Simtel MSDOS 1992 June

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Text File | 1988-06-20 | 23.7 KB | 450 lines

FONTVIEW Documentation (Version 3.0) June 19, 1988 FONTVIEW is Copyright (c) 1988 by S.H. Moody & Associates, Inc. 1810 Fair Oaks Ave. South Pasadena, CA 91030 All Rights Reserved. FONTVIEW reads HP-specification LaserJet downloadable PORTRAIT or LANDSCAPE orientation font files and displays the magnified characters in the file on your EGA screen in increasing ASCII order. You must have an EGA display card installed in your computer for FONTVIEW to function. FONTVIEW automatically magnifies the font character images as much as possible while retaining the font's original horizontal and vertical proportions on the screen. User options include manually setting X and Y magnifications, setting the display time of each character before proceeding to the next character, and overriding the default grid-like display to instead display characters as solid figures. FONTVIEW and the accompanying FNTCLEAN are not free, but Shareware. If you find FONTVIEW or FNTCLEAN useful, you are requested to forward $17.00 to the above address to register your copy and receive two useful additional font programs (see REGISTRATION, below). USING FONTVIEW The syntax for running FONTVIEW is: FONTVIEW fontfile.ext [/S] [/Mx,y] Where the parameters in brackets are optional and may be omitted from the command line. "fontfile.ext" is the complete name of the font file you wish to view. DOS paths are supported if you are using DOS 2.0 or higher. /S tells FONTVIEW to display solid characters on the screen. The default for the program ( no "/S") is to display characters using a dot plot shape which includes a background-colored line on the top and right sides to allow you to clearly distinguish the individual dots forming the character. /Mx,y allows you to manually set the screen magnification in the X and Y directions instead of having FONTVIEW determine these values. The values to substitute for "x" and "y" specify the amount of magnification to use in the direction indicated. For example, /M9,6 tells FONTVIEW to display 9 dots horizontally on the screen for each horizontal dot in the font file, and 6 dots vertically for each vertical dot in the font file. After FONTVIEW displays a character, pressing any key causes the program to proceed to the next character. All characters are displayed in increasing ASCII order, regardless of their order in the font file. If you want to view all the characters in a file without manual intervention, you can hit any of the numbers between 0 and 9 and FONTVIEW will display a character, pause for the number of seconds you have input, and proceed to the next character. To shut this "auto-display" feature off once it has begun, merely hit any non- numerical character and FONTVIEW will again await a keystroke before proceeding to the next character. To change the amount of delay between the display of characters, just press a different numerical value and the program will use the new value after the next character display. To view a particular character in a font file, press "E" or "e" (for ENTER Character) and at the lower left corner of the screen the program will prompt you to enter the character from the keyboard. To view characters not on the keyboard, press and hold down the ALT key while entering the character's ASCII number from the NUMERIC KEYPAD, then release the ALT key. The screen will display the appropriate character. Following the display of the character, FONTVIEW will resume its display sequence order beginning with the character with the next higher ASCII number. If you change your mind after pressing "E", merely hit RETURN without entering a number and FONTVIEW will resume its display sequence from where it left off. If you enter a character or ASCII number of a character which is not in the font file, FONTVIEW will beep, display "NOT THERE. TRY AGAIN" for two seconds then prompt you to "Enter Character" again, all in the lower left hand corner of the screen. To exit FONTVIEW, hit the Escape key and you will exit after the next character has been displayed. Upon exiting, FONTVIEW will display the LaserJet escape code sequence to use to call the font into use after it has been downloaded. To check that FONTVIEW is compatible with your hardware, I suggest you first try FONTVIEW on a file which is known to be specified correctly. The file DEMO.SF2 (included in this archive) is a twelve character (6 portrait, 6 landscape) font file which will establish that your hardware is suitable. Type FONTVIEW DEMO.SF2 to display the 6 characters ("A", "B", "W", "p", "x" and "y"), first in landscape, then in portrait orientation. DEMO.SF2 is not a valid LaserJet font file since it contains a mixture of portrait and landscape characters. The landscape characters are stored in the file as ASCII characters 1-6 and so appear first in the display sequence. THE FONTVIEW DISPLAY SCREEN The display window is divided into two elements: a text portion along the left side, and a graphics window occupying the rest of the screen. THE GRAPHICS WINDOW Inside the graphics window you'll see a magenta rectangle within which the magnified character is displayed. This rectangle, or cell, displays the boundaries within which all characters in the font normally fit. Also shown within this font cell are two horizontal lines. The lower, solid line is the baseline which is the bottom row of dots for most characters. For example, the bottom of the "A", "B", and "x" of DEMO.SF2 coincide with the baseline. Descenders fall below this baseline. In many fonts (particularly the larger fonts) the bottom of the "C", "G", "O" and others extend up to a few dots below the baseline to improve their attractiveness. The second, dotted line shown in the cell is the "x-height" line. The top of the lower case "x" should coincide with the x-height line while the bottom of the letter coincides with the baseline. The x-height is generally the top of lower-case characters except for those with ascenders ("b", "d", etc.), however, again in many typefaces the top of the "c" and "o" and the top of the loops in "b", "d", "p" and others often extend 1-3 dots above the x-height line to improve their appearance. Finally, and most important, the magnified character is dis- played. Characters are placed within the character cell using the "left offset" value stored in the character header unless the left offset value is 0 or negative. THE TEXT WINDOW The left, text portion of the screen presents data found in the font and character headers. HP-specification laserjet soft fonts are comprised of three types of data: first is the FONT header, which contains information for the font as a whole; second are CHARACTER headers (one for each character) which contain width, height, and spacing information for each character; and finally, the bit image data for the character. FONT DATA The top portion of the text portion of the screen displays a portion of the font header information. This information is displayed once for each font, and thus will not change as you view each character. The first line shows the DOS filename of the font which you entered on the command line. The second line shows the name of the font if it is included in the header. Often, particularly with shareware fonts, this information is not included so nothing will appear after "NAME:" on this line. The third line shows the typeface (Times Roman, Helvetica, Optima, Garamond, etc.). This information is decoded from the font header. HP has assigned codes for over 20 typefaces, which I have incorporated into FONTVIEW. Nonetheless, many soft fonts put a code value in the header which FONTVIEW does not recognize. in this case, "UNKNOWN" will appear on this line. The fourth line Shows the orientation of the font, either "Portrait" or "Landscape". The fifth line shows the spacing of the font and should be either "Fixed", or "Proportional". The sixth line shows the symbol set of the font, which identifies which character set the font is using (USASCII, PC-8, HP Roman Extensions, etc.). Again, HP has assigned codes for over 30 such sets, which are included in FONTVIEW, but if the font maker uses a code which is not recognized, the word "UNKNOWN" will appear on this line. The seventh line, "Points", shows the height of the font, in HP points. HP fonts are defined based on 72 points per inch, as opposed to the standard printer's point which is 1/12 of a Pica or 72.27 per inch. The body size of a font, in points, is the vertical distance measured from the bottom of a descender, such as the stem of a "p" to the top of an ascender, such as the stem of a "b". To convert points to 300 dots/inch dots, multiply by 4.167. The eighth line, "Default Pitch" shows the horizontal spacing of characters in a font in characters per inch. A 12 pitch font prints 12 characters per inch. Actually the default pitch figure defines character spacing only for fixed spaced fonts. For proportionally spaced fonts the figure displayed is the reciprocal of the width of space character. For example a default pitch of 27.27, as in the DEMO.SF2 file, means that 27.27 spaces will fit in one horizontal inch. The width of the individual characters of a proportional font is shown on the lower part of the screen under CHARACTER DATA. The ninth and tenth lines show the dimensions of the font's cell, in HP dots. Since HP uses 300 dots per inch in their font specifica- tions, dividing the displayed cell dimensions by 300 will provide you the physical dimensions of the cell. For example, if the cell width is 41 dots, it is 41/300 = 0.137 inches wide. These dimensions are used to draw the cell on the graphics portion of the screen. The eleventh line, "BaseLine dst" shows the distance from the top of the cell to the baseline, in dots. This value is used to position the baseline in the FONTVIEW graphics window. The twelfth line, "x" height displays the distance, in dots, from the baseline to the x-height line, as described earlier. Many shareware fonts leave this field blank; and, if this has been done, no x-height line will appear in the FONTVIEW graphics window. The final, thirteenth line of the font data area shows the dot magnification used by FONTVIEW to display the font characters. As discussed earlier, an X-magnification of 9 means that 9 dots are displayed horizontally, for each single horizontal dot printed by your laserjet printer. The true physical magnification, naturally depends on the size of your screen. For my NEC Multisynch monitor, with a horizontal image of about 10 inches and vertical image of about 8 inches, the overall image magnification is about 4.7 times the X-magnification shown. Thus, for a horizontal dot magnification of 9, the actual physical magnification is 4.7 * 9 or about 42:1. Similarly, the vertical magnification is about 6.9 times the displayed amount, or 41:1 for a Y-magnification of 6. If the ratio of X- magnification to Y-magnification is maintained at 3:2, the screen image aspect ratio (vertical to horizontal proportions) matches the printer aspect ratio within about 3%. FONTVIEW automatically maintains this 3:2 ratio unless the font is so large (more than 30 points) that the image cannot fit on the screen. If this occurs, the program will shift to a one dot:one dot magnification which will allow fonts of over 60 points to be displayed, although fonts will appear tall and skinny on the screen due to the distortion in aspect ratio. Also, at 1:1 magnification, all characters are displayed as solids since each "display dot" cannot be further reduced in size to produce the grid-like dot display appearance. CHARACTER DATA Below the font data area of the text window is the Character data. This data changes for each character displayed and is updated immediately before each character is displayed in the graphics window. The first line shows the ASCII number of the character. To the right of this, in parenthesis, is the EGA text-mode representation of the character. Above ASCII 126 this may not match the actual character shown in the graphics area, because EGA text mode displays the equivalent of HP's PC-8 symbol set. If your font contains one of the more than 30 other symbol sets, the characters will not be the same, particularly above ASCII 127. Nonetheless, the more commonly- used characters below ASCII 128 should match. If your font contains characters below ASCII 32, the EGA text mode character may not be shown in parenthesis since many of these characters are control characters which would scroll or otherwise distort the screen if displayed. The second and third lines show the dot width and height of the character. The HP LaserJet II technical reference manual indicates that a character height or width larger than the corresponding dimension of the cell specified in the font descriptor will invalidate the character download, although my experience suggests the rule is somewhat more complex than it appears: for fixed pitch fonts, if the left offset (see below) plus the character width does not exceed the cell width, the character is OK; for proportional fonts, if the "delta X" (discussed below) does not exceed the cell width, it's OK. It is possible, therefore, for a valid LaserJet character to extend beyond the right boundary of the graphics cell, although in practice this is rare. FONTVIEW will beep when it reads a character whose height or width violates the LaserJet cell rules, but will attempt to display the character. If FONTVIEW terminates abruptly, immediately following a beep, it is likely that the character was larger than the cell and would not fit on the screen at the dot magnification being used. The fourth line displays the left offset, in dots. This is the number of dots that the LaserJet printer moves to the right before printing the character displayed on the screen, and thus is how character spacing is performed in the printer. Note that this value is negative for characters which are moved to the left before printing. FONTVIEW uses the left offset value to position characters within the graphics screen cell, except that negative values are ignored for display purposes. The fifth line shows the top offset, in dots. This is the number of dots above the baseline at which the top of a character begins. For example the portrait-orientation "A" in DEMO.SF2 has a character height of 29 dots and a top offset of 28 dots. This means that the top of the character begins 28 dots above the baseline. Since the character is 29 dots high, this results in the bottom of the character coinciding with the baseline. The sixth and last line shows the Delta X value in dots. This is the number of dots the printer moves from where it left off at the end of the previous character to where it moves after printing the character being displayed. This Delta X defines the width of a character on the printer; this is the value which many word processors include in Width Tables so that they can properly space text which will use a downloaded font. TROUBLESHOOTING If FONTVIEW abruptly terminates before displaying any characters, it may be that extraneous bytes are contained in the file. Run FNTCLEAN to clean up the file and then run FONTVIEW on the new file created. If FONTVIEW terminates before displaying any characters, and you are attempting to view a file already processed by FNTCLEAN, recheck the path and filename you typed in on the command line. Particularly check that the path exists since I have bombed FONTVIEW many times by mistyping the path name. If FONTVIEW terminates in the middle of a file, it may be that the manual magnification is set too high, or because some character dot data overflows the "cell" boundary defined in the font header and cannot fit on the screen. Try running FONTVIEW at reduced magnification. For example, if the original magnification was 9 by 6 (x-mag, y-mag), try using /M6,4 on the command line. This is the next lower magnification which preserves the 3:2 x- to y- magnification ratio which results in correct vertical and horizontal proportions on the screen. REGISTRATION You will soon notice that many shareware and even commercial fonts don't sit on the baseline. For some unknown reason, many fonts sit one dot above the baseline, although I've never observed this in a HP-designed font. This offset does not impair the font's performance in your Laserjet printer since if all characters are situated one dot (1/300 inch) too high, it is not noticeable, however it is annoying when you view the font using FONTVIEW. Also, if the character sits one dot too high, it is likely the x-height line will appear one dot too high as well. Furthermore, many font makers do not bother to set the x-height since it does not affect the font's performance in a printer. Again, though, it is annoying since the x-height line is helpful when viewing any lower-case letter in FONTVIEW. Finally, sometimes a font will contain characters which violate the LaserJet cell boundary rules or contain dots so far outside the cell that FONTVIEW bombs. If you register FONTVIEW and FNTCLEAN, you will receive the latest versions of the two programs on a diskette, PLUS, you will receive a copy of the programs FONTFIX and LJROTATE. FONTFIX, which works on portrait soft fonts, is a very hard- working program. It has all of the features of FNTCLEAN, plus: 1. Displays the hexadecimal values and interpretation of all 64 bytes of the LaserJet II font header. 2. Displays the HP LaserJet escape sequence which completely identifies the font and can be used by your word processor or spreadsheet to designate the font for use, once it has been downloaded. 3. Sorts its output file by ascending ASCII numbers. Amazing- ly, I have viewed many font files which do not have their character data sorted in ASCII order. 4. Has a Command line option to move the Baseline for all characters Up or Down by a user-selected number of dots. 5. Has a Command line option to set the font's "x-height" either manually (in dots), or have the program set the font x-height using data from the lower-case "x" character (ASCII 120) if it is included in the font file. 6. Goes through each character in a font on a bit (pixel) level, along the top, bottom, left and right edges, eliminating superfluous rows of dots which are all "off"; then adjusts left offsets, top offsets, character widths and heights appropriately, and reconstitutes the character. It then returns to the FONT header, and sets the cell width, cell height, and baseline distance such that these values are correct. This results in a font which uses the minimum number of bytes to fully describe each character, thus minimizing download time, LaserJet memory requirements, and disk storage requirements. Several shareware fonts do not make effective use of top offsets or left offsets. If you display a font which uses the same height and width for each character, it is likely that the size of the file can be reduced. For example, the shareware font LARGEHLW.SFP was 34,773 bytes long originally, but only 16,992 bytes long after processing by FONTFIX. Naturally, the modified font performed identically on my LaserJet printer. LJROTATE creates a LANDSCAPE font from your PORTRAIT font input or a PORTRAIT font from your LANDSCAPE font. It processes characters in a manner similar to FONTFIX to set correct cell dimensions, sort output characters into ascending ASCII order, and minimize the number of bytes to define each character, then rotates the character. Since many fonts are available in only one orientation (portrait or landscape), LJROTATE can be very useful. I now don't bother to download both orientations of the same font. Instead, I download the portrait font, set the baseline and x-height with FONTFIX, and then run LJROTATE to create a landscape font with the correct baseline distance and x-height. You may register both FONTVIEW and FNTCLEAN, and receive FONTFIX and LJROTATE by forwarding $17.00 (California residents add $1.11 sales tax) to: S.H. Moody & Associates, Inc. 1810 Fair Oaks Ave. South Pasadena, CA 91030 Please note that you are registering for FONTVIEW so I can distinguish your order from orders for other products.