VGLBitmapAllocateBits
,
VGLBitmapCopy
,
VGLBitmapCreate
,
VGLBitmapDestroy
,
VGLBitmapPutChar
,
VGLBitmapString
,
VGLBlankDisplay
, VGLBox
,
VGLCheckSwitch
, VGLClear
,
VGLEllipse
, VGLEnd
,
VGLFilledBox
,
VGLFilledEllipse
, VGLGetXY
,
VGLInit
, VGLLine
,
VGLKeyboardInit
,
VGLKeyboardEnd
,
VGLKeyboardGetCh
,
VGLMouseInit
, VGLMouseMode
,
VGLMouseSetImage
,
VGLMouseSetStdImage
,
VGLMouseStatus
, VGLPanScreen
,
VGLSetBorder
, VGLSetPalette
,
VGLSetPaletteIndex
,
VGLSetVScreenSize
, VGLSetXY
,
VGLTextSetFontFile
—
Video Graphics Library functions
Video Graphics Library (libvgl, -lvgl)
#include <sys/fbio.h>
#include <sys/consio.h>
#include <sys/kbio.h>
#include <vgl.h>
int
VGLInit
(int
mode);
void
VGLEnd
(void);
void
VGLCheckSwitch
(void);
int
VGLTextSetFontFile
(char
*filename);
int
VGLKeyboardInit
(int
code);
void
VGLKeyboardEnd
(void);
int
VGLKeyboardGetCh
(void);
int
VGLMouseInit
(int
mode);
void
VGLMouseMode
(int
mode);
int
VGLMouseStatus
(int
*x, int *y,
char *buttons);
void
VGLMouseSetImage
(VGLBitmap
*AndMask, VGLBitmap
*OrMask);
void
VGLMouseSetStdImage
(void);
u_long
VGLGetXY
(VGLBitmap
*object, int x,
int y);
void
VGLSetXY
(VGLBitmap
*object, int x,
int y,
u_long color);
void
VGLLine
(VGLBitmap
*object, int x1,
int y1,
int x2,
int y2,
u_long color);
void
VGLBox
(VGLBitmap
*object, int x1,
int y1,
int x2,
int y2,
u_long color);
void
VGLFilledBox
(VGLBitmap
*object, int x1,
int y1,
int x2,
int y2,
u_long color);
void
VGLEllipse
(VGLBitmap
*object, int xc,
int yc,
int a,
int b,
u_long color);
void
VGLFilledEllipse
(VGLBitmap
*object, int xc,
int yc,
int a,
int b,
u_long color);
VGLBitmap *
VGLBitmapCreate
(int
type, int xsize,
int ysize,
byte *bits);
void
VGLBitmapDestroy
(VGLBitmap
*object);
int
VGLBitmapAllocateBits
(VGLBitmap
*object);
int
VGLBitmapCopy
(VGLBitmap
*src, int srcx,
int srcy,
VGLBitmap *dst,
int dstx,
int dsty,
int width,
int hight);
void
VGLBitmapPutChar
(VGLBitmap
*Object, int x,
int y,
byte ch,
u_long fgcol,
u_long bgcol,
int fill,
int dir);
void
VGLBitmapString
(VGLBitmap
*Object, int x,
int y,
char *str,
u_long fgcol,
u_long bgcol,
int fill,
int dir);
void
VGLClear
(VGLBitmap
*object, u_long
color);
void
VGLSetPalette
(byte
*red, byte *green,
byte *blue);
void
VGLSetPaletteIndex
(byte
color, byte red,
byte green,
byte blue);
void
VGLSetBorder
(byte
color);
int
VGLSetVScreenSize
(VGLBitmap
*object, int
vxsize, int
vysize);
int
VGLPanScreen
(VGLBitmap
*object, int x,
int y);
void
VGLBlankDisplay
(int
blank);
Libvgl
is a library that enables the programmer access
to the graphics modes supported by the console driver (syscons). The library
takes care of programming the actual video hardware, and provides a number of
simple functions to do various graphic operations. There is also support for a
mouse via the standard mouse system in FreeBSD, see
mouse(4),
including the ability to transparently have a mouse pointer superimposed on
the graphic image currently being worked on. The library takes care of screen
switching by storing the current image in memory before switching to another
virtual console, and restoring when the user switches back. This allows
several graphic applications at once, but on different virtual consoles.
Below is a short description of the various functions:
VGLInit
() initialize the library and set
up the graphic mode mode.
VGLEnd
() terminate graphic mode, and
restore the screenmode that was active before
VGLInit
() was called.
VGLCheckSwitch
() if the program goes into
longer periods of processing without doing any graphics output, calling this
function occasionally will allow the system to switch screens.
VGLTextSetFontFile
() instruct the
char/string functions to use the font in file
filename instead of the builtin font.
VGLKeyboardInit
() set up the keyboard in
the “raw” I/O mode and specify the key code to be used.
code must be VGL_XLATEKEYS
,
VGL_CODEKEYS
, or
VGL_RAWKEYS
. When
VGL_XLATEKEYS
is specified, the keyboard translates
the raw keyboard scan code into a character code. If
VGL_RAWKEYS
is used, the raw keyboard scan code is
read as is. VGL_CODEKEYS
is the intermediate key
code; each key is assigned a unique code whereas more than one raw scan code
may be generated when a key is pressed.
VGLKeyboardEnd
() when you have finished
using the keyboard, call this function.
VGLKeyboardGetCh
() read one byte from the
keyboard. As the keyboard I/O is in the “raw” input mode, the
function will not block even if there is no input data, and returns 0.
VGLMouseInit
() initialize the mouse. The
optional on-screen mouse pointer is shown if the argument is
VGL_MOUSESHOW
.
VGLMouseMode
() either shows the mouse
pointer if the argument is VGL_MOUSESHOW
, or hides
the mouse pointer if the argument is
VGL_MOUSEHIDE
.
VGLMouseStatus
() returns the current mouse
pointer coordinates and button state in x,
y, buttons. The return value reflects if the mouse
pointer is currently shown on screen or not.
VGLMouseSetImage
() with this function it
is possible to change the image of the mouse pointer on screen.
VGLMouseSetStdImage
() this function
restores the mouse pointer to the standard arrow.
VGLGetXY
() retrieves the color of the
pixel located at x, y,
coordinates of the object argument, and returns it as
a u_long value.
VGLSetXY
() sets the color of the pixel
located at x, y, coordinates of
the object argument to color
u_long value.
VGLLine
() draw a line from
x1, y1 to
x2, y2 in color
color.
VGLBox
() draw a box with upper left hand
corner at x1, y1 and lower right
hand corner at x2, y2 in color
color.
VGLFilledBox
() draw a filled (solid) box
with upper left hand corner at x1,
y1 and lower right hand corner at
x2, y2 in color
color.
VGLEllipse
() draw an ellipse centered at
xc, yc make it
a pixels wide, and b pixels high
in color color.
VGLFilledEllipse
() draw a filled (solid)
ellipse centered at xc, yc make
it a pixels wide, and b pixels
high in color color.
VGLBitmapCreate
() create a bitmap object
and initialize it with the specified values and bit data.
type must be MEMBUF
for the
in-memory bitmap. bits may be NULL so that bitmap data
may be associated later.
There also is a macro,
VGLBITMAP_INITIALIZER
(type,
xsize, ysize,
bits) to initialize a statically declared bitmap
object.
VGLBitmapDestroy
() free the bitmap data
and the bitmap object.
VGLBitmapAllocateBits
() allocate a bit
data buffer for the specified object.
VGLBitmapCopy
() copy a rectangle of pixels
from bitmap src upper left hand corner at
srcx, srcy to bitmap
dst at dstx,
dsty of the size width,
height.
VGLBitmapPutChar
() write the character
ch at position x,
y in foreground color fgcol. If
fill is != 0, use the color
bgcol as background otherwise the background is
transparent. The character is drawn in the direction specified by the
argument dir.
VGLBitmapString
() write the string
str at position x,
y in foreground color fgcol. If
fill is != 0, use the color
bgcol as background otherwise the background is
transparent. The string is drawn in the direction specified by the argument
dir.
VGLClear
() clears the entire bitmap to
color color.
VGLSetPalette
() this function sets the
palette used, the arguments red,
green, blue should point to byte
arrays of 256 positions each.
VGLSetPaletteIndex
() set the palette index
color to the specified RGB value.
VGLSetBorder
() set the border color to
color color.
VGLSetVScreenSize
() change the virtual
screen size of the display. Note that this function must be called when our
vty is in the foreground. And object must be
VGLDisplay. Passing an in-memory bitmap to this
function results in error.
The desired virtual screen width may not be achievable because of
the video card hardware. In such case the video driver (and underlying video
BIOS) may choose the next largest values. Always examine
object->VXsize and VYsize
after calling this function, in order to see how the virtual screen is
actually set up.
In order to set up the largest possible virtual screen, you may
call this function with arbitrary large values.
VGLSetVScreenSize(10000,
10000);
VGLPanScreen
() change the origin of the
displayed screen in the virtual screen. Note that this function must be
called when our vty is in the foreground. object must
be VGLDisplay. Passing an in-memory bitmap to this
function results in error.
VGLBlankDisplay
() blank the display if the
argument blank ≠ 0. This can be done to shut
off the screen during display updates that the user should first see when it
is done.
It is important to call VGLEnd
() before terminating the
program. Care must be taken if you install signal handlers and try to call
VGLEnd
() and
exit(3) to
end the program. If a signal is caught while the program is inside
libvgl
functions, VGLEnd
() may
not be able to properly restore the graphics hardware.
The recommended way to handle signals and program termination is
to have a flag to indicate signal's delivery. Your signal handlers set this
flag but do not terminate the program immediately. The main part of the
program checks the flag to see if it is supposed to terminate, and calls
VGLEnd
() and
exit(3)
if the flag is set.
Note that VGLInit
() installs its internal
signal handlers for SIGINT
,
SIGTERM
, SIGSEGV
, and
SIGBUS
, and terminates the program at appropriate
time, after one of these signals is caught. If you want to have your own
signal handlers for these signals, install handlers after
VGLInit
().
SIGUSR1
and
SIGUSR2
are internally used by
libvgl
to control screen switching and the mouse
pointer, and are not available to libvgl
client
programs.
The vgl
library appeared in FreeBSD
3.0.