added NUL driver for DMesa
diff --git a/docs/README.DJ b/docs/README.DJ
index ed7f8c8..0ec3622 100644
--- a/docs/README.DJ
+++ b/docs/README.DJ
@@ -111,7 +111,7 @@
Q) I made a simple application and it does nothing. It exits right away. Not
even a blank screen.
- A) The pure software drivers (VESA/VGA) support only double-buffered modes.
+ A) Pure software drivers (VESA/VGA/NUL) support only double-buffered modes.
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 ;-).
@@ -126,6 +126,13 @@
from `Mesa/src/glut/dos/Makefile.DJ' before (re)making GLUT. Beware, this
means you will never EVER be able to safely use `glut.dxe'!
+ Q) What is NUL driver good for, if I don't get any output at all?
+ A) For debugging. The NUL driver is very much like OSMesa. Everything is
+ done just the same as VESA/VGA drivers, only it doesn't touches your
+ video hardware. You can query the actual buffer by issuing:
+ DMesaGetIntegerv(DMESA_GET_BUFFER_ADDR, &buffer);
+ and dump it to a file.
+
Q) How do I query for a list of available video modes to choose as a visual?
A) This is an ugly hack, for which I'm sure I'll burn in hell.
First, query for a list of modes:
@@ -189,7 +196,11 @@
with small windows, set initial position far to the right (or way down); then
you can move them back to any position right before the main loop.
-The following environment variables can customize GLUT behaviour:
+
+
+Environment variables:
+~~~~~~~~~~~~~~~~~~~~~~
+ DMESA_NULDRV - (any value) force NUL driver
GLUT_FPS - print frames/second statistics to stderr
DMESA_GLUT_REFRESH - set vertical screen refresh rate (VESA3)
DMESA_GLUT_BPP - set default bits per pixel (VGA needs 8)
@@ -248,6 +259,7 @@
x more changes to the 3dfx driver
v1.6 (???-2004)
+ + implemented NUL driver
+ added DMesaGetProcAddress and glutGetProcAddress
! fixed a horrible bug in VGA initialization routine