Issue was caused by MSVC not being able to optimize some code out in the same
way as GCC/Clang does, so now that parts of code are explicitly unfolded in
order to help compilers out.
This makes speed loss much less drastic on my laptop. That's probably as good
as we can do with MSVC without investing infinite amount of time looking trying
to workaround the optimizer.
Originally we thought it's needed in order to distinguish builtin file from
filename which starts with '@', but the filepath is actually full path there
and it's unlikely to have file system where '@' is a proper root character.
Surprisingly this does not give visible speed differences, but it's still
nice to get rid of redundant check.
There were two major problems with the interactivity of material previews:
- Beckmann tables were re-generated on every material tweak.
This is because preview scene is not set to be persistent, so re-triggering
the render leads to the full scene re-sync.
- Images could take rather noticeable time to load with OIIO from the disk
on every tweak.
This patch addressed this two issues in the following way:
- Beckmann tables are now static on CPU memory.
They're couple of hundred kilobytes only, so wouldn't expect this to be
an issue. And they're needed for almost every render anyway.
This actually also makes blackbody table to be static, but it's even smaller
than beckmann table.
Not totally happy with this approach, but others seems to complicate things
quite a bit with all this render engine life time and so..
- For preview rendering all images are considered to be built-in. This means
instead of OIIO which re-loads images on every re-render they're coming
from ImBuf cache which is fully manageable from blender side and unused
images gets freed later.
This would make it impossible to have mipmapping with OSL for now, but we'll
be working on that later anyway and don't think mipmaps are really so crucial
for the material preview.
This seems to be a better alternative to making preview scene persistent,
because of much optimal memory control from blender side.
Reviewers: brecht, juicyfruit, campbellbarton, dingto
Subscribers: eyecandy, venomgfx
Differential Revision: https://developer.blender.org/D1132
Official Documentation:
http://www.blender.org/manual/render/workflows/multiview.html
Implemented Features
====================
Builtin Stereo Camera
* Convergence Mode
* Interocular Distance
* Convergence Distance
* Pivot Mode
Viewport
* Cameras
* Plane
* Volume
Compositor
* View Switch Node
* Image Node Multi-View OpenEXR support
Sequencer
* Image/Movie Strips 'Use Multiview'
UV/Image Editor
* Option to see Multi-View images in Stereo-3D or its individual images
* Save/Open Multi-View (OpenEXR, Stereo3D, individual views) images
I/O
* Save/Open Multi-View (OpenEXR, Stereo3D, individual views) images
Scene Render Views
* Ability to have an arbitrary number of views in the scene
Missing Bits
============
First rule of Multi-View bug report: If something is not working as it should *when Views is off* this is a severe bug, do mention this in the report.
Second rule is, if something works *when Views is off* but doesn't (or crashes) when *Views is on*, this is a important bug. Do mention this in the report.
Everything else is likely small todos, and may wait until we are sure none of the above is happening.
Apart from that there are those known issues:
* Compositor Image Node poorly working for Multi-View OpenEXR
(this was working prefectly before the 'Use Multi-View' functionality)
* Selecting camera from Multi-View when looking from camera is problematic
* Animation Playback (ctrl+F11) doesn't support stereo formats
* Wrong filepath when trying to play back animated scene
* Viewport Rendering doesn't support Multi-View
* Overscan Rendering
* Fullscreen display modes need to warn the user
* Object copy should be aware of views suffix
Acknowledgments
===============
* Francesco Siddi for the help with the original feature specs and design
* Brecht Van Lommel for the original review of the code and design early on
* Blender Foundation for the Development Fund to support the project wrap up
Final patch reviewers:
* Antony Riakiotakis (psy-fi)
* Campbell Barton (ideasman42)
* Julian Eisel (Severin)
* Sergey Sharybin (nazgul)
* Thomas Dinged (dingto)
Code contributors of the original branch in github:
* Alexey Akishin
* Gabriel Caraballo
It is still possible to free a bit more memory by detecting buildin images
which are not used by shaders, but that's not going to improve memory usage
that much to bother about this now.
Such change brings peak memory usage from 4.1GB to 3.4GB when rendering
01_01_01_D layout scene from the Gooseberry project. Mainly because of
freeing memory used by rather huge environment map in the viewport.
Reviewers: campbellbarton, juicyfruit
Subscribers: eyecandy
Differential Revision: https://developer.blender.org/D1215
This attribute is not really supported for volumes, so it get's converted to
constant 0 at shader compile time.
TODO: We should consider doing the same for tangent attribute in order to save
some annoying checks at tracing time.
Our own implementation is in fact the same performance as in fast_math from
OpenShadingLanguage, but implementation from fast_math is using explicit madd
function, which increases chance of compiler deciding to use intrinsics.
This patch is based on some work done in D788 and re-formulation from Beckmann
implementation in OpenShadingLanguage.
Skipping texture lookup helps a lot on GPUs where it's more expensive to access
texture memory than to do some extra calculation in threads.
CPU code still uses lookup-table based approach since this seems to be still
faster (at least on computers i've got access to).
This change gives about 2% speedup on BMW scene with GTX560TI.
It did not preserve stratification too well and lookup-table approach was
working much better. There are now also some more interesting forumlation
from Wenzel and OpenShadingLanguage which should work better than old code.
This argument was unused and got nicely optimized out. But once it
starts to be using registers are getting stressed really crazy,
causing slow down of render.
It's not that bad because this typo could only caused not really
efficient BVH traversal, causing higher render times. Not as if
it was causing render artifacts.
It was an issue with what bounds to use for BVH node during construction.
Also corrected case when there are all 4 primitive types in the range and
also there're objects in the same range.
This inconsistency drove me totally crazy, it's really confusing
when it's inconsistent especially when you work on both Cycles and
Blender sides.
Shouldn;t cause merge PITA, it's whitespace changes only, Git should
be able to merge it nicely.
Issue was caused by accident in c8a9a56 which not only disabled glossy
reflection if Glossy visibility is disabled, but also Diffuse reflection.
Quite safe and should go to final release branch.
Issue was caused by cycles in shader graph confusing it's
simplification stage. Now we're ignoring links which are
marked as invalid from blender side so we don't run into
such cycles and keep graph code simple.
Issue was introduced in 01ee21f where i didn't notice *_setup()
function only doing partial initialization, and some of parameters
are expected to be initialized by callee function.
This was hitting only some setups, so tests with benchmark scenes
didn't unleash issues. Now it should all be fine.
This is to go to the 2.74 branch and we actually might re-AHOY.
Fix T44007: Cycles Volumetrics: block artifacts with overlapping volumes
The issue was caused by uninitialized parameters of some closures, which
lead to unpredictable behavior of shader_merge_closures().