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.
Essential for text selection and editing in cases where mapping from the
input text to the actual shaped glyphs is nontrivial. I.e., in case of
HarfBuzzFont; both FreeTypeFont and StbTrueTypeFont perform a 1:1
translation from input (UTF-8) characters to glyphs so there it isn't
as important.
This is going to get called from fillGlyphCache() that takes a string,
and thus should be better than one virtual call per character. The
single-character variant still stays, as it's a nice convenience API.
Eventually glyphSize() will get a similar treatment as well.
Took me quite a while to realize what was going on, but in retrospect
it's obvious -- the rasterizer just *rounds* the sub-pixel-positioned
glyph quads to nearest pixels. Which then can cause the neighboring
glyph data to leak to it (because the texture is then sampled not
directly on the edge pixel, but slightly outside of it), or it can also
cut away the edge, when it gets rounded in the other direction.
This was a problem with the original -- laughably inefficient -- atlas
packer as well, but because that packer had excessive padding around
everything, only the second edge-cutting artifact manifested, and that
one is rather subtle unless you know what to look for.
This means the packing is now slightly worse than before and sizes that
previously worked may no longer fit anymore. But since the new atlas
packer is relatively new (well, from September, time sure flies
different here), and the improvement compared to the original packer is
still quite massive, I don't think this is a problem.
In basically all cases it's two independent operations so forcing them
to be done together doesn't really bring any potential efficiency
advantages. On the other hand, splitting them allows allows the caller
to better make use of available memory, as the new
renderGlyphQuadsInto() allows the input and output arrays to be aliased.
Bumping AbstractFont plugin interface versions as this is a breaking
change.
The awful original STL-heavy public API is kept the same for now, it's
just the internals being now implemented using brand new APIs that are
actually usable with multiple fonts, font sizes and runs with different
scripts/languages/directions. There's also preparation for configurable
vertical text layouting, although for now the functionality asserts that
horizontal text is used.
This also makes Renderer.h header available on non-GL builds, as the new
APIs don't rely on a class full of GL objects anymore. The class will
get eventually renamed and moved to a dedicated RendererGL.h header, but
for now this partial update has to suffice.
So it's possible to shape the text even before having all glyphs ready.
That's one reason, second reason is that this is a more common behavior
-- it usually doesn't make sense to make the text jump based on whether
it's "zaxaca", "KEKEKE" or "yqpyq".
The original alignment based on glyph bounds is now moved into dedicated
`*GlyphBounds` variants. Additionally the `*LeftGlyphBounds` were
changed to subtract the initial glyph offset as well, `*Integer` now
rounds only in the direction where it's needed because a division by 2
happened, and there's a set of `*Bottom*` values that somehow weren't
there before.
Still not good enough regression testing for the changes I need to make.
This was absolutely not verifying correct behavior of the other vertical
alignment values for multiline text.
Replaces the previous, grossly inefficient AbstractLayouter which was
performing one virtual call per glyph (!). It's now also reusable,
meaning it doesn't need to be allocated anew for every new shaped text,
and it no longer requires each and every font plugin to implement the
same redundant glyph data fetching from the glyph cache, scaling etc. --
all that is meant to be done by the users of AbstractShaper, i.e.
Renderer. The independency on a glyph cache theorerically also means it
can be used for a completely different, non-texture-based way to render
text (such as direct path drawing directly on the GPU), although I won't
be exploring that path now.
It also exposes an interface for specifying script, language,
direction and typographic features. Such interface will be currently
only implemented in HarfBuzz, but that's the intent -- to provide a
flexible enough interface to support all possible use cases that a font
or a font plugin may support, instead of exposing a least common
denominator and then having no easy way to shape a text in a non-Latin
script or use a fancy OpenType feature the chosen font has.
The old public interface is preserved for backwards compatibility,
marked as deprecated, however the virtual APIs are not, as supporting
that would be too nasty. I don't think any user code ever implemented a
font plugin so this should be okay.
To ensure smooth transition with no regressions, the Renderer class and
MagnumFont tests still use the old API in this commit, and their test
pass the same way as they did before (except for two removed MagnumFont
test cases which tested errors that are now an assertion in the
deprecated layout() API and thus cannot be tested from the plugin
anymore). Porting them away from the deprecated API will be done in
separate commits.
It was all just way too random and completely detached from real-world
cases. In particular, the mesh rectangle and the texture rectangle were
completely different, which just cannot happen, and was completely
disregarding presence of a glyph cache, making it impossible to adapt to
the upcoming AbstractLayouter / AbstractShaper rework.
It now also explicitly verifies behavior of various Alignment values
instead of just testing them at random, and there's also a new TODO
related to those.
It won't contain just font metrics anymore. Also don't require the
struct to be zero-initialized if opening fails -- simply allow the
plugins to return garbage in that case and save the values only if
opening actually succeeded.
Strictly speaking this isn't an ABI change as the return value isn't
part of the function signature and the struct is still the same, so the
plugin interface version isn't bumped for this change.
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).
Allows the Font and FontConverter plugins be built without TARGET_GL
enabled. That was the last piece missing for making the magnum-plugins
repo completely GL-free.
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.
103% of use cases use the returned value directly without checking, so
we might as well do the check ourselves. Added new function hasCurrent()
and added deprecated backward-compatibility conversion and -> operators.
Wow, that creeped to a lot of places.
Last dinosaur from the pointer age.
Similarly to what's now done with NoInit tags for Containers::Array and
all math types such as Vector, there's now NoCreate tag for creating
wrappers without actually creating the underlying OpenGL object. The
instance is then equivalent to moved-from state. Useful to avoid
needless creation/deletion of OpenGL object in case you would overwrite
the instance later anyway:
Mesh mesh{NoCreate};
std::unique_ptr<Buffer> indices, vertices;
std::tie(mesh, indices, vertices) = MeshTools:compile(...);
I wanted to preserve the parameter-less constructor of tests, but WINAPI
requires fairly ugly entagled set of functions, passing HWND around,
which required storing it in a global var and hoping it is properly
initialized when querying it for it to be passed to application
constructor.
When this was done, it was now fairly easy to support passing also
argv/argc to application constructor, which in the future will enable
selective disabling of extensions for even better test coverage.
This however needed slightly different main() function and thus we now
have MAGNUM_GL_TEST_MAIN() instead of CORRADE_TEST_MAIN(). Using the
latter will result in an assert inside std::optional.
`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