Preparing for the soon-to-be-merged KTX files. Not hooking up 1D/3D and
the compressed APIs yet, doing that only when the plugins get merged so
I have a way to test.
To avoid combinatorial explosion of functions that have to be
implemented on the plugin side, the single-image variants proxy to the
multi-level variants, if available.
THe plugin interface string had to be bumped because otherwise there was
a *really nasty* silent ABI break where instead of doSetFlags() it was
suddenly calling doConvert().
Minor but very important convenience feature, especially useful when
dealing with command-line apps. This now works:
magnum-imageconverter a.png a.jpg -c jpegQuality=0.75
The AnyImageConverter gets the jpegQuality option and then
automatically propagates it to the concrete plugin (which is either
JpegImageConverter or StbImageConverter), possibly warning in case the
target plugin doesn't recognize given option (i.e., doesn't list it in
its default configuration). Previously the user had to always specify a
concrete converter implementation using -C, which was rather annoying
and nonintuitive.
First and foremost I need to expand the interface to support 3D
image conversion. But the interface was not great to begin with, so this
takes the opportunity of an API break and does several things:
* The `export*()` names were rather strange and I don't even remember
why I chose that name (maybe because at first I wanted to have an
"exporter" API as a counterpart to importers?)
* In addition, there was no way to convert a compressed image to a
compressed image (or to an uncompressed image) and adding the two
missing variants would be a lot of combinations. So instead the new
convert() returns an ImageData, which can be both, and thus also
allows the converters to produce compressed or uncompressed output
based on some runtime setting, without having to implement two
(four?) separate functions for that and requiring users to know
beforehand what type of an image will be created.
* The ImageConverterFeature enum was named in a really strange way as
well, with ConvertCompressedImage meaning "convert to a compressed
image" while "ConvertCompressedData" instead meant "convert a
compressed image to a data". Utter chaos. It also all implied 2D and
on the other hand had a redundant `Image` in the name, so I went and
remade the whole thing. As mentioned above, two of the enums now mean
the same thing, and are both replaced with Convert2D.
* Finally, similarly as changes elsewhere, I took this opportunity to
get rid of std::string in the convertToFile() APIs.
The current testing workflow had quite a few major flaws and it was no
longer possible after the move of Any* plugins to core. Among the flaws
is:
* Every plugin was basically built twice, once as the real plugin and
once as a static testing library. Most of the build shared common
object files, but nevertheless it inflated build times and made the
buildsystem extremely complex.
* Because the actual plugin binary was never actually loaded during the
test, it couldn't spot problems like:
- undefined references
- errors in metadata files
- mismatched plugin interface/version, missing entry points
- broken static plugin import files
* Tests that made use of independent plugins (such as TgaImageConverter
test using TgaImporter to verify the output) had a hardcoded
dependency on such plugins, making a minimal setup very hard.
* Dynamic loading of plugins from the Any* proxies was always directed
to the install location on the filesystem with no possibility to
load these directly from the build tree. That caused random ABI
mismatch crashes, or, on the other hand, if no plugins were
installed, particular portions of the codebase weren't tested at all.
Now the workflow is the following:
* Every plugin is built exactly once, either as dynamic or as static.
* The test always loads it via the plugin manager. If it's dynamic,
it's loaded straight from the build directory; if it's static, it
gets linked to the test executable directly.
* Plugins used indirectly are always served from the build directory
(if enabled) to ensure reproducibility and independence on what's
installed on the filesystem. Missing presence of these plugins causes
particular tests to be simply skipped.
* Plugins that have extensive tests for internal functionality that's
not exposed through the plugin interface are still built in two
parts, but the internal tests are simply consuming the OBJECT files
directly instead of linking to a static library.
Vladimír Vondruš