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Release Notes Fastgraph (tm) V3.0 Ted Gruber Software PO Box 13408 Las Vegas, NV 89112 (702) 735-1980 voice (702) 735-4603 FAX (702) 796-7134 BBS 72000,1642 CIS Copyright (c) 1991-1993 Ted Gruber Software. All Rights Reserved. ------------------------------------------------------------------------------ Introduction ------------------------------------------------------------------------------ The Fastgraph 3.0 release notes describe the new features added in Fastgraph 3.00 through 3.03 (hereafter collectively referred to as Fastgraph 3.0). The release notes will be of interest to customers who are already familiar with Fastgraph so they can get an overview of the new version. Among the many new features in Fastgraph 3.0 are: * SVGA support for 19 chipsets plus VESA in resolutions of 640x400x256, 640x480x256, 800x600x256, 1024x768x256, 800x600x16, and 1024x768x16. * Routines for displaying and creating GIF files (not in Fastgraph/Light). * Routines for FAST filling of convex polygons, with clipping. * Low-level keyboard handler, ideal for game development. * User-definable image buffer (up to 64K) for faster creation and display of GIF, PCX, and pixel run files. * Additional graphics primitives, including XOR points/lines/boxes in all graphics modes, filled circles and ellipses, and clipped region fill. * Bit maps that don't include transparent colors. * Block transfers between RAM and video memory instead of just video memory to video memory. * Improved ROM text support, including three font sizes (VGA/SVGA) and the ability to display strings relative to any graphics position. * Ability to access up to 1MB video RAM in non-SVGA modes with certain SVGA chipsets (see the READ.ME file for more information about this). * Ability to display PCX images at the position defined in the PCX header instead of only relative to the current graphics position. * Total of 47 new functions. * Support for additional compilers. The release notes provide an overview of most of these new features. For details, refer to the Fastgraph User's Guide and Reference Manual. Please be sure to see the last section of this document, which discusses two important compatibility considerations when migrating Fastgraph 2.xx programs to version 3.0. ------------------------------------------------------------------------------ Summary of New Routines in Fastgraph 3.0 ------------------------------------------------------------------------------ The following routines are new to Fastgraph 3.0. Please see the Fastgraph Reference Manual for full descriptions, including their parameters, return values, and restrictions. FG_BOXW World space version of FG_BOX FG_BOXX Draw hollow rectangle in XOR mode FG_BOXXW World space version of FG_BOXX FG_CIRCLEF Draw a filled circle FG_CIRCLEFW World space version of FG_CIRCLEF FG_DEFPAGES Define extended video pages when using block transfer routines FG_DRAWRELX Draw line in XOR mode relative to graphics position FG_DRAWRXW World space version of FG_DRAWRELX FG_DRAWX Draw line in XOR mode FG_DRAWXW World space version of FG_DRAWX FG_ELLIPSEF Draw a filled ellipse FG_ELLIPSFW World space version of FG_ELLIPSEF FG_FILLPAGE Fill active video page with the current color FG_FLOOD Like FG_PAINT but observes the clipping limits FG_FLOODW World space version of FG_FLOOD FG_FONTSIZE Enable 8x8, 8x14, or 8x16 ROM font (VGA/SVGA only) FG_GETBLOCK Transfer rectangular region from video memory to RAM FG_GETENTRY Get address and type of a physical, virtual, or logical page FG_IMAGEBUF Define address and size of Fastgraph's GIF/PCX file buffer FG_INSIDE Check if a specified point is inside a convex polygon FG_JUSTIFY Define justification settings for FG_PRINT FG_KBINIT Enable or disable the Fastgraph low-level keyboard handler FG_KBTEST Determine if a key is now pressed or released FG_MAKEGIF Create GIF file from rectangular region of active video page FG_MAKEPPR Create PPR file from rectangular region of active video page FG_MAKESPR Create SPR file from rectangular region of active video page FG_MEMORY Return amount of video memory present in kilobytes FG_MOUSEFIN Unhook Fastgraph's XVGA or SVGA mouse handler FG_PAGESIZE Return video page size in bytes FG_POINTX Draw point in XOR mode FG_POINTXW World space version of FG_POINTX FG_POLYFILL Draw filled convex polygon FG_POLYLINE Draw unfilled polygon from one vertex array FG_POLYOFF Define polygon offsets for FG_POLYFILL and FG_POLYLINE FG_PRINT Display hardware characters in screen space FG_PUTBLOCK Transfer rectangular region from RAM to video memory FG_PUTIMAGE Like FG_DRWIMAGE but doesn't check for transparent pixels FG_SETENTRY Set address and type of a physical, virtual, or logical page FG_SHOWGIF Display GIF file FG_SHOWPCX Display PCX file (formerly FG_DISPPCX) FG_SHOWPPR Display packed pixel run (PPR) file FG_SHOWSPR Display standard pixel run (SPR) file FG_SVGAINIT Initialize Fastgraph's SVGA kernel FG_SVGASTAT Return information about the active SVGA chipset FG_SVGAVER Return Fastgraph SVGA kernel version number FG_TCDEFINE Define transparent color number for FG_TCXFER FG_WAITVR Specify if functions wait internally for vertical retrace Note that FG_MAKEGIF, FG_SHOWGIF, and the world space functions are not in Fastgraph/Light. ------------------------------------------------------------------------------ New SVGA Video Modes ------------------------------------------------------------------------------ Six new video modes have been introduced for Fastgraph's SVGA support. These are summarized below: 640x400x256 mode 24 1024x768x256 mode 27 640x480x256 mode 25 800x600x16 mode 28 800x600x256 mode 26 1024x768x16 mode 29 Before you establish an SVGA graphics mode with FG_SETMODE, you must call the FG_SVGAINIT function. This new function initializes Fastgraph's SVGA kernel for a specific SVGA chipset (see the list of supported chipsets in the next section). You can use FG_SVGAINIT to automatically detect the system's SVGA chipset, or you can use a specific chipset. More information about the new SVGA video modes, Fastgraph's SVGA kernel, and the FG_SVGAINIT routine appears in Chapters 2 and 3 of the Fastgraph User's Guide. ------------------------------------------------------------------------------ Supported SVGA Chipsets ------------------------------------------------------------------------------ As different manufacturers developed SVGA cards, they implemented the SVGA features according to their own specifications (each unique implementation is called a "chipset"). This situation arose because of the lack of an SVGA standard. Fastgraph 3.0 will directly support the SVGA chipsets listed in the table below. A "Y" entry means the chipset supports the video mode, and an "N" means it doesn't. The last row of the table shows the amount of video memory required to support each mode. ----------- 256 colors ------------ --- 16 colors --- SVGA chipset 640x400 640x480 800x600 1024x768 800x600 1024x768 ============================================================================== Ahead "A" type Y Y Y N Y Y ------------------------------------------------------------------------------ Ahead "B" type Y Y Y Y Y Y ------------------------------------------------------------------------------ ATI 18800 Y Y Y N Y N ------------------------------------------------------------------------------ ATI 18800-1 Y Y Y N Y Y ------------------------------------------------------------------------------ ATI 28800 Y Y Y Y Y Y ------------------------------------------------------------------------------ Chips & Tech 82c451 Y N N N Y N ------------------------------------------------------------------------------ Chips & Tech 82c452 Y Y N N Y Y ------------------------------------------------------------------------------ Chips & Tech 82c453 Y Y Y Y Y Y ------------------------------------------------------------------------------ Cirrus Logic 5400 series N Y Y Y Y Y ------------------------------------------------------------------------------ Genoa 6000 series Y Y Y N Y Y ------------------------------------------------------------------------------ Oak OTI-067 N Y Y N Y Y ------------------------------------------------------------------------------ Paradise PVGA1a Y Y N N Y N ------------------------------------------------------------------------------ Paradise WD90C00/10 Y Y N N Y Y ------------------------------------------------------------------------------ Paradise WD90C11/30/31 Y Y Y Y Y Y ------------------------------------------------------------------------------ S3 N Y Y Y Y Y ------------------------------------------------------------------------------ Trident 8800 Y Y N N Y Y ------------------------------------------------------------------------------ Trident 8900/8900B/8900C Y Y Y Y Y Y ------------------------------------------------------------------------------ Tseng ET3000 N Y Y N Y Y ------------------------------------------------------------------------------ Tseng ET4000 Y Y Y Y Y Y ------------------------------------------------------------------------------ Video7 Y Y Y Y Y Y ============================================================================== minimum video RAM needed 256 512 512 1MB 256 512 ------------------------------------------------------------------------------ ------------------------------------------------------------------------------ VESA-compatible SVGA Cards ------------------------------------------------------------------------------ The Video Electronics Standards Association (VESA) has assumed the complex task of improving the compatibility of SVGA cards from different companies. Most SVGA cards sold today include VESA compatibility, either directly in ROM or through software drivers. Fastgraph 3.0 provides support for any SVGA card with VESA compatibility. When using VESA compatibility, the VESA BIOS handles all chipset-specific functions such as bank switching. The overhead imposed by the BIOS usually makes the VESA modes slightly slower than using chipset-specific functions directly. For this reason, the FG_SVGAINIT routine lets you specify if you want to give precedence to the chipset-specific SVGA code or to the VESA BIOS. Chipset-specific precedence means FG_SVGAINIT will only use the VESA BIOS if no supported SVGA chipset is found. Conversely, VESA precedence means FG_SVGAINIT will only use the chipset-specific functions if no VESA BIOS is found. VESA implementations for some video cards are more VESA-compatible than others, especially in areas of page flipping and panning. Fastgraph has no way to determine the degree of compatibility for any VESA function. If an SVGA program will include VESA support, we recommend also including a method to select chipset-specific SVGA code. Problematic VESA drivers are beyond the control of Fastgraph, of application programmers, and perhaps most importantly, beyond the control of your program's end users. ------------------------------------------------------------------------------ SVGA Read and Write Banks ------------------------------------------------------------------------------ Accessing video memory on an SVGA is controlled through a banking scheme that maps contiguous 64KB blocks of video memory into a segmented address space. In other words, referencing a specific byte in video RAM requires a bank number and an address offset within that bank. Some SVGA cards provide dual read and write bank registers, while others perform both operations through the same bank register. Fastgraph's FG_COPYPAGE, FG_RESTORE, FG_SAVE, FG_TCXFER, and FG_TRANSFER functions copy rectangular blocks from one part of video memory to another. If an SVGA card provides separate read and write banks, these functions can copy the source region directly to the destination region. However, SVGA cards that employ a single bank register require that these functions copy the source region to an intermediate buffer and then copy the buffer contents to the destination. This makes the block transfer operation slower, especially in 16-color SVGA modes. ------------------------------------------------------------------------------ SVGA Display Pages ------------------------------------------------------------------------------ Most of the SVGA graphics modes include additional video pages if your SVGA card has enough video RAM. The following table shows the number of video pages available in each mode. Mode Number of pages with.... Number Resolution 256KB 512KB 768KB 1MB 24 640x400x256 1 2 3 4 25 640x480x256 0 1 1 2 26 800x600x256 0 1 1 2 27 1024x768x256 0 0 1 1 28 800x600x16 1 2 3 4 29 1024x768x16 0 1 1 2 Some SVGA chipsets restrict what you can do with video pages beyond page 0. Certain chipsets let you access the additional pages but do not let you make them the visual page, while others completely disable some or all of the extra memory in some video modes. A few older chipsets have limitations on page flipping and panning. These items are discussed in the READ.ME file. ------------------------------------------------------------------------------ SVGA Chipset Limitations and Problems ------------------------------------------------------------------------------ This section summarizes the known limitations and problems of the supported SVGA chipsets. The ATI 18800 chipset restricts horizontal panning to four-pixel increments in 256-color SVGA modes. In these modes, FG_PAN will reduce the x position to a multiple of four pixels. The Cirrus Logic 5400 series chipsets have panning problems in the 256-color SVGA modes (25 to 27). Panning to an x coordinate that is not a multiple of four will leave x modulo 4 colums of undefined pixels along the right edge of the video display. The Genoa 6000 series chipsets do not include the ability to set the display start address beyond the 16-bit capability provided by the CRT Controller. This means FG_SETVPAGE is not meaningful in SVGA graphics modes. Further, the FG_PAN screen origin is restricted to the first 64K bytes of video memory in 256-color SVGA modes, and to the first 256K bytes in 16-color SVGA modes. The Genoa 6000 series chipsets restrict horizontal panning to even addresses in video memory in the 1024x768x16 mode (mode 29). This means you can pan only to x coordinates where x modulo 16 is less than 8. The Oak OTI-067 chipset apparently does not include the ability to set the display start address beyond the 16-bit capability provided by the CRT Controller. This means FG_SETVPAGE is not meaningful in SVGA graphics modes. Further, the FG_PAN screen origin is restricted to the first 64K bytes of video memory in 256-color SVGA modes, and to the first 256K bytes in 16-color SVGA modes. The Oak OTI-067 chipset has paging problems in 16-color SVGA modes. Because this chipset supports a maximum of 512K video memory, mode 28 is the only 16-color SVGA mode that is a candidate for additional pages. However, video memory beyond 256K is apparently disabled in this mode. All Paradise chipsets restrict horizontal panning to four-pixel increments in 256-color SVGA modes. In these modes, FG_PAN will reduce the x position to a multiple of four pixels. All S3 chipsets restrict horizontal panning to four-pixel increments in 256- color SVGA modes. In these modes, FG_PAN will reduce the x position to a multiple of four pixels. The Trident 8800 chipsets use a unique pixel doubling technique in the 256- color SVGA modes. For example, the 640 x 400 mode (mode 24) actually uses a 1280 x 400 video frame. This means a multisync monitor is required to use the two available 256-color modes (24 and 25). Note that this "feature" only applies to the Trident 8800 and NOT the 8900 family. Video cards based on the Trident 8900, 8900B, and 8900C chipsets all have problems accessing video memory beyond 512K in 16-color SVGA modes. This means a 1MB Trident card has two pages instead of four in mode 28, and one page instead of two in mode 29. At least one video card based on the Trident 8900C chipset has problems accessing video memory beyond 512K in the 640x400 and 640x480 256-color SVGA modes (in addition to the similar problem in the 16-color SVGA modes for all Trident chipsets). Such cards would have two video pages instead of four in modes 24 and 28, and one page instead of two in modes 25 and 29. Note that this problem does not apply to all Trident 8900C cards; the problem has only been reported on one 8900C-based video card. Video cards based on the Video7 HT208 chipset (i.e., the Video7 VGA 1024i) have panning problems in all SVGA modes. ------------------------------------------------------------------------------ XVGA and SVGA Mouse Support ------------------------------------------------------------------------------ This release offers mouse support for the extended VGA (XVGA) graphics video modes (modes 20 to 23) and SVGA graphics modes (24 to 29). In these modes, Fastgraph displays the mouse cursor through an interrupt handler that is activated whenever the mouse moves. The handler is installed when you call FG_MOUSEINI in modes 20 to 29. If you do not disable this handler before your program exits, strange things will happen. More specifically, characters may be invisible, or your system may hang upon attempting a disk access. Obviously, these are problems to avoid. The FG_MOUSEFIN routine removes Fastgraph's mouse interrupt handler previously installed with FG_MOUSEINI. You should call FG_MOUSEFIN just before restoring the original video mode, as illustrated below: fg_mousefin(); fg_setmode(old_mode); fg_reset(); /* now exit to DOS */ Note that calling FG_MOUSEFIN is required only in XVGA and SVGA graphics modes. Calling it in other video modes is not applicable, though it causes no problems. In the standard VGA/MCGA 256-color mode (mode 19), white pixels in the mouse cursor are displayed in color 15. This is inconsistent with other graphics modes, where the white pixels are displayed in the highest-numbered color value available in that mode. Fastgraph corrects this inconsistency in modes 20 to 27 by displaying white mouse cursor pixels in color 255. Like color 15, color 255 is white by default. This allows you to redefine color 15 in your 256-color applications without interfering with the mouse cursor colors. ------------------------------------------------------------------------------ Low-Level Keyboard Handler ------------------------------------------------------------------------------ Fastgraph 3.0 includes a new low-level keyboard handler that replaces the BIOS keyboard handler. Fastgraph's keyboard handler intercepts keystrokes ahead of the BIOS and thus eliminates the annoying beep that sounds upon filling the BIOS keyboard buffer. The low-level keyboard handler should be especially well-suited to game development because it increases keyboard responsiveness in high-speed action games. However, when the low-level keyboard handler is enabled, it is not possible to use FG_GETKEY, FG_INTKEY, or any third party functions that use BIOS or DOS services to access the keyboard. For this reason, a program that enables the low-level keyboard handler must disable it before exiting to DOS. The low-level keyboard handler can be enabled and disabled at any time. The FG_KBINIT routine is provided for this purpose. When it is enabled, you can use the FG_KBTEST routine to check if keys are currently pressed or released. FG_KBTEST provides the only mechanism for accessing the keyboard when the low-level handler is enabled. Please see Chapter 14 of the Fastgraph User's Guide for a full description of the low-level keyboard handler. ------------------------------------------------------------------------------ New FG_SHOWPCX Flag Bits ------------------------------------------------------------------------------ FG_SHOWPCX has two new bits defined in the flags parameter: Bit 1 0 = display image at position indicated in PCX header 1 = display image at current graphics position Bit 2 0 = read PCX image data from the PCX file 1 = assume PCX image data is in the FG_IMAGEBUF buffer In Fastgraph 2.xx, PCX images were always displayed relative to the current graphics position. This behavior is achieved in Fastgraph 3.0 by setting bit 1 in the flags parameter. If bit 1 is zero, the image will be displayed at the location specified in the PCX header. As of Fastgraph 3.03, bit 2 in the flags parameter defines the source of the PCX image data. If bit 2 is zero, FG_SHOWPCX displays the image directly from the PCX file (this was the only available method of displaying PCX images in Fastgraph 3.02 and before). If bit 2 is set, FG_SHOWPCX assumes the image data is in the FG_IMAGEBUF buffer. Note that the FG_IMAGEBUF buffer has a maximum size of 64K bytes, so this feature is applicable only if the size of the GIF or PCX file is 64K bytes or less. The following program fragment shows how to display PCX image data stored in the FG_IMAGEBUF buffer. The same technique can be used to display GIF image data from the FG_IMAGEBUF buffer if we use FG_SHOWGIF instead of FG_SHOWPCX. static char far buffer[40000]; FILE *stream; int file_size; stream = fopen("TEST.PCX","rb"); file_size = (int)(filelength(fileno(stream))); fread(buffer,1,file_size,stream); fclose(stream); fg_imagebuf(buffer,file_size); fg_showpcx("",4); In this example, there is a 40,000-byte array that we'll use as the image buffer. Note that we specify the actual PCX file length, not the array size, as the buffer size when we call FG_IMAGEBUF. It is extremely important that this be the case when displaying GIF or PCX data stored in the image buffer. Note also how we must include a "place holder" parameter where the PCX file name is normally passed to FG_SHOWPCX. While any string can be specified for this purpose, we recommend using the null string as in the above example. ------------------------------------------------------------------------------ Some Notes About Polygons ------------------------------------------------------------------------------ Fastgraph's new polygon fill function (FG_POLYFILL) fills convex polygons. A polygon is convex if any horizontal line drawn through the polygon crosses the left edge exactly once and the right edge exactly once (excluding horizontal and zero-length edge segments). Note that this definition includes shapes that are not convex in the traditional sense. In addition, any non-convex polygon can be decomposed into two or more convex polygons. The filled convex polygon is a fundamental tool of three-dimensional computer graphics. A common practice is to build an image or object from several adjacent or connecting polygons. Such polygons typically overlap at one or more edges. For instance, the coordinates defining the right edge of one polygon may also define the left edge of another polygon immediately to its right. For an overall image to appear correct, its component polygons must fit together correctly. Fastgraph's FG_POLYFILL function applies the following rules to handle overlapping polygon edges: 1) Points located exactly on non-horizontal edges are drawn only if the polygon's interior is directly to the right. 2) Points located exactly on horizontal edges are drawn only if the polygon's interior is directly below them. 3) A vertex is drawn only if all lines ending at that point meet the above two conditions. These three rules ensure that no pixel is drawn more than once when filling adjacent polygons. However, they may not be suitable for displaying polygons that are not adjacent because some of the pixels on the polygon's edge will not be included. If this is an issue, first draw the filled polygon with FG_POLYFILL, then draw an unfilled polygon having the same vertices with the FG_POLYLINE function. Both FG_POLYFILL and FG_POLYLINE honor the current clipping limits. Refer to Chapter 6 of the Fastgraph User's Guide for more information about Fastgraph's new polygon routines. ------------------------------------------------------------------------------ Extended Video Pages ------------------------------------------------------------------------------ One of the more frequent technical support questions we receive is "I have one megabyte of memory on my video card, why can I only use the first 256K?". The answer is simple: the standard EGA and VGA modes have no way to address video memory beyond 256K. Accessing this memory requires SVGA bank switching techniques. This is analogous to the fact that you might have four megabytes of RAM on your system, but without an EMS/XMS memory manager, a DOS extender, or the like, all that memory won't do much good. Unfortunately, not all SVGA chipsets allow bank switching in non-SVGA video modes. For those that do, however, Fastgraph 3.0 includes a last-minute addition called EXTENDED VIDEO PAGES that provide access to all memory on the video card in modes 13 to 23 instead of restricting access to the first 256K. This means, for example, that a 1MB SVGA card will allow 32 physical pages in mode 13 rather than the usual 8 pages. At this time, extended pages are available with the following SVGA chipsets: Ahead B (except in mode 19) ATI 28800 (except in mode 19) Paradise WD90C11/WD90C30/WD90C31 Tseng ET4000 Although extended pages are used in non-SVGA graphics modes, the method of accessing video memory above 256K is specific to each SVGA chipset. Thus, you must initialize Fastgraph's SVGA kernel (with FG_SVGAINIT) before you can use extended pages. When writing applications that use extended video pages, you should make sure they are available on the active SVGA chipset and that there is enough video memory for the number of pages required. First, verify that FG_SVGAINIT successfully initializes the SVGA kernel. If so, use the FG_SVGASTAT routine to see if the SVGA chipset supports extended pages. Finally, use FG_MEMORY to insure that enough video memory is available for the number of video pages needed. The following table shows the number of video pages available in modes 13 to 23. Number of Pages With... Mode 256K 512K 1MB 13 8 16 32 14 4 8 16 15 2 4 8 16 2 4 8 17 2 4 8 18 2 4 8 19 4 8 16 20 4 8 16 21 2 4 8 22 4 8 16 23 2 4 8 Note that when extended pages are not enabled, the video mode has the number of physical video pages listed in the 256K column. The exception to this is mode 19, which has only one physical page unless extended pages are enabled. Some video modes do not provide the listed number of full video pages. For example, modes 17 and 18 normally have two video pages -- one full 640x480 page (page 0) and one partial 640x320 page (page 1). For extended pages, Fastgraph uses a page numbering scheme that maintains consistency with its standard page numbering. That is, when extended pages are available and mode 17 or 18 is used on a 1MB video card, the page numbers will range from 0 to 7, with the even-numbered pages being full pages and the odd-numbered pages being partial 640x320 pages. Similarly, in mode 22 pages 3, 7, 11, and 15 are partial (320x80); in mode 23 odd-numbered pages are partial (320x320). See the Fastgraph User's Guide for more information on partial video pages. When you use Fastgraph's block transfer routines (FG_COPYPAGE, FG_RESTORE, FG_SAVE, FG_TCXFER, and FG_TRANSFER) with extended pages, you must also use the new FG_DEFPAGES routine to define the source and destination video pages. This is needed because the two pages may reside in different SVGA banks, and bank switching is not performed in Fastgraph's non-SVGA code. The additional overhead of having the block transfer routines determine the bank numbers is not necessary in all cases (see below), and it would also impact the block transfer routines when extended pages are not being used. Before you use one of the block transfer routines, you must call FG_DEFPAGES, passing it the source and destination page numbers. FG_DEFPAGES determines the SVGA bank numbers in which the source and destination pages reside and then enables the corresponding banks for reading and writing, respectively. These banks remain in effect until you define new ones with FG_DEFPAGES or FG_SETPAGE, so you may not need to call FG_DEFPAGES before every call to a block transfer routine. The following table shows the bank numbers for each video page in each 16-color mode that supports extended pages. ---------- Pages in ---------- Mode Bank 0 Bank 1 Bank 2 Bank 3 13 0-7 8-15 16-23 24-31 14 0-3 4-7 8-11 12-15 15 0-1 2-3 4-5 6-7 16 0-1 2-3 4-5 6-7 17 0-1 2-3 4-5 6-7 18 0-1 2-3 4-5 6-7 20 0-3 4-7 8-11 12-15 21 0-1 2-3 4-5 6-7 22 0-3 4-7 8-11 12-15 23 0-1 2-3 4-5 6-7 In mode 19, each of the 16 possible pages is in its own SVGA bank. That is, page 0 is in bank 0, page 1 is in bank 1, and so forth. The following code calls FG_DEFPAGES only when needed in mode 13, where each group of 8 pages resides in its own SVGA bank. FG_SETMODE enables bank 0 for reading and writing, so we don't need to call FG_DEFPAGES until we reference a page in one of the other banks (page 10 in this example). fg_svgainit(0); fg_setmode(13); /* enables bank 0 for reading and writing */ fg_copypage(0,1); fg_copypage(0,2); fg_defpages(0,1); /* page 10 is in bank 1 */ fg_copypage(2,10); fg_defpages(1,1); /* page 15 is in bank 1 */ fg_copypage(10,15); fg_setpage(0); /* enables bank 0 for reading and writing */ fg_erase(); fg_copypage(0,3); fg_defpages(1,0); /* page 15 is in bank 1 */ fg_copypage(15,4); FG_DEFPAGES has no effect unless extended pages are enabled. Most mouse drivers know nothing about SVGA bank switching and non-standard video modes (that's why Fastgraph must hook its own mouse cursor control handlers into the mouse driver in XVGA and SVGA modes). As Fastgraph still programs the mouse driver for cursor control in modes 13 to 19, it is only possible to display the mouse cursor on video pages in the first SVGA bank (bank 0) in these modes. Note that this does not apply to modes 20 to 23, where Fastgraph controls the mouse cursor through its own handlers. Some SVGA chipsets do not reset the read and write bank numbers back to zero when establishing a non-SVGA video mode. When a mode set operation clears video memory, such chipsets will clear the first video page in whatever write bank was last selected. While FG_SETMODE does set the read and write banks to zero when extended pages are available, it cannot do this before setting the video mode, which is what normally would clear the screen. This may result in artifacts on page 0 after calling FG_SETMODE. The easiest way around this problem is to call FG_DEFPAGES(0,0) before restoring the original video mode in programs that use extended pages. Even this, however, does not clear video memory after a mode set when using extended pages with some SVGA chipsets. We therefore recommend calling FG_ERASE immediately after calling FG_SETMODE when using extended pages. Extended pages may be resized (with FG_RESIZE) just as the standard video pages may in modes 13-18 and 20-23. However, the resulting pages must not cross SVGA bank boundaries. In mode 20, for instance, you normally have four 320x200 pages in each bank. You could change the video page size to 640x400, thereby having four larger pages, one in each bank. You could not, however, resize video memory to two 640x800 pages, as each page would span two banks. Again, we developed extended pages as a last-minute addition to Fastgraph because we've had so many requests for this feature. Please bear in mind that the implementation of extended pages in Fastgraph 3.0 is the first attempt at a solution to our customer's needs. In the future, we hope to find ways to support more SVGA chipsets and remove some of the limitations, especially the restriction on displaying the mouse cursor beyond bank zero. ------------------------------------------------------------------------------ Optimizations, Improvements, and Corrections to Existing Routines ------------------------------------------------------------------------------ The performance of several existing Fastgraph functions has been improved in version 3.0. The most notable of these are FG_DRWIMAGE (in 16-color modes) and FG_PAINT, both of which provide a performance improvement on the order of 20% to 25%. The FG_TEXT routine no longer uses the BIOS in modes 13 to 18. This change greatly improves the speed of FG_TEXT in these modes. It also eliminates the problem where characters were displayed in the wrong colors when a character's background cell contained pixels of different colors. The FG_PAN routine now supports one-pixel horizontal panning in modes 19 to 23. Previously panning was restricted to four-pixel increments in these video modes. Fastgraph's mouse support routines no longer require the presence of the mouse driver's EGA Register Interface Library (RIL) when using the mouse in modes 17 and 18. Fastgraph will still use the RIL if it is present, as many mouse drivers rely on the RIL for proper operation. For mouse drivers such as the OS/2 mouse driver that do not use the RIL in these modes, Fastgraph now programs the VGA registers directly, just as when the mouse isn't used. In modes 20 and 21, the video page offsets were changed to prevent the mouse cursor save area from conflicting with displayable video memory. This would cause problems if the last video page (page 3 in mode 20, page 1 in mode 21) was the visual page and you moved the mouse into the lower right corner of the screen. If your code relies on specific page offsets in these modes, the new page sizes are 3E80 hex for mode 20 and 7D00 hex for mode 21. The values in Fastgraph 2.xx were 4000 and 8000 hex respectively. The FG_BESTMODE routine will now propose mode 20 instead of mode 19 when checking for a 320 x 200 graphics mode on VGA systems. The order of the two FG_BOXDEPTH parameters has been corrected (they were transposed in Fastgraph 2.xx). The masking map routines (FG_CLIPMASK, FG_DRAWMASK, FG_FLIPMASK, and FG_REVMASK) now work in all video modes. The CLIP utility no longer requires two video pages, which means it now supports modes 17, 18, and 23. ------------------------------------------------------------------------------ New Turbo Pascal Unit Files ------------------------------------------------------------------------------ Fastgraph 2.xx uses two unit files, FGTP.TPU and FGTPX.TPU. FGTP.TPU is the primary Fastgraph unit, while FGTPX.TPU contains the extended Fastgraph routines listed in Appendix D of the Fastgraph User's Guide. Borland Pascal and Turbo Pascal restrict the total size of all code segments in a unit file 65,520 bytes. With the introduction of the SVGA support and other new features in Fastgraph 3.0, the size of the FGTP.TPU unit file would have exceeded this limit. For this reason, the FGTP.TPU file has been split into several unit files. Fastgraph routines in FGBITMAP.TPU: FG_CLIPMASK FG_FLIPMASK FG_IMAGEBUF FG_REVIMAGE FG_CLPIMAGE FG_FLPIMAGE FG_IMAGESIZ FG_REVMASK FG_DRAWMASK FG_GETBLOCK FG_PUTBLOCK FG_DRWIMAGE FG_GETIMAGE FG_PUTIMAGE Fastgraph routines in FGGIF.TPU: FG_MAKEGIF FG_SHOWGIF Fastgraph routines in FGMISC.TPU: FG_BUTTON FG_INTKEY FG_MOUSEPOS FG_SETCAPS FG_CAPSLOCK FG_KBINIT FG_MOUSEPTR FG_SETNUM FG_CURSOR FG_KBTEST FG_MOUSESPD FG_SOUND FG_GETCLOCK FG_MEASURE FG_MOUSEVIS FG_SOUNDS FG_GETKEY FG_MEMAVAIL FG_MUSIC FG_SUSPEND FG_GETXJOY FG_MOUSEBUT FG_MUSICB FG_VOICE FG_GETYJOY FG_MOUSECUR FG_NUMLOCK FG_VOICES FG_HUSH FG_MOUSEFIN FG_PLAYING FG_WAITFOR FG_HUSHNEXT FG_MOUSEINI FG_QUIET FG_WAITKEY FG_INITJOY FG_MOUSELIM FG_RESUME FG_INTJOY FG_MOUSEMOV FG_SCRLOCK Fastgraph routines in FGPCX.TPU: FG_MAKEPCX FG_PCXHEAD FG_PCXMODE FG_SHOWPCX Fastgraph routines in FGPR.TPU: FG_DISPFILE FG_DISPLAYP FG_MAKESPR FG_SHOWSPR FG_DISPLAY FG_MAKEPPR FG_SHOWPPR Fastgraph routines in FGSVGA.TPU: FG_DEFPAGES FG_SVGAINIT FG_SVGASTAT FG_SVGAVER FG_MEMORY Any Fastgraph routine that uses the world space coordinate system is in the file FGWORLD.TPU (this was formerly FGTPX.TPU). All other Fastgraph routines are in the FGMAIN.TPU unit file. The above lists appear in Appendix E of the Fastgraph User's Guide. ------------------------------------------------------------------------------ Converting Applications to Fastgraph 3.0 ------------------------------------------------------------------------------ Only two features in Fastgraph 2.xx are not upwardly compatible with version 3.0. The first applies only to Borland Pascal and Turbo Pascal, while the second applies to all supported compilers. As described in the previous section, it was necessary to split the FGTP.TPU unit of Fastgraph 2.xx into several unit files. Additionally, the FGTPX.TPU unit is now called FGWORLD.TPU. Pascal programmers must replace the FGTP and FGTPX unit names in the USES statement with FGMAIN and FGWORLD, respectively. If your programs call any of the routines in the other new units, you must add the appropriate unit names to the USES statement as well. Please see the preceding section of this document or Appendix E of the Fastgraph User's Guide for lists of the Fastgraph routines in each unit file. The other change pertains to the new FG_SHOWPCX function, which replaces the FG_DISPPCX function of earlier versions (the function was renamed to avoid confusion with the pixel run display routines, which all have names of the form FG_DISPxxxx). PCX image positioning will generally not be an issue for full-screen PCX files because the PCX header typically defines their upper left corner at the screen origin, which is where you'd move to display a full-screen image anyway. However, if a PCX file is smaller than the screen resolution and you want to override the image positioning in the PCX header, you must define a new FG_SHOWPCX flags argument in which bit 1 is set. That is, the Fastgraph 2.xx call FG_DISPPCX(filename,0) is equivalent to FG_SHOWPCX(filename,2). Similarly, FG_DISPPCX(filename,1) is equivalent to FG_SHOWPCX(filename,3). Note that C programmers can use the following preprocessor directive to make an old FG_DISPPCX call compatible with the new FG_SHOWPCX function. #define fg_disppcx(a,b) fg_showpcx(a,b|2)