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BOX A Program for Creating and Editing Screen Images version 1.3 (C) Copyright 1986,1987,1988 by Nescatunga Software All Rights Reserved ======================================================= BOX USER GUIDE PAGE 2 ======================================================= TABLE OF CONTENTS License and Registration Information..................3 Introduction..........................................4 Making Backup Copies..................................5 Running BOX on a Floppy-Based System..................5 Installing BOX on a Hard Disk.........................5 Running BOX on a Hard Disk System.....................6 The Main Menu.........................................6 Draw Menu...........................................7 Load from Disk......................................8 Save to Disk........................................8 ASCII File Format...................................9 Memory File Format..................................9 Packed File Format.................................10 Path/Directory.....................................11 Clear Screen.......................................11 Exit Program.......................................11 The Draw Menu Functions..............................12 Type Labels........................................12 Insert Mode (Ins)................................12 Delete Line (F9).................................13 Insert Line (F10)................................13 Draw Boxes.........................................13 Move...............................................14 Color Change.......................................14 Block Functions....................................15 Select Box Drawing Style...........................16 Repeat.............................................16 Paint Areas........................................17 Erase..............................................18 On the Fly Changes.................................19 ASCII Table.......................................19 Turbo Pascal Programming Considerations..............20 Displaying ASCII Format Screens....................20 Displaying Memory Format Screens...................20 Displaying Packed Format Screens...................21 Using BOX Screens for Context Sensitive Help.......21 Capturing screens from other programs with GRAB......23 ======================================================= BOX USER GUIDE PAGE 3 ======================================================= LICENSE AND REGISTRATION Box is not a public domain program. Rather it is being distributed under the User Supported Software concept. The program has been copyrighted by the author who reserves all rights. You are granted a limited license to use and copy the program according to the terms below. As an individual you may freely copy the BOX program and its associated files for your evaluation and the evaluation of others so long as no price or other consideration is charged. Shareware distribution organizations may copy the BOX diskette and share it with their members so long as no price is charged other than a reasonable distribution fee not to exceed the cost of a diskette and handling. The program, associated files and documentation must always be distributed together. You may not modify the program or the documentation. You may not reprint the program manual in any way. Schools are granted permission by the author to copy BOX as many times as needed so long as the registration fee has been paid for each building the program will be used in. REGISTRATION FEE If you find BOX useful we ask that you register as a BOX user by sending $20.00 to: Nescatunga Software Box 5942 Katy, TX 77450 Although BOX is relatively small and tightly focused in its purpose, it represents many, many hours of work. We can continue to enhance BOX and develop other shareware products ONLY if you support the product and the shareware concept. ======================================================= BOX USER GUIDE PAGE 4 ======================================================= INTRODUCTION Congratulations. You now have at your service the world's best screen designing tool. With BOX you can create in minutes the kind of flashy, professional- looking data entry screens and menus that would take hours with most editors. BOX is a screen editor. You start with a blank screen and, using special screen editing functions, type headings and text, paint, shade or erase in any color combination you desire. BOX has special functions such as REPEAT, PAINT and ASCII-Table-Selection which are tailored specifically to screen creation and far exceed what is available in other text editors. Drawing intricate intersecting boxes on the screen with the special box-drawing characters is literally child's play. After you have used BOX's screen editor to create a colorful, snazzy screen you then save the image using BOX's SAVE function. SAVE creates a disk file of your screen that you may load directly onto the screen from a Pascal or C program. Later if you have changes to make to the screen it is a snap to LOAD it back into BOX's editor and make the changes. Although BOX may sound like a graphics program, it is not. BOX uses regular ASCII characters so that any BOX-created screen may be displayed on any color or monochrome monitor. Applications for BOX include but are not limited to: Input screens for data base entry Menus Help Screens Program Logo screens Demonstration Screens Program Prototyping Computer "doodling" In addition to the BOX program the diskette contains sample routines you can incorporate in your Turbo Pascal programs. When you use these routines, the screens you create pop onto the monitor virtually instantaneously. These routines are not large or complicated and could easily be translated into other languages such as C. ======================================================= BOX USER GUIDE PAGE 5 ======================================================= BOX will run on any IBM PC under DOS. Although BOX does use color to advantage (CGA or EGA adapters) it will also run on monochrome systems as well. We have tested BOX on several IBM compatible PCs and have discovered no problems. Be aware however that BOX incorporates several low-level functions which may not work on some IBM near-compatibles. Please let us know the nature of any problems you discover on your system. MAKING BACKUP COPIES BOX is not copy protected so make as many back-up copies as you think you will need. To make back-up copies or distribution copies for other users first boot up your computer with DOS. Place the BOX diskette in the A drive and a blank, formatted diskette in the B drive. At the A prompt type the following command to copy all files from the A diskette to the B diskette: A> COPY A:*.* B: RUNNING BOX ON A FLOPPY-BASED SYSTEM To use BOX on a floppy disk system first boot up your computer with DOS. Put the BOX diskette in the A drive and type the following command at the A prompt: A> BOX The BOX program should start by displaying a logo with a large word BOX outlined on the screen. Remember that BOX looks for its logo file and its help files on the same drive where it is started. So starting the program from another drive, as shown in the example below is wrong. B> A:BOX (Wrong) After you have started BOX you may change the data drive and/or directory where BOX stores and retrieves its data files. INSTALLING BOX ON A HARD DISK To install BOX on a hard disk first make a directory to hold the BOX program and associated files. Then, with ======================================================= BOX USER GUIDE PAGE 6 ======================================================= the BOX diskette in the A drive, copy all BOX files to the directory: C> MD\BOXX C> CD\BOXX C> COPY A:*.* C: The three commands above will create a new directory named BOXX, change to that directory and copy all BOX files from the BOX diskette to the BOXX directory on the hard disk. If you would prefer to leave the BOX example programs on the disk then substitute the following COPY statements for the one above: C> COPY A:BOX.EXE C: C> COPY A:BOXHELP.* C: C> COPY A:BOXLOGO. C: RUNNING BOX ON A HARD DISK SYSTEM To start the BOX program, issue the following two commands to change to the BOXX directory and initiate the program: C> CD\BOXX C> BOX Remember that BOX must be started from the same directory and drive as its associated files. The drive and directory where screen-image files are stored and retrieved can be changed from BOX's Path/Directory command. THE MAIN MENU Even if you have limited experience with PC software you will find BOX a snap to use. BOX uses the following conventions which are standard with many popular software products: "Point and Shoot" Menus "Escape" for Menu "F1" for Help In fact, if you're in a hurry to try BOX, go ahead and fire it up. The program's user interface is intuitive ======================================================= BOX USER GUIDE PAGE 7 ======================================================= and you will likely be using all of BOX's features (except for BOX's "on the fly" drawing changes which are well hidden) without reading this manual. However to get the most from BOX it is a good idea to come back and read this manual later to see if you may have missed a trick or two. If you get stuck running BOX just hit F1 for help. When you use BOX's help screens it is interesting to note that they were created with BOX and are displayed by Pascal routines similar to the routines shown later in this guide. The Main Menu appears when you start BOX. You will return to it to SAVE and LOAD files, to change the data PATH, to CLEAR the screen and to EXIT. To select the desired menu item move the reverse-video cursor with the up and down arrow keys. When you have selected the action you want hit the enter key to activate it. As an alternative you may select an item from the menu by hitting the first letter of the description. For example just hit the letter S if you want to select SAVE FILE from the main menu. Hitting the letter S is equivalent to placing the bar cursor on SAVE FILE and hitting enter. After you become familiar with the commands you will find this approach more efficient because it requires fewer keystrokes. Please note that the Esc key has special meaning under BOX's menus. Hitting Esc is the same as placing the bar cursor on the last item and hitting enter. Usually this will cause an EXIT to a higher menu. On the main menu however, hitting the Esc key will Exit the BOX program (after a safety prompt). DRAW MENU If you select DRAW MENU from the main menu, another menu will appear with a list of selections for drawing and painting boxes on the screen. From the DRAW menu you may : Type labels and text on the screen Draw boxes like an etch-a-sketch Move around the screen without drawing ======================================================= BOX USER GUIDE PAGE 8 ======================================================= Change background and foreground colors Choose between four box drawing styles Repeat any character in any direction Paint the boxes any color (including blink) Erase lines drawn in error These seven functions make it easy, even fun, to create a screen image and draw and edit boxes and line shapes using the PC's special box drawing characters. I'll return to the DRAW menu later and cover each of the functions in detail. But first let's cover the other functions on the main menu. LOAD FROM DISK The Load function loads a screen image file you have saved previously with the SAVE TO DISK function described in the next section. To load a file first select the file format the original screen was saved under; either ASCII or Memory (see description under SAVE below). BOX will then display a directory of files on the current drive/path and prompt you for the file name. Type the file name you want to load and hit enter. If the file you want to load is not on the current drive/path you have two options. First you may hit escape to return to the main menu and there select PATH/DIRECTORY to change the drive/path then return to the LOAD screen to load the file. Or you may simply type the drive and directory prefix to the file name at the bottom of the LOAD screen. You may LOAD standard ASCII files created with other editors (including Turbo Pascal's) and word processors. But BOX will LOAD only the left most 80 characters of the first 25 lines. Take care not to LOAD a file longer than 25 lines then SAVE it with the same name. BOX will overwrite the original file but save only the first 25 lines. Any additional lines will be lost. SAVE TO DISK The save function writes a disk file containing the screen image you have created and edited with BOX's DRAW and TYPE functions. To use SAVE you must first select the file format and, when prompted, provide a ======================================================= BOX USER GUIDE PAGE 9 ======================================================= file name. Please note that BOX remembers the last file name you used so if you LOADED a file, BOX will SAVE the modified screen under that same file name unless you change it. ASCII FILE FORMAT With BOX you may store a screen image in one of three different formats; the ASCII format, the Memory format and the Packed format. The ASCII format is the simpler and more standard of the three because it saves the screen in a text format that most word processors and editors (including Turbo Pascal's editor) recognize. ASCII files may therefore be further edited and printed with many other editors and word processors or included directly in you program's source code. However saving a BOX screen image in the ASCII format has some disadvantages. First, ASCII files lose all of the color attributes you may have drawn or painted on the screen. In addition ASCII screen images must be displayed line-by-line with write statements resulting in a slower display. MEMORY FILE FORMAT Memory format files, because they are essentially a snapshot "dump" of the video memory buffer, retain all color attributes (including blink) and can be instantly flashed on the screen using the code examples later in this manual. But unlike ASCII format files, memory files will look like gibberish to most editors and word processors. Usually this will present no problem since you can always edit memory format files with BOX. Many of the commonly available screen-capture programs use the Memory format. GRAB.COM, a program contained on the BOX disk, is a TSR (memory resident) screen- capture program which you can use to capture screen from other programs. When activated with ALT-PrtSc, GRAB saves the current screen image to the current disk drive in a Memory format. There are more instructions for using GRAB later in this documentation. ======================================================= BOX USER GUIDE PAGE 10 ======================================================= PACKED FILE FORMAT Except for one difference, Packed format files are identical to Memory format files in that they retain all color attributes and can be popped on the display instantly. The difference is that Packed format files use a simple run-length-encoding algorithm to compress the size of the file when it is written to the disk. You can save considerable space by using Packed format files if your screens have several blank lines or bordered boxes. Memory format files always require 4000 bytes of storage. A typical Packed format file will require around 2000 bytes. You should be aware, however, that in extreme cases (where every other character is different for example) a Packed format file can actually be larger than 4000 characters. If you are not sure which format to use, save your screen under both formats with a different name then examine the size of the files with a Directory command. Another consideration of using Packed format files is that the Pascal screen loading procedure you must include in your program, because it must decode and expand the packed file, is more complicated than the simple procedure for a loading Memory format file. It takes just a trifle more time to load a Packed file, but not so much time as to make this a major consideration. You must decide which of the three formats gives the greatest advantage to your requirements. In saving BOX files you may use any file names you wish. Please note, however, that if you do not add file extensions (a period followed by three characters at the end of your file name) BOX will add them for you using the following conventions: ASCII files xxxxxxxx.ASC Memory files xxxxxxxx.MEM Packed files xxxxxxxx.PAK If you choose to use the conventions above for your file names, BOX will highlight any file names that match the format you are using when it displays the directory of files during LOADing. ======================================================= BOX USER GUIDE PAGE 11 ======================================================= PATH/DIRECTORY With the PATH/DIRECTORY facility, which is available from the Main menu, you can see the current path and change the drive/path where BOX will store or retrieve screen-image files. BOX will display a directory of files on the selected drive/path when you enter the new drive/path. After you have typed in the drive/path where you want BOX files to be stored hit escape to set that path and return to the main menu. CLEAR SCREEN The CLEAR SCREEN choice on the main menu brings up a menu of CLEAR functions. CLEAR The CLEAR function erases all characters on the screen and sets the colors to those chosen. Use it when you have just saved a screen image and want to start with a fresh screen on another image or when you want to change the background from the default blue. COLOR CHANGE This choice on the CLEAR menu brings up a color smorgasbord for selecting the colors you wish to have on the cleared screen. FILL Select FILL to fill the entire screen with a character. An ASCII character selector box will pop up to allow you to select any of the 255 ASCII characters. With these characters you can create many interesting patterns. PAINT SCREEN PAINT changes the background and foreground colors on the screen but does not erase the characters. X EXIT Select EXIT on the main menu to leave the BOX program. If your last step was to SAVE a file, BOX will return ======================================================= BOX USER GUIDE PAGE 12 ======================================================= control to DOS immediately. However if your last operation was not a SAVE, BOX will ask you if you really want to EXIT. THE DRAW MENU FUNCTIONS Now let's return to the DRAW MENU and examine each of its functions in more detail. When you select DRAW from the main menu, BOX will display a list of selections for drawing and painting boxes on the screen including: Type labels and text on the screen Draw boxes like an etch-a-sketch Move the cursor around the screen without drawing Change background and foreground colors Move or paint blocks on the screen Select from among four box drawing styles Repeat any character in any direction Paint the boxes any color (including blink) Erase lines drawn in error Let's cover each of these functions in order: TYPE LABELS TYPE, which is the first function on the DRAW Menu, is a simple, full-screen text editor you can use to type text on a screen image. After you have selected TYPE simply locate the cursor where you want it on the screen and type whatever text you need. Since BOX works with only one screen at a time the limits of the typing area is 80 characters wide by 25 lines long -- a full screen in 80 character text mode. INSERT MODE In the TYPE function you may toggle the insert mode on and off by hitting the Ins. key. A large block cursor indicates that Insert is on, a small line cursor indicates that Insert is off. If Insert is on, all characters to the right of the cursor will be pushed to the right when you type. BOX does not word wrap nor does it save the characters that you push off the screen. Please remember that if you have the insert mode on and you hit the enter key you will break the ======================================================= BOX USER GUIDE PAGE 13 ======================================================= line at the cursor location and carry the tail of the line to a new line below. If insert mode is off the cursor will jump to the next line but it will not carry the tail of the line. DELETE LINE => F9 To delete a line, place the cursor on the line you wish to delete and hit F9. All lines below the deleted line are brought up one line and a blank line will be inserted at the bottom of the screen. The blank line will be in the current color scheme. INSERT LINE => F10 To insert a blank line, place the cursor just below the location you want the line inserted and hit F10. All lines below the inserted line will be pushed down one and the last line of the screen will be lost. DRAW BOXES Select DRAW BOXES from the DRAW MENU to draw lines and boxes using the arrow keys on the cursor control pad. Boxes will be drawn with the box drawing characters which are part of the extended ASCII character set which have codes between 179 and 218. There are 40 different characters with which you can draw single and double-line boxes. If you have ever designed a screen by entering the characters one at a time you know how tedious and time consuming it is. BOX allows you to throw away the list of ASCII codes and draw precise, colorful boxes with one finger. Think of DRAW as lowering a drawing pen onto the drawing pad (the screen). Lines will follow wherever you direct the cursor--up, down, left or right. DRAW will use whatever colors and box style you have previously selected. So you may wish to select COLOR CHANGE and BOX CHANGE from the DRAW MENU before you select DRAW. The entire screen of 80 characters wide by 25 lines high is available to you. One of the most interesting routines in the BOX program examines the screen around the line you are drawing to determine if a special intersection character is needed ======================================================= BOX USER GUIDE PAGE 14 ======================================================= to patch the box you are currently drawing with other boxes you may have previously drawn. There are 40 box drawing characters to cover nearly every conceivable intersection combination. However you should be advised that there are some intersections you can create for which there is no available ASCII character. We have tested BOX thoroughly and believe that BOX will find the proper intersection character if one exists. MOVE MOVE is the opposite of DRAW. MOVE lifts the box- drawing pen so that you may move the cursor with the arrow keys to a new location without trailing a line behind you. When you have moved the cursor to the new location, select DRAW to start drawing again. You may also move the cursor without drawing if you select the TYPE function from the menu. COLOR CHANGE When you select COLOR CHANGE from the DRAW MENU a color selection smorgasbord will appear on the screen. To select the colors you want simply use the up and down arrow keys to select Foreground or Background and the left and right arrow keys to select the color. A small arrow will move over the chart showing you which color you have picked and a sample of the colors will appear to the right of the display. Note that you may select from sixteen foreground and sixteen background colors. The second eight background colors are not really colors but cause the foreground characters to blink by turning on the blink bit in the color attribute byte. A little bit of blink, like hot pepper sauce, goes a long way. The color combination you select will stay in effect for the rest of the BOX session or until you change it regardless of whether you are typing text, drawing boxes or painting. If you want the background of the screen a different color than it is you may return to the main menu and select CLEAR or you may use the PAINT function from the DRAW menu. Be sure you don't select the same background and foreground colors. If you do everything you draw or ======================================================= BOX USER GUIDE PAGE 15 ======================================================= type will be invisible. If this happens hit Esc. to start again. BLOCK FUNCTIONS When you select BLOCK from the Draw menu, your first step is to identify the portion of the screen, or the block, you want to work with. Do this by moving the cursor to one corner of the block and hitting enter, then moving the cursor to the opposite corner of the block and hitting enter again. After you anchor the cursor on the first corner the program will highlight the block area by displaying it in reverse video. After you have identified the block size, the program will display a submenu of functions. MOVE BLOCK If you select MOVE BLOCK from the BLOCK menu simply use the cursor keys to move the identified block around the screen until you have placed it where you want it. Hit enter to position the block. The area where the original block was located is blanked out. CLONE BLOCK CLONE BLOCK is the same as MOVE BLOCK except that the original block is not blanked out but is left intact. So if you have created a fancy small pattern in one area of the screen that you want to repeat at other locations, use CLONE to move it. PAINT BLOCK PAINT allows you to change the background and foreground colors of the selected block area of the screen. Other PAINT functions are semi-automatic and operate on the interior of box lines, for example. But BLOCK PAINT allows great control over the PAINTing process. BLANK BLOCK This function blanks the selected area of the screen. DEFINE NEXT BLOCK ======================================================= BOX USER GUIDE PAGE 16 ======================================================= Use DEFINE to select another area of the screen for block operations. SELECT BOX-DRAWING STYLE Returning now to functions available from the main DRAW menu, the SELECT BOX TYPE facility allows you to select from among double line, single line or combination single/double line boxes. Simply pick the one you like. The box type you select will stay in effect until you change it even if you are not drawing. One small quirk in using the SELECT menu is that if you hit Esc while in the menu, you will have selected box type 4, the last on the list. So use the numbers to select the type you want or put the cursor on the box type and hit enter. REPEAT The REPEAT function has two parts. First REPEAT will allow you to enter the character you want to repeat. Then REPEAT will pause while you position the cursor anywhere on the screen. When you have positioned the cursor where you want it, hit enter to trigger the REPEAT function. You may now "draw" the repeat character any direction using the arrow keys. REPEAT works just like DRAW except you get to select any of the PC's 255 characters to draw with. You have the option of entering the repeat character from the keyboard or selecting the character from an ASCII Table. If the character you want to repeat is on the keyboard it is more efficient to enter it from there. But if the character you want is not on the keyboard you may select the character from the ASCII Table. When you select the ASCII Table option a window will pop up on the right side of the screen which contains 64 of the PC's 255 characters. A small box will surround the currently selected character. Move the small box with the arrow keys to select the character you want to repeat. Use the Up and Down arrow keys and PageDown and PageUp keys to scroll the ASCII table. Hit enter to select a character or escape to abort the REPEAT function. ======================================================= BOX USER GUIDE PAGE 17 ======================================================= Note that the character you have selected from the ASCII Table stays at-the-ready for later Repeat-Drawing if you need it. Just hit ALT-R to invoke the on-the- fly repeat function and you can "draw" the last- selected ASCII character in any direction. The ASCII Table can also be brought up On-the-fly by hitting ALT- A. PAINT AREAS The PAINT function contains several choices for painting parts or all of the screen different colors. COLOR Before selecting any of the paint functions it is necessary to choose the background and foreground colors you want the painted area to be. The COLOR smorgasbord allows the color selection. INTERIOR PAINT This function paints the interior of boxes the selected color but stops painting on the box boundary. To use the function move the cursor inside the box to be painted and hit enter. PAINT will start from the cursor position painting in every direction until it hits the box lines. Make sure there are no gaps in the box because PAINT will leak through the gap and paint the entire screen. LINE PAINT This function will follow any boxes or lines you have drawn and paint them the color you have selected. Put the cursor on the line you want to paint and hit enter. SCREEN PAINT Choose this function to change the colors of the entire screen. FILL The FILL function fills the area selected with a character of your choice. When you select the ======================================================= BOX USER GUIDE PAGE 18 ======================================================= function an ASCII selector table will pop up for character selection and you will be prompted to move the cursor inside the area to be filled. FILL will not leak into or out of boxes. The function is often used to create attractive background patterns around windows on the screen. These PAINT functions sounds complicated but play with them a while and you will get the hang of them right away. Just remember that if you select the same background color that you have in the box to start with, PAINT will appear as if it is not working if there are no typed labels in the box. With the exception of the FILL function, the PAINT functions do not destroy characters you have typed on the screen. They simply change the color attributes. This fact can be used to advantage if you want to leave the background color the same but change the foreground. For example if you have white characters on a blue background and you wish to have yellow characters on the same blue background then simply select yellow on blue and paint the area you want to change. The PAINT functions test to see if they have completed their tasks by looking at the colors all around where they starts. If the colors there are the desired PAINT colors the function thinks it is done and does no further processing. So be sure to move the cursor into an area that is not the paint color to start. If you have several areas to paint the same color move the cursor into the next area and hit ALT-P to invoke the on-the-fly PAINT function. ERASE While you are drawing, sooner or later you will turn a corner too soon or make some other mistake. To correct these mistakes, select ERASE. In essence, ERASE writes a blank character wherever the cursor is directed. ERASE does not restore the background color to what it was before. To accomplish this you must make a color change before you start ERASING. ======================================================= BOX USER GUIDE PAGE 19 ======================================================= ON THE FLY CHANGES After you become familiar with the DRAW MENU functions and memorize the initials -- D for DRAW, M for MOVE and so on -- you will want to take advantage of the ON THE FLY CHANGES. This facility allows you to change drawing functions on-the-fly while you are drawing simply by pressing a key. When you use this feature there is no need to return to the menu and select another function. For example while you are drawing a box you can hit ALT-M and BOX immediately switches you into the MOVE function. You may then move the cursor a few spaces, hit ALT-D and you're drawing a new box. ON-THE-FLY functions are quick and powerful but they happen without fanfare so you will have to remember what you are doing. ON THE FLY functions duplicate those available from the menu except for PAINT and REPEAT which work slightly differently. In their ON-THE-FLY forms PAINT and REPEAT are toggle functions you may turn on and off. For example if you are DRAWING you could hit ALT-M for MOVE, move the cursor inside a box and then hit ALT-P to toggle PAINT on and PAINT the box. This procedure varies from the three-part PAINT and REPEAT sequence the program steps you through when these functions are selected from the menu. ON-THE-FLY FUNCTIONS AVAILABLE ALT-T = TYPE LABELS ALT-D = DRAW BOXES ALT-M = MOVE ALT-C = COLOR CHANGE ALT-B = BLOCK FUNCTIONS ALT-S = SELECT BOX TYPE ALT-E = ERASE ALT-A = ASCII TABLE ALT-R = REPEAT (TOGGLE ONLY) ALT-P = PAINT (TOGGLE ONLY) ASCII TABLE (ALT-A) One unique on-the-fly function that is not directly available from the menu (it is available indirectly ======================================================= BOX USER GUIDE PAGE 20 ======================================================= from the REPEAT function) is the ASCII Table. If you want to use one of the upper or lower ASCII characters which cannot be entered from the keyboard on the screen, simply hit ALT-A. An ASCII Table will pop up on the right side of the screen with a selector box that you move with the arrow keys. Move the selector box over the character you want, scrolling with the arrow keys or PageDown or PageUp if necessary, then hit enter to select. The ASCII table will disappear and the character you selected will be printed on the screen at the last cursor position. The ASCII character you last selected from the ASCII table will stay at-the-ready to be used in the REPEAT function. To select the on-the-fly REPEAT function hit ALT-R. This combination of ASCII Table selection and REPEAT is a very powerful facility to create interesting and unusual effects with some of the "strange" ASCII characters. Some amazing displays can be created using the block and shading characters in unusual color combinations. The possibilities for attention-getting program logo screens are endless. TURBO PASCAL PROGRAMMING CONSIDERATIONS Creating screen images with BOX is easy and fun. But the real payoff comes when you incorporate your masterpieces in a program. Displaying and using BOX- created screens in your Turbo Pascal programs is easy with the example routines contained in file EXAMPLE1.PAS on your disk and described below. Please note that all example programs have been converted to Turbo Pascal 4.0 but, since only a few changes were required, may be converted back to 3.0 easily. DISPLAYING ASCII FORMAT SCREENS To display ASCII format screens created with the BOX editor, add a procedure to your program which reads the file produced by BOX and displays it line by line. The example routine LOAD_ASCII contained on your BOX diskette in file FILES.PAS will give you the idea. Copy and use the procedure in your own programs. DISPLAYING MEMORY FORMAT SCREENS To display a screen you have saved under the memory format you must read in the BOX-created file and move ======================================================= BOX USER GUIDE PAGE 21 ======================================================= the contents of the file directly into the Video display memory buffer. This buffer is located at memory address B800 (hex) for the color (CGA or EGA) adapters and at memory address B000 (hex) for the monochrome adapter. If you're not particularly interested in the technicalities of the video display, don't worry. Just incorporate the procedures CHECKCOLOR and LOAD_MEM from the file EXAMPLE1.PAS in your programs to read in a memory format file and display it on the screen. The screen should look just as you created it with BOX -- boxes, colors, blink and all. After you have displayed the screen you are free to write on it with normal Pascal Write statements. DISPLAYING PACKED FORMAT SCREENS Displaying a Packed format screen is similar to displaying a Memory format screen except the packed screen file must be unpacked before it can be displayed. A Packed format file uses a simple run length encoding structure. The idea is that if there are 20 blanks in a row on the screen, the Packed format just saves the blank character once along with the run length of 20. After the Packed format file has been unpacked it looks just like a Memory format file and may then be moved directly into the video memory buffer as described above. The example procedure LOAD_PAK contained on your disk in file EXAMPLE1.PAS will show you how. As with LOAD_MEM above you will need to check which video adapter is present with CHECKCOLOR to load the unpacked screen into either the color video buffer location or the monochrome video buffer location. USING BOX SCREENS FOR CONTEXT SENSITIVE HELP It is easy to create a context-sensitive help facility in your Turbo Pascal program with the BOX screen editor and a few simple routines such as those contained on the BOX diskette in file EXAMPLE2.PAS. The first step is to decide how many help screens you need and during what processing steps you want the help screens to display. There is no need to be skimpy on the number of help screens because you need not store ======================================================= BOX USER GUIDE PAGE 22 ======================================================= them in your program but rather you may store them on disk and called them in as needed. First, use the BOX editor to create each of the help screens. You may enter text, draw lines, use different colors and get as fancy as you wish. After you have completed each help screen save it using a memory or packed format. Now turn to your Turbo Pascal program. You will need to make several minor additions and modifications to tailor the help facility. First, from file EXAMPLE2.PAS, copy PROCEDURE HELPMSG (along with any other procedures and functions you decide to use) into your program. In PROCEDURE HELPMSG delete the help screen file names referenced there and add your own. You may have to extend the case statement to cover more than four help screens. Next, assign values to the variable HELPCONTEXT at various locations in your program corresponding to the help screen you want to display. For example if the help screen for your EDIT function is EDITHELP.MEM and you have assigned it position No. 2 in the HELPMSG case statement then be sure to set HELPCONTEXT := 2; in the first few statements of your EDIT Procedure. Now all that's left is to intercept each keystroke as it is entered and check it to see if the user has pressed F1 (or whatever you wish the help key to be). If the user has pressed the help key then your program should call HELPMSG to display the appropriate help screen. This feat is relatively easy if you are reading in one keystroke at a time. The function NEXTKEY in EXAMPLE2.PAS shows you how. But it is a bit more difficult to trap the help keystroke if you're using Turbo's read statement to read in an entire field at one time. If you really want slick context- sensitive help you must write your own IO routines examining each character as it comes in. This is not as tough as it sounds. That's all there is to it. If the user hits F1 any time during the execution of the program, HELPMSG and the other routines will do all the work. The right help screen will flash on the monitor and, when the user hits a key, will disappear leaving him at the exact spot he was when he asked for help. ======================================================= BOX USER GUIDE PAGE 23 ======================================================= CAPTURING SCREENS FROM OTHER PROGRAMS WITH GRAB On the BOX disk you will find the program GRAB.COM, a memory-resident screen capturing program. GRAB is a program that, when activated by pressing the ALT key and the PrtSc key simultaneously, saves the current screen image to disk under BOX's Memory format. You can use GRAB to capture screens from other programs and later modify those screens using the BOX editor and incorporate the screens into your own programs. To use GRAB first run the program by typing GRAB at the DOS prompt. GRAB will print a short message confirming that it has been loaded. You may now proceed to run any other program you wish. Whenever you want to save the screen image hit the ALT-PrtSc keys and GRAB will create a Memory format file containing the screen image on the current disk drive. If the drive or directory has been changed by the program or the batch file, GRAB will write to the new drive and directory. Later you can copy the files to whatever directory you wish. It is a good idea to wait until the program you are running is stable (i.e. waiting for a keystroke) before trying to capture the screen. When GRAB saves the screen it assigns a file name using the convention BOXnnn.MEM. The nnn portion of the file name starts with 000 and is incremented by one for each file saved. So the first file will be named BOX000.MEM, the second BOX001.MEM and so on. GRAB saves files only in the Memory format but it is easy to covert the file format later with BOX. Simply LOAD the file using a Memory format and SAVE the file using an ASCII or Packed format.