.TH svgalib 7 "16 December 1999" "Svgalib 1.4.1" "Svgalib User Manual"
.SH NAME
svgalib \- a low level graphics library for linux
.SH TABLE OF CONTENTS

.BR 0. " Introduction"
.br
.BR 1. " Installation"
.br
.BR 2. " How to use svgalib"
.br
.BR 3. " Description of svgalib functions"
.br
.BR 4. " Overview of supported SVGA chipsets and modes"
.br
.BR 5. " Detailed comments on certain device drivers"
.br
.BR 6. " Goals"
.br
.BR 7. " References (location of latest version, apps etc.)"
.br
.BR 8. " Known bugs"

.SH 0. INTRODUCTION

This is a low level graphics library for Linux, originally based on VGAlib 1.2 by
Tommy Frandsen. VGAlib supported a number of standard VGA graphics modes, as
well as Tseng ET4000 high resolution 256-color modes. As of now, support for many
more chipsets has been added. See section
.B 4 Overview of supported SVGA chipsets and modes

It supports transparent virtual console switching, that is, you can switch
consoles to and from text and graphics mode consoles using alt-[function
key]. Also, svgalib corrects most of VGAlib's textmode corruption behaviour
by catching
.BR SIGSEGV ", " SIGFPE ", " SIGILL ,
and other fatal signals and ensuring that a program is running
in the currently visible virtual console before setting a graphics mode.

Note right here that
.BR SIGUSR1 " and " SIGUSR2
are used to manage console switching internally in
.BR svgalib .
You can not use them in your programs. If your program needs to use one of
those signals, svgalib can be compiled to use other signals, by editing
libvga.h

This version includes code to hunt for a free virtual console on its own in
case you are not starting the program from one (but instead over a network or
modem login, from within
.BR screen (1)
or an
.BR xterm (1)).
Provided there is a free
console, this succeeds if you are root or if the svgalib calling user own
the current console. This is to avoid people not using the console being able
to fiddle with it.
On graceful exit the program returns to the console from which it was started.
Otherwise it remains in text mode at the VC which svgalib allocated to allow
you to see any error messages. In any case, any I/O the svgalib makes in
text mode (after calling
.BR vga_init (3))
will also take place at this new console.

Alas, some games misuse their suid root privilege and run as full root
process. svgalib cannot detect this and allows Joe Blow User to open a new
VC on the console. If this annoys you,
.B ROOT_VC_SHORTCUT
in
.I Makefile.cfg
allows
you to disable allocating a new VC for root (except when he owns the current
console) when you compile svgalib. This is the default.

When the library is used by a program at run-time, first the chipset is
detected and the appropriate driver is used. This means that a graphics
program will work on any card that is supported by svgalib, if the mode it
uses is supported by the chipset driver for that card. The library is
upwardly compatible with VGAlib.

The set of drawing functions provided by svgalib itself is limited (unchanged
from VGAlib) and unoptimized; you can however use
.BR vga_setpage (3)
and
.BR vga_getgraphmem (3)
(which points to the 64K VGA framebuffer) in a program or graphics library.
A fast external framebuffer graphics library for linear and banked 1, 2, 3
and 4 bytes per pixel modes is included (it also indirectly supports planar
VGA modes). It is documented in
.BR vgagl (7).

One obvious application of the library is a picture viewer. Several are
available, along with animation viewers. See the
.B 7. References
at the end of this document.

I have added a simple VGA textmode font restoration utility
.RB ( restorefont (1)) 
which may help if you suffer from XFree86 textmode font corruption. It can
also be used to change the textmode font. It comes with some other textmode utilities:
.BR restoretextmode (1)
(which saves/restores textmode registers),
.BR restorepalette (1),
and the script
.BR textmode (1).
If you run the
.BR savetextmode (1)
script to save textmode information to
.IR /tmp ,
you'll be able to restore textmode by running the
.BR textmode (1)
script.

.SH 1. INSTALLATION
Installation is easy in general but there are many options and things
you should keep in mind. This document however assumes that
.B svgalib
is already installed.

If you need information on installation see
.I 0-INSTALL
which comes with the svgalib distribution.

However, even after installation of the library you might need to configure
svgalib using the file
.IR /etc/vga/libvga.config .
Checkout section
.B 4 Overview of supported SVGA chipsets and modes
and
.BR libvga.config (5)
for information.

.SH 2. HOW TO USE SVGALIB

For basic svgalib usage (no mouse, no raw keyboard) add
.B #include <vga.h>
at the beginning your program.
Use
.BR vga_init (3)
as your first
.B svgalib
call. This will give up root privileges right
after initialization, making setuid-root binaries relatively safe.

The function
.BR vga_getdefaultmode (3)
checks the environment variable
.B SVGALIB_DEFAULT_MODE
for a default mode, and returns the corresponding mode number. The
environment string can either be a mode number or a mode name as in
.RB ( "G640x480x2" ", " "G640x480x16" ", " "G640x480x256 ", "
.BR G640x480x32K ", " G640x480x64K ", " G640x480x16M ).
As an example, to set the default
graphics mode to 640x480, 256 colors, use:

.B export SVGALIB_DEFAULT_MODE=G640x480x256

on the
.BR bash(1)
command line. If a program needs just a linear VGA/SVGA resolution (as required by
.BR vgagl (7)),
only modes where
.B bytesperpixel
in the
.B vga_modeinfo
structure returned by
.BR vga_getmodeinfo (3)
is greater or equal to 1 should be accepted (this is 0 for tweaked
planar 256-color VGA modes).

Use
.BI vga_setmode( graphicsmode )
to set a graphics mode. Use
.B vga_setmode(TEXT)
to restore textmode before program exit.

Programs that use svgalib must
.BR #include<vga.h> ;
if they also use the external graphics library
.BR vgagl (7),
you must also
.BR #include<vgagl.h> .
Linking must be done
with
.B -lvga
(and
.BR -lvgagl " before " -lvga ,
if
.BR vgagl (7)
is used). You can save binary space by removing the unused chipset drivers in
.I Makefile.cfg
if you only use specific chipsets. However this reduces the flexibility of svgalib
and has a significant effect only when you use the static libraries. You should better
use the shared libraries and these will load only the really used parts anyway.

Functions in the
.BR vgagl (7)
library have the prefix
.BR gl_ .
Please see
.BR vgagl (7)
for details.

There are demos with sources available which will also help to get you started, in
recommended order of interest:
.BR vgatest (6),
.BR keytest (6),
.BR mousetest (6),
.BR eventtest (6),
.BR forktest (6),
.BR bg_test (6),
.BR scrolltest (6),
.BR speedtest (6),
.BR fun (6),
.BR spin (6),
.BR testlinear (6),
.BR lineart (6),
.BR testgl (6),
.BR accel (6),
.BR testaccel (6),
.BR plane "(6), and "
.BR wrapdemo (6).

Debugging your programs will turn out to be rather difficult, because the svgalib
application can not restore textmode when it returns to the debugger.

Happy are the users with a serial terminal, X-station, or another way to log into the machine
from network. These can use

.BI "textmode </dev/tty" N

on the console where the program runs and continue.

However, the
.BR vga_flip (3)
function allows you to switch to textmode by entering a call to it blindly into your debugger
when your program stops in graphics mode.
.BR vga_flip (3)
is not very robust though. You shall not call it when svgalib is not yet initialized or
in textmode.

Before continuing your program, you must then call
.BR vga_flip (3)
again to return to graphics mode. If the program will not make any screen accesses or svgalib
calls before it returns to the debugger, you can omit that, of course.

This will only work if your program and the debugger run in the same virtual linux console.

.SH 3. DESCRIPTION OF SVGALIB FUNCTIONS
Each function has its own section 3 manual page. For a list of
.BR vgagl " functions see " vgagl (7).

.PD 0
.SS Initialization
.TP
.BR vga_init (3)
- initialize svgalib library.
.TP
.BR vga_disabledriverreport (3)
- makes svgalib not emit any startup messages.
.TP
.BR vga_claimvideomemory (3)
- declare the amount of video memory used.
.TP
.BR vga_safety_fork (3)
- start a parallel process to restore the console at a crash.
.TP
.BR vga_setchipset (3)
- force chipset.
.TP
.BR vga_setchipsetandfeatures (3)
- force chipset and optional parameters.

.SS Inquire hardware configuration
.TP
.BR vga_getmousetype (3)
- returns the mouse type configured.
.TP
.BR vga_getcurrentchipset (3)
- returns the current SVGA chipset.
.TP
.BR vga_getmonitortype (3)
- returns the monitor type configured.

.SS Setting video modes
.TP
.BR vga_setmode (3)
- sets a video mode.
.TP
.BR vga_setdisplaystart (3)
- set the display start address.
.TP
.BR vga_setlogicalwidth (3)
- set the logical scanline width.
.TP
.BR vga_setlinearaddressing (3)
- switch to linear addressing mode.
.TP
.BR vga_setmodeX (3)
- try to set Mode X-like memory organization .
.TP
.BR vga_ext_set (3)
- set and query several extended features.
.TP
.BR vga_screenoff "(3), " vga_screenon (3)
- turn generation of the video signal on or off.

.SS Get video mode information
.TP
.BR vga_getxdim "(3), " vga_getydim "(3), " vga_getcolors (3)
- return the current screen resolution.
.TP
.BR vga_white (3)
- return the color white in the current screen resolution.
.TP
.BR vga_getcurrentmode (3)
- returns the current video mode.
.TP
.BR vga_hasmode (3)
- returns if a video mode is supported.
.TP
.BR vga_getmodeinfo (3)
- returns pointer to mode information structure for a mode.
.TP
.BR vga_getdefaultmode (3)
- returns the default graphics mode number.
.TP
.BR vga_lastmodenumber (3)
- returns the last video mode number.
.TP
.BR vga_getmodename (3)
- return a name for the given video mode.
.TP
.BR vga_getmodenumber (3)
- return a number for the given video mode.

.SS Drawing primitives
.TP
.BR vga_clear (3)
- clear the screen.
.TP
.BR vga_setcolor (3)
- set the current color.
.TP
.BR vga_setrgbcolor (3)
- set the current color.
.TP
.BR vga_setegacolor (3)
- set the current color.
.TP
.BR vga_drawpixel (3)
- draw a pixel on the screen.
.TP
.BR vga_drawscanline (3)
- draw a horizontal line of pixels.
.TP
.BR vga_drawscansegment (3)
- draw a horizontal line of pixels.
.TP
.BR vga_drawline (3)
- draw a line on the screen.
.TP
.BR vga_getpixel (3)
- get a pixels value from the screen.
.TP
.BR vga_getscansegment (3)
- get a list of consecutive pixel values.
.TP
.BR vga_waitretrace (3)
- wait for vertical retrace.

.SS Basic (non raw) keyboard I/O
.TP
.BR vga_getch (3)
- wait for a key.
.TP
.BR vga_getkey (3)
- read a character from the keyboard without waiting.
.TP
.BR vga_waitevent (3)
- wait for various I/O events.

.SS Direct VGA memory access
.TP
.BR vga_setpage (3)
- set the 64K SVGA page number.
.TP
.BR vga_setreadpage (3)
- set the 64K SVGA page number.
.TP
.BR vga_setwritepage (3)
- set the 64K SVGA page number.
.TP
.BR vga_getgraphmem (3)
- returns the address of the VGA memory.
.TP
.BR vga_copytoplanar256 (3)
- copy linear pixmap into Mode X video memory.
.TP
.BR vga_copytoplanar16 (3)
- copy linear pixmap into VGA 16 color mode video memory.
.TP
.BR vga_copytoplane (3)
- copy linear pixmap to some planes of VGA 16 color mode video memory.

.SS Manage color lookup tables
.TP
.BR vga_setpalette (3)
- set a color in the color lookup table.
.TP
.BR vga_getpalette (3)
- get a color in the color lookup table.
.TP
.BR vga_setpalvec (3)
- sets colors in the color lookup table.
.TP
.BR vga_getpalvec (3)
- gets colors from the color lookup table.

.SS Mouse handling
.TP
.BR vga_setmousesupport (3)
- enable mouse support.
.TP
.BR mouse_init "(3), " mouse_init_return_fd (3)
- specifically initialize a mouse.
.TP
.BR mouse_close (3)
- explicitly close a mouse.
.TP
.BR mouse_update (3)
- updates the mouse state.
.TP
.BR mouse_waitforupdate (3)
- wait for an mouse update.
.TP
.BR mouse_setscale (3)
- sets a mouse scale factor.
.TP
.BR mouse_setwrap (3)
- set what happens at the mouse boundaries.
.TP
.BR mouse_setxrange "(3), " mouse_setyrange (3)
- define the boundaries for the mouse cursor.
.TP
.BR mouse_getx "(3), " mouse_gety "(3), " mouse_getbutton (3)
- query the mouse state.
.TP
.BR mouse_setposition (3)
- set the current mouse position.
.TP
.BR mouse_getposition_6d "(3), " mouse_setposition_6d "(3), " mouse_setrange_6d (3)
- provide an interface to 3d mice.
.TP
.BR mouse_seteventhandler "(3), " mouse_setdefaulteventhandler (3)
- set a mouse event handler.

.SS Raw keyboard handling
.TP
.BR keyboard_init "(3), " keyboard_init_return_fd (3)
- initialize the keyboard to raw mode.
.TP
.BR keyboard_close (3)
- return the keyboard to normal operation from raw mode.
.TP
.BR keyboard_update "(3), " keyboard_waitforupdate (3)
- process raw keyboard events.
.TP
.BR keyboard_translatekeys (3)
- modify scancode mappings in raw keyboard mode.
.TP
.BR keyboard_keypressed (3)
- check if a key is pressed when in raw keyboard mode.
.TP
.BR keyboard_getstate (3)
- get a pointer to a buffer holding the state of all keys in raw keyboard mode.
.TP
.BR keyboard_clearstate (3)
- reset the state of all keys when in raw keyboard mode.
.TP
.BR keyboard_seteventhandler "(3), " keyboard_setdefaulteventhandler (3)
- define an event handler for keyboard events in raw mode.

.SS Joystick handling
.TP
.BR joystick_init (3)
- initialize and calibrate joysticks.
.TP
.BR joystick_close (3)
- close a joystick device.
.TP
.BR joystick_update (3)
- query and process joystick state changes.
.TP
.BR joystick_sethandler "(3), " joystick_setdefaulthandler (3)
- define own joystick even handler.
.TP
.BR joystick_getnumaxes "(3), " joystick_getnumbuttons (3)
- query the capabilities of a joystick.
.TP
.BR joystick_getaxis "(3), " joystick_getbutton (3)
- query the state of a joystick.
.TP
.BR joystick_button1|2|3|4 "(3), " joystick_getb1|2|3|4 "(3), " joystick_x|y|z "(3), " joystick_getx|y|z (3)
- convenience macros to query the joystick position.

.SS Accelerator interface (new style)
.TP
.BR vga_accel (3)
- calls the graphics accelerator.

.SS Accelerator interface (old style)
.TP
.BR vga_bitblt (3)
- copy pixmap on screen using an accelerator.
.TP
.BR vga_fillblt (3)
- fill rectangular area in video memory with a single color.
.TP
.BR vga_hlinelistblt (3)
- draw horizontal scan lines.
.TP
.BR vga_imageblt (3)
- copy a rectangular pixmap from system memory to video memory.
.TP
.BR vga_blitwait (3)
- wait for any accelerator operation to finish.

.SS Controlling VC switches
.TP
.BR vga_lockvc (3)
- disables virtual console switching for safety.
.TP
.BR vga_unlockvc (3)
- re-enables virtual console switching.
.TP
.BR vga_oktowrite (3)
- indicates whether the program has direct access to the SVGA.
.TP
.BR vga_runinbackground (3)
- enable running of the program while there is no VGA access.
.TP
.BR vga_runinbackground_version (3)
- returns the version of the current background support.

.SS Debugging aids
.TP
.BR vga_dumpregs (3)
- dump the contents of the SVGA registers.
.TP
.BR vga_gettextfont "(3), " vga_puttextfont (3)
- get/set the font used in text mode.
.TP
.BR vga_gettextmoderegs "(3), " vga_settextmoderegs (3)
- get/set the vga state used in text mode.
.TP
.BR vga_flip (3)
- toggle between text and graphics mode.
.TP
.BR vga_setflipchar (3)
- set the character causing a vga_flip().
.PD
.PP

.SH 4. OVERVIEW OF SUPPORTED SVGA CHIPSETS AND MODES
.SS VGA and compatibles

320x200x256, and the series of 16-color and non-standard
planar 256 color modes supported by VGAlib, as well as
720x348x2.

.SS ALI2301

Supports 640x480x256, 800x600x256, 1024x768x256 SVGA modes

.SS AT3D (AT25)

Also known as Promotion at25. Popular as the 2D part of a voodoo rush card. As of this
writing there are a few known problems with this driver. Read below.

.SS ARK Logic ARK1000PV/2000PV

Full support, limited RAMDAC support. Only ARK1000PV
tested. Supports Clocks and Ramdac lines in config file.

.SS ATI SVGA (VGA Wonder and friends)

This is no real driver. I do not support any new modes.
However it saves additional card setup and thus allows use
of the plain VGA modes even when you are using non standard
text modes. It is possible to enforce use of this driver
even on ATI Mach32 but not very useful.

.SS ATI Mach32

The driver by Michael Weller supports all ATI BIOS-defined
modes and more... It hits the best out of your card.
Some modes may not have nice default timings but it uses
the ATI's EEPROM for custom config or allows to specify modes
in
.BR libvga.config (5).
Some problems may occur with quite some
third party cards (usually on board) Mach32 based controllers
as they do not completely conform to the Mach32 data sheets.
Check out
.BR svgalib.mach32 (7)
(and
.BR libvga.config (5)).

.SS ATI Mach64 (rage)

A driver for ATi Mach64 based cards with internal DAC.

.SS Chips and Technologies chipsets 65525, 65535, 65546, 65548, 65550, and 65554 (usually in laptops).

This server was written using the SVGALIB patch from Sergio
and Angelo Masci as a starting point. This version of the code
resembled the XFree server code that was used up to XFree
3.1.2. As such it was incapable of programming the clocks,
using linear addressing, Hi-Color, True-Color modes or the
hardware acceleration. All of these features have since been
added to the code.
The 64200 and 64300 chips are unsupported, however these
chips are very similar to the 6554x chips which are supported.

.SS Cirrus Logic GD542x/3x

All the modes, including 256 color, 32K/64K color,
16M color (3 bytes per pixel) and 32-bit pixel 16M color
modes (5434). Some bitblt functions are supported.
The driver doesn't work with mode dumps, but uses a SVGA
abstraction with mode timings like the X drivers.

.SS Genoa(?) GVGA6400 cards.

Supported.

.SS Hercules Stingray 64/Video

Is supported as an ARK2000PV

.SS NV3 driver for the Riva128.

This driver was written by Matan Ziv-Av and is derived
from the XFree86 driver by David J. Mckay. It lacks 24bit modes (can the
card do them at all?), acceleration support and pageflipping in
threeDKit is broken.

.SS Oak Technologies OTI-037/67/77/87

Driver by Christopher Wiles; includes 32K color modes
for OTI-087.

.SS S3

The driver is not complete, but should work on a number of
cards/RAMDACs, and 640x480x256 should work on most card. The
best support is for a 801/805 with AT&T20C490-compatible
RAMDAC, and S3-864 + SDAC.  All 256/32K/64K/16M works for
them (within the bounds of video memory & ramdac
restrictions).

The supported cards include S3 Virge and S3 Trio64 cards.

None of the acceleration function is supported yet.

The chip level code should work with the 964/868/968, but
most likely the card they come on would use an unsupported
ramdac/clock chip.  Support for these chips is slowly being
added.

Clocks and Ramdac lines in
.BR libvga.config (5)
supported.

The maximum pixel clock (in MHz) of the ramdac can be
set using a
.B Dacspeed
line in the config file. A reasonable default
is assumed if the
.B Dacspeed
line is omitted.
.B Clocks
should be the same as in XFree86. Supported
ramdac IDs:
.BR Sierra32K ", " SC15025 ", " SDAC ", " GenDAC ", " ATT20C490 ", " ATT20C498 ", " IBMRGB52x .

Example:
.br
.B Clocks 25.175 28.3 40 70 50 75 36 44.9 0 118 77 31.5 110 65 72 93.5
.br
.B Ramdac att20c490
.br
.B DacSpeed 85

Also supported, at least in combination with the
SC15025/26A ramdac, is the ICD 2061A clock chip.
Since it cannot be autodetected you need to define it
in the config file using a
.B Clockchip
line. As there is
no way to read the current settings out of the 2061, you
have the option to specify the frequency used when switching
back to text mode as second argument in the
.B Clockchip
line. 

This is especially required if your text mode is an 132
column mode, since these modes use a clock from the clock
chip, while 80 column modes use a fixed clock of 25 MHz.
The text mode frequency defaults to 40 MHz, if omitted.

Example:
.br
.B ClockChip icd2061a 40.0

.SS Trident TVGA 8900C/9000 (and possibly also 8800CS/8900A/B) and also TVGA 9440

Derived from tvgalib by Toomas Losin. TVGA 9440 support by ARK <ark@lhq.com, root@ark.dyn.ml.or>.

Supports 640x480x256, 800x600x256, 1024x768x256 (interlaced and non-interlaced)
Might be useful to add 16-color modes (for those equipped with a 512K TVGA9000)
for the 8900 and 9000 cards.

320x200x{32K, 64K, 16M}, 640x480x{256, 32K, 64K,
16M}, 800x600x{256, 32K, 64K, 16M}, 1024x768x{16, 256}, 800x600x{16, 256, 32K,
64K} modes are supported for the TVGA 9440.

Autodetection can be forced with a:

.RS
.B chipset TVGA
.I memory flags
.RE

line in the config file.

.I memory
is the amount of VGA memory in KB,
.I flags
is composed of three bits:
.RS
.TP
.B bit2 = false, bit1 = false
force 8900.
.TP
.B bit2 = false, bit1 = true
force 9440.
.TP
.B bit2 = true, bit1 = false
force 9680.
.TP
.B bit0 = true
force noninterlaced.
.TP
.B bit0 = false
force interlaced which only matters on 8900's with at least 1M
since there is no 512K interlaced mode on the 8900 or any of the other cards.
.RE

.SS Tseng ET4000/ET4000W32(i/p)

Derived from VGAlib; not the same register values.
ET4000 register values are not compatible; see
.BR svgalib.et4000 (7).

Make sure the colors are right in hicolor mode; the vgatest
program should draw the same color bars for 256 and hicolor
modes (the DAC type is defined at compilation in
.I et4000.regs
or the dynamic
registers file).
ET4000/W32 based cards usually have an AT&T or Sierra 
15025/6 DAC. With recent W32p based cards, you might have
some luck with the AT&T DAC type.
If the high resolution modes don't work, you can try
dumping the registers in DOS using the program in the
.I et4000/
directory and putting them in a file
.RI ( /etc/vga/libvga.et4000
is parsed at runtime if
.B DYNAMIC
is defined in
.IR Makefile.cfg
at compilation (this is default)).

Supported modes are
640x480x256, 800x600x256, 1024x768x256,
640x480x32K, 800x600x32K, 640x480x16M, etc.

Reports of ET4000/W32i/p functionality are welcome.

There may be a problem with the way the hicolor DAC register
is handled; dumped registers may use one of two timing
methods, with the value written to the register for a
particular DAC for a hicolor mode (in vgahico.c) being
correct for just one of the these methods. As a consequence
some dumped resolutions may work while others don't.

.SS Tseng ET6000

Most modes of which the card is capable are supported.  The 8 15
16 24 and 32 bit modes are supported.

The ET6000 has a built in DAC and there is no problem coming from
that area. The ET6000 is capable of acceleration, but this as well as
sprites are not yet implemented in the driver. 

The driver now uses modelines in libvga.config for user defined modes.
It is sometimes useful to add a modeline for a resolution which does
not display well.  For example, the G400x600 is too far to the right
of the screen using standard modes.  This is corrected by including
in 
.B libvga.config 
the line

Modeline "400x600@72"  25.000 400  440  488  520   600  639  644  666

More examples are given below.

This driver was provided by Don Secrest.

.SS VESA

Please read README.vesa and README.lrmi in doc subdirectory of the standard
distribution.

Go figure! I turned off autodetection in the release,
as a broken bios will be called too, maybe crashing the machine. Enforce
.B VESA
mode by putting a
.B chipset VESA
in the end of your
.IR libvga.config (5).

Note that it will leave protected mode and call the cards bios opening the door to
many hazards.

.SH 5. DETAILED COMMENTS ON CERTAIN DEVICE DRIVERS
This section contains detailed information by the authors on certain
chipsets.

.SS AT3D (AT25)
Also known as Promotion at25. Popular as the 2D part of a voodoo rush
card.
   
I have written a driver for this chipset, based on the XF86 driver for
this chipset.
   
The programs that work with this driver include all the programs in
the demos directory, zgv and dvisvga (tmview).
   
I believe it should be easy to make it work on AT24, AT6422.
   
.SS ATI Mach32
Please see
.BR svgalib.mach32 (7).

.SS ATI Mach64
The rage.c driver works only on mach64 based cards with internal DAC.
The driver might misdetect the base frequency the card uses, so if when setting
any svgalib modes the screen blanks, or complains about out of bound frequencies,
or the display is unsynced, then try adding the option
.BR RageDoubleClock
to the config file.
 
.SS Chips and Technologies chipsets 65525, 65535, 65546, 65548, 65550, and 65554 (usually in laptops).
Please see
.BR svgalib.chips (7).

.SS Tseng ET4000/ET4000W32(i/p)
Please see
.BR svgalib.et4000 (7).

.SS Tseng ET6000
I have only 2 Mbytes of memory on my ET6000 card, so I am not able to
get all possible modes running. I haven't even tried to do all of the
modes which I am capable of doing, but I am confident that I can
manage more modes when I have time. I have enough modes working to
make the card useful, so I felt it was worth while to add the driver
to svgalib now.

Linear graphics is working on this card, both with and without
BACKGROUND enabled, and vga_runinbackground works.

I decided it was best to quit working on more modes and try to get
acceleration and sprites working.

My et6000 card is on a PCI bus.  The card will run on a vesa bus, but
since I don't have one on my machine I couldn't develop vesa bus
handling.  I quit if the bus is a vesa bus.

I check for an et6000 card, which can be unequivocally identified. The
et4000 driver does not properly identify et4000 cards. It thinks the
et6000 card is an et4000, but can only run it in vga modes.

I have found the following four modelines to be useful in
.B libvga.config
or in
.B ~/.svgalibrc
for proper display of some modes.

.br
Modeline "512x384@79" 25.175 512 560 592 640  384 428 436 494
.br
Modeline "400x300@72" 25.000 400 456 472 520  300 319 332 350 DOUBLESCAN
.br
Modeline "512x480@71" 25.175 512 584 600 656  480 500 510 550
.br
Modeline "400x600@72" 25.000 400 440 488 520  600 639 644 666

Don Secrest <secrest@uiuc.edu> Aug 21, 1999


.SS Oak Technologies OTI-037/67/77/87
First a few comments of me (Michael Weller <eowmob@exp-math.uni-essen.de>):

As of this writing (1.2.8) fixes were made to the oak driver by
Frodo Looijaard <frodol@dds.nl> to reenable OTI-067 support. It is unknown
right now if they might have broken OTI-087 support. The author of the '87
support Christopher Wiles <wileyc@moscow.com> owns no longer an OTI-087 card and
can thus no longer give optimal support to this driver. Thus you might be
better off contacting me or Frodo for questions. If you are a knowledgeable
OTI-087 user and experience problems you are welcome to provide fixes.
No user of a OTI-087 is currently
known to me, so if you are able to fix problems with the driver please do so
(and contact me) as noone else can.

Michael.

Now back to the original Oak information:

The original OTI driver, which supported the OTI-067/77 at 640x480x256, 
has been augmented with the following features:

.TP
.B 1)
Supported resolutions/colors have been expanded to 640x480x32K,
800x600x256/32K, 1024x768x256, and 1280x1024x16.
.TP
.B 2)
The OTI-087 (all variants) is now supported.  Video memory is 
correctly recognized.
.PP

The driver as it exists now is somewhat schizoid.  As the '87 
incorporates a completely different set of extended registers, I found it 
necessary to split its routines from the others.  Further, I did not have 
access to either a '67 or a '77 for testing the new resolutions.  If 
using them causes your monitor/video card to fry, your dog to bite you, 
and so forth, I warned you.  The driver works on my '87, and that's all I 
guarantee.  Period.

Heh.  Now, if someone wants to try them out ... let me know if they work.

New from last release:

32K modes now work for 640x480 and 800x600.  I found that the Sierra DAC 
information in VGADOC3.ZIP is, well, wrong.  But, then again, the 
information for the '87 was wrong also.

64K modes
.B do not
work.  I can't even get Oak's BIOS to enter those modes.

I have included a 1280x1024x16 mode, but I haven't tested it.  My monitor 
can't handle that resolution.  According to the documentation, with 2 
megs the '87 should be able to do an interlaced 1280x1024x256 ... again, 
I couldn't get the BIOS to do the mode.  I haven't 2 megs anyway, so 
there it sits.

I have included routines for entering and leaving linear mode.  They 
.B should
work, but they don't.  It looks like a pointer to the frame 
buffer is not being passed to SVGALIB.  I've been fighting with this one 
for a month.  If anyone wants to play with this, let me know if it can be 
make to work.  I've got exams that I need to pass.

Tidbit: I pulled the extended register info out of the video BIOS.  When 
the information thus obtained failed to work, I procured the OTI-087 data 
book.  It appears that Oak's video BIOS sets various modes incorrectly 
(e.g. setting 8-bit color as 4, wrong dot clock frequencies, etc.).  Sort 
of makes me wonder ...

Christopher M. Wiles (a0017097@wsuaix.csc.wsu.edu)
.br
12 September 1994

.SH 6. GOALS

I think the ability to use a VGA/SVGA graphics resolution in one
virtual	console, and being able to switch to any other virtual console
and back makes a fairly useful implementation of graphics modes in
the Linux console.

Programs that use
.B svgalib
must be setuid root. I don't know how
desirable it is to have this changed; direct port access can hardly
be done without. Root privileges can now be given up right after
initialization. I noticed some unimplemented stuff in the kernel
header files that may be useful, although doing all register I/O via
the kernel would incur a significant context-switching overhead. An
alternative might be to have a pseudo
.I /dev/vga
device that yields
the required permissions when opened, the device being readable by
programs in group vga.

It is important that textmode is restored properly and reliably; it
is fairly reliable at the moment, but fast console switching back
and forth between two consoles running graphics can give problems.
Wild virtual console switching also sometimes corrupts the contents
of the textmode screen buffer (not the textmode registers or font).
Also if a program crashes it may write into the area where the saved
textmode registers are stored, causing textmode not be restored
correctly. It would be a good idea to somehow store this information
in a 'safe' area (say a kernel buffer). Note that the
.BR vga_safety_fork (3)
thing has the same idea.

Currently, programs that are in graphics mode are suspended while
not in the current virtual console. Would it be a good idea to let
them run in the background, virtualizing framebuffer actions (this
should not be too hard for linear banked SVGA modes)? It would be
nice to have, say, a raytracer with a real-time display run in the
background (although just using a separate real-time viewing
program is much more elegant).

Anyone wanting to rewrite it all in a cleaner way (something with
loadable kernel modules shouldn't hurt performance with linear
framebuffer/vgagl type applications) is encouraged.

Also, if anyone feels really strongly about a low-resource and
truecolor supporting graphical window environment with cut-and-paste,
I believe it would be surprisingly little work to come up with a
simple but very useful client-server system with shmem, the most
useful applications being fairly trivial to write (e.g. shell
window,	bitmap viewer).	And many X apps would port trivially.

This is old information, please be sure to read
.BR svgalib.faq (7)
if you are interested in further goals.

.SH 7. REFERENCES

The latest version of svgalib can be found on
.IR sunsite.unc.edu " in " /pub/Linux/libs/graphics
or
.IR tsx-11.mit.edu " in " /pub/linux/sources/libs
as
.IR svgalib-X.X.X.tar.gz .
As of this writing the latest version is
.IR svgalib-1.4.1.tar.gz .
There are countless mirrors of these ftp servers in the world. Certainly
a server close to you will carry it.

The original VGAlib is on
.IR tsx-11.mit.edu ", " pub/linux/sources/libs/vgalib12.tar.Z .
.I tvgalib-1.0.tar.Z
is in the same directory.

SLS has long been distributing an old version of VGAlib.
Slackware keeps a fairly up-to-date version of svgalib, but it
may be installed in different directories from what svgalib likes
to do by default. The current svgalib install tries to remove most
of this. It also removes
.IR /usr/bin/setmclk " and " /usr/bin/convfont ,
which is a security risk if setuid-root. Actually the recent makefiles try to do
a really good job to cleanup the mess which some distributions make.

If you want to recompile the a.out shared library, you will need the
DLL 'tools' package (found on
.IR tsx-11.mit.edu ", " GCC " dir)."
To make it work with recent ELF compiler's you actually need to hand patch it. You
should probably not try to compile it. Compiling the ELF library is deadly simple.

And here is a list of other references which is horribly outdated.
There are many more svgalib applications as well as the directories might have changed.
However, these will give you a start point and names to hunt for on CD's or in
ftp archives.

.SS Viewers (in /pub/Linux/apps/graphics/viewers on sunsite.unc.edu):

.PD 0
.TP
.B spic
Picture viewer; JPG/PPM/GIF; truecolor; scrolling.
.TP
.B zgv
Full-featured viewer with nice file selector.
.TP
.B see-jpeg
Shows picture as it is being built up.
.TP
.B mpeg-linux
svgalib port of the Berkeley MPEG decoder (mpeg_play); it also includes an X binary.
.TP
.B flip
FLI/FLC player (supports SVGA-resolution).
.PD
.PP
.SS Games (in /pub/Linux/games on sunsite.unc.edu):

.PD 0
.TP
.B bdash
B*lderdash clone with sound.
.TP
.B sasteroids
Very smooth arcade asteroids game.
.TP
.B yatzy
Neat mouse controlled dice game.
.TP
.B vga_cardgames
Collection of graphical card games.
.TP
.B vga_gamespack
Connect4, othello and mines.
.TP
.B wt
Free state-of-the-art Doom-like engine.
.TP
.B Maelstrom
A very nice asteroids style game port from Mac.
.TP
.B Koules
A game. (I've no idea what it looks like)
.PD
.PP
.SS Docs
In the vga directory of the
.B SIMTEL MSDOS
collection, there is a
package called
.I vgadoc3
which is a collection of VGA/SVGA register
information.

The XFree86 driver sources distributed with the link-kit may be
helpful.

.SS Miscellaneous

There's an alternative RAW-mode keyboard library by Russell Marks for
use with
.B svgalib
on
.IR sunsite.unc.edu .

.BR LIBGRX ,
the extensive framebuffer library by Csaba Biegl distributed
with
.BR DJGPP ,
has been ported to Linux. Contact Hartmut Schirmer
(phc27@rz.uni-kiel.d400.de, subject prefix "HARTMUT:"). A more
up-to-date port by Daniel Jackson (djackson@icomp.intel.com) is on
.IR sunsite.unc.edu .

The vgalib ghostscript device driver sources can be found on
.IR sunsite.unc.edu ", " /pub/Linux/apps/graphics .
Ghostscript patches from Slackware:
.IR ftp.cdrom.com ", " /pub/linux/misc .
.B gnuplot
patches are on
.IR sunsite.unc.edu .

Mitch D'Souza has written font functions that work in 16 color modes
and can use VGA textmode (codepage format) fonts; these can be found
in his
.B g3fax
package in
.IR sunsite.unc.edu .
These functions may go into a later
version of
.BR svgalib .

.SH 8. KNOWN BUGS
This section is most probably outdated, none of these problems are no longer
reported.

Using a 132 column textmode may cause graphics modes to fail. Try
using something like 80x28.

The console switching doesn't preserve some registers that may be
used to draw in planar VGA modes.

Wild console switching can cause the text screen to be corrupted,
especially when switching between two graphics consoles.

On ET4000, having run XFree86 may cause high resolution modes to
fail (this is more XFree86's fault).

The Trident probing routine in the XFree86 server may cause standard
VGA modes to fail after exiting X on a Cirrus. Try putting a 'Chipset'
line in your Xconfig to avoid the Trident probe, or use the link kit
to build a server without the Trident driver. Saving and restoring
the textmode registers with savetextmode/textmode (restoretextmode)
should also work. [Note: svgalib now resets the particular extended
register, but only if the Cirrus driver is used (i.e. the chipset
is not forced to VGA)] [This is fixed in XFree86 v2.1]

Some Paradise VGA cards may not work even in standard VGA modes. Can
anyone confirm this?

Piping data into a graphics program has problems. I am not
sure why. A pity, since zcatting a 5Mb FLC file into flip on a 4Mb
machine would be fun.

The
.B tseng3.exe
DOS program include as source in the svgalib distribution doesn't recognize any modes on
some ET4000 cards.
Also ET4000 cards with a Acumos/Cirrus DAC may only work correctly
in 64K color mode.

.SH FILES
.IR /etc/vga/libvga.config
.br
.IR /etc/vga/libvga.et4000

.SH SEE ALSO
.BR svgalib.et4000 (7),
.BR svgalib.chips (7),
.BR svgalib.mach32 (7),
.BR vgagl (7),
.BR libvga.config (5),
.BR 3d (6),
.BR accel (6),
.BR bg_test (6),
.BR eventtest (6),
.BR forktest (6),
.BR fun (6),
.BR keytest (6),
.BR lineart (5),
.BR mousetest (6),
.BR joytest (6),
.BR mjoytest (6),
.BR scrolltest (6),
.BR speedtest (6),
.BR spin (6),
.BR testaccel (6),
.BR testgl (6),
.BR testlinear (6),
.BR vgatest (6),
.BR plane (6),
.BR wrapdemo (6),
.BR convfont (1),
.BR dumpreg (1),
.BR fix132x43 (1),
.BR restorefont (1),
.BR restorepalette (1),
.BR restoretextmode (1),
.BR runx (1),
.BR savetextmode (1),
.BR setmclk (1),
.BR textmode (1),
.BR mach32info (1).

.SH AUTHOR
There are many authors of svgalib. This page was edited by
Michael Weller <eowmob@exp-math.uni-essen.de>.
The original documentation and most of
.B svgalib
was done by Harm Hanemaayer <H.Hanemaayer@inter.nl.net> though.