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HGRAPH.LIB V1.01 HGRAPH.LIB HGRAPH.LIB is a collection of subroutines to give Hercules HGRAPH.LIB graphics capability to MSC and QuickC and are better than MSC's & QuickC's in that they just have to be linked in. They do not require a driver to be loaded like with MSC & QC. This is version 1.01 release of these routines. They have been compiled and tested only on a Leading Edge Model "D" which has a hercules clone card in it. The only known difference between this clone card and a real Hercules card is that this clone fakes the light pen port (if you try to read its lightpen port for the graphics state it always returns text mode). INTRODUCTION INTRODUCTION The lib includes clearing and non-clearing subroutines to switch between text and graphics modes. A clear page and show page for clearing and switching between the two graphics pages. A pixel routine to read, write, and toggle a pixel. Two line subroutines one to draw a line in either white or black and one to toggle a line. And three string writing functions, one that treats the graphics screen as 43 rows and 90 columns while the other two let you define the upper left corner of where the string is to be written. There are also a save screen and a restore screen, similar to BASIC's BSAVE & BLOAD and a print screen routine for Epson printers. All the routines that write to the graphics screen are written in MSC MASM 5.1 for greater speed. The screen dump routines do their own buffering also for this reason. USAGE USAGE There is now a XHGRAPH.LIB library for each memory model, XHGRAPH.LIB _ where X is the model (S, M, C, L). So you must link with the X S M C L _ library of the same type model as the program was compiled with. The only restriction in using the libraries is that You must call hgraph_init() before using any of the other routines. hgraph_init() i HGRAPH.LIB V1.01 HGRAPH.LIB The rest of the documentation is a list of library routines and what they do. The appendix holds a couple of examples and a few programing tips. The libraries are release into the public domain with the following restrictions: 1) That they only be transmitted from one person to the next in a complete and unmodified form. 2) That the libraries, documentation, and algorithms remain copy righted to me, Steven P. Murphy. 3) No warranties are expressed or implied. I am not responsible for the use, misuse, or abuse of these libraries. Any comments, suggestions, or bugs should be reported to: Steven P. Murphy 6581 Bing St. San Diego, CA 92115-6715 or murphys@cod.nosc.mil (USENET) And for those you who really like HGRAPH donations will not be refused. ii HGRAPH.LIB V1.01 HGRAPH.LIB All the routines treat the graphics screen as a grid of dots except hwrite and hstr which treat it as a set of rows and ______ ____ columns. For all the routines except hwrite and hstr the screen ______ ____ dimension are as follows: 0 719 0 ----------------------------------------------- | | | | | | | | | | | | | | | | | | | | | | | | 347 ----------------------------------------------- for hwrite and hstr the screen is: ______ ____ 0 89 0 ----------------------------------------------- | | | | | | | | | | | | | | | | | | | | | | | | 42 ----------------------------------------------- The conversion from rows & columns to dots is each row is eight dots height and each column is eight dots wide. iii HGRAPH.LIB V1.01 HGRAPH.LIB TABLE OF CONTENTS TABLE OF CONTENTS h_get_scrn . . . . . . . . . . . . . . . . . . 1 h_sav_scrn . . . . . . . . . . . . . . . . . . 2 hbox . . . . . . . . . . . . . . . . . . 3 hchar . . . . . . . . . . . . . . . . . . 4 hchar2 . . . . . . . . . . . . . . . . . . 5 hclearpg . . . . . . . . . . . . . . . . . . 6 hellipse . . . . . . . . . . . . . . . . . . 7 herc_there . . . . . . . . . . . . . . . . . . 8 hgmode . . . . . . . . . . . . . . . . . . 9 hgmode_nc . . . . . . . . . . . . . . . . . . 10 hgraph_init . . . . . . . . . . . . . . . . . . 11 hline . . . . . . . . . . . . . . . . . . 12 hpixel . . . . . . . . . . . . . . . . . . 13 hscdump . . . . . . . . . . . . . . . . . . 14 hscdump2 . . . . . . . . . . . . . . . . . . 15 hshowpg . . . . . . . . . . . . . . . . . . 16 hstr . . . . . . . . . . . . . . . . . . 17 htmode . . . . . . . . . . . . . . . . . . 18 htmode_nc . . . . . . . . . . . . . . . . . . 19 hwrite . . . . . . . . . . . . . . . . . . 20 hxchar . . . . . . . . . . . . . . . . . . 21 hxchar2 . . . . . . . . . . . . . . . . . . 22 hxline . . . . . . . . . . . . . . . . . . 23 hxstr . . . . . . . . . . . . . . . . . . 24 Appendix A . . . . . . . . . . . . . . . . . . 25 cornucopia.c . . . . . . . . . . . . . . . . 26 demo1.c . . . . . . . . . . . . . . . . 27 Appendix B . . . . . . . . . . . . . . . . . . 28 programing ideas . . . . . . . . . . . . . . 29 iv HGRAPH.LIB V1.01 HGRAPH.LIB H_GET_SCRN H_GET_SCRN Summary _______ #include <hgraph.h> Contains function prototypes int h_get_scrn(file_name); h_get_scrn _________ char *file_name /* name of file to get the */ _________ /* image from */ Description ___________ Opens file_name for reading in binary mode and copies _________ 32K bytes from file_name to graphics page 0 or 1 _________ according to the current value of HGPAGE (see HGPAGE hgraph_init). Return Value ____________ H_get_scrn returns a -1 if it could not successfully H_get_scrn open file_name other wise it will return a 0. _________ See Also ________ h_sav_scrn 1 HGRAPH.LIB V1.01 HGRAPH.LIB H_SAV_SCRN H_SAV_SCRN Summary _______ #include <hgraph.h> Contains function prototypes int h_sav_scrn(file_name); h_sav_scrn _________ char *file_name /* name of file to store */ _________ /* image in */ Description ___________ Opens file_name for writing in binary mode and copies _________ 32K bytes from graphics page 0 or 1 according to the current value of HGPAGE (see hgraph_init). HGPAGE Return Value ____________ H_sav_scrn returns a -1 if it could not successfully H_sav_scrn open file_name other wise it will return a 0. _________ See Also ________ h_get_scrn 2 HGRAPH.LIB V1.01 HGRAPH.LIB HBOX HBOX Summary _______ #include <hgraph.h> Contains function prototypes void hbox(color, trow, lcol, brow, rcol); hbox _____ ____ ____ ____ ____ int color; /* should only be a 1 or 0 */ _____ int trow; /* toprow 0 through 347 */ ____ int lcol; /* left column 0 through 718 */ ____ int brow; /* bottom row 1 through 348 */ ____ int rcol; /* right column 1 through 719 */ ____ Description ___________ Draws a box on page 0 or 1 according to the current value of HGPAGE (see hgraph_init). Hbox calls hline HGPAGE Hbox hline four time arranging the arguments each time so that a box is drawn where (trow, lcol) defines the upper left ____ ____ corner and (brow, rcol) is the lower right. Hbox does Hbox ____ ____ no bounds checking so bad ranges will produce weird results. Return Value ____________ There is no return value. See Also ________ hline 3 HGRAPH.LIB V1.01 HGRAPH.LIB HCHAR HCHAR Summary _______ #include <hgraph.h> Contains function prototypes void hchar(x, y, string, attrib, count); hchar _ _ ______ ______ _____ int x; /* 0 through 719 */ _ int y; /* 0 through 347 */ _ char *string; /* ASCII 0 through 127 */ ______ char attrib; /* HGNORM or HGINVS */ HGNORM HGINVS ______ int count; /* number of chars in string */ _____ ______ Description ___________ Writes the upper left most corner of the string pointed to by string at the coordinates given after each ______ character has been XORed with attrib. Hchar writes to Hchar ______ the graphics page according to the current value of HGPAGE (see hgraph_init). There is no bounds checking HGPAGE done on x and y so numbers outside of range will give _ _ unknown results (probably not good). Hchar uses the Hchar IBM PC/XT/AT ROM character table. This table only has ASCII characters 0 through 127, values outside this range will give garbage. The attrib is xor with the ______ character's bits on each scan line, values other than HGNORM (normal) and HGINVS (inverse) will just produce HGNORM HGINVS odd patterns. Count tells hchar how many of string's hchar _____ ______ characters to plot. MSC regular run-time LIB has a functions strlen() and gcvt(), strlen() will produce a correct count and gcvt() will convert numbers to a _____ string. Return Value ____________ There is no return value. See Also ________ hchar2, hstr, hwrite, hxchar, hxchar2, hxstr MSC's or QuickC's strlen() and gcvt() 4 HGRAPH.LIB V1.01 HGRAPH.LIB HCHAR2 HCHAR2 Summary _______ #include <hgraph.h> Contains function prototypes void hchar2(x, y, string, attrib, count); hchar2 _ _ ______ ______ _____ int x; /* 0 through 719 */ _ int y; /* 0 through 347 */ _ char *string; /* ASCII 0 through 127 */ ______ char attrib; /* HGNORM or HGINVS */ HGNORM HGINVS ______ int count; /* number of chars in string */ _____ ______ Description ___________ Writes the upper left most corner of the string pointed to by string at the coordinates given after each ______ character has been XORed with attrib. Hchar2 writes to Hchar2 ______ the graphics page according to the current value of HGPAGE (see hgraph_init). There is no bounds checking HGPAGE done on x and y so numbers outside of range will give _ _ unknown results (probably not good). Hchar2's Hchar2 character table only has ASCII characters 0 through 127, values outside this range will give garbage. The attrib is xor with the character's bits on each scan ______ line, values other than HGNORM (normal) and HGINVS HGNORM HGINVS (inverse) will just produce odd patterns. Count tells _____ hchar2 how many of string's characters to plot. MSC hchar2 ______ regular run-time LIB has a functions strlen() and gcvt(), strlen() will produce a correct count and _____ gcvt() will convert numbers to a string. Return Value ____________ There is no return value. See Also ________ hchar, hstr, hwrite, hxchar, hxchar2, hxstr MSC's or QuickC's strlen() and gcvt() 5 HGRAPH.LIB V1.01 HGRAPH.LIB HCLEARPG HCLEARPG Summary _______ #include <hgraph.h> Contains function prototypes void hclearpg(void); hclearpg Description ___________ Clears graphics page 0 or 1 according to the current value of HGPAGE (see hgraph_init). HGPAGE Return Value ____________ There is no return value. See Also ________ hgmode, hgmode_nc 6 HGRAPH.LIB V1.01 HGRAPH.LIB HELLIPSE HELLIPSE Summary _______ #include <hgraph.h> Contains function prototypes void hellipse(color, x, y, r); hellipse Description ___________ Draws and ellipse on graphics page 0 or 1 according to the current value of HGPAGE (see hgraph_init) centered HGPAGE at (x, y) with a radius of r. the ellipse will have an _ _ _ aspect ratio of the current value of (int) HGRATIO. If HGRATIO the ratio is < 2 the major axis will be vertical, if it is > 2 the major axis will be horizontal, and if HGRATIO = 2 hellipse will produces the closes it can to HGRATIO hellipse a circle. no bounds checking is done if any part of the ellipse is off the screen weird things may happen. Return Value ____________ There is no return value See Also ________ 7 HGRAPH.LIB V1.01 HGRAPH.LIB HERC_THERE HERC_THERE Summary _______ #include <hgraph.h> Contains function prototypes int herc_there(void); herc_there Description ___________ First it tests for a mono display adapter, if there is one it then watches port 3BA (hex) for a fixed time to see if bit 7 goes high. If bit 7 does go high it then pushes a 3 out port 3BF (hex) to turn on the second page of the herc card. Now it checks for memory in the second page. If this check is good it's a herc other wise it's just a funny mono card. Before it returns it pushes a 0 out port 3BF to return a herc card to diagonal mode. Return Value ____________ Herc_there returns a one if both of the above test are Herc_there true and a zero if either is false. (I have tested this with my clone card, an EGA, a CGA, and a mono adapter, it worked correctly in all cases.) See Also ________ 8 HGRAPH.LIB V1.01 HGRAPH.LIB HGMODE HGMODE Summary _______ #include <hgraph.h> Contains function prototypes void hgmode(void); hgmode Description ___________ Sets graphics mode, clears graphic pages 0 and 1 then switches to graphics page 0. Return Value ____________ There is no return value. See Also ________ hgmode_nc 9 HGRAPH.LIB V1.01 HGRAPH.LIB HGMODE_NC HGMODE_NC Summary _______ #include <hgraph.h> Contains function prototypes void hgmode_nc(void); hgmode_nc Description ___________ Sets graphics mode, does not clears graphic pages 0 and ________ 1 then switches to graphics page 0. Return Value ____________ There is no return value. See Also ________ hgmode 10 HGRAPH.LIB V1.01 HGRAPH.LIB HGRAPH_INIT HGRAPH_INIT Summary _______ #include <hgraph.h> Contains function prototypes void hgraph_init(void); hgraph_init Description ___________ Initializes the necessary global variables for HGRAPH.LIB. These variables are: int HGPAGE; /* current graphics page, used by all */ HGPAGE ___ /* the library routines */ char HGATRB; /* character attribute for hwrite */ HGATRB hwrite int HGRATIO; /* aspect ratio for hellipse */ HGRATIO hellipse The initial values for are HGPAGE = 1, HGATRB = 0x00, HGPAGE HGATRB and HGRATIO = 2. HGPAGE should only be 1 or 0 if it is HGRATIO HGPAGE set to some value other than these two all the routine will default it to 1. HGATRB should only be HGNORM or HGATRB HGNORM HGINVS (defined in hgraph.h) other values will just HGINVS cause the print to look funny. HGRATIO should be a HGRATIO positive int, 0 will cause it to draw a horizontal line, and a negative will hellipse to crash. Return Value ____________ There is no return value. See Also ________ 11 HGRAPH.LIB V1.01 HGRAPH.LIB HLINE HLINE Summary _______ #include <hgraph.h> Contains function prototypes void hline(function, x0, y0, x1, y1); hline ________ __ __ __ __ int function; /* 0 - write pixels in black */ ________ /* 1 - write pixels in white */ int x0; /* 0 through 719 */ __ int y0; /* 0 through 347 */ __ int x1; /* 0 through 719 */ __ int y1; /* 0 through 347 */ __ Description ___________ The default for function is 1, so if hline is called hline ________ with function not equal to those listed you get ________ function 1. The graphics page is set according to the ________ current value of HGPAGE (see hgraph_init). There is no HGPAGE bounds checking done on x0, x1, y0, or y1 so numbers __ __ __ __ outside of range will give unknown results (probably not good). Return Value ____________ There is no return value. See Also ________ hxline 12 HGRAPH.LIB V1.01 HGRAPH.LIB HPIXEL HPIXEL Summary _______ #include <hgraph.h> Contains function prototypes void hpixel(function, x, y); hpixel ________ _ _ int function; /* 0 - write pixel in black */ ________ /* 1 - write pixel in white */ /* 2 - toggle pixel */ /* 3 - read pixel */ int x; /* 0 through 719 */ _ int y; /* 0 through 347 */ _ Description ___________ The default for function is 2, so if hpixel is called hpixel ________ with function not equal to those listed you get ________ function 2. The pixel is plotted on the graphics page ________ according to the current value of HGPAGE (see HGPAGE hgraph_init). There is no bounds checking done on x _ and y so numbers outside of range will give unknown _ results (probably not good). Return Value ____________ The return value is the status the pixel was set to by any of the four functions. So hpixel while always hpixel ________ return a 0 (for black) or a 1 (for white). See Also ________ 13 HGRAPH.LIB V1.01 HGRAPH.LIB HSCDUMP HSCDUMP Summary _______ #include <hgraph.h> Contains function prototypes void hscdump(void); hscdump Description ___________ Dumps graphics page 0 or 1, according to the current value of HGPAGE (see hgraph_init), to an Epson or HGPAGE compatible printer. Each line is double struck to improve the clarity. Return Value ____________ There is no return value. See Also ________ hscdump2 14 HGRAPH.LIB V1.01 HGRAPH.LIB HSCDUMP2 HSCDUMP2 Summary _______ #include <hgraph.h> Contains function prototypes void hscdump2(void); hscdump2 Description ___________ Dumps graphics page 0 or 1, according to the current value of HGPAGE (see hgraph_init), to an Epson or HGPAGE compatible printer. Each line is only single struck to improve the speed. Return Value ____________ There is no return value. See Also ________ hscdump 15 HGRAPH.LIB V1.01 HGRAPH.LIB HSHOWPG HSHOWPG Summary _______ #include <hgraph.h> Contains function prototypes void hshowpg(void); hshowpg Description ___________ Set graphics page 0 or 1, according to the current value of HGPAGE (see hgraph_init), to the currently HGPAGE displayed page. Return Value ____________ There is no return value. See Also ________ hgmode, hgmode_nc 16 HGRAPH.LIB V1.01 HGRAPH.LIB HSTR HSTR Summary _______ #include <hgraph.h> Contains function prototypes void hstr(column, row, string, attrib, count); hstr ______ ___ ______ ______ _____ int column; /* 0 through 89 */ ______ int row; /* 0 through 42 */ ___ char *string; /* pointer to the string */ ______ char attrib; /* HGNORM or HGINVS */ HGNORM HGINVS ______ int count; /* number of chars in string */ _____ ______ Description ___________ Writes the string pointed to by string at the row and ______ ___ column given after each character has been XORed with ______ attrib. The graphics page written to is set according ______ to the current value of HGPAGE (see hgraph_init). HGPAGE There is no bounds checking done on column and row so ______ ___ numbers outside of range will give unknown results (probably not good). Hstr's character table only has Hstr ASCII characters 0 through 127, values outside this range will give garbage. The attrib is xor with the ______ character's bits on each scan line, values other than HGNORM (normal) and HGINVS (inverse) will just produce HGNORM HGINVS odd patterns. Count tells hstr how many of string's hstr _____ ______ characters to plot. MSC regular run-time LIB has a functions strlen() and gcvt(), strlen() will produce a correct count and gcvt() will convert numbers to a _____ string so they can be printed. Return Value ____________ There is no return value. See Also ________ hchar, hchar2, hwrite, hxchar, hxchar2, hxstr MSC's or QuickC's strlen() and gcvt() Note: _____ This is the fastest of hstr, hchar, and hchar2 for writing strings because it operates on byte boundaries. Only if you really need to write at a particular pixel location should hchar or hchar2 be used and of these two hchar2 is the better (only because its character table is internal, the same as hstr, so it is guaranteed to work on all machines). 17 HGRAPH.LIB V1.01 HGRAPH.LIB HTMODE HTMODE Summary _______ #include <hgraph.h> Contains function prototypes void htmode(void); htmode Description ___________ Sets text mode, clears graphic pages 0 and 1 then switches to text page. Return Value ____________ There is no return value. See Also ________ htmode_nc 18 HGRAPH.LIB V1.01 HGRAPH.LIB HTMODE_NC HTMODE_NC Summary _______ #include <hgraph.h> Contains function prototypes void htmode_nc(void); htmode_nc Description ___________ Sets text mode, does not clears graphic pages 0 and 1 ________ then switches to text page. Return Value ____________ There is no return value. See Also ________ htmode 19 HGRAPH.LIB V1.01 HGRAPH.LIB HWRITE HWRITE Summary _______ #include <hgraph.h> Contains function prototypes int hwrite(row, col, string); hwrite ___ ___ ______ int row; /* 0 through 42 */ ___ int col; /* 0 through 89 */ ___ char *string; /* pointer to the string */ ______ Description ___________ Write string starting at (row, col) using the attribute ______ ___ ___ value of HGATRB (see hgraph_init). The string is HGATRB written to the graphics page set according to the current value of HGPAGE (see hgraph_init). Hwrite HGPAGE Hwrite checks for bounds on both row and col, if the start of ___ ___ the string is not on the screen the string will not be written. If the string runs off the right edge it will just be truncated to avoid errors. MSC regular run- time LIB has a function gcvt() which will convert numbers to a string so they can be printed. Return Value ____________ Hwrite will return a 1 if it wrote any thing on the Hwrite screen (truncated or not) or a 0 if (row, col) was off ___ ___ the screen (nothing written). See Also ________ hchar, hchar2, hstr, hxchar, hxchar2, hxstr MSC's or QuickC's gcvt() 20 HGRAPH.LIB V1.01 HGRAPH.LIB HXCHAR HXCHAR Summary _______ #include <hgraph.h> Contains function prototypes void hxchar(x, y, string, attrib, count); hxchar _ _ ______ ______ _____ int x; /* 0 through 719 */ _ int y; /* 0 through 347 */ _ char *string; /* ASCII 0 through 127 */ ______ char attrib; /* HGNORM or HGINVS */ HGNORM HGINVS ______ int count; /* number of chars in string */ _____ ______ Description ___________ XORs string starting at the upper left most corner of ______ the string pointed to by string at the coordinates ______ given after each character has been XORed with attrib. ______ Hxchar writes to the graphics page set by the current Hxchar value of HGPAGE (see hgraph_init). There is no bounds HGPAGE checking done on x and y so numbers outside of range _ _ will give unknown results (probably not good). Hxchar Hxchar uses the IBM PC/XT/AT ROM character table. This table only has ASCII characters 0 through 127, values outside this range will give garbage. The attrib is xor with ______ the character's bits before it is xored to the screen, values other than HGNORM (normal) and HGINVS (inverse) HGNORM HGINVS for attrib will just produce odd patterns. Count tells ______ _____ hchar how many of string's characters to plot. MSC hchar ______ regular run-time LIB has a functions strlen() and gcvt(), strlen() will produce a correct count and _____ gcvt() will convert numbers to a string. Return Value ____________ There is no return value. See Also ________ hchar, hchar2, hstr, hwrite, hxchar2, hxstr MSC's or QuickC's strlen() and gcvt() 21 HGRAPH.LIB V1.01 HGRAPH.LIB HXCHAR2 HXCHAR2 Summary _______ #include <hgraph.h> Contains function prototypes void hxchar2(x, y, string, attrib, count); hxchar2 _ _ ______ ______ _____ int x; /* 0 through 719 */ _ int y; /* 0 through 347 */ _ char *string; /* ASCII 0 through 127 */ ______ char attrib; /* HGNORM or HGINVS */ HGNORM HGINVS ______ int count; /* number of chars in string */ _____ ______ Description ___________ XORs string starting at the upper left most corner of ______ the string pointed to by string at the coordinates ______ given after each character has been XORed with attrib. ______ Hxchar2 writes to the graphics page according to the Hxchar2 current value of HGPAGE (see hgraph_init). There is no HGPAGE bounds checking done on x and y so numbers outside of _ _ range will give unknown results (probably not good). Hxchar2's character table only has ASCII characters 0 Hxchar2 through 127, values outside this range will give garbage. The attrib is xor with the character's bits ______ before it is xored to the screen, values other than HGNORM (normal) and HGINVS (inverse) for attrib will HGNORM HGINVS ______ just produce odd patterns. Count tells hxchar2 how hxchar2 _____ many of string's characters to plot. MSC regular run- ______ time LIB has a functions strlen() and gcvt(), strlen() will produce a correct count and gcvt() will convert _____ numbers to a string. Return Value ____________ There is no return value. See Also ________ hchar, hchar2, hstr, hwrite, hxchar, hxstr MSC's or QuickC's strlen() and gcvt() 22 HGRAPH.LIB V1.01 HGRAPH.LIB HXLINE HXLINE Summary _______ #include <hgraph.h> Contains function prototypes void hxline(x0, y0, x1, y1); hxline __ __ __ __ int x0; /* 0 through 719 */ __ int y0; /* 0 through 347 */ __ int x1; /* 0 through 719 */ __ int y1; /* 0 through 347 */ __ Description ___________ Toggles the status of all the pixels along the given line. The graphics page is set according to the current value of HGPAGE (see hgraph_init). There is no HGPAGE bounds checking done on x0, x1, y0, or y1 so numbers __ __ __ __ outside of range will give unknown results (probably not good). Return Value ____________ There is no return value. See Also ________ hline 23 HGRAPH.LIB V1.01 HGRAPH.LIB HXSTR HXSTR Summary _______ #include <hgraph.h> Contains function prototypes void hxstr(column, row, string, attrib, count); hxstr ______ ___ ______ ______ _____ int column; /* 0 through 89 */ ______ int row; /* 0 through 42 */ ___ char *string; /* pointer to the string */ ______ char attrib; /* HGNORM or HGINVS */ HGNORM HGINVS ______ int count; /* number of chars in string */ _____ ______ Description ___________ XORs the string pointed to by string at the row and ______ ___ column given after each character has been XORed with ______ attrib. The graphics page written to is set according ______ to the current value of HGPAGE (see hgraph_init). HGPAGE There is no bounds checking done on column and row so ______ ___ numbers outside of range will give unknown results (probably not good). Hstr's character table only has Hstr ASCII characters 0 through 127, values outside this range will give garbage. The attrib is xor with the ______ character's bits before it is xored to the screen, values other than HGNORM (normal) and HGINVS (inverse) HGNORM HGINVS will just produce odd patterns. Count tells hstr how hstr _____ many of string's characters to plot. MSC regular run- ______ time LIB has a functions strlen() and gcvt(), strlen() will produce a correct count and gcvt() will convert _____ numbers to a string so they can be printed. Return Value ____________ There is no return value. See Also ________ hchar, hchar2, hstr, hwrite, hxchar, hxchar2 MSC's or QuickC's strlen() and gcvt() Note: _____ This is the fastest of hxstr, hxchar, and hxchar2 for writing strings because it operates on byte boundaries. Only if you really need to write at a particular pixel location should hxchar or hxchar2 be used and of these two hxchar2 is the better (only because its character table is internal, the same as hxstr, so it is guaranteed to work on all machines). 24 HGRAPH.LIB V1.01 HGRAPH.LIB Appendix A Appendix A (examples) 25 HGRAPH.LIB V1.01 HGRAPH.LIB /* CORNUCOPIA -- see article on "pseudo-hidden line removal" */ /* IBM-PC Exchange, May-June 1986 */ #include <math.h> #include <conio.h> #include <hgraph.h> main() { int d, a0, b0, a1, b1, a, b; double r, rada, radb; hgraph_init(); hgmode_nc(); hclearpg(); hshowpg(); hstr(40, 1, " CORNUCOPIA ", 0xff, 12); for (d = 1; d <= 100; ++d) { rada = (float)d; radb = 0.65 * rada; a0 = 20 + 4 * d; b0 = 20 + 2 * d + (int)(radb * 0.6 * sin(d/10.0)); hline(0, a0, b0, a1 = a0, b1 = b0 + (int)radb); for (r = 0.0; r < 6.3; r += 6.28/40.0) { a = a0 + (int)(rada * sin(r)); b = b0 + (int)(radb * cos(r)); hline(1, a1, b1, a, b); hline(0, a0, b0, a1 = a, b1 = b); } } /* This next section flips back and forth from * text to graphics three time to show the use of the * non-clearing hgmode_nc & htmode_nc the user must hit a * key to cause the flip */ hstr(10, 40, "Press any key to continue ... ", 0x00, 30); getch(); htmode_nc(); puts("Press any key to continue ... "); getch(); hgmode_nc(); hshowpg(); getch(); htmode_nc(); getch(); hgmode_nc(); hshowpg(); getch(); htmode(); /* this will clear the text screen */ } 26 HGRAPH.LIB V1.01 HGRAPH.LIB /* DEMO.C - a demo of hgraph.lib's string writing routines */ #include <string.h> #include <conio.h> #include <hgraph.h> char string[40] = "HGRAPH.LIB"; main() { int ct; char c; ct = strlen(string); hgraph_init(); hgmode_nc(); hclearpg(); hshowpg(); hstr(40, 1, string, HGINVS, ct); hstr(20, 10, "This is a demo of hstr, hchar, and hchar2", HGNORM, 41); hstr(10, 20, "This is a sample of hstr with normal attrib", HGNORM,43); hstr(10, 21, "This is a sample of hstr with inverse attrib", HGINVS,44); hchar(80, 200, "This is a sample of hchar with normal attrib", HGNORM,44); hchar(80, 209, "This is a sample of hchar with inverse attrib",HGINVS,45); hchar2(80, 240, "This is a sample of hchar2 with normal attrib",HGNORM,45); hchar2(80, 249, "This is a sample of hchar2 with inverse attrib",HGINVS,46); hstr(10, 40, "Press any key to continue ...", HGNORM, 29); getch(); htmode_nc(); } 27 HGRAPH.LIB V1.01 HGRAPH.LIB Appendix B Appendix B (programing ideas) 28 HGRAPH.LIB V1.01 HGRAPH.LIB There are three ways to do screen swapping with these libraries to make it appear that you have a a full screen type window package. I will start with the easiest and work up to what I would consider the best. There is one thing to keep in mind, the text screen uses the same memory as the first half of graphics page 0. This fact must be consider when using hgmode_nc() and htmode_nc() because if you have written stuff to the text screen and then go to graphics page 0 there will be garbage on the top half of the monitor. The same is true if you do graphics on page 0 and switch to text with out clearing there will be trash all over the text screen. 1) If you do all your graphics on page 1 (the default) you could use C's standard functions (i.e printf, puts, ...) to write to the text screen (you don't have to leave graphics mode to do this). This way you could have graphics displayed and a help screen written to the text screen so if the user hit F1 you could call htmode_nc() and the help screen would appear, and then another key would call hgmode_nc() and the graphics would reappear. The only problem with this is a half to three quarters of a second delay built into both htmode_nc() and hgmode_nc() this will cause approximately a one second delay in switching form one screen to another. 2) There are two undocumented routines in hgraph.lib. void h_scrn_in( unsigned char *) void h_scrn_out( unsigned char *) where unsigned char * is a pointer to a buffer of at least 32768 bytes. The first, h_scrn_in reads the screen defined by HGPAGE and stores it into the buffer it was passed HGPAGE as an argument. The second, h_scrn_out copies the first 32767 bytes from the buffer it was passed as an argument to the screen defined by HGPAGE. So HGPAGE in the middle of doing graphics the user hits a key for help, the program would use h_scrn_in to save a copy of the current screen. Then it would call hclearpg followed by hwrite to display help messages. When the user wanted to switch back just call h_scrn_out and rewrite the image back. 29 HGRAPH.LIB V1.01 HGRAPH.LIB 3) What I feel is the best is to use one graphics page for graphics and one graphics page for help. All that would have to be done is to reset HGPAGE HGPAGE and then call hshowpg to swap between the two. The code in the library to figure out which page and to set it is only ten lines in assembly. 30