We now build three gltfio libraries:
- gltfio_core ....... lightweight library with ubershaders
- gltfio ............ uses filamat to generate materials at runtime
- gltfio_pipeline ... depends on path tracer functionality
This works by aliasing CUSTOM0 - CUSTOM7 to morphing attributes, and by
extending our existing skinning variant.
This PR was tested against some upcoming changes to gltfio.
Issue #1149, #1417
When processing very high dynamic range environments, the importance
sampling code falls appart, it becomes a user choice to decide if
prefilter importance sampling is better or worse than just regular
importance sampling -- both are usually bad.
--ibl-no-prefilter gives the user this choice.
In the case where we have 2 cores, we would spawn only one thread in
the thread pool. If that thread got to try to steal() from another
thread before the main thread was adopted, it would end-up always
trying to steal from itself and enter an infinite loop.
This seems to happen during windows builds.
This combines two constants into one, and changes it into a value that
is actually correct. :)
Technically the movement of the CUSTOM attributes will change the layout
qualifier and therefore merits a materials version bump, however custom
attributes were only recently introduced so this seems unnecessary.
Did some quick testing with 3 samples: gltf_viewer, lucy_bloom, and
point_sprites.
Clamping is now disabled by default in cmgen, there is a new option
to enable it "--clamp".
Automatic SH windowing is also enabled by default and can be controled
with the "--sh-window" option. Accepted parameters are "no" to disable
windowing, "auto" for automatic windowing or a number to specify the
cutoff band.
auto windowing only works for 1, 2, and 3 bands.
Currently we're arbitrarily clamping environments to 16384 because both
the pre-filtering and SH algorithms can't handle very larger dynamic
ranges. Instead of clamping, we now tonemap, which is a little bit better.
It turns out that most of libmath couldn't be used in constexpr
expression due to our use of union{}. The C++ standard requires that
all accesses to a union{} in a constexpr expression be the same
element.
Also because libm and cmath are not constexpr some functions such
as length() or normalize() can't be constexpr. The same is true for
anything needing things like sqrt, cos, sin, ceil, floor.
This change mainly does the following:
- replace all accesses to vector elements by operator[]
(this ensure all of libmath uses the same union element)
- avoid use of std::min / std::max / std::abs
- avoid uninitialized variables, which can't be constexpr
- remove 'constexpr' keyword on functions that can never be
It is now possible to write things like:
constexpr mat4f I = inverse(
transpose(mat4f::translation(float3{ 1, 2, 3 })
* mat4f::scaling(4)));
--sh-window=band, -w band : this low-pass-filters the environment
such that bands above 'band' are zero. This can be used to reduce ringing
when the source environment has high frequencies
--noclamp : turns off clamping before processing the cube map
This is still work in progress.
The conversion factors from radiance to irradiance where wrong.
The bug above was found while refactoring the code to be clearer. Now
the method that computes the coefficients for the shader calls the
regular SH code and applies all the appropriate factors on that.
With this change the options "--sh-shader" and "-sh=3 -i" won't
produce the same result because --sh-shader includes the lambertian
diffuse. "--sh" now always produces actual SH coefficients.
This is a prep step for the upcoming morph feature and does not require
a bump to our material version number.
Stay tuned for a new sample app that demonstrates this feature.
this is because the JobSystem's queue works as a LIFO, by creating
jobs in reverse (memory) order, we attempt to help streaming to
the d-cache on that threads -- until the point where
jobs are stolen.
we also execute the last job immediately instead of creating a job
for it -- since we're already in a job.
- parallel_for doesn't use recursion anymore to create the "leaf"
jobs, this is now done linearly on N thread (one thread per CPU).
This uses less stack space, and reduces miss-predicted branches.
- remove almost all SYSTRACE calls because they have a huge impact
on things like parallel_for() and are misleading. They can be
enabled again by setting HEAVY_SYSTRACE to true.
- we simplify the waiting code by using only a single
condition variable instead of two.
- wait() now behaves just like a looper, it will process jobs until
the one it's waiting for finishes -- before it could just sit there
(the idea was that the job would finish quickly, but that's not always
the case).
- we also make sure to never call notify_n() when it's not needed.
We track how many waiters we have and use that to decide if we need
to notify().
notify is pretty slow on all architectures, even on linux it's always
a syscall, so it's better to avoid it.
- don't use stand-alone fences, makes things ugly for no real benefit
- refactored the code a bit, hopefully it's more clear.
If the client opts in to "recomputeBoundingBoxes", then we manually
compute a bounding box that ignores the glTF min / max annotations.
This computation was erroneously including the transform of the injected
root node, which is not part of the model.
This could cause a problem when creating the asset, then immediately
positioning it with its injected root node before the ResourceLoader
is done downloading vertex buffers.
The Work-stealing dequeue indices could wrap around after ~2 billion
calls to steal(). This could probably be achieved in a few hours.
By using 64-bits indices, we avoid the problem entirely.
This uses strtof rather than stringstream and provides a common location
that can be leveraged by the upcoming JNI bindings.
Note that this new method lives in KtxBundle rather than KtxUtility. The
latter creates Filament textures and therefore does not get built into
libimage.
For jobs with that do very little work, the jobsystem can introduce
a lot of overhead, we mitigate this by:
- don't wake-up worker threads when scheduling several very small jobs,
like when scheduling the per-face jobs.
- don't wait for per-face jobs to finish -- we only did that to avoid
a copy of the job's data.
- don't use multi-threading at all if the job has too little work. We
evaluate the work using the scanline length and number of samples.
