diff options
authorBrian Paul <>1998-10-03 12:48:50 +0000
committerBrian Paul <>1998-10-03 12:48:50 +0000
commit3867fa4cfabcb3209ebea244f61c0553079a2ecb (patch)
parenta6922cb8c35cb7eb9ac531b5c2ab5dd584aca245 (diff)
added info about overlay planes
1 files changed, 13 insertions, 4 deletions
diff --git a/docs/README.X11 b/docs/README.X11
index 538ebabdea4..0e037b37ffa 100644
--- a/docs/README.X11
+++ b/docs/README.X11
@@ -163,7 +163,7 @@ X Display Modes:
$ export MESA_RGB_VISUAL="PseudoColor 8"
-Double buffering (X11 only):
+Double buffering:
Mesa can use either an X Pixmap or XImage as the backbuffer when in
double buffer mode. Using GLX, the default is to use an XImage. The
MESA_BACK_BUFFER environment variable can override this. The valid
@@ -177,7 +177,7 @@ Double buffering (X11 only):
your application.
-Colormaps (X11 only):
When using Mesa directly or with GLX, it's up to the application writer
to create a window with an appropriate colormap. The aux, tk, and GLUT
toolkits try to minimize colormap "flashing" by sharing colormaps when
@@ -192,7 +192,7 @@ Colormaps (X11 only):
variable MESA_PRIVATE_CMAP. The value isn't significant.
-Gamma correction (X11 only):
+Gamma correction:
To compensate for the nonlinear relationship between pixel values
and displayed intensities, there is a gamma correction feature in
Mesa. Some systems, such as Silicon Graphics, support gamma
@@ -231,6 +231,15 @@ Gamma correction (X11 only):
+Overlay Planes
+ Overlay planes in the frame buffer are supported by Mesa but require
+ hardware and X server support. To determine if your X server has
+ overlay support you can test for the SERVER_OVERLAY_VISUALS property:
+ xprop -root | grep SERVER_OVERLAY_VISUALS
HPCR glClear(GL_COLOR_BUFFER_BIT) dithering
If you set the MESA_HPCR_CLEAR environment variable then dithering
@@ -304,4 +313,4 @@ Summary of X-related environment variables:
-$Id: README.X11,v 3.1 1998/07/29 01:19:15 brianp Exp $
+$Id: README.X11,v 3.2 1998/10/03 12:48:50 brianp Exp $