Like with TextureTools::DistanceField, to make room for non-GL
implementations. Old names are deprecated aliases, same for headers. The
only remaining bit in the Text library is the Renderer class, but for
that one I first need to invent a non-shitty API so I can just deprecate
the old thing as a whole and create something reasonable from scratch in
RendererGL.
The internal GL texture format (especially the R8 vs Luminance mess on
ES2) is now considered an implementation detail and shouldn't affect
common use in any way.
The format is now required always, in order to prepare for use cases
where colored glyphs are a thing as well. Additionally, to match the
recent change in AbstractGlyphCache, the processed format is specified
separately, allowing the input and processed formats to be decoupled.
Which ultimately fixes the regression on ES2 and WebGL 1 where it was no
longer possible to call font.fillyGlyphCache() on a
DistanceFieldGlyphCache.
Also, as there's now a generic format on input, another ES2-specific
issue is now fixed as well, in particular a case where a GL error
would be emitted on drivers with EXT_texture_storage because an unsized
format is passed to setStorage(). This was a problem since a long time
ago, but I ignored it because it didn't affect WebGL 1 and all drivers
that exposed EXT_texture_storage exposed EXT_texture_rg, effectively
circumventing this issue. Or so I think, at least.
The constructors taking either a GL::TextureFormat or no format at all
are now deprecated aliases to the new functionality.
The class now supports incremental filling, multiple fonts, texture
arrays, removes all reliance on STL containers and is finally properly
documented.
To avoid complete breakage of every use, as much as possible was kept as
deprecated APIs -- in particular the reserve() with the nasty
std::vectors, the insert() that assumes a 2D cache and a single font
and textureSize() that returns a 2D vector. Those behave the same as
before, but will assert if the cache is an array or contains more than
one font.
On the other hand, begin() / end() access with std::unordered_map iterators
(ew!) was removed as the internals simply aren't a hashmap anymore. The
image() that returned an Image2D is now used to fill the glyph cache
instead of querying its potentially processed contents, and returns a
MutableImageView3D. I considered keeping it and adding sourceImage()
instead, but such naming turned out to be too inconsistent. For querying
processed image data (such as with the distance field cache) there's a
new processedImage() query, guarded by new GlyphCacheFeature bits -- if
both ImageProcessing and ProcessedImageDownload is set, it can be used
to retrieve the processed image (so, similar as ImageDownload was
before), and if neither is set, the cache contents are queryable
directly through image(), without needing any special support from
the GPU API.
Existing code is updated only in the minimal way possible to ensure that
no serious breakage was introduced by reimplementing the deprecated APIs
on top of the new backend. Porting away from deprecated APIs will be
done in next commits. The GlyphCache and DistanceFieldGlyphCache have
their public API kept intact for now, as a similar rework will be needed
for them as well.
Additionally, the MagnumFont and MagnumFontConverter plugins aren't
compiling yet as they require substantial changes to deal with the new
glyph cache features. That is not the case with other plugins in the
magnum-plugins repository tho, for those the backwards compatibility
"just works". On the other hand, since layout of the AbstractGlyphChange
changed, I'm bumping the AbstractFont plugin interface version to
force-trigger a rebuild of dependent projects. Because I ran a stale
magnum-player binary, it worked without crashing or GL errors but just
didn't show ANY text whatsoever due to ABI differences, and I wasted
some precious minutes before realizing that a simple rebuild would fix
it.
All std::string arguments are now a StringView, what returned a
std::pair is now a Pair. STL compatibility headers are included on
deprecated builds to ease porting, as usual.
The only *really* breaking changes are in the internals, where an
ArrayView<const char32_t> is used instead of std::u32string, which is in
line with the change done in Utility::Unicode::utf32(); and a Triple is
returned instead of a std::tuple. Behaviorally nothing changed except
that fillGlyphCache() now asserts if the input string contains invalid
UTF-8 (which is also in line with the cahnge done in Utility::Unicode).
This means I (and people making their own plugins) don't need to go and
update each and every plugin once the version in the interface string
gets bumped after a (silent) ABI break. Such as when new virtual
functions get added, as those often lead to strange crashes if the
plugins don't get rebuilt after.
The plugins will now use this macro, which means they'll
automatically embed an interface string that was present in the base
class header at build time. However, when the base class updates, the
previous string is still embedded in the plugin binary, which will then
fail to load -- this being automatic doesn't mean the original purpose
is lost. Subsequently rebuilding the plugins from source will make them
pick up the updated interface string again.
Having code snippets in docs compiled and checked for syntax and
outdated API errors is great. In theory. In practice the people reading
docs have NO IDEA how much needless suffering goes into making the
compiler collaborate with me on such a seemingly simple task. UGH.
Like in Trade, the unatomic exists() + read() pair (and silent failures
if the file exists but can't be read) was replaced with just
Path::read() that now returns an Optional. Besides that, not much worth
mentioning.
Basically mirroring the API of Trade::AbstractImporter, as that proved
to be useful. The old crazy openSingleData() and openData(horribleStuff)
are deprecated and will be removed in a future release.
No backwards compatibility is provided for font plugins, these need to
be adapted.
This better reflects that the functions modify a global state instead of
a shader-local state and so rebinding may be necessary (unlike with
uniforms, which get preserved).
The old set*() functions are now inline aliases to the bind*()
functions, are marked as deprecated and will be removed in some future
release.
Vladimír Vondruš