Originally Posted by
rahul_shilps
I am facing problem of
BGI Error: Graphics not initialized (use 'initgraph')
In fact i have provided correct invocation of initgraph method
initgraph(....,"C:\\Turboc3\\bgi");
i found that there is no file like bgi in Turboc3..
please help me how can i initialize graphics.
Help me.
In Turbo C/C++, the graphics driver files are in the C:\TC\BGI directory, by default.
This is how you use it, and an example program (which just draws a white line on a black graphics screen).
initgraph Initializes the graphics system.
Syntax:
void far initgraph(int far *graphdriver, int far *graphmode,
char far *pathtodriver);
Prototype in:
graphics.h
Remarks:
initgraph initializes the graphics system by loading a graphics driver from
disk (or validating a registered driver), and putting the system into
graphics mode.
To start the graphics system, first call the initgraph function. initgraph
loads the graphics driver and puts the system into graphics mode.
You can tell initgraph to use a particular graphics driver and mode, or to
autodetect the attached video adapter at run time and pick the corresponding
driver.
If you tell initgraph to autodetect, it calls detectgraph to select a
graphics driver and mode.
initgraph also resets all graphics settings to their defaults (current
position, palette, color, viewport, and so on) and resets graphresult to 0.
Normally, initgraph loads a graphics driver by allocating memory for the
driver (through _graphgetmem), then loading the appropriate .BGI file from
disk.
As an alternative to this dynamic loading scheme, you can link a graphics
driver file (or several of them) directly into your executable program file.
See UTIL.DOC (included with your distribution disks) for more information on
BGIOBJ.
þ pathtodriver specifies the directory path
where initgraph looks for graphics
drivers.
initgraph first looks in the path
specified in pathtodriver, then (if
they're not there) in the current
directory. Accordingly, if pathtodriver
is null, the driver files (*.BGI) must be
in the current directory.
This is also the path settextstyle
searches for the stroked character font
files (*.CHR).
þ *graphdriver is an integer that specifies
the graphics driver to be used. You can
give it a value using a constant of the
graphics_drivers enumeration type,
defined in graphics.h and listed in the
table below.
graphics_drivers ³
constant ³ Numeric value
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DETECT ³ 0 (requests autodetection)
CGA ³ 1
MCGA ³ 2
EGA ³ 3
EGA64 ³ 4
EGAMONO ³ 5
IBM8514 ³ 6
HERCMONO ³ 7
ATT400 ³ 8
VGA ³ 9
PC3270 ³ 10
þ *graphmode is an integer that specifies
the initial graphics mode (unless
*graphdriver equals DETECT. In this
case, *graphmode is set by initgraph to
the highest resolution available for the
detected driver).
You can give *graphmode a value using a
constant of the graphics_modes
enumeration type, defined in graphics.h
and listed in the table above.
graphdriver and graphmode must be set to valid values from or you'll get
unpredictable results.
The exception is graphdriver = DETECT.
In the following table, the palette listings C0, C1, C2, and C3 refer to the
four predefined four-color palettes available on CGA (and compatible)
systems.
You can select the background color (entry #0) in each of these palettes,
but the other colors are fixed.
These palettes are described in greater detail in Chapter video, "videott,"
in book3 (in the section titled "Color control," toward the end of the
chapter) and summarized in Table palette.
Palette ³ Color assigned to pixel value
number ³ 1 2 3
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0 ³ LIGHTGREEN ³ LIGHTRED ³ YELLOW
1 ³ LIGHTCYAN ³ LIGHTMAGENTA ³ WHITE
2 ³ GREEN ³ RED ³ BROWN
3 ³ CYAN ³ MAGENTA ³ LIGHTGRAY
After a call to initgraph, *graphdriver is set to the current graphics
driver, and *graphmode is set to the current graphics mode.
Graphics³ ³ ³ Column ³ ³
driver ³ graphics_modes ³ Value ³ x row ³ Palette ³ Pages
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CGA ³ CGAC0 ³ 0 ³ 320 x 200³ C0 ³ 1
³ CGAC1 ³ 1 ³ 320 x 200³ C1 ³ 1
³ CGAC2 ³ 2 ³ 320 x 200³ C2 ³ 1
³ CGAC3 ³ 3 ³ 320 x 200³ C3 ³ 1
³ CGAHI ³ 4 ³ 640 x 200³ 2 color³ 1
MCGA ³ MCGAC0 ³ 0 ³ 320 x 200³ C0 ³ 1
³ MCGAC1 ³ 1 ³ 320 x 200³ C1 ³ 1
³ MCGAC2 ³ 2 ³ 320 x 200³ C2 ³ 1
³ MCGAC3 ³ 3 ³ 320 x 200³ C3 ³ 1
³ MCGAMED ³ 4 ³ 640 x 200³ 2 color³ 1
³ MCGAHI ³ 5 ³ 640 x 480³ 2 color³ 1
EGA ³ EGALO ³ 0 ³ 640 x 200³ 16 color³ 4
³ EGAHI ³ 1 ³ 640 x 350³ 16 color³ 2
EGA64 ³ EGA64LO ³ 0 ³ 640 x 200³ 16 color³ 1
³ EGA64HI ³ 1 ³ 640 x 350³ 4 color³ 1
EGA-MONO³ EGAMONOHI ³ 3 ³ 640 x 350³ 2 color³ 1*
³ EGAMONOHI ³ 3 ³ 640 x 350³ 2 color³ 2**
HERC ³ HERCMONOHI ³ 0 ³ 720 x 348³ 2 color³ 2
ATT400 ³ ATT400C0 ³ 0 ³ 320 x 200³ C0 ³ 1
³ ATT400C1 ³ 1 ³ 320 x 200³ C1 ³ 1
³ ATT400C2 ³ 2 ³ 320 x 200³ C2 ³ 1
³ ATT400C3 ³ 3 ³ 320 x 200³ C3 ³ 1
³ ATT400MED ³ 4 ³ 640 x 200³ 2 color³ 1
³ ATT400HI ³ 5 ³ 640 x 400³ 2 color³ 1
VGA ³ VGALO ³ 0 ³ 640 x 200³ 16 color³ 2
³ VGAMED ³ 1 ³ 640 x 350³ 16 color³ 2
³ VGAHI ³ 2 ³ 640 x 480³ 16 color³ 1
PC3270 ³ PC3270HI ³ 0 ³ 720 x 350³ 2 color³ 1
IBM8514 ³ IBM8514HI ³ 1 ³ 1024 x 760³ 256 color³
³ IBM8514LO ³ 0 ³ 640 x 480³ 256 color³
* 64K on EGAMONO card
** 256K on EGAMONO card
Return Value:
initgraph always sets the internal error code.
On success, it sets the code to 0. If an error occurred, *graphdriver is set
to -2, -3, -4, or -5, and graphresult returns the same value as listed in
the following table:
grNotDetected ³ -2 ³ Cannot detect a graphics card
grFileNotFound ³ -3 ³ Cannot find driver file
grInvalidDriver ³ -4 ³ Invalid driver
grNoLoadMem ³ -5 ³ Insufficient memory to load driver
Portability:
This function is unique to Turbo C++.
It works only with IBM PCs and compatibles equipped with supported graphics
display adapters.
See Also:
closegraph graphresult
detectgraph installuserdriver
getdefaultpalette registerbgidriver
getdrivername registerbgifont
getgraphmode restorecrtmode
getmoderange setgraphbufsize
graphdefaults setgraphmode
_graphgetmem
Example:
Code:
#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
/* initialize graphics mode */
initgraph(&gdriver, &gmode, "");
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* return with error code */
}
/* draw a line */
line(0, 0, getmaxx(), getmaxy());
/* clean up */
getch();
closegraph();
return 0;
}
This runs on two of my graphics cards, in Windows XP. The aspect ratio may distort things, depending on your monitor' and graphics cards settings.
