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,
byte fgcol,
byte bgcol,
int fill,
int dir);
void
VGLBitmapString
(
VGLBitmap
*Object,
int
x,
int y,
char *str,
byte fgcol,
byte 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 byte
value.
VGLSetXY
() sets the color of the pixel
located at
x,
y, coordinates of the
object argument to
color byte 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.
Søren Schmidt
<
sos@FreeBSD.org>