Mesa (3D support not present on OLPC).

[edsiper]

Xorg in Build122 is trying to load a missed glx module:

Section "Module" # Load "dbe"

Load "extmod"
Load "fbdevhw"
Load "glx"

# Load "record"

Load "freetype"

# Load "type1"

Load "evdev"

EndSection

X Log:

(II) LoadModule: "glx"
(WW) Warning, couldn't open module glx
(II) UnloadModule: "glx"
(EE) Failed to load module "glx" (module does not exist, 0)

[jg]

We need to get an opinion on whether having Mesa in software is worth it or not. Will it enable any useful applications (we know it won't perform well)?

[jg]

I'm leaving this here (with a better title), in case someone can come up with a case for having software 3D support (Mesa) on the system.

IMHO, this should be decided by people with real applications needing it (which perform adequately) as the existence proof.

[ajax]

Just a note to myself or anyone else who ends up wanting to package this, if we ever do:

It's unlikely to be useful to do actual GLX support unless the machine actually has 3D hardware. Mesa's X11 driver is likely to be much more performant (client side rasterisation to XImage) than indirect GLX protocol. The appropriate Mesa build target is 'linux' for this, not 'linux-indirect' or 'linux-dri'.

[jg]

Ah, good point, Ajax. I'll leave this here in case someone comes up with an interesting application that needs 3D support sooner rather than later, but is low enough performance that software rendering is feasible. Such applications do exist, but we shouldn't expend the effort until the time comes, as we have more urgent fish to fry.

I won't close it because then someone might open a new bug, and we'd lose this train of thought. I'll also fix the summary to make it clear it is not GLX support that is interesting.

Now, edsiper bothered to open this bug: I wonder if he has the existence proof of an application that should motivate this sooner.

[bill_mcgonigle]

I did a bit of hacking on the fedora mesa packages to get it to build the 'linux' target (thanks for the tip, ajax). There appears to have been some bit-rot on the non-DRI packaging in the Fedora mesa SRPMS (filenames, selinux support, etc) so I had to do a bit of patching here and there. I'm not 100% positive it's perfect, but it compiles, builds, and runs. I'm sure it's not ready to be checked into anything.

My hardware here is a PIC running the 20070507 devel-ext3 image booting to the develboard target. Performance on glxgears is about 50 fps. For quick comparison, my MacBook Pro runs about 4500fps.

The OpenGL app I wanted to run (homegrown) is dreadfully slow, but I'm just learning OpenGL programming. There are also other OpenGL software renderers which aim for speed - Mesa aims for correctness.

I put the packages up here in case anybody is interested:

http://bfccomputing.com/downloads/olpc/mesa/

[bill_mcgonigle]

Replying to edsiper:

(II) LoadModule: "glx"
(WW) Warning, couldn't open module glx
(II) UnloadModule: "glx"
(EE) Failed to load module "glx" (module does not exist, 0)

Oh, just to clarify, with the software-renderer ('linux target') there's no need to load the GLX module in xorg.conf.

[bernie]

We disabled GLX since X 1.4.

I think we can close this bug as WONTFIX.