GLSL/OpenGL shader compile failure

[Colin Arnott]

Currently I am receiving the following error from icesl when I launch:

[FATAL] 

**** GLSL shader failed to compile (vertex) ****

0:2(10): error: GLSL 4.20 is not supported. Supported versions are: 1.10, 1.20, 1.30, 1.00 ES, and 3.00 ES

I do not think I am missing any dependencies, and I am unclear what dependency has version 4.20. Can anybody assist?

I am experiencing this on Linux, and have reproduced it with both Ubuntu 17.04 and Arch Linux.

[Maze Mietner]

To me it looks like IceSL tries to use a OpenGL 4.2 function, and that's missing on your computer. What's your OpenGL version, glxinfo should give this info?
For IceSL you need to have at least OpenGL 4.3.

[Colin Arnott]

running the following command:

glxinfo | grep OpenGL | grep "version string"

gives me this output: (more can be provided, but it was quite a lot)

OpenGL core profile version string: 3.3 (Core Profile) Mesa 17.1.8

OpenGL core profile shading language version string: 3.30

OpenGL version string: 3.0 Mesa 17.1.8

OpenGL shading language version string: 1.30

OpenGL ES profile version string: OpenGL ES 3.0 Mesa 17.1.8

OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.00

Now, graphics libraries are not my wheelhouse, but I would have thought that installing up to date mesa and freeglut (plus the other deps) would be sufficient. Also, this is not working on both my ubuntu and arch linux (rolling release distro) systems (both were updated as part of this install), so I am unclear how mesa is so far behind. Also the *.deb installed fine on ubuntu, so I would have expected there not to be any version issues.

[sylefeb]

Hi Colin,

I have never tried to run IceSL on Mesa and I am unsure whether it would work (and with reasonable performance). Afaik Mesa is a software implementation of OpenGL and does not use the GPU.

The best is to install, if possible, the drivers from your GPU vendor, e.g. NVidia or AMD drivers. We use mostly NVidia hardware under Linux and their drivers work very well.

However, before anything, could you please let us know the specs of your graphics hardware so we can check if it supports OpenGL 4.x ?

Best regards,
Sylvain

[Maze Mietner]

>

OpenGL core profile version string: 3.3

It's OpenGL 3.3, not enough to run IceSL.

I don't know what to tweak to support OpenGL 4.5, I'd guess at least this here:
https://www.wilderssecurity.com/threads/tutorial-making-mesa-display-opengl-4-5-instead-of-4-3.389258/

Maze

[Jérémie Dumas]

Mesa is an open-source implementation of OpenGL, and afaik this is the
official driver for Intel GPU (as well as newer AMD GPUs from what I
gather online).

Mesa has long been stuck on OpenGL 3.3 (until 2015), but they now
support OpenGL 4.5 and some features of OpenGL 4.6. So my guess is that
you have older hardware that doesn't support recent OpenGL
implementations.

Not that IceSL requires "only" OpenGL 4.2 (not 4.3). Which is why it
doesn't work on Mac (which only supports up to OpenGL 4.1).

[Colin Arnott]

hmm, that would make sense, this is an older system (sandybridge); thanks a bunch for identifying what is going go. do I have any options (as mesa appears to have hardware requirements for newer opengl versions)?

[Jérémie Dumas]

Well ... you should probably buy a new GPU =)
You can find older GPU which are OpenGL 4.2+ enabled for quite cheap I think.

Mesa also provides a software rasterizer, but I don't know if it's
OpenGL 4.2+ capable, and it's likely to be slow anyway ...

[Colin Arnott]

makes sense; unfortunately my current env is a laptop, so that may be tricky.

[Maze Mietner]

Did you try this (replace program with IceSL), what's the result?

env MESA_GLSL_VERSION_OVERRIDE=450 env MESA_GL_VERSION_OVERRIDE=4.5COMPAT /usr/bin/program

[Colin Arnott]

progress but no success:

[FATAL] 

**** GLSL shader failed to compile (fragment) ****

0:3(12): warning: extension `GL_ARB_gpu_shader5' unsupported in fragment shader

0:4(12): warning: extension `GL_ARB_shader_image_load_store' unsupported in fragment shader

0:26(2): error: `gl_FragColor' undeclared

0:26(2): error: value of type vec4 cannot be assigned to variable of type error

0:82(2): error: `gl_FragColor' undeclared

0:82(2): error: value of type vec4 cannot be assigned to variable of type error

It looks like versions 4.3 - 4.5 give the error above, 4.2 and below all have version not supported errors.

[Maze Mietner]

Then you'll need additional chipset drivers, MESA does support this - but only with some kind of hardware acceleration (first column green, next three for software only are red), see: https://mesamatrix.net/
Unless you can get a chipset and driver that is supported by MESA it won't work.

[Colin Arnott]

That makes sense; thanks everybody for all the great help, it was both enlightening and responsive. If I ever do get IceSL running on a different machine, I will make sure to give back to the community.

[sylefeb]

Hi Colin,

I hope you will be able to use IceSL in the near future. I'll also try to update the online version http://shapeforge.loria.fr/icesl-online/ (it should run in Firefox without trouble) - it has been falling behind a bit because of our limited development time... This is a light version of IceSL but for many parts it is sufficient. Let me know if you start using it, it will be good motivation to update it :)

Best,
Sylvain

[sylefeb]

Hi Colin,

It just occurred to me, if you are primarily interested in slicing, you can use slicecrafter: http://shapeforge.loria.fr/slicecrafter/
This is the equivalent of IceSL-slicer 2.1.3, it only lacks the thickness optimizer which uses the GPU.

Sylvain

[Colin Arnott]

Cool, I will take a look.