[MaulingMonkey]

Console developers don't get much choice: You pretty much must use D3D9, D3D11, GNM(X), etc.

Mobile's not much better: OpenGL ES for Android (which is a far cry from real desktop OpenGL - to the point that I consider it a completely different graphics API that just happens to confusingly reuse the names of some functions.) Maybe Metal for iOS.

Real desktop OpenGL is one of the few graphics APIs I've never been forced to use - so why spend even a single dev-month porting to it? Even games with OpenGL render paths may work better using their Direct3D renderers on Linux via Wine!

Even counting Linux/OS X, at this point I'm not even convinced OpenGL is actually the more portable API...

[jhasse]

I've written an iOS app and the OpenGL code was (except very few ifdefs) identical to the desktop code. So I wouldn't say that ES is a completely different API, you can certainly reuse a lot.

[MaulingMonkey]

Not even our shaders went unscathed - no rectangular matrix support (mat4x3? nope!), mandatory precision specifiers (lowp-highp), no Uniform Buffer Objects. Can't even call glTexImage2D on ES 2 without perfectly fine OpenGL code failing - because format !== internalFormat is forbidden (read: documented "must be the same"), and you were a good explicit OpenGL citizen and asked for something as horrifically complicated as format=GL_RGBA and internalFormat==GL_RGBA8. Multiple render targets? Are you out of your mind? We can't have that - goodbye deferred rendering, hello old school forward rendering!

Even your bread and butter - functions like glUniformMatrix3fv do things like just outright ignore the transpose parameter. This is extremely well documented: "Specifies whether to transpose the matrix as the values are loaded into the uniform variable. Must be GL_FALSE." ( https://www.khronos.org/registry/OpenGL-Refpages/es2.0/xhtml... )

I swear I've reused more code between D3D11 and PS4 codepaths than between OpenGL ES and OpenGL codepaths, and the d3d11 and ps4 APIs don't share a single common function name betwixt them!

I must assume going from OpenGL ES 2 to real OpenGL a bit easier - even if you're probably giving all the fast paths in the latter a wide berth in doing so. Or maybe OpenGL ES 3 is a bit closer to real OpenGL. But OpenGL ES 2 vs desktop OpenGL? They both render triangles, but beyond that, it's a crap-shot, and a lot of #ifdefs in my experience. Separate files, even. Not just a few.

EDIT: s/codepaths/apis/, finish summarizing my thoughts.

[pjmlp]

Yes, calling OpenGL ES "OpenGL" compatible is only true to the ears of those that never had the "fun" to write portable code across multiple GPUs.

At the end of the day, the code paths, extension support and driver workarounds are so many that one could just be coding against multiple APIs anyway.

[jhasse]

I guess you're right, as I was only using rather basic stuff (e.g. no lightning, no shaders), just framebuffers, VBOs, etc.

(replied to my own comment by accident first)

[jhasse]

I guess you're right, as I was only using rather basic stuff (e.g. no lightning, no shaders), just framebuffers, VBOs, etc.