glumpy Geom-Path Throwing Error 1280

Am trying to implement a geometry shader in my current project, so decided to try the geom-path example. Unfortunately the same thing happens to geom-path as in my own geometry shader tests - this error is thrown.

I am using: cython-0.29 glumpy-1.0.6 numpy-1.15.3 triangle-20170429

[w] Cannot read STENCIL size from the framebuffer
[i] Using GLFW (GL 3.0)
[i] Running at 60 frames/second
Traceback (most recent call last):
  File "geometry_shader_example.py", line 348, in <module>
    app.run()
  File "/usr/local/lib/python3.6/dist-packages/glumpy/app/__init__.py", line 302, in run
    clock = __init__(clock=clock, framerate=framerate, backend=__backend__)
  File "/usr/local/lib/python3.6/dist-packages/glumpy/app/__init__.py", line 262, in __init__
    window.dispatch_event('on_resize', window._width, window._height)
  File "/usr/local/lib/python3.6/dist-packages/glumpy/app/window/event.py", line 394, in dispatch_event
    if getattr(self, event_type)(*args):
  File "/usr/local/lib/python3.6/dist-packages/glumpy/app/window/window.py", line 219, in on_resize
    self.dispatch_event('on_draw', 0.0)
  File "/usr/local/lib/python3.6/dist-packages/glumpy/app/window/event.py", line 384, in dispatch_event
    if handler(*args):
  File "geometry_shader_example.py", line 342, in on_draw
    program.draw(gl.GL_LINE_STRIP_ADJACENCY_EXT, I)
  File "/usr/local/lib/python3.6/dist-packages/glumpy/gloo/program.py", line 592, in draw
    self.activate()
  File "/usr/local/lib/python3.6/dist-packages/glumpy/gloo/globject.py", line 86, in activate
    self._create()
  File "/usr/local/lib/python3.6/dist-packages/glumpy/gloo/program.py", line 175, in _create
    self._build_shaders(self._handle)
  File "/usr/local/lib/python3.6/dist-packages/glumpy/gloo/program.py", line 223, in _build_shaders
    shader.activate()
  File "/usr/local/lib/python3.6/dist-packages/glumpy/gloo/globject.py", line 86, in activate
    self._create()
  File "/usr/local/lib/python3.6/dist-packages/glumpy/gloo/shader.py", line 216, in _create
    self._handle = gl.glCreateShader(self._target)
  File "/usr/local/lib/python3.6/dist-packages/OpenGL/error.py", line 232, in glCheckError
    baseOperation = baseOperation,
OpenGL.error.GLError: GLError(
	err = 1280,
	description = b'invalid enumerant',
	baseOperation = glCreateShader,
	cArguments = (GL_GEOMETRY_SHADER_EXT,),
	result = 0
)

Nov 01 '18 21:11 thomfoster

Do you know what is your system and GL driver ?

Nov 03 '18 07:11 rougier

I am running Ubuntu 18.04.1 LTS

OpenGL ES profile version string: OpenGL ES 3.0 Mesa 18.0.5 OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.00

Nov 03 '18 12:11 thomfoster

Can you try without the_EXT?

Nov 03 '18 18:11 rougier

How would I go about doing that? thanks for all the help so far

Nov 03 '18 19:11 thomfoster

You'll have to (temporarily) modify glumpy sources in glumpy/gloo/shader.py.

Nov 03 '18 20:11 rougier

Do you mean changing the following line:

def __init__(self, code=None, vertices_out=0, input_type=None, output_type=None):
        Shader.__init__(self, gl.GL_GEOMETRY_SHADER_EXT, code)

to

def __init__(self, code=None, vertices_out=0, input_type=None, output_type=None):
        Shader.__init__(self, gl.GL_GEOMETRY_SHADER, code)

No success with that, same error as before.

Nov 03 '18 20:11 thomfoster

Yes, it is was I meant. Can you try code from https://github.com/rougier/glsl-experiments and check if the geometry shader one works?

Nov 03 '18 21:11 rougier

Sadly same error as before, with and without the _EXT

Nov 03 '18 22:11 thomfoster

Despite changing the gloo/shader.py file I notice that in the error message I still have mentions of _EXT.

Traceback (most recent call last):
  File "geometry_shader_example_experiment.py", line 315, in <module>
    geometry = gl.glCreateShader(GL_GEOMETRY_SHADER_EXT)
  File "/usr/local/lib/python3.6/dist-packages/OpenGL/error.py", line 232, in glCheckError
    baseOperation = baseOperation,
OpenGL.error.GLError: GLError(
	err = 1280,
	description = b'invalid enumerant',
	baseOperation = glCreateShader,
	cArguments = (GL_GEOMETRY_SHADER_EXT,),
	result = 0
)

Changing Line 315 to

geometry` = gl.glCreateShader(GL_GEOMETRY_SHADER)

I get this error:

Traceback (most recent call last):
  File "geometry_shader_example_experiment.py", line 315, in <module>
    geometry = gl.glCreateShader(GL_GEOMETRY_SHADER)
NameError: name 'GL_GEOMETRY_SHADER' is not defined

Nov 03 '18 22:11 thomfoster

Can you try on the console a glxinfo (or something like this) to check if your driver reports geometry shader extension?

Nov 04 '18 06:11 rougier

Interesting - no mention of geometry shaders in glxinfo. Ran glxinfo | grep "geometry" just to make sure and no output. Do I need to upgrade my version of openGL or is this a hardware issue? I'm running ubuntu as a virtual machine, might that be making a difference?

Nov 04 '18 16:11 thomfoster

Ouch, yes, that might be a reason. The first few lines of glxinfo shoudl report what is the driver for GL. If it is indirect, that's not good (emulated through Mesa probably).

Nov 04 '18 17:11 rougier

Think I'm definitely running it through Mesa, my OpenGL Version Sring is 3.0 Mesa 18.0.5.

Is all hope lost or is there something I can do?

Nov 04 '18 18:11 thomfoster

The important part is whether you have direct rendering (access to GPU) or not. If not then I don't see any solution using the virtual machine. What it your host system?

Nov 04 '18 20:11 rougier