Previous fix didn't work well enough because on Windows Python has different
environment than Blender ans setting variables in there made no effect from
Blender point of view.
This means render devices now might skip building baking kernels in cases when
only actual render-related functionality is used.
For now it's only implemented for OpenCL split kernel device and mainly needed
to work around some compiler-specific bugs which crashes on building the kernel.
Using OpenCL for baking might still crash the driver, but at least there is now
higher probability of that GPU will be usable to render the scene.
Real fix should actually be done in the driver side.
The idea is to make all kernels as small as possible to work around possible
issues with buggy drivers which might fail building feature-complete kernels.
It's indeed just a workaround to make at last simple test scenes to render
on OpenCL. Real fix should happen from the driver side.
Requires having latest El Capitan beta 3 OSX due to ome crucial fixes made in the
compiler. Supports same features as NVidia OpenCL apart from CMJ (there's no
experimental feature set support in megakernel yet).
Uses megakernel internally, which works much better than the split kernel. Split
kernel is not supported on OSX still, needs to be investigated still.
Some more details can be found there:
http://wiki.blender.org/index.php/Dev:2.6/Source/Render/Cycles/OpenCL#AMD_on_OSX
This is not really supported by OpenCL but might happen in certain
configurations. There might be some remained cases when this happens
but so far can not find any,
It was annoying copy-paste happened across OpenCL device constructor, device
enumeration and split kernel checks. Now those areas are using an utility
function which returns pairs of platform and device IDs for devices which are
supported by Cycles and enumeration is happening inside that list.
This makes it so filtering is happening in a single place, so there's no need
to keep 3 different functions in sync.
This commit also fixes a bug with wrong enumeration of devices caused by recent
fixes. Those fixes were in fact wrong and only happened to appear to be working
on laptop with optimus card on Linux. Root of those issues is in fact in bad
Linux driver for optimus cards.
They'll be checked for the version later and that check will fail anyway,
so better to not allow user to see unsupported device in the list.
Also corrected one more issue with the device enumeration.
Skipped devices did not reflect in the device number, which might result in bad
array indices.
This might also resolve T45037, and need to be ported to a release branch.
Round-up was only enabled for viewport render, which was for a long time hardcoded to
use 64 closures. This was done in order to avoid unnecessary kernel re-compilations
when tweaking the shader tree.
We could enable selective closure compilation in the viewport later if it'll give
measurable speed improvements, but even then round-up is to happen outside of the
device level,
This commit also removes early output which happened in cases when max closure did
not change. It was wrong because other requested kernel features might have been
changed.
This features are now based on the scene settings, so scenes without those features
used are rendered even faster.
This gives about 30% speedup on the AMD A10 APU here, but at the same time it does
not mean such an improvement will happen on all the hardware. That being said, the
Tonga device here seems to have no measurable difference.
In any case it seems handy to have for the future, when we'll want to support SSS
in the kernel or to port selective compilation/split kernel to CUDA devices.
For now it's reported to the stdout, matching to the CUDA behavior.
In the future we can hide this into GLog logging once the kernels
are considered all stable and so.
Since the kernel split work we're now having quite a few of new files, majority
of which are related on the kernel entry points. Keeping those files in the
root kernel folder will eventually make it really hard to follow which files are
actual implementation of Cycles kernel.
Those files are now moved to kernel/kernels/<device_type>. This way adding extra
entry points will be less noisy. It is also nice to have all device-specific
files grouped together.
Another change is in the way how split kernel invokes logic. Previously all the
logic was implemented directly in the .cl files, which makes it a bit tricky to
re-use the logic across other devices. Since we'll likely be looking into doing
same split work for CUDA devices eventually it makes sense to move logic from
.cl files to header files. Those files are stored in kernel/split. This does not
mean the header files will not give error messages when tried to be included
from other devices and their arguments will likely be changed, but having such
separation is a good start anyway.
There should be no functional changes.
Reviewers: juicyfruit, dingto
Differential Revision: https://developer.blender.org/D1314
They were lost during simplification of kernel loading but might be rather
crucial for the performance.
Also made it so cflags are shared across kernels. Surely it might lead to
some unwanted kernel re-compilation but at the same time they might easily
run out of sync with the changes in kernel and so.
Experimental feature set id currently unavailable for megakernel, it'll
require some changes to the cache system to distinguish cached regular
kernels from cached experimental kernels.
Currently unused, but some features will be enabled soon.
This required allocating some memory related on object transform needed
by ShaderData and currently it is done for all the platforms. Since we're
targeting full feature-complete platforms this is rather acceptable at
this point and in the future we'll do selective NO_HAIR/NO_SSS/NO_BLUR
kernels.
This is experimental still and in fact there're some major issues on
NVidia platform and it's not really clear if it's a bug in compiler,
some uninitizlied variable or other kind of issue.
Some stupid fixes like spaces around operator and missing semicolon,
plus fix for wrong detecting of ShaderData SOA size. Thar was harmless
since there's only one closure array, but still better to fix this.
This file was actually checking for features enabled on CPU and surely all
of them were enabled, so removing them does not cause any difference.
ideally we'll need to do runtime feature detection and just pass some stuff
as NULL to the kernel, or maybe also have variadic kernel entry points which
is also possible quite easily.
No need to store them in the class, they're unlikely to be changed
and if they do change we're in big trouble anyway.
More appropriate approach would be then to typedef this things in
kernel_types.h, but still use inlined sizeof(),
Only those ones are priority for now, all the rest are still testable
if CYCLES_OPENCL_TEST or CYCLES_OPENCL_SPLIT_KERNEL_TEST environment
variables are set.
This commit contains all the work related on the AMD megakernel split work
which was mainly done by Varun Sundar, George Kyriazis and Lenny Wang, plus
some help from Sergey Sharybin, Martijn Berger, Thomas Dinges and likely
someone else which we're forgetting to mention.
Currently only AMD cards are enabled for the new split kernel, but it is
possible to force split opencl kernel to be used by setting the following
environment variable: CYCLES_OPENCL_SPLIT_KERNEL_TEST=1.
Not all the features are supported yet, and that being said no motion blur,
camera blur, SSS and volumetrics for now. Also transparent shadows are
disabled on AMD device because of some compiler bug.
This kernel is also only implements regular path tracing and supporting
branched one will take a bit. Branched path tracing is exposed to the
interface still, which is a bit misleading and will be hidden there soon.
More feature will be enabled once they're ported to the split kernel and
tested.
Neither regular CPU nor CUDA has any difference, they're generating the
same exact code, which means no regressions/improvements there.
Based on the research paper:
https://research.nvidia.com/sites/default/files/publications/laine2013hpg_paper.pdf
Here's the documentation:
https://docs.google.com/document/d/1LuXW-CV-sVJkQaEGZlMJ86jZ8FmoPfecaMdR-oiWbUY/edit
Design discussion of the patch:
https://developer.blender.org/T44197
Differential Revision: https://developer.blender.org/D1200
