Headless OpenGL Rendering using SSH and X11 forwarding

[James Jones]

If that's the case, yes, I can confirm the NV driver does not support 
rendering with remote X servers using EGL, with or without indirect GLX 
support enabled in said server, and yes, EGLDevice will work just fine 
in that situation for offscreen rendering if you're trying to use the 
local GPU.

Thanks,
-James

On 3/13/23 18:27, Adam Jackson wrote:
> 12290 is indeed EGL_BAD_ACCESS, and it's pretty much impossible for 
> Mesa's eglInitialize to return that, so (if I had to guess) you have 
> nvidia's driver installed as well, and (extra guessing now) nvidia's EGL 
> only works with connections to the local machine and not over the 
> network. Mesa shouldn't have that problem because it would select 
> llvmpipe instead of a native driver in that scenario, I think.
> 
> If "render to png" really is what you're trying to accomplish you might 
> do better to use EGL_EXT_platform_device to get a direct connection to 
> the GPU without involving a display server.
> 
> - ajax
> 
> On Tue, Mar 7, 2023 at 8:17 PM Richard Haney <compsci2011 at gmail.com 
> <mailto:compsci2011 at gmail.com>> wrote:
> 
>     Please help,
> 
>     I have been going around and around with this problem but cannot
>     seem to make any headway. I hope that one of you OpenGL EGL experts
>     can help.:slight_smile:
> 
>     I have created a program that uses OpenGL EGL (version 1.5) with
>     OpenGL 3 that successfully renders an offscreen triangle and saves
>     it to an image file (PNG) when Issh/without/X11 forwarding on my
>     Linux (Ubuntu 22.04) machine.
> 
>     However when I try the same thing usingssh/with/X11 forwarding
>     enabled I get the following EGL error when I calleglInitialize(…):
>     12290 (I/think/isEGL_BAD_ACCESS).
> 
>     This seems really weird and I hope it is something simple that I am
>     just not currently seeing.
> 
>     I really like using OpenGL with EGL but need a way to remedy this
>     situation if possible. Is there a way for EGL to determine if X11
>     forwarding is being employed and to ignore it or some other solution?
> 
>     The snippet of relevant C++ code follows, with area where error
>     occurs marked:
> 
>     #include <iostream>#include <cstdlib>#include <EGL/egl.h>#define
>     EGL_EGLEXT_PROTOTYPES#define GL_GLEXT_PROTOTYPES#include
>     <EGL/eglext.h>#include <GL/gl.h>... EGLDisplay display =
>     eglGetDisplay(EGL_DEFAULT_DISPLAY); if(display == EGL_NO_DISPLAY) {
>     std::cerr << "Failed to get EGL display: "<< eglGetError() <<
>     std::endl; exit(EXIT_FAILURE); } EGLint major; EGLint minor;
>     if(eglInitialize(display, &major, &minor) == EGL_FALSE) { // ERROR
>     12290 is generated herestd::cerr << "Failed to initialize EGL: "<<
>     eglGetError() << std::endl; exit(EXIT_FAILURE); } ...
> 
> 
>     Any help would be greatly appreciated.
>