No matter how broken iOS is in CMake 3.6, $<CONFIG> seems to work there,
so reducing the amount of code and putting the configure into a single
place independently of what generator or what system/build is used.
Compared to current state it always adds Debug/configure.h instead of
putting it directly to the ${CMAKE_CURRENT_BINARY_DIR}, but the
alternative would be some CMake branching again and I just removed that,
so no.
This also prepares everything for plugin libraries being put into a
central place -- the config files don't depend on their location
anymore.
Tested on WebGL 1 and 2, SwiftShader ES2 and ES3 and ARM Mali ES2 and
ES3 now, all pass. SwiftShader has a bit different output for zero
shininess, but that's a corner case so I'm not going to investigate
further, just adding the expected wrong output to check against as well.
Note -- since there are no visual tests for Phong yet, this is done in
the least intrusive manner to avoid breaking current functionality. It's
likely very underperforming due to the matric calculation per fragment,
it'll get optimized once I have proper tests.
Slow and ugly, is here only for making quick'n'dirty alpha masked
drawing without a need for blending or depth sorting. Oh and also to
support the glTF alpha mask feature. Again, beware: *slow*.
There will be numerous additions to this one so it made sense to make it
a static library instead of a header-only library. That also allows
CMake users to just link to Magnum::OpenGLTester instead of going
through the pain of a huge branching in order to find a correct
windowless application just to run their tests. It could have been done
even without the static library using a INTERFACE target, but that
wouldn't work on CMake < 3.0 (which, unfortunately, quite a few people
are still stuck with).
Unfortunately it's already heavily used elsewhere so I had to go through
the pain of deprecating the old implementation. The old implementation
was header-only so it can't be just typedef'd to the new one as there
would be linker failures. So the old header is just kept as it was, with
only the macros reduced.