Unlike _rgb and _rgbf these are not constexpr, but I'll eventually add
table-based constexpr variants into a new ConstexprLiterals namespace
for all sRGB and half-float variants.
Improve related links for the literals, and don't say "calls" because it
doesn't do that anymore, and it'd imply it inherits the same issues with
not checking for hexadecimal colors or not checking length.
This means I don't get the parsed number as an integer but have to parse
it myself from individual chars, on the other hand it allows me to check
that it's indeed hexadecimal and has correct length, because writing a
24-bit color literal with _rgbaf, or forgetting one digit, etc. was a
common source of accidental bugs.
The new code is larger and more complex, so I verified that it doesn't
have too large effect on compile times. On GCC the MathColorTest built
in ~1.20 seconds before and ~1.25 after, on Clang it was 1.24 vs 1.26.
So there's a minor increase, but it's small enough to warrant the
increased robustness. In total, the whole codebase with tests builds in
~120 seconds both before and after, so I suppose unless the codebase
consists of just color literals alone (which could be the case for e.g.
some stylesheets), it's completely fine.
And it found bugs in some test code already. Fix for those is in next
commit.
The MAGNUM_GL_ABSTRACTSHADERPROGRAM_SUBCLASS_DRAW_IMPLEMENTATION() and
MAGNUM_GL_ABSTRACTSHADERPROGRAM_SUBCLASS_DISPATCH_IMPLEMENTATION() *is*
documented so that one stays not underscored.
Am I overdoing it? Most unpremultiplication code I found doesn't even
deal with treating alpha being zero correctly, while here I'm handling
also the cases of RGB channels going over alpha, and for packed
formats trying to match precision of the same done with pack()/unpack().
The equations were using some strange undefined `a` which made it look
like it's dealing with alpha. Just turn that into a constant like
Wikipedia does, and link there as well. Additionally, one of the `c`'s
wasn't correctly a lowercase bold vector.
Similarly as done in Aug 2024 in Corrade. When these were a part of the
function signature, they ended up being encoded into the exported
symbol. There are still cases of StridedArrayView slice() having
enable_if in the signature, which amounts to about 18 kB symbols in all
libMagnum*-d.so libraries, but apart from that this is the state before:
$ strings libMagnum*-d.so | grep enable_if | grep -v slice | wc -c
29591
And this is after. All of those are coming from STL, thus from
old or deprecated APIs that still use std::vector, std::tuple and such,
and from the few std::sort() uses.
$ strings libMagnum*-d.so | grep enable_if | grep -v slice | wc -c
4103
In a non-deprecated build it's just this, which is a 10x reduction.
Can't really do much about these maybe exceút for implementing my own
swap() specializations (sigh?), but I think it's fine.
$ strings libMagnum*-d.so | grep enable_if | grep -v slice | wc -c
2904
I also made it consistently use
typename std::enable_if<..., int>::type = 0
instead of
class = typename std::enable_if<...>::type
because the former works correctly also in presence of overloads and
having it used consistently everywhere makes it easier to grep & change
later. All SFINAE is now also excluded from Doxygen output, because it
doesn't make much sense there. It's better to just explain the
restriction in words than with this nasty hack.
Same as done for Containers::StaticArray some time ago. Since it's not a
potentially dangerous operation, it's not made as an overload of the
from() function, but instead a regular constructor. It's however kept
explicit for now, even though it eventually might not need to be -- I'm
not sure about potential consequences yet.
To allow people to cherry-pick just a subset of them if other code
defines literals that may conflict. I first did that the same way as
STL (so both namespaces inline), only to subsequently discover the
horror that all literals are implicitly available in the enclosing
Math namespace, thus preventing no conflicts at all. So the Literals
namespace isn't getting inline, only the inner ones.
This is also in preparation for introduction of
Literals::ConstexprColorLiterals that would provide a constexpr variant
of the _srgbf literals at the expense of having a large LUT in a header
file.
This complier is making my hair gray. Fortunately the out-of-class
operator doesn't conflict with the in-class one, so it's purely an
additive workaround. Adding extra checks to all subclasses to be sure
this works correctly in all cases and not just in the base class.
Except for a vector and a row matrix multiplication operator, which
doesn't make sense to be a member. These are all now significantly
shorter thanks to not having to repeat that many template parameters,
and they can make use of direct access into the _data array for better
debug perf.
Need them for the UI. Will eventually need the sRGB literals too, not
sure what to do there yet, std::pow() is only constexpr in C++26. I'll
be probably long retired when *that* version becomes the min spec for
Magnum.
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.
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.
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.
Counterparts to the sRGB-converting APIs, for when one doesn't want to
perform sRGB conversion. Or for "wrong sRGB" workflows. Named like this
and not just `fromRgbInt()` to make the calls at least a bit suspicious.
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.
Should make new things more discoverable, avoid confusion when a
documented API isn't there and reduce the need for maintaining multiple
separate versions of the docs.
Vladimír Vondruš