Category : C++ Source Code
Archive   : C_ALL.ZIP
Filename : TI707.ASC

PRODUCT : Borland C++ NUMBER : 707
VERSION : 2.0
OS : DOS
DATE : September 3, 1992 PAGE : 1/3

TITLE : Linking Third Party BGI Drivers




/*************************************************************
This document explains how to link third party graphics drivers
into your program. This example is specific to the vga256.bgi
driver which is available on the Borland BBS (408) 439-9096. The
procedure is the same to link in one of the drivers that was
shipped with your product except that you don't need to make the
call to installuserdriver() function which means that you also
don't need the alwayszero() function.

1. Convert vga256.bgi to an object file with this command:

BGIOBJ vga256.bgi vga256.obj _vga256_driver

2. Create a project file for the program that links in the
driver. The project should contain two items:

A. test.c
B. vga256.obj

3. Here's what test.c would look like:

************************************************************/

#include
#include
#include
#include

/* function prototypes */
int huge alwayszero(void);
void checkerrors(void);
void _Cdecl vga256_driver(void);


int main(void)
{
int gdriver, gmode;

/* install the user defined driver into the system */
gdriver = installuserdriver("vga256", alwayszero);

/* check for any installation errors */
checkerrors();













PRODUCT : Borland C++ NUMBER : 707
VERSION : 2.0
OS : DOS
DATE : September 3, 1992 PAGE : 2/3

TITLE : Linking Third Party BGI Drivers




/* register the driver with the graphics system */
registerbgidriver(vga256_driver);

/* check for any installation errors */
checkerrors();

/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, "");

/* check for any initialization errors */
checkerrors();

/* draw a line */
setcolor(WHITE);
line(0, 0, getmaxx(), getmaxy());

/* clean up */
getch();
closegraph();
return 0;
}

int huge alwayszero(void)
{
return 0;
}

/* check for and report any graphics errors */
void checkerrors(void)
{
int errorcode;

/* read result of last graphics operation */
errorcode = graphresult();
if (errorcode != grOk)
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1);
}
}














PRODUCT : Borland C++ NUMBER : 707
VERSION : 2.0
OS : DOS
DATE : September 3, 1992 PAGE : 3/3

TITLE : Linking Third Party BGI Drivers




DISCLAIMER: You have the right to use this technical information
subject to the terms of the No-Nonsense License Statement that
you received with the Borland product to which this information
pertains.