Standard naming convention for shaders

Question

Is there a "best" naming convention for shaders? If not, what are the popular options?

For example

*.vert *.vertex *.vsh

*.frag *.pixel *.fsh *.psh

I dont have examples for geometry and tesselation

Answer 1

The reference GLSL compiler recognizes these extensions :

Usage: glslangValidator [option]... [file]...

'file' can end in .<stage> for auto-stage classification, where <stage> is:
    .conf   to provide a config file that replaces the default configuration
            (see -c option below for generating a template)
    .vert   for a vertex shader
    .tesc   for a tessellation control shader
    .tese   for a tessellation evaluation shader
    .geom   for a geometry shader
    .frag   for a fragment shader
    .comp   for a compute shader
    .mesh   for a mesh shader
    .task   for a task shader
    .rgen    for a ray generation shader
    .rint    for a ray intersection shader
    .rahit   for a ray any hit shader
    .rchit   for a ray closest hit shader
    .rmiss   for a ray miss shader
    .rcall   for a ray callable shader
    .glsl   for .vert.glsl, .tesc.glsl, ..., .comp.glsl compound suffixes
    .hlsl   for .vert.hlsl, .tesc.hlsl, ..., .comp.hlsl compound suffixes

Answer 2

I think the reason why there's such a variety of names to choose from is because, according to the GLSL spec, shaders aren't files, they're character strings. Strings which nearly every application loads from a file, but strings nonetheless.

That said, the authors of the Orange Book in their sample applications have settled upon .vert and .frag. I think that's a pretty meaningful vote. I also think it strikes the right note between succinct (moreso than .fragment) and legible (moreso than .fsh).