculated. In the following explanation, for ease of understanding,
It is assumed that all movements, replacements, etc. are replaced by deletions and insertions to create differential data.

The modified data storage means 3 is constituted by a suitable storage means such as a RAM, a floppy disk, etc., and stores d data or all data to be edited (hereinafter referred to as "all data").

The storage data determining means 4 determines which changed data, d data or total data, is to be stored in the changed data storage means 3.

The restoration procedure determining means 5 is a man-machine interface 1
This is to determine the changed data and restoration procedure necessary to restore the specified state in the shortest time when restoration is instructed by the system.

The restoration means 6 reads the changed data determined by the restoration procedure determination means 5 from the changed data storage means 3, performs restoration processing according to the determined procedure, and restores the editing target to the specified state.

Next, the operation of the configuration shown in FIG. 1 will be explained in detail.

When some editing is performed on the editing object and a change occurs, the man-machine interface sends a signal indicating that a change has occurred to the stored data determining means 4 via the signal line (O). At the same time, all the data to be edited before and after the change are sent to the d data creation means 2 via the signal line (A).

As a result, the d data creation means 2 creates the d data that is the difference between before and after the edit target and the restoration time of the d data.

At this time, the stored data determining means 4 determines which of the d data and the total data is to be stored in the changed data storing means 3. There are three methods for determining this stored data.

The first method is to calculate the partial sum of the restoration times of the d data accumulated since the previous accumulation of all data, and if that value is greater than or equal to a preset threshold, all data and d data are accumulated. , otherwise, it is determined to store only d data, and specifically, the method is as follows.

As shown in FIG. 2, all data A is stored in the changed data storage means 3 at the time t-, which is the initial state.
d data d+ (restoration time △10) by editing at the time of j+
is created and stored, and similarly, d data da (restoration time △ta2) and da (restoration time △to) are created and stored by editing at the time of jp and ta,
Assume that editing is performed at time t4 and d data d4 (restoration time Δtd4) is created. At this time, the stored data determining means 4 transmits the currently created d
At the same time, the restoration time Δtaa of the data d, is taken in from the changed data storage means 3, and the d data d+, d2. The restoration time △ja++ △td2 + △t, 3 of d+= is taken in, and if the sum of the restoration times △tdl+Δt, p+Δtag+△ta4 is greater than or equal to the preset threshold T th , then all the changes after the time of t4 are taken. All data B and d data d4 are stored, otherwise d data d4 is stored. FIG. 2 shows a case where all data B and d data d4 are accumulated. According to this, the time required for restoration will not exceed T th regardless of the restoration time, so it is clear that state restoration can be performed faster than conventional state restoration methods, especially , especially when restoring to an older past state.

The second method calculates the partial sum of the amount of d data accumulated since the previous accumulation of all data, and if the value is greater than a preset amount of data, the total data and d
This is a method of accumulating data, and if not, accumulating d data. Specifically, taking the case shown in FIG. 2 as an example, when d data d4 is created at time t4, the accumulated data The determining means 4 takes in the d data d4 created this time, and also receives the d data d+ + accumulated since the previous accumulation of all data A from the changed data accumulation means 3.
d 21 d a is taken in, the sum of the data amounts is calculated, and if the value is greater than or equal to the preset threshold B t h, all the data after the change at the time of t4, the total B and d data amount 4 are calculated. , otherwise only d data amount 4 is stored. This method takes advantage of the fact that the restoration time is roughly proportional to the amount of differential data, and according to this, the amount of data used for one restoration will exceed 8th regardless of the restoration point. Therefore, it is clear that state restoration can be performed faster than conventional state restoration methods, especially when restoring to an older past state. Note that in the second method, it is clear that there is no need to find the restoration time for each d data.

The third method is to accumulate all data and d data a predetermined number of times since the previous accumulation of all data.
This is a method of accumulating data. In this method, the restoration time may be longer than in the first and second methods, but it is clear that the state can be restored in a shorter time compared to the conventional state restoration method.
The process of determining the stored data in the stored data determining means 4 is extremely simple.

It is possible to arbitrarily select which of the three methods described above to use for determining the accumulated data as required.

When the storage data determining means 4 determines the change data to be stored, it instructs the change data storage means 3 through the signal line (1) about the change data to be stored. As a result, the changed data storage means 3 takes in and stores the currently created d data via the signal line (A) when storage of d data is instructed, and when storage of all data is instructed. captures and stores all changed data via the signal line (A). Also, at this time, the modified data storage means 3 captures and stores the restoration time created by the d data creation means 2 as needed.

Thereafter, stored data is determined in the same manner.

Next, the data structure of the changed data storage means 3 will be explained. The changed data storage means 3 includes an entry area in which the address of each data is written, and a changed content area in which the changed content indicated by the entry itself is written. As for d data, the entry area contains d
The address of the data is written, and in the change content area, the type of change indicating whether it is insertion or deletion, the content of the change data, that is, d data, the change position within the editing object, and the restoration time if necessary are written. Regarding all data, the addresses of all data are written in the entry area, and the entire data to be edited is written in the change content area.

Next, the state restoration operation will be explained.

When the instruction to restore the state and the instruction of the point in time to restore are input, the man-machine interface 1 sends these data to the restoration procedure determining means 5 via the signal line (C). Upon receiving these specified data, the restoration procedure determining means 5 takes in the changed data stored from the changed data storage means 3 via the signal line, determines the restoration procedure, and performs the restoration. The procedure is sent to the restoring means 6 via the signal line (l), and the changed data storage means 3 is instructed to read out the changed data necessary for restoring the state via the signal line (l). The modified data thus read out is sent to the restoring means 6 via the signal line (power).

Upon receiving the restoration procedure from the restoration procedure determination means 5 and the change data from the change data storage means 3, the restoration means 6 restores the editing target to the specified state according to the restoration procedure determined using the change data, It is sent to the man-machine interface 1 via the signal line (K). As a result, the editing object restored to the instructed past state is displayed on the display device of the man-machine interface 1.

Next, the state restoration operation will be explained. State restoration is performed by tracing d data from all data, but when deciding on the restoration procedure, there are two methods: select the path that minimizes the time required for restoration, and select the path that minimizes the amount of data required for restoration. There are two ways to do this.

First, in the former case, when a restoration time point is specified, the restoration procedure determining means 5 determines the restoration time of d data accumulated between the restoration time point and all the data accumulated before that point, Calculate the restoration time of the d data accumulated between the time of the restoration and all the data accumulated after that,
Compare these.

A process is performed to determine the path with the shortest restoration time as the restoration procedure. Specifically, it is as follows. Assume that the changed data storage means 3 has stored changed data as shown in FIG. 3, and that an instruction is given to restore the state after the change at time t+a.
2. When the first method is adopted, the restoration procedure determining means 5 selects the d data d+a+d++ +a+2nd accumulated between the restoration time and all data C before that.
+a+d+4 restoration time sum ΔT1 (=△t, d 1
11+Atd day+△td12+△t, □3-+-△td
lA), and d data di6. cL+6, d1□+
Sum of restoration times ΔT2(2Δtd7.+
△t, +a(-△t,, 1-r(-Δt,, IIQ+
△t1. o) and compare them to find 8T, ≦△
If T2, sequentially d data d+e+d from all data all C
Select the procedure to restore +++d+a+d+s + d+a, and if △T+>△T2, sequentially restore d data d+e, ds+d+7+d+s+d+s from all data.
Select the steps to restore.

Next, in the method of selecting a path that minimizes the amount of data required for restoration, when a restoration time point is specified, the restoration procedure determining means 5 selects a path that minimizes the amount of data required for restoration. Calculate the sum of the amount of d data accumulated between the time of restoration and all the data accumulated after that time, Performs processing to determine the path as a restoration procedure. Specifically, taking the case of FIG. 3 as an example, the restoration procedure determining means 5 determines that
Sum of data amount B2 of I+d+2+d+3rd+a,
and d data d+li+d+6+d+t+d+a+d+
Calculate the sum B2 of the data amount of * and compare them to find △
If B, △B, sequentially d data d from all data C
lll, d mouth, d I 2 + d3 + d l
4, and if ΔB+>ΔB2, sequentially restore d data d+9+d+e+ from all data.
Select the procedure to restore d l 71 d + 6+ d I 6.

It is optional whether to adopt Isukoma's method as a method for determining the restoration procedure, but if you decide based on the required restoration time, 1
．． ! It goes without saying that the restoration time must be stored in the modified data storage means 3.

In the above description, if all data has not been accumulated after the designated restoration time, all y-,9 at the current time is assumed to be used as all data and evening.

In the son's movement, a total of 14 hours for determining the restoration procedure is shortened by 7'', so it can be ignored. "Sword, ~, the composition of Figure 1 is Ha-do. Of course, it is composed of A and Sonoto. It can also be +7 consisting of -a'-i).

The 1-1 Ap 3 embodiment of Komyo has been described above, and the second embodiment will now be described.

FIG. 11 shows the configuration of a second embodiment of the present invention, and the second configuration is the configuration shown in FIG.
I) The data creation means 7 creates the (=j added configuration?" In the following explanation, if it overlaps with that of FIG. 1, the explanation will be omitted.

The D data creation means 7 creates D data and its restoration time. The D data is data that has been organized and summarized all the d data created since the previous D data accumulation so that the state can be restored more efficiently than in the first embodiment, and the details will be described later. It will become clear from where you go.

When some kind of editing is performed on the editing target and a change occurs (Ma), the storage data determining means 4 determines whether to store d data, D data, or all data in the changed data storage means 3. However, there are three methods for determining this accumulated data, as in the -1-2 first embodiment.

First, when determining the accumulated data based on the first method, that is, the restoration time, the accumulated data determining means 4 uses d
When deciding whether to store data, D data, all data, or evening data in the changed data storage means 3, the D data and d data are traced from the previous storage point of all data, and the editing target is changed to the current state. This is performed based on the forward restoration time required to restore the data to the current state, Tpa, and the forward restoration time required, Tpo, to restore the editing target to its current state by tracing the d data from the point of accumulation of the previous D data. It is. That is, in the initial state, all data is stored in the changed data storage means 3, and each time the stored data determining means 4 receives a signal from the man-machine interface 1 indicating that a change has occurred, the stored data determines T F 6 and TFD. Calculate T1. is greater than or equal to the preset upper limit Tn+u+p, a decision is made to accumulate all data and d data after the change,
If Tpn is greater than or equal to the preset upper limit Tn,,D, the d data strings created after the last accumulated D data, including the d data created this time, are organized and the D data is stored. At the same time, it is determined to create and store the d data created this time, and in other cases, it is determined to store the d data. In this way, the D data is not stored alone, but is stored as a pair with the d data created in accordance with the current change in the editing target.

As will be clear from what will be described later, this allows the processing time for state restoration to be shorter than in the first embodiment.

Note that if no D data has been accumulated before, T p
It is assumed that the accumulated data is determined as D = T p^. In addition, since D data is data that has been organized so that d data strings can be efficiently restored, it is clear that it can be restored in a shorter time than when restoring each d data string individually. The time required to restore is smaller than the total restoration time of the d data strings included in the D data. For example, a certain D data consists of three d data d+, d2. Assume that da is organized and summarized, and the restoration time of each of these d data is △
td+, △td2. If △tda, then the restoration time △tn of this D data is △tn<△tdI ten △tdl! +Δtd3.

The two upper limit values Tnamo and T and lI\8 may be set by taking into consideration the storage capacity of the changed data storage means 3, etc. It is clear that if the storage capacity is large, it is a good idea to accumulate all data relatively frequently in order to shorten the restoration time, and if the storage capacity is small, it is a good idea to accumulate D data. It is.

The stored data determination process according to the first method will be specifically explained as follows. Taking the case shown in Figure 2 as an example,
The accumulated data determining means 4 calculates Tpp and T F n. In the case of Fig. 2, all the data accumulated at time T, a are sequentially d+, (and, to restore the editing target to the current state by tracing the d data of da, d4, TFA= TFD=△1d+++Δtda+△taa+△t
Although it will take the time of aj, Tp. ≧T. □
If so, the storage data determining means 4 determines to store all the data changed by the current editing and the d data d4 created this time.

Further, when TFD≧Tn11xn, the storage data determining means 4 determines to store D data, and the signal line (
1), the changed data storage means 3 is instructed to that effect, and a start signal is generated on the signal line (su) to start the D data creation means 7 and create the D data. As a result, the D data creation means 7 takes in the d data d4 created this time via the signal line (a), and also receives the d data d4 that has been accumulated so far from the changed data storage means 3 via the signal line (b). Read the data d+, da, and da, and convert these four d data d1. d2. Da and d4 are divided into deletions and insertions, and organized by sorting them in the order of the character string positions. The D data D created in this way is stored in the changed data storage means 3 via the signal line (C), but at the same time, the d data d4 created this time is also stored via the signal line (A). Accumulated. The situation at this time is shown in FIG. In addition, the restoration time △tDI of the amount of D data D in this case is △1+++<Δ1d++Δtd2+△tda+△tda
Of course it is.

Moreover, T pll < Tnoxo and T pn < T
IIaxn, the accumulated data determining means 4 d
It is determined that only data dA is to be stored.

Next, when the second method is adopted as the accumulated data determination method, the process is as follows. At this time, the accumulated data determining means 4 determines, for example, the total data amount B, 11 since the previous all data accumulation, and the total data amount B since the previous D data accumulation.
nm++ is calculated, and if Ba1l≧B, it is decided to accumulate all data and the d data created this time.N
If BDall≧Bthp, it is decided to create D data by organizing the d data since the previous D data accumulation, including the d data created this time, and to store the same number as the d data created this time. and otherwise d
Data is slow.

is decided to be accumulated. Note that N Bth++Bt
h21 is a preset threshold value.

In addition, when the third method described above is adopted as the accumulation data determination method, for example, if the number of accumulations of d data since the previous I]de data accumulation has reached the preset number N In this case, it is determined that D data and d data will be stored next time, and after storing D data a preset number of times since the previous storage of all data, it will be determined that all data will be stored next time. .

Thereafter, stored data is determined in the same manner.

The data structure of the changed data storage means 3 is the same as described in the first embodiment for d data and all data, but for D data, the address of D day/evening is written in the entry area, The changed content area includes a data array for inserted content, that is, an array of changed data and its changed position, a data array for deleted content, that is, an array of changed data and its changed position, the entry address of the previous D data or all data, and the following. The entry address of the D data or all data, and if necessary, the restoration time required to restore the changes are written.

Next, the state restoration operation will be explained.

When the restoration time point is instructed from the man-machine interface 1, the restoration procedure determining means 5 determines the restoration procedure. As in the first embodiment described above, the restoration procedure determination means 5 determines the restoration procedure based on the restoration time required. how to decide based on;
There are two methods of determining this based on the amount of data required for restoration.

The method for determining the restoration procedure based on the required restoration time is as follows.

In this embodiment, state restoration is performed by tracing from all data to D data, and finally by tracing D data. Therefore, the restoration procedure determining means 5 traces the D data from all the data accumulated before and after the restoration time, and finally traces the d data to minimize the processing time required to restore the state at the designated restoration time. The path will be determined as the restoration procedure, but
Specifically, it is as follows. Now, it is assumed that the changed data storage means 3 has accumulated change data as shown in FIG. The following four paths (1) to (2) are possible as the path.

■All A +d Ie ” d + s→d+7→D4→
D3 → die → d11 → Restoration time ■ All A → d + s → d, * → d + t → D, → d + s → d +
2 → At the time of restoration ■ All B → D, → D2 → d＋++”dz → At the time of restoration ■ All B
= D + → D2 → D3 Pass d+3 → d+2 → Restoration time point Therefore, the restoration procedure determining means 4 calculates the restoration time by adding the restoration time of each changed data for these four restoration paths, and determines the restoration time. The path with the minimum time is determined as the restoration procedure, and the determined restoration procedure is sent to the restoration means 6, and the changed data storage means 3 is instructed to send changed data necessary for the restoration procedure to the changing means 6. Instruct. Through the above operations, the editing target is restored to the specified state and displayed on the display device of the man-machine interface 1.

In the case of FIG. 6, in the conventional state restoration method, 10 steps are required to restore the state from the current point to the changed state at time 1++, but the present invention requires a smaller number of steps; It is clear that the invention can speed up state restoration.

In addition, when the current time is time te9 in FIG. 6, all the data A can be reread as the current state and the restoring procedure can be determined in the same manner as described above.

As described above, by writing the data of each change in the change data storage means 3 with the time required for restoring it, the time required to restore each change can be almost calculated using this additional data alone. , the total restoration time can be found by adding them. Note that the calculation time for determining the restoration procedure is sufficiently short compared to the restoration process, so it can be ignored.

Next, a method for determining a restoration procedure based on the amount of data required for restoration is as follows. Taking the case of FIG. 6 as an example, the restoration procedure determining means 5 calculates the amount of data required for restoration for each of the above four paths, and determines the path with the least amount of data as the restoration procedure.

Which method to adopt as the restoration procedure determination method is arbitrary, but when determining based on the restoration time required, it goes without saying that the restoration time must be stored in the changed data storage means 3. .

Note that, similar to the configuration in FIG. 1, the configuration in FIG. 4 can be configured using either hardware or software.

Although the embodiments of the present invention have been described above, it is clear that the present invention is not limited to the above embodiments and that various modifications are possible. For example, in the first and second embodiments described above, it is assumed that all data is accumulated in the initial state, and the accumulated data is determined based on parameters such as the forward restoration time or data amount. Based on the state of the object, the data to be accumulated may be determined in accordance with the time required for restoration or the amount of data when restoring from there retrospectively.

Furthermore, in the above embodiment, the restoration time of d data is created by the d data creation means, and the restoration time of D data is created by the D data creation means, but they are created by the accumulated data determination means. It is also possible.

[Effects of the Invention] As is clear from the above explanation, according to the present invention, instead of storing only differential data as in the past, all data is stored in some places, so that specified restoration Since the state can be restored using differential data starting from all the data accumulated at a point in time close to the state, it is a function that can quickly restore the desired state regardless of the past point in time to be restored. can be realized.

In addition, you can restore from all data before or after the specified restoration point.
You can select the shortest recovery path and perform fast recovery.

Furthermore, with regard to accumulation of changed data, by writing the restoration time as well, the entire restoration time can be easily determined, and the restoration procedure can be determined at high speed. Further, by using the partial sum of the restoration time or the partial sum of the data amount of the stored difference data as a judgment condition of the storage data determining means, it is also possible to perform differential data storage and restoration more efficiently. .

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a first embodiment of the state restoration method according to the present invention, FIG. 2 is a diagram for explaining the processing of the accumulated data means in the first embodiment, and FIG. A diagram for explaining the processing of the restoration procedure determining means in the first embodiment,
FIG. 4 is a diagram showing the configuration of a second embodiment of the state restoration method according to the present invention, FIG. 5 is a diagram for explaining the processing of the accumulated data means in the second embodiment, and FIG. FIG. 7 is a diagram illustrating a configuration example of a conventional state restoration method, and FIG. 8 is a diagram illustrating a data structure within the differential data storage means. DESCRIPTION OF SYMBOLS 1...Man-machine interface, 2...D data creation means, 3...Change data accumulation means, 4...Accumulated data determination means, 5...Restoration procedure determination means, 6...Restoration means, 7...D data creation means. As of the time in FIG. 1, FIG. 2 shows the total arrangement of data in the changed data storage means A d. d. (1P) Restoration time Δt 41 Δt. △t. Mountain, 4) Figure 4 Figure 5 Figure 3 △t U △Lt △t 13 tゎCurrently △tas △t. △t at △(. BO0.) △t□. △t al △t 412 △t,,. △t6.4 △t 41@ △t Ull △t, 17 △t 1111 profit, 1゜) △t, ゎFigure 6 △t ml △tit △t 43 m-) △t engineering △t. △Lt △t. α~) △t al. Δt al Δt4. . Polish π,) △t1,4 △t, 1° at the moment △[, 1□ △t ml. (Kari, 1.) △t0

Claims (12)

[Claims] (1) In a state restoration method that restores the state based on the difference data accumulated each time the editing target is changed, if the accumulated state of the difference data satisfies predetermined conditions, editing at that point is performed. Accumulate all target data and differential data, and when state restoration is instructed, use the differential data from all data accumulated before or after the state to be restored to change the editing target to the specified past state. A state restoration method characterized by restoration. (2) The state restoration method according to claim 1, wherein the predetermined condition is set based on the time required for forward restoration from the previous all data accumulation point to the current time. (3) The state restoration method according to claim 1, wherein the predetermined condition is set based on the sum of data amounts of differential data after the previous time point of all data accumulation. (4) The state restoration method according to claim 1, wherein the predetermined condition is set based on the number of times differential data has been accumulated since the previous time when all data was accumulated. (5) The state restoration method according to claim 1, wherein a path for the state restoration is selected such that a path requiring a minimum restoration time is selected. (6) The state restoration method according to claim 1, wherein a path for the state restoration is selected such that a path requiring a minimum amount of data for restoration is selected. (7) In a state restoration method that restores the state based on difference data accumulated each time the editing target is changed, the difference data includes the first difference data created when the editing target is changed, and the plurality of first difference data. and second difference data created by organizing the difference data, and if the accumulation state of the first difference data satisfies a predetermined first condition, the previous second difference data is
Organize all the first difference data after the time of difference data accumulation to create second difference data, accumulate the second difference data together with the first difference data created this time, and
Or, the second difference data storage state is predetermined.
If the conditions are satisfied, all the data to be edited at that point and the first difference data are accumulated, and when state restoration is instructed, the first difference data is stored from all the data accumulated before or after the state to be restored. and/or a state restoration method characterized by restoring the editing target to a specified predetermined past state using the second difference data. (8) The predetermined first condition is set based on the required time for forward restoration from the previous second differential data accumulation point to the present time, and the predetermined second condition is 8. The state restoration method according to claim 7, wherein the state restoration method is set based on the forward restoration time required from the accumulation point to the current time. (9) The predetermined first condition is set based on the sum of the data amounts of the first difference data after the previous second difference data accumulation time, and the predetermined second condition is 8. The state restoration method according to claim 7, wherein the state restoration method is set based on the sum of data amounts of all data after the point in time when all data is accumulated. (10) The predetermined first condition is the previous second condition.
The predetermined second condition is set based on the number of times the first difference data is accumulated after the time of accumulation of the difference data, and the predetermined second condition is:
8. The state restoration method according to claim 7, wherein the state restoration method is set based on the number of times the second difference data has been stored since the previous time when all data was stored. (11) The state restoration method according to claim 7, wherein a path for the state restoration is selected such that a path requiring a minimum restoration time is selected. (12) Claim 7, wherein the state restoration path is selected as a path that minimizes the amount of data required for restoration.
State restoration method described.