JPH05216454A - Display method for document and device to which the method is applied - Google Patents

Abstract

PURPOSE:To simply display and confirm an output result of document data for other devices by searching respectively desired fonts out of internal fonts of different devices such as a font of a display and a font of a printer and generating a compound font relating them each other. CONSTITUTION:This device is provided with the first searching means 12a which searches a font having a very similar feature to a feature of a font which is designated in document data out of a font contained in a device being used, and the second searching means 12b which searches a font having a very similar feature to a feature of a font which is designated in document data out of a font contained in the other device. A font generating means 12e has constitution which refers to a font of a different device, and generates the compound font in which fonts searched by the first and the second searching means 12a and 12b are related. Output control means 12g outputs data to a device being used referring to the compound font.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for displaying characters and an apparatus to which the method is applied. For example, an information processing apparatus for outputting document data such as a window system, an electronic publishing system, a word processor, etc. It can be used in the field. More particularly, the present invention relates to a document display method useful for displaying a print result on a display and confirming the print result in advance in such a field before printing, and an apparatus used for implementing the method.

[0002]

2. Description of the Related Art Conventionally, many application programs running on a window system require a printing function. For example, when printing an image displayed on a window or when printing a document in a fixed format. An easy way to implement the printing function is to send the bit image on the display to the printer. This method is disclosed in JP-A-3-
No. 102518, "CRT screen hard copy method"
The method is typified by the method described in.
However, this method has the disadvantage that the cost of communication is high because a large amount of figures and documents are sent to the printer as bit images, and the image quality is significantly degraded when the display resolution and the printer resolution are different. Has the drawback that Therefore, in order to reduce the communication cost between the computer and the printer and prevent the deterioration of the image quality, it is common to convert the figures and sentences displayed on the display into a page description language understood by the printer and send the conversion result to the printer. Has been done in. However,
When such a method is adopted, there is no guarantee that the font used on the display and the font inside the printer are the same. If the font corresponding to the specified display font does not exist in the printer, the printed result will be different from the image on the display. In such a case, it is required to have a function of confirming the print contents on the display before printing. On the other hand, when printing a pre-printed image that is not displayed on the display, the final printed image cannot be understood without actually drawing it on paper. In this case as well, as in the case of the hard copy, a function of confirming the print contents on the display before printing is required.

In response to these demands, a program called a previewer is generally provided for each page description language. The previewer has a function of reading a program generated in a page description language represented by Interpress or PostScript which is a programming language for controlling a page printer, and displaying the program on a display. It is a program. However, these are independent programs, and if the page description language is different, the operation method and function of the previewer will also be different. In rare cases, there are page description languages that do not have a previewer. If the number of printers to which an application program can be connected is increased, it is necessary to prepare a previewer having the same operation method for each page description language for the convenience of the user.

As a method of simultaneously realizing the printing function / preview function, there is a method of realizing a printer device which responds to a drawing request to a display device and outputs a page description language corresponding thereto. In this system, a display and a printer are defined as one device, and the output device of the program displayed on the display is switched to the printer device so that the output can be performed to the printer. A device is a functional unit that manages input / output to / from a medium. The medium is a display or recording medium such as paper in a printer or a magnetic tape or a magnetic disk in a magnetic storage device. Input / output management in the device is performed by a program called a device driver.

[0005]

As described above, in order to realize the preview function in the system capable of switching the device, the output destination of the program using the printer device is switched to the display device. do it. However, when the device is switched in this way, the fonts that can be used inside the device are different, so the output results of the display and the printer will be different in the printing / preview functions. Especially, due to the difference in the font width information, the text of both There was a problem that the line break position and the page break position would be different. In the past, in order to prevent a difference in output results due to such a device difference, it was common to prepare a font set with the same attribute information for the display and printer, but such an application
Since the font assumed by the printer is specified by the page description language, only the printer that interprets and executes the specified page description language can often be used, making it difficult to connect various page description languages and printers. It was

Therefore, the present invention is intended to solve the above-mentioned problems of the prior art. That is, the present invention provides a document display method capable of simply displaying on a display output of a device, a drawing output result of document data to another device having a font set different from that of the device. It is intended to be provided. Further, according to the present invention, in the system having the function of switching the drawing output destination of the document data by switching the device, the drawing output result of the document data to the other device can be easily displayed and confirmed on the display output of the certain device. It is also an object of the present invention to provide a document display device which is capable of achieving a simple structure without having to match the attributes of internal font sets of different devices. For example, to make it easy for an application program that outputs text to a printer to implement a "preview function" that allows you to check various page description languages and printer output results by displaying them on a window system. The purpose is.

[0007]

According to the document display method of the present invention, a font having a feature closest to the feature (for example, the character attribute of FIG. 6) of the font specified in the document data (for example, the sentence of FIG. 5) is selected. Fonts (14 and 15 in FIG. 1) of different devices (for example, displays and printers defined as devices) are searched for, and the fonts of the different devices obtained by the search are associated to generate a composite font. Document data is displayed by one of the different devices with reference to the composite font. Further, the document display device of the present invention has a system having a function of switching the drawing output destination of the document data (graphics) by switching the device, and the characteristics of the font specified in the document data (for example, the sentence of FIG. 5) ( (For example, the character attributes in Figure 6)
Is specified in the document data as the first searching means (12a in FIG. 1) for searching the font (14 in FIG. 1) of the device currently in use (16 in FIG. 1) for the font having the characteristic closest to The second search means (12b in FIG. 1) for searching the font (15 in FIG. 1) possessed by another device (for example, the printer) for the font having the characteristics closest to those of the different fonts Font generating means (12e and 12f in FIG. 1) having a reference structure and generating a composite font in which the fonts searched by the first and second searching means are associated with each other; Output control means (12g in FIG. 1) for outputting a character having the geometrical characteristics of the device to the device currently in use.

[0008]

According to the document display method of the present invention, a font having an attribute that closely matches a character attribute specified in the document data, for example, a character attribute as shown in FIG. Each font is searched and associated with each other to generate a composite font. The composite font is, for example, in a table format in which the storage addresses of the fonts obtained by the search are stored as a pair. Document data is displayed by one of the devices with reference to the compound font. For example, in the case of previewing on the display when the document data created by the document editing device is output to the printer, the display layout of the characters on the display is obtained using the size of the characters in the font attributes of the printer,
With the obtained arrangement, the character pattern of the display font can be displayed on the display, and the printed image of the document can be confirmed on the display.

Since the document display device of the present invention has a function of switching the drawing output destination of the document data by switching the device, it is possible to refer to a font of a different device,
It is possible to search. The first searching means uses the device currently in use (see FIG. 1) for the font feature (for example, the character attribute in FIG. 6) specified in the document data (for example, the sentence in FIG. 5).
16) and the font having the closest feature are selected. Similarly, the second
The searching means is selected from fonts of other devices (printers). The font generation means performs processing for associating the fonts selected as described above and forming a composite font. For example, the font generating means is configured as a table having a pair of font storage addresses, and the addresses of the fonts selected by the first and second searching means are paired and stored in the table for association. The output control means controls drawing output by referring to the associated font, that is, the composite font. For example, if the device currently in use is a display and the other device is a printer, the output control means is associated with the image when the document data is output to the printer. The character arrangement is calculated using the geometrical characteristics of the font of the printer among the above fonts, and the character pattern of the corresponding font of the display is used to perform display processing so as to generate a print image on the display. As described above, according to the present invention, the preview function can be easily realized.

【Example】

(First Embodiment) Here, an example in which the present invention is applied to a document editing application operating on a window system will be described. This application program edits a sentence on a display and outputs the edited result to a printer. Furthermore, this application shall be able to specify the type of character when editing a sentence. For example, if the character string in the specified range is "character size is 1
You can specify the type of character in "2-point italic". In the window system, before displaying characters on a window, a procedure of specifying data called font to specify the type of character is involved.

A font is data used to obtain a character image from a character code in a window system. At the same time, the font is provided with various information such as the height and depth from the font reference line and a table for obtaining the width of each character. For example, in order to obtain the character width of the character "A", the character code "65" is used as an index to look up the character width table. To determine the position of line breaks in sentence shaping, the partial character string that fits on one line is calculated by comparing the sum of the individual character widths of the given character string and the specified length of one line. To be done. The edited text is divided into line units and page units before being output to the printer, and finally converted into a page description language and output to the printer. At this time, the text is formatted based on the attributes of the font inside the printer, such as the height, depth, and width of each character. Therefore, even if an attempt is made to format the text on the window based on the font of the display, the appearance of the text output from the printer will naturally be different.

To completely solve this problem, it is necessary that the fonts used in both the display and the printer have the same attribute, and that the font search in both display media selects the font having the same attribute. I have to guarantee. However, in any combination of window systems and printers, it cannot generally be guaranteed that both have the same font set. Therefore, it is assumed that the document editing application described above can confirm (preview) the output result on the window before actually outputting the sentence to the printer. The minimum required function in the preview is that the display position of the character on the paper is reproduced on the window. So to solve this problem,
It can be seen that the font used in the window may be any font that has the attributes (geometrical attributes) of the font of the target printer and that refers to the display font for display.

If the window system can output the image on the window to the printer by switching the device representing the display destination, the available font can be obtained from the device representing the printer. However, if the window system cannot output the image on the window to the printer simply by switching the display destination to the printer device, the application program must convert the image on the window into the page description language. In the latter case, in order to make the font attributes inside the printer available to applications on the window system, the application reads an external file (font metrics file) that describes the font attributes inside the printer and It is necessary to convert the format into a data structure that can be recognized by the application and can be handled uniformly by all printers (see FIG. 8). The printer font attributes taken into the application after the format conversion can be uniformly handled in the application. In this way, it is possible to obtain the data structure of the font inside the printer regardless of the type of window system. Here, the data structure representing the font inside the printer is called a print font for the sake of description.

In order to select the font having the attribute designated by the application from the inside of the device, it is necessary to select one appropriate font from various kinds of fonts available inside the device. This font search is to compare the font attributes existing inside the device with the font attributes specified by the application and select the font with the closest attributes (see FIG. 10). On this occasion,
For all fonts, evaluation calculation is performed with the font attributes specified by the application so that they can be digitized. In this way, among the evaluation values calculated from all the device fonts, the font having the highest evaluation value is the desired font.

The font for preview is a composite font that refers to both the display font and the print font obtained as a result of the font search from the display and the printer, respectively, and the print font is used for the operation for obtaining the geometric attribute. And is configured as a font having a characteristic of referring to a display font when displayed on a display (see FIG. 9).
When the font for this preview is set on the window system, the display font is used for the characters displayed as the font, and the print font is used for attributes such as character width.

The preview font obtained as described above has the same line division as the result output to the printer,
You should be able to reproduce the paginated image in the window. The configuration and operation of the device having the character display unit for displaying the font for the preview will be described more specifically with reference to the drawings.

FIG. 1 is a functional block diagram showing a document edit processing device constituted by the functions of a document edit application program running on a window system. This apparatus includes a document edit processing unit 11 having a document editing function, and a document preview processing unit 1 for checking the outline of a print image on a display when printing a document.
2, a print processing unit 13 that performs a process for printing, and a font storage unit 1 that stores the font data of the display.
4, a font storage unit 15 that stores font data of the printer, and a display 16 that performs a display necessary for document editing processing.

In this document editing apparatus, the characteristic part of the present invention is the document preview processing section 12, and the other parts can be constructed by conventional techniques. The document preview processing device 12 includes a font search unit 12a for searching a display font, a font search unit 12b for searching a printer font, evaluation lists 12c and 12d for holding font evaluation results, and a searched printer font. A font combining unit 12e for associating a display font with a display, a composite font storage unit 12f for storing a composite font, and a process for displaying characters on the display 16 by referring to the two associated fonts found. A display control unit 12g and an attribute extraction unit 12k for obtaining a specified attribute and a partial character string having the same attribute in the created and edited text are provided. The font search units 12a and 12b are the font comparison units 12a1 and 12a.
b1, font evaluation units 12a2 and 12b2, and font selection units 12a3 and 12b3. One of these font search units is provided as a common search unit,
You may comprise so that the font for comparison may be switched. The font comparison unit 12a1 sequentially compares the font attributes of the designation (request) given from the document edit processing unit 11 with the data of all the fonts stored in the font storage unit 14. The font comparison unit 12b1 basically has the same function as the font comparison unit 12a1 except that the comparison target to be compared with the designated font attribute is the data in the font storage unit 15 of the printer. The font evaluation unit 12a2 collects the comparison results of the font comparison unit for each designated attribute of the character font, and holds it in the font evaluation list. The font evaluation unit 12b2 also has substantially the same function as the font evaluation unit 12a2. The font selection unit 12a3 holds the font evaluation list 12 that holds the evaluation results of the font evaluation unit 12a2.
Based on the data of c, the font that most matches the specified font attribute is selected. Font selection section 12
b2 also has substantially the same function as the font selection unit 12a2. The font compositing unit 12e associates the storage addresses of the fonts searched by the font searching unit 12a of each display with the storage addresses of the fonts searched by the font searching unit 12b of the printer, and creates a composite font table. It has a function of storing in the composite font storage unit 12f. The display control unit 12g has a function of performing a display process such as calculating a display position of a character or a character string based on the printer font attribute of the composite font data and displaying the character or character string in the character pattern of the bitmap of the display font. ..

FIG. 2 is a flow chart showing the overall operation of this embodiment. The document editing application on the window system is activated, and the function of the document editing processing section 11 is started (step 21). In the document edit processing unit 11,
When outputting the edited document, the user can select whether to print it or preview it, and it is determined which has been selected (step 22). When print is selected, print processing is performed (step 23), and when preview is selected, processing for previewing the document is performed (step 2).
4). When the document preview process or print process is completed,
The document edit processing unit 11 determines whether the end of the document edit processing is instructed (step 25), and if the end instruction is given, the processing of the document edit application is ended,
Otherwise, the document editing process is continued.

FIG. 3 is a flowchart showing the document preview process of step 24 in FIG. When the preview process is selected and the edited text with the specified character attribute is given from the document editing processing unit 11, a window for preview is opened (step 32) and the text is displayed in the window with the specified character attribute. The processing for performing is performed (step 33). When the end of the preview process is instructed (step 34), the preview window is closed (step 35).

FIG. 4 shows a flow for displaying the text in step 33 in FIG. The edited sentence is given (step 41), and the sentence display loop starts (step 42). This loop loops while displaying all the strings that fit in the window. When the loop starts, the attribute extraction unit 12k scans the input edited sentence and acquires the following information (step 4).
3). Requested font attribute Partial character string with the same attribute The partial character string with the same attribute is obtained because in the present embodiment, display processing such as calculation of the display position is performed for each character string. FIG. 5 shows an example of a sentence, and this sentence has a sentence structure composed of a plurality of partial character strings having character attributes as shown in FIG. In the present embodiment, the character attributes of the text do not directly specify the name of the font, but the attributes for selecting the font. This is because the font name may be unique depending on the device, and if the font name is specified and selected, it becomes impossible to find a font having similar characteristics. When the above-mentioned information and are obtained, the composite font is generated and displayed based on the information (step 44).

FIG. 7 shows the flow of the composite font generation and display processing of step 44 in FIG. 4. In this flow, when the attributes of the partial character string and its required font are given (step 71), A composite font is generated (step 72), and characters are displayed using the generated font (step 73).

FIG. 9 is a flow chart showing details of the composite font generation step 72 in FIG. When the attribute of the required font is given (step 91), the font of the display is searched based on the attribute (step 92). Determine the result of the search (step 9
3) If no font is found, error processing is performed (step 94). If a font is found, then a printer font search is performed (step 95). In addition, the result of the search is determined (step 96),
If the font is not found, error processing is performed (step 97). If the font is found, the display font and the print font are associated as one composite font (step 98), and the composite font is output (step 98). 99).

The same algorithm is used to search the display font and the printer font. FIG. 10 shows the flow of the font search. As described above, the attribute of the required font is the sentence analysis unit 12
When given from k (step 101), the evaluation lists 12c and 12d are first initialized (step 102).
Next, font evaluation and registration in the evaluation list are performed (steps 103 to 105). The font of the device (display or printer) and the font request data are compared, and the evaluation value and font pair are registered in the evaluation list. At this time, it is assumed that the font inside the device has already been initialized. It should be noted that FIG. 8 shows a procedure for obtaining font initialization from a font metrics file by format conversion in the case of a printer. When the registration to the evaluation list is completed, the evaluation list is sorted based on the evaluation value and the font with the highest evaluation is selected. If there is only a font with an evaluation of 0, an error flag is returned (step 106). By such search processing, a font or an error flag is obtained (step 107).

The details of the above font evaluation and registration processing in the evaluation list are shown in FIG. The evaluation list, the attributes of the requested font, and the actual font are given as data (step 111). Evaluation list 12
Initialize the evaluation values held by c and 12d to zero (step 112), and set the font attributes (size, bold, italic, proportional, decorative characters, character encoding, etc.) from the font storage units 14 and 15 to the actual font name. (Step 113). Next, the attributes of the requested font and the actual font attributes are compared by the font comparison units 12a1 and 12b1, and if they match, the evaluation value is increased. This is all done for the attributes that characterize the font (size, bold, italic, proportional, decorative characters, character encoding, etc.) (steps 114-116). That is, the attribute size of the requested font is compared with the actual font size, and if they are the same, 1 is added to the evaluation value (step 114). Next, the bold attribute of the requested font and the bold attribute of the actual font are compared, and if they are the same, 1 is added to the evaluation value (step 115). The italic attribute of the requested font attribute and the italic attribute of the actual font are compared, and if they are the same, 1 is added to the evaluation value (step 116). Similarly, proportional values, decorative characters, character encodings, etc. are evaluated and evaluation values are obtained. Then, the set of the evaluation value and the actual font is registered in the font evaluation lists 12c and 12d (step 117). It should be noted that in the above description, an evaluation value of 1 is added to any attribute if they match as a result of comparison, but in reality, more accurate evaluation can be obtained by weighting according to the importance of the attribute.

The association between the display font and the print font (step 98 in FIG. 9) at the time of generating the composite font is performed by the processing flow in FIG. That is, the print font and the display font obtained by the search are given (step 121), and the area of the composite font storage unit 12f for storing the composite font is allocated (step 122). Composite fonts are generated with reference to both display fonts and print fonts. That is, the process of associating the display font with the composite font is performed (step 12).
Along with 3), the process of associating the print font with the composite font is performed (step 124). Specifically, the composite font data includes the stored address of the display font selected by the font selection unit 12a3 based on the font evaluation list 12c and the font evaluation list 12c.
It is configured as a table in which the stored addresses of the print fonts selected by the font selection unit 12b3 based on d are associated with each other, and are stored in the composite font storage unit 12f.

Character display by the composite font obtained as described above is performed according to the flow shown in FIG. That is, the character display unit 12g calculates the display position of the partial character string in the composite font (step 81).
Remember the previous display position of the character string as the current position,
Add the length of the substring to it. If the current position exceeds the line length, a line break is performed. Display processing of the partial character string by the compound font is performed (step 132), and it is displayed in the window (step 133). Character display using a composite font uses a character pattern (bitmap) of the display font, and calculation of the display position uses geometric attributes such as the character width of the character of the print font.
Therefore, the same line-divided and page-divided image as the result output to the printer can be reproduced on the window.

(Second Embodiment) In the second embodiment, the present invention is implemented by Smalltal which is an object-oriented system.
k system: Objectworks for Sma
It is applied to lltalk Release 4 (trademark of Park Place System Co., USA). That is, in this embodiment, a printing function is added to the Smalltalk system and a preview can be performed. Smalltalk is
Being an object-oriented language, the following explanation is explained by exchanging messages between multiple objects, but it is easy to replace it with structures / records and functions / procedures of other procedural languages. ..

Characters in the Smalltalk system
Display This section describes the basic mechanism of displaying graphics in a window in the Smalltalk system. In Smalltalk systems, all output to the display is GraphicsConte
It is done by sending a message to the xt object. The GraphicsContext object holds, as an internal state, the following mediums to be displayed and the following parameters used for drawing. Display media Clipping information Information such as line thickness / shape Font color Tiling information Coordinate conversion information

When a message is sent to the GraphicsContext object, it does different things depending on the type of display media. For example, consider the case where a message with the content "Draw a line from one coordinate to another coordinate" is sent to the Graphics Context. In this example, if the display media is a window, it will use the coordinate system inside the window and the Graphics
A process of connecting a line between two coordinates obtained according to the coordinate conversion information inside the context based on the line thickness color information stored inside the GraphicsContext is performed. The process of drawing a line is actually a Grap
This is implemented by calling the line drawing function provided by the windows system provided by hicsContext. (1) aGraphicsContext: = a
Windows graphics Context. (2) aGraphicsContext li
neWidth: 10. (3) aGraphicsContext pa
int: ColorValue gray. (4) aGraphicsContext di
sprayLineFrom: 100 @ 100 to:
200 @ 200.

The drawing of characters can be considered in the same manner, but the point of referring to the font in the window system is different. In other words, first find one font that can be used inside the device, and select it
It is necessary to set it in csContext and then draw a character. The font obtained as a result of the search is
It is a font object that refers to an identifier that can specify a font in the device so that the fonts in the device can be handled as objects in the system in a unified manner. The font object can specifically meet the requirements such as height, depth and width of individual characters. The structure of the font object for the display is shown below.
The font object for this display is Dev
Called iceFont. Address of the font in the window system Height from the baseline of the font Depth from the baseline of the font Width table of all characters in the font Font name Table to find index from character code to character width table

The font object is realized as a font object that has a handle of the address of the font managed in the window system.
The drawing function of the window system refers to this when drawing characters on the window. Information such as the height, depth, and width of the device font can be obtained from the window system font by a drawing function, and thus they are held as internal variables of the font object.
These internal variables can be obtained by sending a message to the font object. By obtaining the attributes of these fonts, the application can be used for text formatting, especially for page layout processing such as line division and page division. In other words, the application refers to the attributes of the font object, decomposes the sentence into substrings according to places such as spaces and line breaks, selects the font for these substrings, and displays them. Determines where on the media to place it. In this way, when it is determined in which font and where to draw the partial character string, Graphic
Set the font to sContext and send a character draw message to it. The selected font is device-dependent because it is selected inside the device. For example, if the application is Helvetic
If you request a 12-point font for a, it may exist in the device of one window system but not in another. The Smalltalk system has been ported to various platforms (environments), so it is devised for device independence. In other words, since the font itself has a device-dependent characteristic, in Smalltalk, the application does not directly specify the font by the font name, but indirectly by using the font characteristics, the characteristics of the font specified from inside the device by the font characteristics. Search for fonts close to. The FontDescription object is an object that stores the font characteristics required by the application to do this. The FontDescription object holds the requested font size, bold attribute, italic attribute, and the like as internal states, and uses them as parameters of a message for searching for a font close to the request from inside the device. The following four lines are Smallta
This is a code for font search in lk. This code searches the device for a 12-point size font, sets it in aGraphicsContext, and executes character drawing.

(1) aFontDescription
ion: = FontDescription new
pixelSize: 12; italic: true. (2) font: = aGraphicsCont
ext findFont: aFontDescrip
section. (3) aGraphicsContext fo
nt: font. (4) aGraphicsContext di
sprayString: 'Smalltalk' a
t: 100 @ 100.

In the first line, a FontDescription object representing an italic font with a size of 12 points is generated. The second line findFont: message is a message for font search.
When you send a font search message to aGraphicsContext, it will be sent to aGraphicsContext.
It is transferred to the display medium referred to by ext and transferred to the device driver. The device driver selects the font closest to the request from the fonts available in the device and returns it. In the third line, set the font object to GraphicsContext,
In the fourth line, draw a character string at the position of coordinates (100, 100). The font search is to compare the attribute of the device font inside the device with the attribute of FontDescription and select the device font having the closest attribute. At this time, all the device fonts are converted into FontDescription having the same attributes as those, and the FontDescr requested by the application is converted.
Font the distance between the option and those attributes
Enables digitization by operations between Descriptions. Among the numerical values calculated from all device fonts, the device font showing the smallest value is the font requested.

Device expansion of the Smalltalk system
Zhang Here, a method of this embodiment for expanding the graphics display of the Smalltalk system so as to correspond to the output to the printer will be described. Graphics
The display medium referred to by Context is extended so that not only the medium on the display such as a window but also a printable medium can be used. In order to achieve this, when a drawing request message is sent to the GraphicsContext, the message is transferred to the display medium. That is, how the drawing request message is actually displayed is delegated to the media. Therefore, the output destination of the drawing request can be changed by creating a display medium for printing and changing the display medium of Graphics Context to this. Conventional Small
In the present embodiment, the display medium on the display such as the window in alk is Display Surfa.
It is an object called ce. DisplaySur
face is an object having a size as a display destination. In this embodiment, GraphicsCont
Display media of ext is DisplaySurface
If so, the drawing is performed on the window, but the method of realizing it is different from the conventional method. In other words, GraphicsCon
The drawing request message sent to the text is not executed by the GraphicsContext as in the conventional case but is transferred to the DisplaySurface, and the drawing function of the window system is displayed by the DisplaySurfa.
It is executed after being transferred to ce.

On the other hand, the print-only display medium is an object called PrintSurface in this embodiment. PrintSurface is a Disp
It is an object having the same protocol as laySurface and represents virtual paper. Print
Surface has a printer driver as an internal state. The printer driver performs processing such as conversion into a page description language for interpreting and executing a drawing request and writing to an external file. A different object is prepared for each page description language in the printer driver. By setting this object in PrintSurface, a drawing request to GraphicsContext can be converted into an arbitrary page description language.

FIG. 14 shows the above-described Graphic.
It shows the relationship between sContext and devices.
The actual drawing is done not by the display medium but by the device driver referenced by the display medium. Therefore, the application is not limited to the details of the device, and only the display medium is selected. Will be able to describe. For example, the message "Draw a line from one coordinate to another" sent to Graphics Context is first transferred to the display media, then to the device driver, and finally the device driver to the display media. Perform the corresponding process. If the display device is PrintSurface, this message is translated into a line drawing program in a particular page description language, but the application programmer need not know any details of the page description language.

The drawing of characters on PrintSurface can be considered in the same manner as in the case of DisplaySurface, but it should be noted that the font object depends on the display medium. That is, since the font searched for from the DisplaySurface represents the font inside the window system, it cannot be expressed as the same font object because it has a different property from the object searched from the PrintSurface. PrintSu
PrintFo the font object for rface
Implemented separately as nt. PrintFont is De
It has the same message protocol as ViceFont, but the internal state is a font object depending on the printer and page description language.

In the case of PrintFont, the font object is a font object having an identifier that can uniquely identify the font defined by the page description language of the printer. The printer driver will refer to this when converting it into a command string in the page description language for character drawing on the printer. Information such as the height, depth, and width of the print font can be obtained from the font metric file (font information in the page description language in an external file), so it is held as an internal variable of the font object. .. These internal variables can be obtained by sending a message to the font object. PrintFon
Since t can reply to the same message as DeviceFont, an application whose display destination is a window can be output to the printer without changing itself.

Introduction of User Coordinate System Normally, in the page description language, the coordinate system used by the programmer is called the user coordinate system, and the unique coordinate system defined on the device is called the device coordinate system.
By freely changing the coordinate conversion matrix from the user coordinate system to the device coordinate system, the programmer can draw the figure defined on the user coordinate system in the device coordinate system in any size / orientation. By introducing such a user / device coordinate transformation into Smalltalk, the display surface and Pr
The layout of the graphic on the intSurface and the unit system can be set by changing the user coordinate system. This coordinate conversion matrix is Sm in a natural form.
To introduce it into alltalk, it's Graphi
It will be held as an internal variable of the csContext object.

The display medium is Display Surfa
In the case of ce, the coordinates passed as a parameter of the message to GraphicsContext are Graph.
A coordinate conversion matrix in icsContext converts the device coordinates into device coordinates, and the message to which the converted parameters are passed is transferred to the DisplaySurface. For example, if the coordinates transformation matrix of GraphicsContext has 2 × 2 scaling, the message “Draw a line from coordinates (100,100) to coordinates (200,200)” sent to GraphicsContext will read “Coordinates (200, 200, 200)”. 20
Draw a line from 0) to coordinates (400,400) "
will be transferred to ce.

On the other hand, the display medium is PrintSurf.
In the case of ace, since the print device has the coordinate conversion function, the coordinate conversion matrix is passed to the print device as a parameter of the message and the user / device conversion is left to the printer without performing the coordinate conversion in GraphicsContext.

In addition to the user / device coordinates, the character coordinate system is involved in the display of characters. The character coordinate system is a coordinate system in which characters are defined. By performing coordinate conversion from the character coordinate system to the user coordinate system, characters can be defined in any size / direction. The shape of a character on the device coordinate system is defined by a composite matrix of a coordinate conversion matrix from the character coordinate system to the user coordinate system and a coordinate conversion matrix from the user coordinate system to the device coordinate system. Therefore, this character coordinate system is based on FontDescription
It is appropriate that n has an internal state. Therefore,
When searching the DeviceFont, the size of the font to be searched is influenced by the composite matrix of the Font / description character / user coordinate conversion matrix and the GraphicsContext user / device coordinate conversion matrix passed as a parameter of the font search. Because DeviceFo
Since nt is defined in the device coordinate system, it is necessary to generate the font defined in the user coordinate system according to the coordinate conversion matrix. For example, if the font size requested in the user coordinate system is 12 points, G
Assuming that the graphicsContext user / device coordinate transformation matrix has a 2x2 scaling, the font size required in the device coordinate system must actually be 24 point size. However, at the same time, since geometrical attributes such as height, depth and width must be defined in the user coordinate system, those geometrical attributes must all be reduced to 1/2 size.

In order to generate such a font on the user coordinate system, a font object that returns the value of the geometric attribute on the user coordinate system may be defined. Description of this font object Transforma
Call it bleFont. TransformableF
ont is the actual font inside the device (called the base font) and G when the base font is searched.
Reference the coordinate transformation matrix of the graphicsContext. This coordinate conversion matrix is used to convert the value defined on the device coordinate into the value on the user coordinate system. In addition, if Transformable
While the Font is in use, GraphicsCo
FontDescription used for searching the base font so that the font inside the new device can be searched again when the coordinate conversion matrix of the text is changed.
Holds ion. Graphics Context
The inspection whether the coordinate transformation matrix of t has been changed is
Character display message is Graphics Context
TransformableFont every time it is sent to
Coordinate transformation matrix and GraphicsC at that time
This is done by comparing the coordinate transformation matrices of text. If the comparison fails, the font is searched again.

Base font Graphi when the base font is searched
csContext coordinate transformation matrix FontDe when the base font is searched
scriptTransformableFon
t has the same message protocol as the base font, so DeviceFont and Print
Using it instead of Font works perfectly.

Implementation of Previewer Font Here, problems and solutions when switching the display media will be described. As shown in FIG. 14, Gra
It was confirmed that the output to the display can be easily switched to the printer and vice versa by switching the display medium of the picsContext. However, when switching the display media in this way,
Since the fonts that can be used on the display media are different, the output results of the display and the printer will be different in the printing / preview functions. Especially, the line feed position and the page break position of both sentences will be different due to the difference in the font width information. There is a problem. (1) aFontDescription: =
Font Description new pixel
Size: 40. (2) font: = aGraphicsCon
text findFont: aFontDescr
option. (3) aGraphicsContext fon
t: font. (4) aGraphicsContext dis
playString: 'Smalltalk' a
t: 100 @ 100.

For example, the display medium is DisplayS
In the case of urface, the font selected in this program is 40-point Helvetica, and the font selected when this display medium is switched to PrintSurface is 20-point Hel.
There may be cases where fonts of different sizes are selected, such as "vetica". Or 40 for one
Fonts of different families may be selected, such as Helvetica for points and Times for 40 points on the other. As in these examples, Disp
If the font is different between laySurface and PrintSurface, the height, depth, width, etc. of each character will naturally be different, and if the text is formatted based on the attributes of these fonts, the final appearance of the text will be displayed. Will of course be different. To completely solve this problem, Di
spraySurface and PrintSurface
It must be ensured that the set of font objects used by both have the same attributes, and that font objects with the same attributes are selected in the font search for both display media. However, it is not realistic that both have the same font set in any combination of window systems and printers.

The minimum required function in the preview is that the display position of the character on the paper is reproduced on the window. So to solve this problem,
It will be understood that the font object used in the preview window may be any object that has the geometric attribute of PrintFont of the target printer and that refers to DeviceFont.
In other words, the font for the previewer is Device
It is a compound object that refers to both eFont and PrintFont. It should be configured as an object that has characteristics such that PrintFont is referenced for a message requesting a geometric attribute and DeviceFont is referenced when actually displaying. Recognize.
A font having such a structure that refers to the fonts of two devices will be referred to as a previewer font for the sake of description.

The font for preview is preferably used on a specific display device. So, define a window for preview and call it PreviewViewSur.
I will call it face. Preview Surfa
ce is a display device that refers to both the window device driver and the printer device driver. The previewer font is this Preview Surfac
A font object obtained as a result of the search when a font search is performed on e. The procedure for generating this previewer font is as follows. (1) Generate Preview Surface. (2) From Preview Surface to Gra
Get the picsContext. (3) Search the display device for a font with the specified attribute. (3.1) Obtain Preview Surface, which is a display medium, from Graphics Context. (3.2) Transfer the font search message to PreviewSurface. (3.3) A font having a specified attribute is searched for from the display device referenced by PreviewSurface. (4) A font having an attribute close to the font obtained as a result of the above search is searched for from the print device. (4.1) Obtain the FontDescription used for the font search of the display device. (4.2) This FontDescription
A font search is performed from the print device referred to by Preview Surface based on the above. (4.3) Convert each of the first font and the second font into FontDescription. (4.4) Two Font Descriptio
The difference in n is quantified and the distance (closeness) between these attributes is calculated. (4.5) If the distance is greater than the threshold,
A font that always outputs only a substitute character for a specific symbol or graphic is generated regardless of what character code these attributes are given. (5) The two fonts obtained as a result are combined into one previewer font.

In the above procedure, the previewer font generated is the device displayed as a font.
Font's one is used, and geometric characteristics are PrintF
Use the one from ont. The following shows which font attributes each internal state of the previewer font uses. Address of the font in the window system (D
height from font reference line (PrintFon)
t) Depth from font reference line (PrintFon
t) Width table of all characters included in the font (PrintFont) Font name (DeviceFont) Table for obtaining an index from the character code to the character width table (PrintFont)

[0051]

According to the document display method of the present invention, on the display output of a device, the drawing output result of document data to another device having a font set different from the font set of the device can be simply displayed. Can be displayed in. According to the document display device of the present invention, in the system having the function of switching the drawing output destination of the document data by switching the device, the internal fonts of different devices, for example, the font of the display and the font of the printer, are respectively searched, and they are searched. Since the compound font is generated in association with each other, the output result of the document data to another device can be easily displayed and confirmed on the display output of a certain device. For example, it is possible to easily realize a preview function in which an application program that outputs a sentence to a printer displays various page description languages and a printer output result on a window system for confirmation. In addition, in the related art, in order to obtain the same display result when document data is displayed on one device, the attributes of internal font sets of different devices are matched. However, according to the document display device of the present invention,
It is easy to configure the system as there is no need to match them.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment.

FIG. 2 is a flowchart showing an outline of overall processing of an example.

FIG. 3 is a flowchart showing a document preview process of step 24 in FIG.

FIG. 4 shows a flow for displaying a sentence in step 33 in FIG.

FIG. 5 shows a text example of the present embodiment.

6 is a diagram showing an example of a sentence structure of the example sentence of FIG.

7 is a diagram showing a flow of generation and display processing of a composite font in step 44 in FIG.

FIG. 8 is a diagram showing a procedure for obtaining font initialization from a font metrics file by format conversion in the case of a printer.

9 is a composite font generation step 7 in FIG. 7.
It is a flowchart which shows the detail of 2.

FIG. 10 is a diagram showing a flow of font search.

FIG. 11 is a diagram showing a flow of processing of font evaluation and registration in an evaluation list.

FIG. 12 is a diagram showing a processing flow of associating a display font and a print font when generating a composite font.

FIG. 13 is a diagram showing a flow of character display by a composite font.

FIG. 14 is a diagram showing a relationship between Graphics Context and a device.

[Explanation of symbols]

11 ... Document edit processing unit, 12 ... Document preview processing unit,
12a ... Display font searching unit, 12b ... Printer font searching unit, 12c, 12d ... Font evaluation list, 12e ... Font compounding unit, 12f ... Compound font storage unit, 12g ... Display control unit, 12k ... Attribute extracting unit , 13 ... Print processing unit, 14 ... Display font storage unit, 15 Printer font storage unit, 16 ... Display.

Claims (2)

[Claims] 1. A compound font is searched for fonts having characteristics closest to the font characteristics specified in document data from fonts of different devices, and the fonts of different devices obtained by the search are associated to form a composite font. A method for displaying a document, wherein the document data is generated and displayed on one of the different devices by referring to the composite font. 2. A system having a function of switching a drawing output destination of document data by switching a device, and a font having a feature closest to a feature of a font specified in the document data, in a device currently in use. First search means for searching from a font, second search means for searching for a font having characteristics closest to the characteristics of the font specified in the document data from a font of another device, and reference to a font of a different device Has a structure to
And a font generation unit that generates a compound font in which the fonts searched by the second searching unit are associated with each other, and a device that is currently using a character having geometrical characteristics of the other device with reference to the compound font. A document display device, comprising: