JPH06103502B2 - Drawing display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a drawing display device formed by connecting a graphic display device to a host computer.

B. Outline of the Invention The present invention is a drawing display device having a function of managing drawing information by a host computer, displaying a requested portion of the drawing information on a graphic display device, and changing the drawing information in a simulated manner. When changing, first copy the current contents to be changed to a save area in the segment buffer with a different name, and if the remaining capacity in the segment buffer is insufficient, host the change history without using the save area. It is recorded by a computer, and when the current state is restored, the other name is returned to the original and only the drawing information of the segment buffer to be changed is restored based on the recorded contents. It is possible to achieve high-speed recovery of the segment and save the capacity of the segment buffer.

C. Problems to be solved by conventional technologies and inventions Maps can represent various human activity information such as local natural conditions, population facilities, and population / economic conditions, and have long been used for administrative purposes. It was Even now, the national government, local governments, fire departments, etc., use it as a basis for regional planning and management. In addition, in public enterprises such as electricity, telephone, and gas, we have our own facilities (power lines, telephone lines,
For the planning and management of gas pipes, the drawings of the facility are used on the map. These maps and facility diagrams are drawn as drawings on paper, and the information drawn is hereinafter called drawing information.

In recent years, attempts have been made to draw these drawings with a computer and process drawing information with a computer. This was pioneered by the United States and has been carried out since the 1960s. Such a computer system is called a drawing information processing system. Today, it is used by federal, state, and local governments, as well as by public companies such as electricity, telephone, and gas, and private companies such as marketing.

In Japan, we started research later than in the United States, but we have started researching databases, computer graphics, etc.
It successfully absorbs the technological development during that time and shows its own development. It can be said that the government, local governments, fire departments, and public enterprises such as electricity, telephone, and gas have finally reached the stage of practical use.

A feature of each of the drawing information processing systems is that a drawing display device can be connected to display a drawing. The host computer manages the drawing information, and controls to display the requested portion of the drawing on the graphic display device according to the operator's request. The graphic display device displays a requested portion of the drawing in response to a request from the host computer. In the drawing information processing system, a part including a part that realizes a function of displaying a drawing by the host computer and the graphic display device is hereinafter referred to as a drawing display device.

In a drawing information processing system, it is basically used to proceed with processing by an interactive operation with an operator centering on a drawing displayed on a graphic display device.
Therefore, the responsiveness of the drawing display function is strongly required. However, since the host computer performs various general-purpose tasks in addition to the drawing display processing, the steady load is large, and the effect of improving the performance of the host computer cannot be expected. Rather, the steady load tends to increase due to the increase in information to be processed and the demand for higher functionality, and the display processing on the host computer becomes a burden. Therefore, in order to reduce the load on the host computer and improve the responsiveness of the display processing, there is a tendency that the graphic display device becomes more intelligent. That is, most of the graphic display functions are performed by the graphic display device. Less than,
The graphic display device having the configuration shown in FIG. 8 will be described in detail.
The definitions of abbreviations used in the following description are as follows.

・ HIF ... host interface.

・ SB .... Segment buffer.

-MTX ... Matrix calculator. Matrix calculator.

・ CLP ... Clipping device.

・ DDA ... Digital differential analyzer. Digital Vector
Generator.

・ FB .... Frame buffer.

・ LT .... Lucky up table. Also known as a color map.

・ IM .... Implant machine. Input device.

・ VIF ... video interface.

・ TB .... table.

· AD .... address.

・ Pn .... Plane n. (N is an integer equal to or greater than 0) First, the graphic display device 2 has a host interface (HIF) that transmits and receives data to and from the host computer. The HIF receives various display instructions and graphic information from the host computer and transmits them to the display processor (CPU). In addition, various display related information can be sent to the CPU at the request of the host computer.
Received from and sent to the host computer.

SB is a memory that stores graphic information of descriptive expressions (numerical values, symbols). The graphic information is managed in a hierarchical structure.
The lowest layer is a concrete figure entity (display figure shape, position coordinates, display color, etc.). On top of these, there is information on various attributes (visual attributes, detection attributes, etc.) regarding the actual state of each figure. It should be noted that the position coordinates of the graphic entity do not directly indicate the pixel position on the tube surface, but are called coordinates on a virtual large screen, so-called world coordinates.

With respect to the graphic information stored in this SB, the graphic information in the range requested to be displayed (a rectangular area determined by world coordinate values) is cut out. For this cutting process,
A matrix calculator (MTX) that performs parallel movement and rotation conversion of the displayed figure, and a clipping device (CLP) that removes the part that extends beyond the displayable area corresponding to the CRT monitor (CRT) are available. In addition, a digital differential analyzer (DDA) is provided that expands the segment of the graphic information of the cut descriptive representation into the ON / OFF information of the bit on the frame buffer (FB) corresponding to the display position coordinate. .

The FB is a memory that has a bit corresponding to each pixel on the tube surface of the CRT in a one-to-one correspondence with at least the number of pixels on the tube surface. In color display, a plurality of memory planes are provided, and a set of bits corresponding to the same pixel is arranged in each plane to form column data, which is used as a color code of the pixel corresponding to the bit. Further, in recent years, there is a lookup table (LT), which is also known as a color map, in which color codes are stored in advance, the column data of the bit is used as an address, and the contents of the address in LT are read out.
Graphic display devices using color codes of corresponding pixels have become mainstream. In such a graphic display device, overlay priority display is possible. That is, first, a priority order is set for each plane of the FB, and a priority order that indicates which one is prioritized to be displayed when the figures to be displayed similarly are overlapped is set. Next, for each LT address, store the display color code of the graphic to be developed on the plane with the highest priority among the combinations of planes whose bit contents are on, in the LT portion of that address. . Then, the graphic in the display range is cut out from the SB, and each graphic is bit-developed on the plane of the FB corresponding to the priority. On the other hand, when some figures in each plane overlap, LT is referred to by using the bit string corresponding to the pixel of the overlapping part as an address, and the address part corresponds to the "on" bit of the address. Since the color code of the highest-priority display graphic in the case where the plane graphic sets overlap, the overlay priority display is realized. 10th
This will be described with reference to the figure. There are display figures ●, ▲, and ■, and the priority of overlay priority display is in this order.
The display colors are red, green, and blue. The priority order of FB planes is P2, P1, P0 in order from the highest. The displayed figures ●, ▲, and ■ shall be bit expanded to P2, P1, and P0, respectively. It is assumed that a set of bits corresponding to one pixel read from each plane of FB are arranged in the order of P2, P1, P0 from the highest rank and serve as a reference address of LT. Below is the combination of overlapping graphics and the corresponding LT in each pixel.
Indicates the reference address and the LT content of the address. (The place where the bit content of the address is × can be either 0/1.) <Combination of figures><LT reference address><LTcontent> 1. ●, ▲, ■ 1 ×× red 2. ● , ▲ Same as above Same as above 3. ● Same as above 4. ▲, ■ 01 × green 5. ▲ Same as above 6. ■ 001 Blue 7. No overlap 000 Background color The figure also shows the combination of overlapping figures. The numbers written on the surface surrounded by the line segments are the numbers given to the above-mentioned graphic overlapping combinations. The screen displayed on the tube surface as described above is as shown in the figure.

LT is a table that stores the brightness of the three primary colors of R, G, and B. A unique color is expressed by combining the R, G, and B luminance colors stored at each address.

The video interface (VIF) reads the contents of FB and uses the bit string corresponding to each pixel as an address to read the color code of LT to read the video signal (R, G,
B, separate, composite) and sync signal to CRT (vertical sync signal: VD, horizontal sync signal: H)
D) is generated. These operations are independent of the control of the CPU and are always executed at high speed and cyclically. The mechanism until the video signal is generated will be described with reference to FIG. The VIF generates a bit address (FBAD) corresponding to a pixel for each plane of FB. Thus, the read bit contents are arranged at respective predetermined positions to create the LT reference address. The content of the corresponding LT is read out in R, G, B units by this LT reference address. The read contents are sent to the DA converter. Here, D-A conversion is performed to generate R, G, B video signals, respectively. The above processing is performed one after another in the order in which the pixels are arranged. Since these are executed at extremely high speed and cyclically, they appear as a single screen to human eyes, aided by the afterimage phenomenon.

The CRT is a rendering method using the raster scan display method. That is, R for each pixel,
Receiving G and B video signals, radiating an electron beam of corresponding intensity to the pixel position on the phosphor screen and emitting light at each brightness R,
Various colors are displayed by combining the colors of the G and B fluorescent points. Further, the designation of pixels, that is, the radiation position of the beam is controlled by the horizontal synchronizing signal and the vertical synchronizing signal. That is, the electron beam is scanned in the horizontal direction from the upper left on the screen, and the required number of scanning lines are sequentially made 30 to 60 times per second to the lower right.
The numerical value of 30 to 60 times is called a vertical scanning frequency (reflecting rate), and generally, a numerical value close to the lower limit is set within a range where flicker does not occur.

The CPU analyzes and executes input information from the host computer or IM. However, the specific processing is mostly performed by each dedicated processor (MTX, CLP, VIF, etc.), and in practice, they are often controlled.

The input device (IM) is used by an operator to input various information to the graphic display device. There are various types depending on the application. There is a keyboard as standard. Devices for inputting coordinate values include digitizers and tablets. In addition, as a means for moving a figure or a cursor on the tube surface, there are a joystick, a track ball, and the like.

As described above, in the drawing display device including the host computer and the graphic display device, the drawing information is managed by the host computer. This can be considered as having a virtual continuous large drawing in the computer. In the conventional method, when there is a display request from the operator, the host computer sends the drawing information of the requested portion in the virtual large drawing to the cutout graphic display device. The graphic display device that has received it stores each graphic element of drawing information in SB in the form of a segment, bit-expands it in FB, and displays it on the screen. In this method, it takes a considerable time to transmit a large amount of information between the host computer and the graphic display device and to register a segment in the graphic display device, and it takes a long time from the display request to the display on the screen. As described above, the responsiveness is the maximum requirement for the drawing display device, and this method has been a problem.

Recently, a drawing display device is configured using a large-capacity (about 4 MB) SB graphic display device, and all graphic information corresponding to all drawing information managed by the host computer is registered in the SB at startup and operated. Sometimes, when there is a display request, the host computer gives an instruction only to the display range to the graphic display device, and the graphic display device cuts out the graphic information of the requested range from the graphic information corresponding to all the drawings in the SB and bit-expands it to the FB. A method of displaying is being developed. This is because the amount of transmitted information is small when a display request is made and segment registration processing is not required, so that an arbitrary drawing location can be displayed at high speed. We have realized a drawing display device with extremely good responsiveness.

By the way, in recent years, in the drawing information processing system, a function of changing drawing information in a simulated manner while actually seeing is desired. In other words, the function is to change the drawing information while visually confirming it on the drawing display device, and restore it again. In other words, it is a drawing information change drawing simulation. For example, in a case where a local government newly plans a new road, a water supply, or a new construction or removal of public goods on a drawing. Similarly, in a power company, a telephone company, or a gas company, when a plan for new installation or removal of a power line, a telephone line, or a gas pipe is performed on a drawing. In the drawing display device,
Display and show how water, public facilities, power lines, telephone lines, gas pipes, etc. are newly installed or removed. If the simulation is stopped, the original drawing information is restored and the current drawing can be displayed.

In the above function, it is naturally required that the responsiveness of the drawing change process is good, but after the simulation is further stopped, the function of returning to the original drawing information and displaying it can be required. This is because the various tasks that are carried out based on the current drawings are more practical problems.
This is because the current drawing must be able to be displayed when the need arises at any time while executing the simulation. For example, when an accident occurs in a power line under the jurisdiction of an electric power company, it is necessary to display the current drawing, grasp the accident area, and promptly perform an accident recovery operation. Similarly, if a fire breaks out in the area of jurisdiction,
It is necessary to display the current drawings, identify the fire area, and immediately rush to the site to carry out fire fighting. Also,
Even if there is no such urgency, the work executed based on the current drawing information is prioritized. The current drawings are also frequently used. Therefore, it is required to quickly return to the original state even during the simulation. Hereinafter, returning to the original drawing information that has been modified in a simulated manner is called current restoration.

In this simulated change process, it is problematic from the viewpoint of data protection to change the real data for the current drawing information managed in the host computer. For example, it is possible that the host computer goes down during the simulated change process, and the current drawing information remains unchanged. Therefore, when making a simulated change, a method is considered in which the genuine (current) drawing information is first copied to another area in the storage device and a simulated change process is performed on the copied drawing information. . During the mock change process,
Since no operation is performed on genuine drawing information, complete data protection is established. Further, in this method, when returning to the current state, it is only necessary to discard the simulated drawing information as it is, no data operation is required, and the operation can be instantly restored. Therefore, the response of the processing of the host computer is very good.

However, there is a problem in adopting the above method in a graphic display device that stores all drawing information (format of graphic information). That is, the storage area (SB) of the graphic display device for storing the drawing information is not so large, and the area for storing both the current drawing information and the simulated drawing information cannot be secured.

The memory device of the graphic display device is an IC memory, and it is technically difficult to mount an ultra-large capacity device at this stage.
It also becomes expensive. On the other hand, the host computer can have a storage area that can be said to be practically infinite by utilizing an auxiliary storage device such as a disk or a virtual storage mechanism.

Therefore, the host computer executes the simulated change processing on the simulated drawing information, but the graphic display device has a method of directly changing the current drawing information. In this way, when the current state is restored, the restoration process on the host computer side can be executed instantly, but the figure display device has actually changed the current drawing information, and therefore cannot be easily restored. In order to restore the drawing information in the figure display device to the current one, all the current drawing information managed by the host computer must be re-registered as in the system startup. However, this requires a long time for the transmission of a large amount of information and the segment registration processing, and the responsiveness of the current restoration becomes extremely poor.

The present invention has been made as a result of studying various methods to solve such problems, but in order to make it easier to understand the features of the present invention, the methods studied up to the present invention are I will briefly explain.

Regarding the method studied first, the host computer processes the current drawing information, but at the start of the simulation change processing, the current drawing information is stored in an area provided separately in the host computer, and this is processed by the host computer. set to target. At the time of simulated change, the change history of the drawing information in the graphic display device is recorded in, for example, the recording unit provided in the host computer, and when the current state is restored, the recorded contents of the recording unit are referred to, and only the changed portion is changed to the current drawing information. Try to bring it back. According to this method, as compared with re-registering all of the drawing information again as a segment, useless transmission processing and segment registration processing can be eliminated, and the current state can be efficiently returned in an extremely short time.

By the way, in this method, when the number of changes to the same segment is large, the change history is recorded one by one, but when returning to the current state, the change history return operation is performed in the reverse order of the recorded order. Therefore, the restoration process becomes slower as the amount of change history in the recording unit increases. Therefore, in order to cope with such a case as well, the above-mentioned method is advanced one step further, and a method of recording only the difference between the simulated drawing at the present time and the current drawing is considered for recording in the recording unit. However, in the current restoration by this method, if the change type of the segment to be restored is "replace" or "delete", refer to them to restore the current contents of the change history in the recording section, and perform the replacement or registration operation for that segment. Do. (For the segment of change type "new", perform the operation of "delete".) This operation is the segment ID
The entire contents of B, such as the shape, position coordinates, and colors, must be specified once again. Most of the standard graphic display device segment / IDB operation commands are such commands. Therefore, a large amount of information (segment / IDB operation command) is transmitted to the graphic display device, which requires a considerable transmission time. Further, there is a lot of segment / IDB operation processing in the graphic display device, which requires a considerable processing time. Therefore,
This is an obstacle to high-speed current recovery processing.

For this reason, the present inventor separately provides a save area in the SB, copies the current contents of the change target with a different name to the save area at the time of simulated change, and restores the current restore target in the save area when restoring the current. In addition to returning to the name of, the method of deleting the segment of the drawing information to be restored of the drawing information that has been the processing target in SB so far is being considered. According to such a method, it is not necessary to replace or register the segment to be restored, and the current restoration can be performed very quickly.

Now, in the drawing information processing system including the drawing display device, the information to be managed gradually increases during the normal operation over a long period of time. This is because the local industrial / economic environment, social environment, and natural environment are developing and changing. In such a case, the storage capacity of the system becomes a problem. That is, is it possible to cope with an increase in the amount of information to be managed. The host computer is equipped with a storage device having a sufficient capacity in anticipation of its increase at the design stage. Further, even if the capacity becomes insufficient, it is possible to cope with it by adding an external storage device. However, in the case of a graphic display device of a system in which all drawing information is always stored during operation, it is difficult to handle it. First,
It does not have an external storage device. (The external storage device has poor response and cannot be used for display processing.) As mentioned above, IC
There is a certain limit to the memory mounting capacity. for that reason,
At the system design stage, the drawing area that can be managed by the system is decided in anticipation of future increase in drawing information, and the drawing area is designed to have sufficient capacity. Therefore, there will be no shortage of capacity unless there is much. However, considering cost-per-performance, it is unthinkable to have enough room.

Here, consideration will be given to the increase / decrease of the segment due to the simulated change when the above-mentioned save area is used. Replacement,
For the drawing information to be deleted, a save segment is newly created by copying the drawing information immediately before the change. In the case of new installation, the save segment is not created, but the drawing information concerned is newly created as a segment. In the case of deletion, even if the number of saved segments increases, the relevant segment is deleted, so there is no change in the remaining capacity of the SB. In the case of new establishment,
Since the drawing information that will be newly established in the future is designed in anticipation of the increase, it can be absorbed by the margin of the capacity of the SB, and there is almost no problem of capacity shortage during the simulation change. However, in the case of replacement, at the time of simulated change, the relevant segment continues to exist and another save segment is newly created, so the remaining capacity of the SB is surely reduced. Further, the replacement segment is an existing one and is not an increase in future drawing information. Therefore, SB's margin cannot be absorbed. After all, although it depends on how much the saved amount for the replacement segment generated during the simulated change in any case at the time of design is considered, a sufficient amount cannot be secured as described above.

In the situation as described above, when the drawing information increases due to the new installation, the evacuation segment portion due to the replacement at the time of the simulation change is put under pressure. That is, as the drawing information increases, the area for storing the save segment becomes insufficient,
In some cases, it is not possible to make simulated changes by the evacuation method. When the save area is insufficient, the save segment cannot be stored, but since the segment can be replaced, if forced, only the simulated change can be continued. However, since the saved segment of the changed segment is not saved, it is impossible to restore the current state. In addition, if a larger amount of replacement operation is performed than expected in the simulated change, the save area may still run out. As described above, the evacuation method has a problem that the simulated modification itself cannot be performed if the number of drawing information is increased or a large amount of replacement operation is performed.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a drawing display device capable of performing current restoration at high speed and saving the capacity of SB.

D. Means for Solving Problems The present invention provides a host computer with a current drawing information storage area,
The simulated drawing information storage area in which the current drawing information in this storage area is copied as the simulated drawing information, a capacity recognition unit for recognizing whether or not the remaining capacity of the segment buffer is insufficient, and this capacity A recognition method is provided with a method selection section that selects a recording method at the time of recognizing the capacity shortage by the recognition section, and selects a save method at other times, and relates to the graphic information unit to be simulated changed when the save method is selected in the segment buffer. An evacuation area is provided for copying the contents of the current drawing with the name of the evacuation figure information unit, and the change history is stored in the host computer when the evacuation method is selected, and the evacuation figure information unit name of the figure information unit to be changed And a second record for recording the change history of the simulated drawing information when the recording method is selected.

E. Action The drawing information in the simulation drawing information storage area is changed in response to a simulation change request, and is processed by the host computer during the simulation change processing. When the current state is restored, the drawing information in the first recording unit is changed. Referring to the recorded contents, the saved graphic information unit name of the graphic information unit to be restored in the save area is returned to the original graphic information unit name, and the graphic information to be restored in the drawing information storage area in the graphic display device While deleting the unit, referring to the recorded contents of the second recording section, only the drawing information in the drawing information storage area in the simulated display device is restored to the current drawing information.

F. Embodiment (1) Overall Configuration FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention. In this embodiment, the current drawing information is always stored in the host computer 1 and used for actual operation. Current drawing information storage area 3 and simulated drawing information storage area 4 used for simulated changes
When two of the recording unit to record the history of the time the change operation to the drawing information of the graphic display device 2 when the simulated change was rows summer (hereinafter this log), that is, the first log 6 ₁ and the Two
Log 6 ₂ , a recording processing unit 7 for recording the recorded contents of the logs 6 ₁ and 6 _2, a capacity recognition unit 8 for recognizing whether or not the remaining capacity of the SB 5 is insufficient, and this capacity For example, a system selection unit 9 including a system flag is provided which selects a recording system when the recognition unit recognizes the capacity shortage, and selects a save system at other times.

Then, a drawing information storage area 10 and a save area 11 are provided in SB5 of the graphic display device 2. The drawing information storage area 10 is for storing drawing information to be processed by the host computer, and stores current drawing information when the host computer 1 carries out current business processing, and when carrying out simulated change processing. Stores simulated drawing information. The evacuation area 11 is used when the evacuation method is selected by the method selection unit 9, and the current drawing of the graphic information segment changed at the time of the simulation change is assigned to the segment name assigned in the drawing information storage area 10. It exists with a different name from. Below is the save area
The graphic information segment stored in 11 is called a save segment. The visible attribute of the save segment is invisible. This is because the evacuation segment exists in the same SB as the drawing information segment, and the contents of the evacuation segment are the contents of the segments that make up the drawing (positions such as symbols in the drawing). It becomes the target of cutting out. That is, the saved segment, which is the current drawing content, is also displayed during the simulation change process. Since this does not result in a simulated change, the visible attribute of the saved segment is made invisible. (A segment whose visible attribute is invisible is not subject to bit expansion to FB.) In short, the save area does not indicate a contiguous address space on the memory in the graphic display device, but indicates a set of save segments. Is. However, for convenience of management, the saved segment names are often numbers, for example, when they are consecutive.

(2) Management contents of the first log 6 ₁ and functions of the recording processing unit The log 6 ₁ is recorded when the save method is selected. The contents are the change type, the segment name, and the saved segment name.

The change type is a type of difference between different segments between the current simulated drawing and the current drawing, such as replacement, new installation,
There are three types of deletion. The replacement means that the content of the segment, for example, the shape, color, position coordinate, etc., has been changed from the current one. "Newly established" means that the segment does not exist in the current drawing but is newly registered in the current simulated drawing. Deletion means that the segment exists in the current drawing but has been deleted from the current simulated drawing.

The segment name is the name of the segment that is the target of the above change. That is, it is the name of the segment that has been replaced, newly created, or deleted. Since the segment to be replaced or deleted exists in the current drawing, the segment name is the existing one. Since the segment targeted for new installation does not exist in the current drawing, the segment name is newly registered, but it should be unique so that it can be distinguished from the one existing in the drawing or log.

The save segment name is the name of a segment having the same contents as the contents in the current drawing of the segment to be changed. Of course, the segment name is an alias. Now, the purpose of the change history is to restore the simulated drawing to the current drawing, and for that purpose, the contents of the current drawing before the change are necessary. However, in the simulated drawing, the current contents of the segment are lost due to the change. Therefore, the contents of the current drawing are saved as a save segment in the graphic display device. When the change type is "replace" or "delete", the saved segment is the content of the replaced or deleted segment in the current drawing. If the change type is "new", the segment does not exist in the current drawing, so
There is no save segment either.

The recording processing unit 7 has the following functions. That is, first, when a change to a segment is made, whether to search whether any change history regarding the segment is already logged 6 _1. Depending on the result, it processes as follows.

a. The history when for that segment of the unrecorded recording in accordance connexion as log ₆₁ to the change.

b. When recorded, check the change type of the change history recorded for the segment, and the process differs as follows depending on the combination of the change type and the change type.

A. When the recorded change type is "replace" If the change is "replace," do nothing. That is,
Since the recorded change type is "replacement", the segment exists in both the current drawing and the current simulated drawing. Even if the segment content is further changed, it still exists in the current simulated drawing. However, the contents are different from the current drawings. Therefore, the change type is also “replacement”, which is the same as the recorded change history.

When the change is “delete”, the recorded change type is “delete”. That is, since the recorded change type is “replacement”, the segment exists in the current drawing. If the segment is now deleted from the simulated drawing, the difference between the current simulated drawing and the current drawing for the segment is that the segment exists in the current drawing but not in the simulated drawing. That is, the change type is “delete”.
Therefore, the recorded change type of the segment is updated from “replace” to “delete”.

If the change is "new", it does not logically exist. That is, as described above, the segment exists in the current drawing. There is no such thing as a "new establishment". Conversely, such modification processing is not allowed.

I. When the recorded change type is "Delete" No change is possible. In this case, the segment does not exist in the simulated drawing at this point. Therefore, it is impossible to specify a segment that does not exist and change it. Conversely, it does not allow you to specify a segment that does not exist. Moreover, this change also filed by "new", the new segment names so that the segment names which exists as drawings or log 6 ₁ described above can not be used.

C. When the recorded change type is "new" If the change is "replace," do nothing. This is because, in the current simulated drawing, the content of the segment is changed by the "replacement", but it continues to exist. However, since this segment was originally newly established, it does not exist in the current drawing. Therefore, the difference between the current simulated drawing and the current surface regarding the segment is
After all, it is still "new". Therefore, the recorded change history can be left as it is.

If the change is "Delete", it deletes the change history from the log 6 _1. This is because the segment is deleted and does not exist in the current simulated drawing. However, since this segment was originally newly established,
Not present in current drawings. That is, the segment does not exist in the current simulated drawing and the current drawing. Therefore, there is no difference between the current simulated drawing and the current drawing. Yotsute, because the change history is not necessary for the segment is to deleted from the log 6 _1.

The change cannot be "new". Because the segment was originally newly established,
On the other hand, it is logically wrong to establish a new one. Therefore, we do not allow such changes.

The following table summarizes the above log update methods.

Registration: Record the history newly in the log.

Update: Update the already recorded change type to the relevant one.

Delete history ... Deleting the history itself from the log.

―… Do nothing.

―――… It is impossible in such a case.

If the recorded contents are managed as described above, the change history will not exceed one record even if the specific segment is changed a plurality of times (one record or no change history). In addition to the effect of the invention, it is possible to obtain the advantage that even if a segment has been changed many times, it can be restored to the current state by one or less return processes without affecting the number of changes.

Now an example of a correspondence between a part of the content of the drawing information and log 6 ₁ in Figure 2, this figure is a house map, which represent the symbols of the house in one segment. The changes in the drawing information and the log contents of the graphic display device during the progress of the simulated change processing are shown up to. The explanation is given below.
The numbers inside ○ correspond to the figures.

It is current drawing information. Only Seg.B house exists. Of course nothing is recorded in the log.

One house was newly established and newly registered as Seg.A in the drawing information. Since the log has no change history regarding the segment, the change history is newly recorded in the log.

Also, the shape of the Seg.B house has changed. Since the log has no change history regarding the segment, the change history is newly recorded in the log. The log is as shown in the figure.

The position coordinates and shape of Seg.A have been changed. The change type is “replacement”. A change history regarding the segment is already recorded in the log, and the change type is “new”. Therefore, according to the log updating method, no log operation is performed.

Also, Seg.B has been deleted. The change type is “delete”. A change history regarding the segment is already recorded in the log, and the change type is “replace”. Yotsutte
According to the log updating method, the change type of the recorded change history is updated to "delete".

For reference, the figure also shows the current contents in the log.

(3) Management content of the second log 6 ₂ The log 6 ₂ is recorded when the recording method is selected, and the management of this is different from the first log 6 ₁ .
It is to record the contents of the current drawing instead of the save segment name. That is, the contents of the change history 1 record for each segment unit for managing the log 6 _2, change type, a current drawing contents of the segment name and modify. Regarding the recording of the contents of the current drawing, if the replacement is performed, the contents of the original drawing are recorded, and if the contents are new, the contents of the original drawing do not exist and nothing is recorded.

(4) Operation Next, the operation of the above-mentioned device will be described. First, during the current operation, the host computer 1 targets the current drawing information in the current drawing information storage area 3 as a processing target, and performs various processing using this. When starting the simulation change processing, the host computer 1 copies the current drawing information to the simulation drawing information storage area 4 and sets the simulation drawing information as a processing target. The capacity recognizing unit 8 calculates the remaining capacity of the SB5 and the increase / decrease segment amount of the segment to be simulated changed when the save area 11 is used, and compares the calculated remaining capacity with the increase / decrease amount of the segment amount, Recognize whether the remaining capacity is insufficient. That is, if the calculated segment amount is an increment and the value exceeds the remaining capacity, the increment segment due to the change cannot be stored in SB5, so it is determined that the remaining capacity is insufficient, and if it does not exceed the remaining capacity, it is determined that the change is possible. To do. In addition,
If the calculated segment amount is decremented, there will be no shortage of the segment amount. The segment amount of the segment to be simulated changed increases / decreases in the following cases.

A. In the case of new installation The number of new segments in the drawing information storage area (drawing area) 10 increases.

I. When deleting a segment that has no change history No increase or decrease. The segment is deleted from the drawing area 10 but copied to the save area 11.

C. When replacing a segment that has no change history: Increase / decrease of the segment to be replaced in drawing area 10 with respect to the previous segment, and the increment of copying of the previous segment to save area 11.

D. When deleting a segment whose change history is new or replaced The number of the relevant segment in drawing area 10 is reduced.

E. When replacing a segment whose change history is new or replaced: Increase or decrease of the segment to be replaced in drawing area 10 with respect to the previous segment.

Here, for the calculation of the remaining capacity of SB5, the segment amount (capacity) required to store a certain segment in SB5
Can be accurately calculated, the remaining capacity at that time can be grasped based on the total capacity of the SB5 and the calculated segment amount without inquiring the remaining capacity of the SB5 to the graphic display device 2. Therefore, it is possible to recognize whether or not the remaining capacity is insufficient. By the way,
If the amount of segments required to store in SB5 cannot be calculated accurately, make an approximate calculation. This estimation is performed based on an approximate formula for the SB capacity required to store a segment, obtained by an experiment (a segment remaining capacity inquiry is performed after registering a segment, and the value is subtracted from the segment remaining capacity before registration). If the calculation of the segment amount is approximate, the figure display device 2 is inquired about the remaining segment amount, and the accurate remaining segment amount is recognized. The same determination as above is made again based on the remaining segment amount and the calculated segment amount. This is because if the calculation of the segment amount related to the change is an approximate value, the remaining segment capacity recognized at that time is also an approximate value as can be seen from the following formula.

Remaining segment capacity = Immediately remaining segment capacity-Increase / decrease estimated segment amount Since the estimated segment value is higher than that of the experiment due to assumptions, the recognized remaining segment capacity is small and the actual remaining segment capacity is It may be higher than the recognized value. Therefore, if the accurate remaining segment capacity is inquired, recognized, and re-determined, the simulation may be possible.

In this way, regarding the remaining segment capacity, when the remaining segment capacity cannot be accurately calculated when changing the segment, it is always roughly estimated so that the result will be small, and only when it is judged that the remaining segment capacity is insufficient. By inquiring the figure display device 2 about the present remaining segment capacity, grasping an accurate value, and making a determination again, it is necessary to inquire the figure display device about the remaining segment capacity. 0
The processing can be minimized and the constant segment change processing can be performed at high speed.

Next, when the capacity recognizing unit 8 recognizes that the remaining capacity of the SB 5 is not insufficient, the method selecting unit 9 selects the saving method, for example, by setting the method flag to “saving method”. When the save method is selected, first, a certain segment (Seg.I)
If a change is requested to, whether examines whether any change history for the segment has already been logged 6 _1. Depending on the result, it processes as follows.

a. No record-In case of initial change (see Fig. 3) Change the simulated drawing in the host computer as required.

The change target Se in the drawing information storage area 10 in the graphic display SB
Copy the contents of gI to the save area 11 with the name Seg.J. This Seg.J is a save segment for saving the current drawing contents of Seg.I. However, this does not apply when Seg.I is "new". (If it is a "new installation", it does not exist in the current drawing.) Next, change Seg.I as requested. That is, if it is "newly installed"
Newly set gI, replace "Seg.I" if "replace" and "delete"
If so, delete Seg.I.

The change type in the log 6 ₁ [substituted / new / deleted, the segment name [Seg.I], save the segment name [Seg.
J]. As described above, when Seg.I is newly installed, the save segment name is “none”.

The change type in the log _61, segment name, a save segment name records.

b. Recorded-When changed after the second time (Fig. 4 (A) to (C))
(Refer) The processing differs as follows depending on the combination of the recorded change type and the change type concerned. In addition, since it is logically wrong except the following combinations, it is not admitted.

A. When the recorded change type is “new” or “replace” and the change type is “replace” (see FIG. 4A), the simulated drawing information in the host computer 1 is replaced as requested.

Replace the contents of Seg.I in the drawing information in the graphic display device.

No log operation is performed. That is, if the recorded change type of Seg.I is "new", Seg.I does not originally exist in the current drawing. Even if the contents of the segment are changed by replacement, they still exist in the simulated drawing. The difference between the simulated drawings after the changes to the current drawing is a "new" in and become Seg.I, the contents of the log 6 ₁ may be as it is. If the recorded change type of Seg.I is "replace", then Seg.I
Even if the replacement is added to the above, the difference between the current drawing and the simulated drawing is still the “replacement” of Seg.I. The contents of the current drawing of Seg.I have been saved as Seg.J. Therefore, log operation is unnecessary.

I. When the recorded change type is “replace” and the change type is “delete” (see FIG. 4A), the simulated drawing information in the host computer 1 is deleted as requested.

Delete the contents of Seg.I in the drawing information in the graphic display device.

To update the changes type the log 6 ₁ from the "replacement" to "delete". That is, in Seg.I, the recorded change type is "replace".
Therefore, it originally exists in the current drawing. If it is deleted from the simulated drawing due to the change, the difference between the current simulated drawing and the current drawing is the "deletion" of Seg.I. Yotsute is to update the change type of the segment of the log ₆₁ to "delete". The contents of the current drawing of Seg.I have already been saved as Seg.J,
No operation is required for this.

C. When the recorded change type is “new” and the change type is “delete” (see FIG. 4C), the simulated drawing information in the host computer 1 is deleted as requested.

Delete the contents of Seg.I in the drawing information in the graphic display device.

It deletes the history of changes the log 6 _1. In other words, Seg.I does not exist in the current drawings because it was originally created. Due to this change, Seg.I will be deleted from the simulated drawing.
Therefore, Seg.I does not exist in the current drawing and the current simulated drawing, and there is no difference between the two drawings. Therefore, the change history regarding Seg.I must be removed from the log. Incidentally, since there is no save segment for Seg.I which is newly established, the operation related to it is unnecessary.

Then when performing the current recovery processing performs the process of returning reference change history recorded in the log ₆₁ of the drawing information in the graphics display to the current content. It differs as follows depending on the recorded change type.

a. When the recorded change type is “replace” (see FIG. 5), the Seg.I is deleted from the drawing information storage area 8 in the graphic display device. Next, the saved Seg.J of the Seg.I is renamed as Seg.I. That is, the name of Seg.J is changed to Seg.I. The visible attribute of this Seg.I is visible.

The above deletes the current Seg.I that has changed from the current contents by "replacement", renames the saved Seg.J that has the original (current) contents of Seg.I, and renames it as Seg.I. It is reproduced.

b. When the recorded change type is “new” (see FIG. 6), the Seg.I is deleted from the drawing information storage area 10 in the graphic display device.

This is because Seg.I is "new" and does not originally exist in the current drawing, so simply deleting Seg.I will return the contents of the current drawing to the relevant segment.

c. When the recorded change type is “delete” (see FIG. 7), the save segment Seg.J of the relevant Seg.I is renamed as Seg.I.

This is because Seg.I exists in the current drawing and does not exist in the current mock drawing, so rename Save.J that has the original (current) contents of Seg.I and rename Seg.I. The content of the relevant segment is returned to the contents of the current drawing by simply reproducing.

By the way, in the above current restoration, when the segment is the recorded change type “replace” or “delete”, the current content is restored by renaming. Therefore, since there is no transmission processing related to the segment contents from the host computer to the graphic display device and no segment registration operation in the graphic display device, only the rename command is transmitted and the rename processing is performed. Remarkably short.

ID instead for renaming in the management and the save area 11 of the log ₆₁ in the foregoing, the segment unit as graphic information unit said connexion with the example, carried out in segment units
It may be performed in units of B or graphic information larger than the segment.

When the capacity recognizing unit 8 recognizes that the remaining capacity of the SB 5 is insufficient, the method selecting unit 9 selects the recording method by setting the method flag to “recording method”, for example. Instead of using the first log 6 ₁ and save area 11 in this case, the second log 6 ₂ used as already mentioned, change type thereto, the segment name and the current drawing contents to be changed to be changed Is recorded as one record. When the current return, logs 6 ₂ of recorded contents and the current, with reference to the drawing information of the simulated, performs an operation to return the drawing information of the drawing area 10 from mock current one.

Here, of the cases of increase and decrease of the segment amount due to the simulated change, only in the case of C, the segment amount increases due to the saving method. That is, there is a possibility that the segment amount may increase among
C and A, of which A and O are increments only in the drawing area and are the same as the recording method, it cannot be said that the evacuation method causes the increase. In the case of C, there is an increment of the save area in addition to the increase / decrease of the drawing area, and this increment of the save area has a great effect on the increase of the segment amount. Therefore, when it is actually determined that the execution is impossible in the case of C, the method of the simulated change history is switched to the recording method, and the subsequent simulated changes are performed by the recording method. If the recording method is used, there is no increment in the save area, only the increase / decrease in the drawing area.
There is a good chance that simulated changes can be performed.

In the save method, if the segment amount only in the drawing area increases, that is, in the cases of A and O, if it is determined that the execution is not possible, the change cannot be executed even if the recording method is switched.

The reason that the recording method is more likely to be changed by simulation than the save method is that in case (a) there is no increase in the save area, so the total amount is reduced by the segment amount of the drawing area. In the above, there is no increment of the save area, and the total is only the increase / decrease of the segment after replacement with respect to the previous segment. In other words, it is only in the case of new construction that the remaining segment capacity is greatly reduced,
If there is a deletion in another segment, the capacity of the remaining segment is greatly increased, which is offset. Usually, only a slight increase / decrease is repeated by replacement, so that there is sufficient possibility of executing the simulated change.

F. Effects of the Invention As described above, according to the present invention, normally, in the simulated change, the current contents of the change target are given a different name and copied to the save area, and the return target of the area is changed to the original name. Since there is a large number of graphic information units to be restored, the transmission processing to the graphic display device and the segment operation in the graphic display device are remarkably small, and the simulated change processing is performed accordingly. A later current return can be performed very quickly.

When the remaining segment capacity is insufficient, the recording method is switched, so that the simulation change can be continued. Moreover, regarding this recording method, it is only necessary to perform a data operation to restore the original (current drawing) only for the segment recorded in the log. Therefore, as compared with re-registering all the drawing information again as a segment, wasteful transmission processing and segment registration processing can be eliminated, and the original information can be efficiently restored in an extremely short time.

Due to the above effects, it is possible to design the system in which the segment capacity of the save area is saved to the extent that the above effects are not impaired, and the cost per performance is good.

[Brief description of drawings]

FIG. 1 is a block diagram showing the overall configuration of the present invention, FIG. 2 is a correspondence diagram showing the correspondence between drawing information and the contents of a recording unit, and FIGS. 3 and 4 (A) to (C) are simulated. FIG. 5 is an explanatory view showing the state of the changing process, FIG. 5 to FIG. 7 are explanatory views showing the state of the current restoration process, FIG. 8 is a block diagram showing the overall configuration of the graphic display device, and FIG. Explanatory diagram showing the state of
FIG. 10 is a block diagram showing the mechanism of video signal generation. DESCRIPTION OF SYMBOLS 1 ... Host computer, 2 ... Graphic display device, 3 ... Current drawing information storage area, 4 ... Simulation drawing information storage area, 5 ... Segment buffer, 6 ₁ ... 1st recording part, 6 ₂ ... 2nd recording Department,
7 ... Recording processing unit, 8 ... Capacity recognition unit, 9 ... Method selection unit, 10
... drawing information storage area, 11 ... save area.

Claims (1)

[Claims] 1. The drawing information to be processed by the host computer is segment-registered in the drawing information storage area in the segment buffer of the graphic display device, and the graphic information of the display range designated by the host computer is stored in the drawing information storage area. In the drawing display device which is cut out from the drawing information and displayed on the pipe surface, a current drawing information storage area in the host computer and a simulation drawing information storage in which the current drawing information in this storage area is copied as simulation drawing information A region, a capacity recognizing unit for recognizing whether or not the remaining capacity of the segment buffer is insufficient, and a method selecting unit for selecting a recording method at the time of recognizing the capacity by the capacity recognizing section, and selecting a save method in other cases. And the current drawing contents related to the graphic information unit to be changed at the time of simulated change when the save method is selected in the segment buffer. A save area is provided for copying with a save graphic information unit name, and the change history of the change history and the name of the graphic information unit to be changed when the save method is selected are stored in the host computer and the save graphic information unit name. With reference to the first recording section for recording, the second recording section for recording the change history of the simulated drawing information when the recording method is selected, and the recorded content of the first recording section for the current restoration, The saved graphic information unit name of the graphic information unit to be restored in the save area is returned to the original graphic information unit name, and the graphic information unit to be restored in the drawing information storage area in the segment buffer is deleted. A recording process for returning to the current drawing information only the drawing information in the drawing information storage area in the simulated segment buffer, which is referred to by the recorded contents of the second recording unit. A drawing display device in which the drawing information in the simulated drawing information storage area is changed in response to a simulated change request, and is processed by the host computer during the simulated change processing. .