The plugin interface version got bumped to avoid ABI issues when loading
plugins that weren't updated for the change, but apart from that this
shouldn't be a breaking change, as the API returns a type that can be
both an Optional and a Pointer.
Similar to image mip level import, but this is largely left to be
importer-specific. For example PLY defines per-face data and sometimes
one might want to import them as-is, without them being turned into a
per-vertex property.
For backwards compatibility these will delegate to the new MeshData
interfaces for 3D (and nothing for 2D, because so far there were no 2D
scene importers).
Bloaty says it saved 10 kB in Debug build of MagnumGL:
VM SIZE FILE SIZE
-------------- --------------
[ = ] 0 .debug_info +1.59Ki +0.0%
+0.4% +1.50Ki .text +1.50Ki +0.4%
[ = ] 0 .debug_str +409 +0.0%
[ = ] 0 .debug_line +276 +0.1%
[ = ] 0 .debug_abbrev +20 +0.0%
-28.6% -2 [LOAD [RX]] -2 -28.6%
[ = ] 0 [Unmapped] -4.28Ki -41.0%
-22.7% -9.23Ki .rodata -9.23Ki -22.7%
-0.8% -7.73Ki TOTAL -9.73Ki -0.1%
And 4 kB in Release:
VM SIZE FILE SIZE
-------------- --------------
+1.1% +3.44Ki .text +3.44Ki +1.1%
+1.7% +1.39Ki .eh_frame +1.39Ki +1.7%
[ = ] 0 [Unmapped] +656 +51%
-25.5% -9.47Ki .rodata -9.47Ki -25.5%
-0.7% -4.64Ki TOTAL -4.00Ki -0.4%
That's not negative, so I guess that's good. This change is of course
more significant in the context of a minimal WebGL build, where the exe
can be as little as 50 kB -- there 4 kB is almost 10% of the size.
This makes it possible to:
- finally use Magnum as a CMake subproject on Windows and have your
executables not fail to run with a "DLL missing" error (and the
setting is put to cache so superprojects just implicitly make use of
that)
- run tests on Windows without having to install first
- use dynamic plugins from a CMake subproject on any platform without
having to install first or load them by filename --- and the plugin
directory is now easily discovered as relative to
libraryLocation() of the library implementing given plugin interface
It'll get used outside of the root namespace and since the callbacks tend
to be quite complex, it would be silly to require users to implement one
callback for Trade, one for Text and one for Audio, for example.
The original implementation had a few problems:
- If a file callback was set, openFile() was unconditionally calling
right into doOpenData(), making it impossible for the importer to
know the original path for correctly supplying paths to additional
files. Now, if the importer supports Feature::FileCallback,
doOpenFile() is always called. It's also possible for the importer to
save the path and then just delegate to the base doOpenFile()
implementation -- it will handle the file callbacks correctly too.
- If the importer supported neither FileCallback nor OpenData and
callbacks were set, the original doOpenFile() implementation was
called without any warning or anything, doing silently a bad thing.
Now in this case setFileCallbacks() asserts -- programmer has to
check for feature support first.
- It was not possible for the file callback to indicate file opening
failure -- in general, empty files are valid, so a nullptr ArrayView
is also a valid file. Now the callback return an Optional instead.
And removing the bundled std::optional implementation. This finally
makes this library compatible with C++17. Since this would be a huge
backwards-incompatible change that would make everyone angry, the
following had to be done in case both CORRADE_BUILD_DEPRECATED and
MAGNUM_BUILD_DEPRECATED is defined:
* Under C++11 and C++14, Containers::Optional / Containers::NullOpt is
aliased to std::optional / std::nullopt. This is no worse than the
state before, when we also provided these symbols.
* Under C++17, where standard <optional> header is available,
Containers::Optional provides implicit conversion to it. Only one-way
conversion is supported, as there was fortunately no Magnum API that
took std::optional via parameter, and there might be some corner
cases that this doesn't cover. The goal is to have all examples
compiling with the old API, at least.
* There's a new test especially for this, which checks that both the
C++11 and C++17 ways of doing things work as they should.
The typedef and conversion is marked as deprecated, so it will spit out
many warnings to push users to upgrade. I hope I can completely remove
this mess soon :/
`char*` is now the default type for byte arrays. Results in shorter
code, less annoyances and more convenient testing. As is the case with
Corrade, I'm not doing any compatibility/deprecation layer, as most of
these functions is not widely used anyway.
Vladimír Vondruš