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BASWIND.MRG POP-UP WINDOWS FOR COMPILED BASIC PROGRAMS by Dave Evers 2500 Larch Rd. #58 Quincy, IL 62301 using CALLS to ADBVAS.LIB by Thomas Hanlin III BASWIND.MRG is a general purpose BASIC subroutine which can be incorporated into Compiled BASIC programs to allow for simple windowing capability with a minimum of programming effort. By "simple" I really do mean simple: about the only thing this sub- routine does is put the window on the screen. What you do with the window, what you put in it, and what you do with it once you're done is all up to you. However, it does give you the ability to make your compiled programs look "high-tech"; even if your programming isn't. I wish I could take full credit for all of the capabilities of BASWIND.MRG. The truth is, however, that very little of the "meat" of this program is my doing. BASWIND.MRG relies heavily on the routines in the excellent assembly language library of advanced BASIC functions contained in ADVBAS.LIB. Perhaps the most important of these features is the XQPRINT command, which writes data to the screen extremely quickly. It is this command which makes the BASWIND subroutine useful because entire sec- tions of the screen can rapidly be "painted" into a colored, framed "window" in a fraction of a second. True windowing, of course, involves much more than just making a box appear quickly on the screen. Programs such as TopView, Microsoft Windows, Desq, and others allow such features as treating the windows as virtual screens with relative cursor positioning and independent scrolling; multiple layers of overlapping panels that can be added and removed from a screen while leaving the underlying data undisturbed, and delegating the screen output from multiple programs to their assigned windows. BASWIND.MRG is not likely to put these companies out of business. (For that matter, it's not likely going to put me in business, either). However, other features of the ADVBAS library can be combined with the BASWIND.MRG subroutine to allow at least a small percentage of these features to be incorporated into your programs. Commands are included in ADVBAS.LIB to save and restore the screen to an array; scroll a rectangular section of the screen up or down or clear it; print to the screen rapid- ly, and many other useful functions. Virtually any program that is compiled can benefit in some way from ADVBAS.LIB; and hope- fully, from BASWIND.MRG as well. ADVBAS.LIB was written by Thomas Hanlin III, and I and the rest of the PC users community owe a debt of gratitude to this talen- ted and generous man for his contribution to the free distribu- tion of knowledge. Mr. Hanlin, our hats are off to you! INSTALLING BASWIND.MRG Before you can take advantage of the capabilities of this sub- routine, of course, you must MERGE it into your BASIC program. BASWIND is distributed as a .MRG file in ASCII format to allow it to be easily added to any program. Just load your program into memory, and then type: LIST 55000-55590 at the command level. This will tell you if your program uses line numbers that BASWIND might conflict with. BASWIND uses line numbers beginning at 55000 and ending at 55590; so obviously if your program already uses these line numbers you should renumber the .MRG file to another area not used in your program before MERGEing it. Once you have done this, or if the response to the above query indicates your program will have no problems, simply type: MERGE BASWIND.MRG After a few seconds, the BASIC ready prompt will return and BASWIND will be integrated into your program. Before you do any- thing else, SAVE your program so that your working copy will have BASWIND installed. Then you're ready to start taking advantage of the advanced and awesome (ahem!) capabilities of the subroutine. USING BASWIND BASWIND is invoked, like any other BASIC subroutine, by the GOSUB command. If you MERGEd BASWIND as distributed, you would use GOSUB 55000. If you had to renumber the subroutine, of course, you would use the new beginning line number in your GOSUB statement. However, in order to get anything useful out of the module (and probably in order to keep your program from locking up), you first have to set up some parameters that the subroutine will use. This is done by making assignments to the following variables prior to the GOSUB statement: ULR - (Upper Left-hand Row) - the screen row of the Upper Left-hand corner of your desired window. Value should be between 2 and 23 (for reasons explained below). WARNING - the subroutine does not check for proper values. You must check these yourself or ac- cept the consequences. ULC - (Upper Left-hand Column) - the screen column of the Upper Left-hand corner. Value should be between 2 and 79. LRR - (Lower Right-hand Row) - the screen row of the Low- er Right-hand corner of your window. Value should be greater than ULR but less than 23. LRC - (Lower Right-hand Column) - The screen column loc- ation of the Lower Right-hand corner. Value should be greater than ULC but less than 79. FRAME - A number between 1 and 4 indicating the type of frame to be drawn around your window. Valid frame values are: 1 - Single Line Frame 2 - Double Line Frame 3 - Single Horizontal Line, Double Vertical Line Frame 4 - Single Vertical Line, Double Horizontal Line Frame NOTE: The frame is drawn * around * the window coordinates specified in ULR,ULC,LRR, and LRC. Thus, the dimensions of your window will actually be two columns greater in width (one on each side) and two rows greater in length (top and bottom). This is why you should make allowances in the value of the window corners. Allowing the frame to fall outside proper values will cause unpredictable results. FORE - The color of the frame in the window. Standard color attributes are used (Black=0, Blue=1, etc.) and valid values are 0 to 15. BACK - The actual color of the window panel. The area de- fined by the corners of the window will be cleared to spaces in the background color specified. Val- ues considered valid are 0 through 7. GROW - A "switch" used to indicate to the subroutine if the window should "grow" from a small box at the midpoints of the coordinates to full size. A value of 1 indicates the window should grow. A value of 0 indicates it should not. The "growing" illusion is most effective for windows of medium size; and is better suited to "wide" windows rather than "tall" ones. SHADOW - Another "switch" to indicate if the window should have a black "shadow" under it offset down and to the left. This gives a three-dimensional effect that seems to "raise" the window away from the screen. A value of 1 indicates a shadow is desired while a value of 0 means no shadow. WARNING - Adding a shadow to the window increases the effective window size by 3 columns to the left of the window and 1 row below. These additions must be consid- ered when assigning the corner values since invalid values that fall off the screen will produce unpredictable results. NOTE: Windows that grow and windows with shadows are mutually exclusive. That is, a window that is desired to grow cannot have a shad- ow. The on-screen effect of such a combin- ation was determined to be undesireable. The "grow" switch takes precedence. If a window is created which calls for both a shadow and a growing attribute, the shadow will be cancelled and the window will grow. LABEL$ - A character string that will serve as a label for the window. The label will appear in the top line of the frame on the left-hand side, enclosed by square brackets ([ ]). If the length of the label is greater than the width of the window, the label will be omitted. The attributes for the label are the same as for the window frame. All of the above variables (with the exception of LABEL$) must either be declared globally as integers by means of a DEFINT statement early in the program; or must have the specific integer identifier (%) attached wherever they appear in the program. The BASIC compiler is picky about this; so be sure to verify that the type assignment is correct. EXAMPLE To produce a window with a blue background, a bright white single line frame, and a label of "Ye Olde Window"; between columns 20 and 60 and rows 4 to 20, the following statements would be required: 100 ULC=21:ULR=5:LRC=59:LRR=19:FORE=15:BACK=1:FRAME=1 110 SHADOW=0:GROW=0:LABEL$="Ye Olde Window" 120 GOSUB 55000 To generate a green window with a black single horizontal, double vertical line frame, with a shadow; the following statements would be needed: 200 ULC=13:ULR=3:LRC=45:LRR=15:FORE=0:BACK=2:FRAME=3 210 SHADOW=1:GROW=0:LABEL$="" 220 GOSUB 55000 To "grow" a cyan panel in the middle of the screen with a yellow double line frame, the program would make the following call: 300 ULC=10:ULR=5:LRC=70:LRR=19:FORE=14:BACK=3:FRAME=2 310 SHADOW=0:GROW=1:LABEL$="" 320 GOSUB 55000 Of course, once the window is placed on the screen, it is up to you to fill it with data by means of LOCATE, COLOR, and PRINT statements. The above window calls only give you the canvas on which to work. You, as the artist, produce the masterpiece on your own. ADVANCED WINDOWING FUNCTIONS The basic BASWIND subroutine calls give you a fair amount of flexibility in producing simple windows on the screen; but to really add some "pizzazz" to your programs, you need more capability than just these humble beginnings. This is where some of the additional features in the ADVBAS library come into play. By combining some of these functions with the easily-used BASWIND subroutine, some very powerful and exciting possibili- ties are generated. Actually, compiled BASIC becomes a very effective development medium with some impressive capabilities when all of these advanced tools are put to use. Making "Pop-ON/Pop-OFF Windows" Most programs which use windows make very effective use of the screen by allowing a window to "pop on" to the screen over the existing information, display some important data such as help or statistics, and then "pop off" on demand; leaving the screen data undisturbed. Obviously, the simple commands introduced earlier would not be of use by themselves because they destroy the information on the screen at the window coordinates. In order to allow "non-destructive" windows on the screen, the contents of the screen must be saved prior to adding the window, and then quickly restored when the window is removed. Fortunately, the ADVBAS library includes two special commands that make this work extremely easy. The SCRSAVE and SCRREST functions allow the virtually instantaneous transfer of screen data to and from a numeric array. Once the array has been dimensioned and the space reserved in memory, the entire screen can be saved in just a fraction of a second. The window can then be drawn anywhere on the screen without regard to the loss of screen data. The SCRREST command performs the dual function of erasing the window and restoring the screen's previous contents. And all of this magic can be accomplished with just a few lines of simple BASIC code. A typical use of the SCRSAVE and SCRREST commands would be as follows: 10 OPTION BASE 1:DIM SCR%(4000) . . . 100 WHER%=VARPTR(SCR(1)):CALL SCRSAVE(WHER%) 110 CURSX%=pos(0):CURSY%=CSRLIN . . . 150 REM Add window to screen . . . 200 WHER%=VARPTR(SCR(1)):CALL SCRREST(WHER%) 210 LOCATE CURSY%,CURSX% . . . While it is theoretically possible to maintain multiple arrays to allow for several levels of non-destructive windows, each array uses 8000 bytes and thus rapidly depletes free memory space. Most programs can do nicely with only one array and one level of windowing support. Scrolling and Clearing Data Inside a Window Another powerful feature made possible by the ADVBAS library is the ability to scroll and clear a selected area of the screen, independent of the rest of the data displayed. When combined with the effective display techniques described above, this impressive capability mimics that of expensive commercial prog- rams. And best of all, the function calls are as easy to use as the routines described above for BASWIND. The SCROLL and BKSCROLL commands take five parameters; four of which are already defined as ULC,ULR,LRC,LRR in the BASWIND window definition and display routine. Since the frame of the window is drawn around the area defined by these coordinates, the scrolling can take place within the confines of these windows without any further complications. The fifth parameter, the number of lines to scroll, is easily set. Most often, it will only be one line; so that another line can be PRINTed into its place either on the top or the bottom depending on whether the scroll is up or down. In the special case that the number of lines is zero, the entire area is cleared with spaces of the background attribute; so an easy way of clearing a window is available as well. As with the BASWIND parameters above, all of the SCROLL variables must be integers. Thus, either a DEFINT statement must be in place early in the program or the variables must carry the "%" type identifier throughout the program. The program statements required to scroll up the contents of a window defined and displayed by BASWIND would be as follows: 100 LINS=1 110 CALL SCROLL(ULC,ULR,LRC,LRR,LINS) To scroll the same window down instead, the following series of statements would be used: 100 LINS=1 110 CALL BKSCROLL(ULC,ULR,LRC,LRR,LINS) And to clear the window of any data: 100 LINS=0 110 CALL SCROLL(ULC,ULR,LRC,LRR,LINS) FURTHER ENHANCEMENTS The routines presented here allow a good start in providing advanced windowing features in almost any compiled BASIC program; but there is certainly room for improvements and enhancements to these basic ideas. A few of which that come to mind immediately are: - Being able to move the window on the screen in real time under the control of the cursor keys. Such a procedure would involve rapidly restoring the orig- inal screen and redrawing the window at the updated position; something that seems feasible with the ADVBAS features. - Adding clipping to the display of data in the window. For example, moving a window across a text file under cursor control. - "Collapsing" windows which are removed from the screen in the opposite manner to "growing". - A means of providing "point and select" functions with- in a window by moving a highlight bar up and down a list of options. I am sure that with a little experimentation with these routines, you will think of many more possibilities. Should you come up with a routine that you like, please upload it to your favorite bulletin board to help pass along this free exchange of information. Drop me a line also, as I would like to keep up with all of the developments these initial offerings inspire. COMPILING PROGRAMS As mentioned before, the routines in BASWIND and ADVBAS are available only in Compiled BASIC. DON'T TRY TO USE THESE PROGRAMS IN INTERPRETED BASIC!!!! At the very least, your computer will probably lockup requiring a re-boot. At worst, your system could go crazy, maybe even to the point of erasing data on disks in the drive. You are forewarned! BASWIND requires no special handling when it comes to compiling your program. Just make certain that all of your variables passing parameters to the BASWIND subroutine are identified as integers, and you will be able to proceed with the compile operation as with any other program. The actual compilation of your program should be straight- forward. However, once you get to the LINK operation, you MUST remember to list ADVBAS in response to the LINK program's request for library (LIB) files. Failure to do this will result in unresolved external reference errors. This is true even if you are using only BASWIND functions with no ADVBAS routines in your program, since BASWIND uses the XQPRINT function in ADVBAS as the heart of its operation. ACKNOWLEDGEMENTS As mentioned earlier, the ADVBAS.LIB library upon which all of the routines in BASWIND.MRG are based was developed by Thomas Hanlin III. For convenience sake, I have included this library along with the accompanying .DOC file as part of the BASWIND.ARC package. Tom has done an excellent job of providing many useful features in an economical and well documented package. In the .DOC file, Tom asks for a minimal contribution if you find these routines useful. I have sent him my check; and I strongly urge you to do so as well. To keep this spirit of information exchange alive, those people who make such a generous effort deserve to be rewarded. I am deeply indebted to Tom for his routines which are key to the operation of BASWIND. But as I look at my bank account, I find that I am deeply indebted, period. Thus, I humbly request that if you find BASWIND to be of some use to you that you acknowledge your appreciation in a similar contribution of $10. Unlike Tom, I don't guarantee you anything back for your money. I don't have any other programs to give you; and I've included all the source code in this package. But I do promise that I'll like you a lot if you do send me money. And just the fact that I haven't burdened down the code with a message that pops on the screen and begs for money until you "PRESS ANY KEY TO CONTINUE" ought to be worth something! Whether or not you feel BASWIND is worth anything, please feel free to use it to your hearts content; copy it shamelessly and give it to all your friends and enemies; use it in your commercial programs and sell them for hundreds of thousands of dollars. But whatever you do, keep contributing to the Public Domain and FreeWare/ShareWare community. The best people in the world live here! Dave Evers 2500 Larch Rd. #58 Quincy, IL 62301 DISCLAIMER OF LIABILITY I, David Evers, as author of the BASWIND.MRG subroutine contained in this package, hereby disclaim all responsibility for any consequence arising from the use, misuse, or non-use of any of the materials included herein. If this scares you and you feel that you can't in good conscience use this product without deposits and bonds and insurance policies for millions of dollars, THEN DON'T USE THIS SOFTWARE. If you are afraid that use of this product will damage your reputation, turn your green screen monitor amber, change your house AC voltage from 110 to 220, or make your hair fall out; THEN DON'T USE THIS SOFTWARE. And if by chance you DO use this software, and your spouse leaves you, your children sell the house, your health fails, and your hard disk crashes, THEN DON'T COME CRYING TO ME. With this software, "you don't pays your money, but you still takes your chances"! ME CRYING TO ME. With this software, "you don't pays your money, but you still takes your