JP2969924B2 - Document processing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document processing apparatus for displaying a document on a bitmap display, such as a workstation or a certain type of Japanese word processor. The present invention relates to a document processing apparatus capable of promptly displaying a corresponding page content after a change even when the content is changed.

2. Description of the Related Art Relatively sophisticated document processing devices such as workstations and certain Japanese word processors often include a display capable of displaying the contents of one page of a document. In such a document processing apparatus, when a change occurs in the document content of one page, for example, when a part of the document content is deleted or added, the bitmap memory for display is completely rewritten. Was to do. Such rewriting has been performed by reading out character patterns one by one according to the contents of the document after the change.

[Problem to be Solved by the Invention] Therefore, even when a part of the display content is changed, the work of completely updating the display content is performed, and it takes a considerable time to redisplay the content. There was such a problem. In particular, in a document processing apparatus which can adopt a multi-window system in which a plurality of windows are displayed on one screen and the contents of a document are displayed on each window, several different documents or documents are displayed on one screen. There is a problem that the page may be displayed and the time until the re-display is performed becomes long.

Accordingly, it is an object of the present invention to provide a document processing apparatus capable of redisplaying the contents of a page at high speed when a part of the display contents of the page is changed.

[Means for Solving the Problems] In the present invention, a bitmap display capable of displaying the contents of a document at least in page units and a block as a unit for dividing one page are prepared.
A bitmap cache memory for storing image information of a corresponding block, a block selecting means for selecting a block whose content has not changed when its content has been changed in a page, and a content not changing The document processing device is provided with image information reading control means for reading out the image information of the block from the corresponding bitmap cache memory and displaying the image information on the bitmap display.

That is, in the present invention, one page is usually divided into a plurality of blocks, and the image information corresponding to each is stored in the bitmap cache memory. Then, when the content of the document was changed, the blocks in which the content was not changed were selected from the blocks of the corresponding page, and those blocks were expanded in the corresponding bitmap cache memory. The image information is displayed on the bitmap memory using the image information. Therefore, although it is necessary to perform the display operation one character at a time for blocks whose contents have changed, image information can be read from the cache memory for those whose contents have not changed. The speed can be increased, and the above object can be achieved.

"Example" Hereinafter, the present invention will be described in detail with reference to examples.

FIG. 1 shows the configuration of a document processing apparatus according to an embodiment of the present invention. This device has a CPU (central processing unit) 11 mounted thereon. The CPU 11 is a bus 12 such as a data bus.
Through various circuit devices. Of which RA
The M13 has a program for controlling this device, and a random data for storing temporary data for controlling.
Access memory. RA of the document processing apparatus of the present embodiment
In M13, bitmap cache memories 13C for individually storing image information in units of blocks are prepared for the total number of blocks.

The disk control device 14 is a device for controlling the input and output of data to and from the magnetic disk 15. Magnetic disk
15 stores the above-mentioned programs and various types of document data. The input circuit 16 is connected to a keyboard 17 so as to input data such as characters.
The keyboard 17 is connected to a mouse 18 as a pointing device.

The display control circuit 21 includes a display 22 such as a CRT.
Is connected, and the data is displayed visually on this. The communication control circuit 23 is connected to another device (not shown) via a cable 24 and can input and output data. For example, print data is cable 24
Through the printer to a printing device (not shown). The image information is read by an image reading device (not shown), and the result is taken into the device of the present embodiment via the cable 24.

FIG. 2 shows the structure of a certain document handled by the document processing apparatus having such a configuration. Document Content 30
Is composed of a plurality of blocks 31, 31 (three blocks in this example). Here, the block 31 is a unit obtained by dividing one page of the document. One or a plurality of these blocks 31 constitute a frame 32. The frame 32 refers to a column in one page. For example, in a document with two columns, the frame 32 is “2”. The page 33 is composed of one or a plurality of frames 32. The route 34 indicates a document to be processed. In the example shown in FIG. 2, the document to be processed has a one-page configuration, and the number of frames is one, and three blocks exist in the frame.

FIG. 3 shows an example of the contents of a document having the document structure shown in FIG. A document 34 of one page is composed of three blocks 31, 31, 31 in this example.

FIG. 4 shows a state of control when a document is displayed by the document processing apparatus. CPU1 shown in Fig. 1
1 sets the numerical value N stored in a predetermined area of the RAM 13 to "1" (step in FIG. 4), and first searches whether or not the bit map cache memory 13C of the first block exists (step). If there is no corresponding memory 13C (step; N), the bitmap cache memory 13C is created for the cache (step). Then, it is determined whether or not the processing of the page has been completed (step). If the processing has not been completed (N), the numerical value N is incremented by 1 and the process returns to the step. That is, the same processing is performed for the second bitmap cache memory 13C of the page and the subsequent bitmap cache memories 13C.

On the other hand, if it is determined in the step that the corresponding bitmap cache memory 13C exists (Y), it is checked whether or not the position of this block has been changed (step). If the position of the block has changed due to movement processing or the like (Y),
The display content of the block is deleted from the currently displayed screen (step). Then, the bitmap cache memory 13C for this block is created again (step).

Even if the position of the block does not change, it is necessary to change the display even when the size of the block changes due to addition or deletion of text in the block. Therefore, the CPU 11 next checks whether the corresponding block has become larger (step). If it becomes larger (Y), the bitmap cache memory 13C of that block cannot be used, and is destroyed (step). Then, a bitmap cache memory 13C corresponding to the size is created (step). The same applies hereinafter.

Similarly, when the size of the block is reduced (step; Y), the display content of the block is deleted from the currently displayed screen (step). Then, the contents of the corresponding bitmap cache memory 13C are destroyed (step), and the bitmap cache memory 13C corresponding to the size is created (step).

In this way, the processing of the blocks is performed one by one, and when all the processing is completed, the operation is completed (step
; Y).

As described above, since the contents of the blocks whose size and position are not changed are stored, when the contents of the bitmap memory for one page are rewritten, the block unit is The respective contents can be read from the bitmap cache memory and used, and the processing for display can be speeded up.

FIG. 5 shows the registration management of the bitmap cache memory of the document processing apparatus. First
The CPU 11 shown in the figure searches the bitmap cache memory 13C of the corresponding block from the list described in detail later (step in FIG. 5), and if the bitmap cache memory 13C exists (step; Y), ends the processing. If not on the list (step; N), RA
An area for the bitmap cache memory 13C is set in M13 (step), registered in the above-mentioned list (step), and the contents of the block are written in this area (step).

By the way, the document processing apparatus of this embodiment has a memory area for storing a list for each page. And
When the operator of the document processing apparatus designates a desired page and changes the content or adds a sentence, the search for the corresponding block can be performed more quickly.

FIG. 6 illustrates a part of the arrangement structure of the list of each page. In the example shown in FIG. 6, on the first page, a total of three lists of a first block to a third block 31-1 are registered. On the second page, a list of a total of two blocks 31-1 is registered.

FIG. 7 is for explaining the state of the list registration process. When the operator of the document processing apparatus specifies a desired page (step Y in FIG. 7), the CPU 11 shown in FIG. 1 checks whether or not a memory area for storing a list of the page exists (see FIG. 1). Steps). If there is (step; Y), the search and operation of the bitmap cache memory 13C for the corresponding block of the page are executed (step).

On the other hand, if there is no memory area for storing the list of the corresponding page (step; N), a memory area for storing the list allocated to the page is provided, and the bitmap cache of each block is provided. The memory 13C is registered in this memory area (step).

As described above, in the present embodiment, the list of the bitmap cache memory is registered in units of pages, so that when searching for blocks, it is possible to select the pages by page, thereby reducing the time required for searching for blocks and reducing the result. As a result, the display speed can be increased.

[Effects of the Invention] As described above, according to the present invention, a cache memory is provided in block units smaller than frame units and larger than character units. For this reason, the ratio of cache hits is larger than when a cache memory is provided in units of frames, and management is simpler than in the case of managing the presence / absence of hits in units of characters, and display is speeded up. Can be.

Further, in the present invention, scrolling of the display screen can be accelerated by displaying the contents of the bitmap cache memory at an appropriate place.

Further, in the present invention, since the contents of the document are managed in units of blocks, even if the displayed contents are moved or copied, the contents of the blocks affecting the movement may be rewritten and displayed. There is also an effect that management becomes easy.

[Brief description of the drawings]

1 is a block diagram showing an outline of a circuit configuration of a document processing apparatus, FIG. 2 is an explanatory diagram showing an example of a document structure,
FIG. 3 is a plan view showing an example of the contents of the document having the document structure shown in FIG. 2, FIG. 4 is a flow chart showing the state of control when displaying the document, and FIG. 5 is a bitmap cache. FIG. 6 is a flowchart illustrating a part of a list layout structure of each page, and FIG. 7 is a flowchart illustrating a state of a list registration process. 11 ... CPU, 13 ... RAM, 13-C ... bitmap cache memory, 15 ... magnetic disk, 22 ... display, 31 ... block, 34 ... page.

Claims (1)

(57) [Claims] 1. A bitmap display capable of displaying the contents of a document at least in page units, and a bitmap cache prepared for each block as a division unit of one page and storing image information of a corresponding block. A memory, block selecting means for selecting blocks whose contents have not changed when the contents of the document have changed in the page, and the bitmap cache corresponding to image information of the blocks whose contents have not changed An image information read control unit for reading from a memory and displaying the read information on the bit map display.