Despite what the standard tries to say. I bet a large portion of
<type_traits> is impossible to implement without it, which is why all
STL implementations define it there already.
There's Containers::Triple now for this instead. Printing a message to
Error in case of a failure might have made sense back in 2010, but now
it absolutely doesn't, so it's additionally wrapped in an Optional now.
Also looks like the actual use without "convenient" std::tie() is a lot
less verbose. Haha.
Using Containers::Pair allows me to make certain Range APIs constexpr
that weren't possible in C++11 before. Compared to std::pair it's also
trivially copyable, which is a nice property when storing it in various
growable containers.
As usual, the <Corrade/Containers/PairStl.h> include is in place to help
people with porting, although in many cases this change will be
breaking. I had to do it at some point anyway, so the earlier it is the
better.
Instead of defining the same types and vaguely risking little
differences. Typedefs that don't exist in Magnum.h (such as integer
quaternions) and typedefs that differ from Magnum.h (such as
using Vector<4, T> instead of Vector4<T>) stay as typedefs, to make it
clear what *deliberately* differs and what not.
Typedefs that didn't conflict with the template types in Math (such as
Vector3us) are removed entirely, as the typedef from Magnum.h can be
used directly in that case, without any `using`.
I did this back in 2010 because it "felt like the right thing to do",
given that all of Magnum depended on Math and not vice versa. But,
strictly speaking, Math already uses typedefs from Magnum/Types.h so why
it couldn't also bring in the Corrade namespace, and the
Debug/Warning/Error names too. Having to type out Corrade:: in all these
was really just a waste of time, weird inconsistency in docs and an
extra roadblock for whoever might want to contribute anything there.
Partially needed to avoid build breakages because Corrade itself
switched as well, partially because a cleanup is always good. Done
except for (STL-heavy) code that's deprecated or SceneGraph-related APIs
that are still quite full of STL as well.
The perf cost is just too great for these to be enabled always. The only
place where the assertions are kept always is in the batch APIs -- there
it's assumed the function is called on large enough data to offset this
overhead, plus since it's often dealing with large blocks of data the
memory safety is more important than various FP drifts which were the
usual case why other assertions were firing.
Similar to the change done in Corrade, see the commit for details:
878624ac36
Wow, this is probably the most backwards-compatibility code I've ever
written. Can't wait until I can drop all that.
It limits the support for CMake 3.12+, but it's much less verbose and I
don't expect people to use ancient CMake versions with IDEs like Xcode
or VS anyway, so this should be fine.
The old one is deprecated, and will be removed in a future release.
Unfortunately, to avoid deprecation warnings, all use of NoInit in the
Math library temporarily have to be Magnum::NoInit This will be cleaned
up when the deprecated alias is removed.
That one is reportedly using the more stable implementation, so just use
it. The code is then also easier to follow. Also added a matrix
decomposition test case and referencing it from the docs, in case
someone would need it again.
The test is running pretty slow on debug builds, though (sorry). I see
no way how to make it faster while still exposing the issues with
std::accumulate().
Some classes are by default constructed zero-filled while other are set
to identity and the only way to to check this is to look into the
documentation. This changes the default constructor of all classes to
take an optional "tag" which acts as documentation about how the type is
constructed. Note that this result in no behavioral changes, just
ability to be more explicit when writing the code. Example:
// These two are equivalent
Quaternion q1;
Quaternion q2{Math::IdentityInit};
// These two are equivalent
Vector4 vec1;
Vector4 vec2{Math::ZeroInit};
Matrix4 a{Math::IdentityInit, 2}; // 2 on diagonal
Matrix4 b{Math::ZeroInit}; // all zero
This functionality was already present in some ugly form in Matrix,
Matrix3 and Matrix4 classes. It was long and ugly to write, so it is
now generalized into the new Math::IdentityInit and Math::ZeroInit tags,
the original Matrix::IdentityType, Matrix::Identity, Matrix::ZeroType
and Matrix::Zero are deprecated and will be removed in the future
release.
Math::Matrix<7, Int> m{Math::Matrix<7, Int>::Identity}; // before
Math::Matrix<7, Int> m{Math::IdentityInit}; // now
It is often annoying to write e.g. this, especially in generic code:
T dot = Math::Vector<size, T>::dot(a, b);
When this is more than enough and the compiler can infer the rest from
the context:
T dot = Math::dot(a, b);
There are more downsides and confusing cases (you can call
Math::Vector<3, T>::dot(), Math::Vector3<T>::dot() and Color3::dot() and
it is still the same function), so I made these as free functions in
Math namespace. You can now also abuse ADL for the calls, but I would
advise against that for better readability:
T d = dot(a, b); // dot?! what on earth is dot? and what is a?
The only downside found when porting is that you need to specify the
type somehow when having both parameters as initializer lists:
T d = dot({2.0f, -1.5f}, {1.0f, 2.5f}); // error
T d = dot(Complex{2.0f, -1.5f}, {1.0f, 2.5f}); // okay
But that's probably reasonable (and it's also highly corner case,
the functions were used this way only in tests).
The original static member functions are of course still present, but
marked as deprecated and will be removed at some point in future.
Vladimír Vondruš