I'm seeing an assert for null string data not being correctly thrown in
a SceneTools API on ARM64 and an overflow of this 48-bit offset seems to
be a culprit. So better have that covered in the constructor already.
That comment made no sense as it *doesn't* call into the header, just a
few lines above. Spent half a century looking for the constructor there
due to this.
I'm (again) postponing implementation of a robust & optimized
Utility::copy() for bit array views. Attempted something, but it got out
of hand very quickly. Since the particular use case here isn't going to
be a perf bottleneck I think, it's fine to do it with just a dumb loop
for now.
It'll be soon needed by other tools and library users as well. The main
difference compared to the original internal API is that the
detection for shared mapping views now takes also sizes and strides into
account, without relying on just the data pointer.
Some additional robustness checks are needed regarding fields that have
mapping sharing enforced (as otherwise it'll fail in the SceneData
constructor which isn't nice), that'll be done in subsequent commits.
The new filterAttributes() API takes a BitArray, which makes the
internals a lot simpler -- no O(n^2) lookup, no growable arrays, and no
need to duplicate the same code in the ID- and name-based variants.
For consistency with MaterialTools and soon MeshTools, the APIs are
moved to a new Filter.h header, with the deprecated variants kept only
in the original FilterAttributes.h.
This is now the preferrable way to set options to plugins that get
delegated to from other plugins, instead of
Until now there wasn't a general command line interface to pass options
to plugins that get delegated to from other plugins, such as image
converters used by scene converters. Due to that limitation, e.g.
GltfSceneConverter had to add an [imageConverter] configuration group
that it then copied over to the chosen image converter. But such
approach obviously doesn't scale -- every converter would have to do the
same, would have to repeat the whole testing process, and basically the
same would need to be done for all importers delegating to image
plugins. Nightmare.
So there's now --set, which allows arbitrary options to be set for
arbitrary plugins, and that's the preferrable way now. To avoid having
to maintain two ways to do the same, the [imageConverter] group will get
removed eventually.
The main use case is being able to specify what concrete plugin gets
used for a particular alias, e.g. to be able to use SpngImporter instead
of PngImporter for faster PNG image loading.
So far the option is implemented only here, as the imageconverter,
shaderconverter and other tools don't really deal with plugins
that delegate to other plugins. Yet.
When using the -P or -M options on a large scene, it can happen that
the conversion would fail for a small number of outliers. For example
there can be some line meshes which aren't supported by MeshOptimizer,
or there are 16-bit images not supported by a certain image conversion
plugin.
Failing the whole operation in that case may be too radical, especially
if the only alternative would be to write a Python script that deals
with the outliers in a custom way. The option simply makes the
processing step pass through the original data unchanged, which may be a
simple and good-enough solution in many of those cases.
Custom material attributes are enforced to start with a lowercase
letter, so I think it makes sense to be consistent and use the same for
custom scene fields and mesh attributes as well. It's not enforced in
any way but the tests should reflect that choice so new code that gets
written based on these inherits that practice.
Originally I thought I'd save plugins some time if I just give them the
custom indices directly, without being wrapped in a SceneField /
MeshAttribute enum. But in practice that didn't really save anything,
made the interfaces more error-prone due to there being no concrete type
anymore, and all code that delegates to nested importers or converters
had to re-wrap the IDs again, which is *again* error-prone.
Bumping the interface strings because this is a breaking change for the
implementations. Not for users tho, there nothing changes.
In some cases it's needed to release (or copy) the data first and
only then access the field properties through the SceneData to
(optionally) re-route the field views to a new data location. But since
releaseData() was implicitly erasing field data as well, this wasn't
possible and the only other option was to release the field data first
and then access them through the low-level SceneFieldData API with all
convenience lost.
This makes the release*Data() APIs a bit dangerous to use, but that
should be fine -- those aren't meant to be used by regular code anyway.
Similar caveat is with MaterialData already.
Especially the part about non-owned data was lacking, with basically no
information about what are offset-only attributes and fields actually
good for.
Instead of saying "which is not supported" in each assert, which is
vague and might imply that "it eventually will be supported", document
the actual reason in a single place, which is the MeshAttributeData docs.
It looked like it was last touched in 2012. Not great. Also, with this I
can finally stop explaining the four-byte-aligned-row defaults to people
and can just point them to docs.
Useful for creating pixel formats with different channel count,
adding/removing the sRGB bit and such. Counterpart to
vertexFormat(VertexFormat, UnsignedInt, bool) that got added back in
2020.06 already.
Doing so usually points to some error in user code, so directly disallow
it, instead of returning false. Such behavior is consistent with
pixelFormatChannelCount() and other helper APIs.
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.
The assertion message printed being/end range, which was extremely
uninformative as it didn't show sizes and strides. That form made sense
for reporting if the views weren't contained in the data arrays, but not
here.
Additionally, the existing assertion didn't check stride, which means
that a mapping with 2 items and stride 8 was treated as being equal to a
mapping with 4 items and stride 4. On the other hand, it didn't behave
correctly for offset-only fields, those were always treated as different
from pointer fields even if they were actually matching.
Vladimír Vondruš