Mesa 5.0 DOS/DJGPP Port v1.3
			~~~~~~~~~~~~~~~~~~~~~~~~~~~~



Description:
~~~~~~~~~~~~

Well, guess what... this is the DOS port of Mesa 5.0, for DJGPP fans... Whoa!
The driver has its origins in ddsample.c, written by Brian Paul and found by me
in Mesa 3.4.2.



Legal:
~~~~~~

Mesa copyright applies, provided this package is used within Mesa. For anything
else, see GPL.



Installation:
~~~~~~~~~~~~~

Unzip and type:

	make -f Makefile.DJ [OPTIONS...]

Available options:

     Environment variables:
	CPU		optimize for the given processor.
			default = k6
	BIG_OPT=1	crazy optimizations; not very useful, though...
			default = no
	SGI_GLU=1	build SGI's GLU instead of Mesa's.
			default = no
	GLIDE		absolute path to Glide library; used with FX.
			default = $(TOP)/include/glide3
	FX=1		build for 3dfx Glide3; use it if you have the Glide
			SDK (designed for your platform), and, of course, a
			3dfx card... Note that this disables compilation of
			actual DMesa code, as Glide does all the stuff!
			default = no
	HAVE_X86=1	optimize for i386.
			default = no
	HAVE_MMX=1	MMX instructions; use only if you assembler/compiler
			supports MMX instruction set; backwards compatibility
			with older processors is still preserved.
			default = no
	HAVE_SSE=1	(see HAVE_MMX)
			default = no
	HAVE_3DNOW=1	(see HAVE_MMX)
			default = no

     Targets:
	all:		build everything
	libgl:		build GL
	libglu:		build GLU
	libglut:	build GLUT
	clean:		remove object files
	realclean:	remove all generated files



Tested on:
	CPU:		K6-2 (CXT) @500(412.5) MHz
	Mainboard:	ViA Apollo VP2/97 w/ 128 MB SDRAM
	Video card:	PowerColor EvilKing3 (Voodoo3 3000 PCI) w/ 16 MB SDRAM
	DJGPP:		djdev 2.04 + gcc v3.2 + make v3.79.1
	OS:		DOS and Win9x



FAQ:
~~~~

1. Compilation

   Q) I tried to run `make' and it exits because `gcc' complains it cannot find
      some stupid file.
   A) You need LFN support.
   A) When compiling for Glide (FX=1), pay attention to Glide path.

2. Dynamic modules

   Q) What are you mumbling about dynamic modules?
   A) You must have the DXE3 package (available on my site) installed in order
      to build the dynamic modules.

   Q) DXE3 modules give me headaches...
   A) The DXE3 modules are not compulsory. The static libraries are still built
      and you can use them in the old-fashioned, classic way... and learn to
      live with your huge executable size. For example:
	gcc -o OUT.exe IN.c -lglut -lglu -lgl

   Q) Okay, DXE3 modules are built. How can I use them?
   A) Build your export object file; then link it with your application.
      For example:
	dxe3res -o dmesadxe.c gl.dxe glu.dxe glut.dxe
	gcc -o dmesadxe.o -c -fno-builtin dmesadxe.c
	gcc -o OUT.exe dmesadxe.o IN.c -liglut -liglu -ligl -ldl

3. Using Mesa for DJGPP

   Q) DMesa is so SLOOOW! The Win32 OpenGL performs so much better...
   A) Is that a question? If you have a Voodoo3/Banshee card, you're lucky. The
      Glide port is on my web page. If you haven't, sorry; everything is done
      in software. Suggestions?

   Q) I made a simple application and it does nothing. It exits right away. Not
      even a blank screen.
   A) Single-buffered is not allowed at all. Until I can find a way to use
      *REAL* hardware acceleration, it won't get implemented.
   A) Another weird "feature" is that buffer width must be multiple of 8 (I'm a
      lazy programmer and I found that the easiest way to keep buffer handling
      at peak performance ;-).

   Q) My demo doesn't display text. I know I used the glut font routines!
   A) Then you probably use GLUT as a DXE. Well, there is no direct access to
      variables due to the way DXE works. Read the documentation. The author of
      GLUT took this into account for _WIN32 DLL's only; I don't want to modify
      his headers. The only workaround is to link GLUT the old way :-(

   Q) I tried to set refresh rate w/ DMesa, but without success.
   A) Refresh rate control works only for VESA 3.0. If you were compiling for
      Glide, see Glide info. If not, sorry!

   Q) The GLUT is incomplete.
   A) See below.



libGLUT (the toolkit):
~~~~~~~~~~~~~~~~~~~~~~

Well, this "skeletal" GLUT implementation is not mine. Thanks should go to
Bernhard Tschirren, Mark Kilgard, Brian Paul and probably others (or probably
not ;-). GLUT functionality will be extended only on an "as needed" basis.

My keyboard driver used only scancodes; as GLUT requires ASCII values for keys,
I borrowed the translation tables (and maybe more) from Allegro -- many thanks
to Shawn Hargreaves et co. Ctrl-Alt-Del (plus Ctrl-Alt-End, for Windows users)
will shut down the GLUT engine unconditionally: it will raise SIGINT, which in
turn will (hopefully) call the destructors, thus cleaning up your/my mess ;-)
NB: since the DJGPP guys ensured signal handlers won't go beyond program's
space (and since dynamic modules shall) the SIGINT can't be hooked (well, it
can, but it is useless), therefore you must live with the 'Exiting due to
signal SIGINT' message...

The mouse driver is far from complete (lack of positioning, drawing, etc), but
is enough to make almost all the demos work.

The timer is pretty versatile for it supports multiple timers with different
frequencies. While not being the most accurate timer in the known universe, I
think it's OK. Take this example: you have timer A with a very high rate, and
then you have timer B with very low rate compared to A; now, A ticks OK, but
timer B will probably loose precision!

As an addition, stdout and stderr are redirected and dumped upon exit. This
means that `printf' can be safely called during graphics. A bit of a hack, I
know, because all messages come in bulk, but I think it's better than nothing.
"Borrowed" from LIBRHUTI (Robert Hoehne).

Window creating defaults: 640x480x16 at (0,0), 8-bit stencil, 16-bit accum.
However, the video mode is chosen in such a way that first window will fit. If
you need high resolution with small windows, try to place them far to the right
(or way down).

The following environment variables can customize GLUT behaviour:
	DMESA_GLUT_REFRESH	-	set vertical screen refresh rate
	DMESA_GLUT_BPP		-	set default bits per pixel



History:
~~~~~~~~

v1.0 (mar-2002)
	initial release

v1.1 (sep-2002)
	+ added 3dfx Glide3 support
	+ added refresh rate control
	+ added fonts in GLUT
	* lots of minor changes

v1.2 (nov-2002)
	* synced w/ Mesa-4.1
	- removed dmesadxe.h

v1.3 (dec-2002)
	+ enabled OpenGL 1.4 support
	+ added MMX clear/blit routines
	+ enabled SGI's GLU compilation
	+ added color-index modes
	+ added 8bit FakeColor (thanks to Neil Funk)
	+ added VGA support (to keep Ben Decker happy)
	* fixed GLUT compilation error (reported by Chan Kar Heng)
	* overhauled virtual buffer and internal video drivers
	* better fxMesa integration
	* extended GLUT functionality
	* switched to DXE3



Contact:
~~~~~~~~

Name:   Borca Daniel
E-mail: dborca@yahoo.com
WWW:    http://www.geocities.com/dborca/