Previously RGB Curves node will clamp input to 0..1 which is rather useless
when one wants to use HDR image textures and do bit of correction on them.
Now kernel code supports extrapolation of baked LUT based on first/last two
table points and performs linear extrapolation.
The only tricky part is to guess the range to bake the LUT for. Currently
it's using simple approach -- minmax of the input curves. While this behaves
ok for the simple cases it's easy to trick the system up causing incorrect
results.
Not sure we can solve those issues in a general case and since the new code
is giving more expected results it's not that bad actually. In the worst
case artist migh always create explicit point to make sure LUT is created
for the needed HDR range.
Reviewers: brecht, juicyfruit
Subscribers: sebastian_k
Differential Revision: https://developer.blender.org/D1658
The issue was caused by non-continuous tangent space calculated for triangles.
This commit adds a Tangent input to Hair BSDF node which can be used to hook up
Tangent calculated form UV as an input to the node in order to make sure the
tangent space is continuous.
Doing this as an input instead of using default tangent layer from UV because of
several reasons:
- This way it's really easy to preserve compatibility with existing setups.
- Default UV map is not necessarily giving continuous space, one might want to
use other tangent space sources or distort the space for some artistic
decision.
Reviewers: juicyfruit, dingto
Reviewed By: dingto
Differential Revision: https://developer.blender.org/D1428
Added some extra seed to the hash, so it's now less likely to give repetitive
patters at values around zero.
This will change distribution of bricks for existing files. but it's something
inevitable.
* Did not check data2, this partially fixes T45583.
* Initialize data2 in some closures to avoid potential problems.
Differential Revision: https://developer.blender.org/D1436
The idea of this node is to sampling of 3D voxels at a given coordinate
supporting different mapping strategies (world space mapping, object
local space etc).
Currently not in use, it's a preparation step for supporting point density
textures.
Glass BSDF was doing some magic with copying weigths from initial closure
onto refraction one and the code was not checking properly for the number
of closures.
This will help figuring out cases when node was not properly handled by the SVM
by aborting execution on CPU, where all the nodes are expected to be supported.
This commits finishes initial selective nodes compilation into kernel, which
helps a lot performance-wise for AMD OpenCL kernels.
Split by node groups is based on statistics from simple scenes like BMW and
more complex scenes like mango and gooseberry production files. Further
tweaks are always possible, but it should be a good starting point.
TODO: Still need to ignore unused nodes when calculating requested shader
features.
Same as last commit, code is unused and this one actually would have required some fixes,
as these variants output values outside the 0-1 value range, which doesn't fit Cycles shader design.
Let's finally delete this code, after 4 years of being unused,
there really is no excuse anymore.
If we decide to extend the procedural textures in SVM, we can do this anytime in the future.
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
The goal is to be able to compile kernel with nodes which are actually needed
to render current scene, hence improving performance of the kernel,
The idea is:
- Have few node groups, starting with a group which contains nodes are used
really often, and then couple of groups which will be extension of this one.
- Have feature-based nodes disabling, so it's possible to disable nodes related
to features which are not used with the currently used nodes group.
This commit only lays down needed routines for this approach, actual split will
happen later after gathering statistics from bunch of production scenes.
Now we calculate color in range 800..12000 using an approximation a/x+bx+c for R and G and ((at + b)t + c)t + d) for B.
Max absolute error for RGB for non-lut function is less than 0.0001, which is enough to get the same 8 bit/channel color as for OSL with a noticeable performance difference.
However there is a slight visible difference between previous non-OSL implementation because of lookup table interpolation and offset-by-one mistake.
The previous implementation gave black color outside of soft range (t > 12000), now it gives the same color as for 12000.
Also blackbody node without input connected is being converted to value input at shader compile time.
Reviewers: dingto, sergey
Reviewed By: dingto
Subscribers: nutel, brecht, juicyfruit
Differential Revision: https://developer.blender.org/D1280
This more a workaround for CUDA optimizer which can't optimize clamp(x, 0, 1)
into a single instruction and uses 4 instructions instead.
Original patch by @lockal with own modification:
Don't make changes outside of the kernel. They don't make any difference
anyway and term saturate() has a bit different meaning outside of kernel.
This gives around 2% of speedup in Barcelona file, but in more complex shader
setups with lots of math nodes with clamping speedup could be much nicer.
Subscribers: dingto
Projects: #cycles
Differential Revision: https://developer.blender.org/D1224
This way we can get rid of inefficient memory usage caused by BVH boundbox
part being unused by leaf nodes but still being allocated for them. Doing
such split allows to save 6 of float4 values for QBVH per leaf node and 3
of float4 values for regular BVH per leaf node.
This translates into following memory save using 01.01.01.G rendered
without hair:
Device memory size Device memory peak Global memory peak
Before the patch: 4957 5051 7668
With the patch: 4467 4562 7332
The measurements are done against current master. Still need to run speed tests
and it's hard to predict if it's faster or not: on the one hand leaf nodes are
now much more coherent in cache, on the other hand they're not so much coherent
with regular nodes anymore.
Reviewers: brecht, juicyfruit
Subscribers: venomgfx, eyecandy
Differential Revision: https://developer.blender.org/D1236
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 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.
This attribute missed derivatives calculation.
Not totally sure what's the proper approach for algebraic derivative
calculation, so calculating them by definition. This isn't fastest
way to do it in this case and could be replaced with some smarter magic
in the wireframe calculation loop.
At least currently implemented approach is better than nothing.
OpenCL doesn't let you to get address of vector components, which
is kinda annoying. On the other hand, maybe now compiler will have
more chances to optimize something out.
Hair BSDF did not have proper behavior because of non-normalized
tangent direction (which it expected to be normalized).This lead
to wrong labels being returned by the hair BSDF samplers.
This is the same as blender internal's texture mapping from another object,
so this way it's possible to control texture space of one object by another.
Quite straightforward change apart from the workaround for the stupidness of
the dependency graph. Now shader has flag telling that it depends on object
transform. This is the simplest way to know which shaders needs to be tagged
for update when object changes. This might give some false-positive tags now
but reducing them should not be priority for Cycles and rather be a priority
to bring new dependency graph.
Also GLSL preview does not support using other object for mapping.
This is actually correct for BI shading as well and to be addressed as
a part of general GLSL viewport improvements since it's not really clear
how to support this in GLSL.
Reviewers: brecht, juicyfruit
Subscribers: eyecandy, venomgfx
Differential Revision: https://developer.blender.org/D1021
This way Cycles finally becomes feature-full on image projections
compared to Blender Internal and Gooseberry Project Team could
finally finish the movie.
This reverts commit 1549fea9995c348bc14a9105df5e460644e2b33a.
After some further discussion with other developers in the team it becomes
clear there's no correct solution here. It is just more matter of what's
more convenient in particular case.
We're just going back to old code to avoid possible frustration with the
older files in newer blenders. This also means all HSV/HSL is considered
to be "linear" in the shading nodes.
Would be ported to 2.73 final.
These nodes were assuming sRGB input/output which is for sure wrong for the
shader pipeline which works in the linear space.
So now conversion to/from linear space happens in these nodes which makes them
making sence in the shader context but which might change look and feel of
existing scenes.
This mainly happens when over-saturating already saturated color.
After some discussion with Campbell and loads of tests we decided
to clamp the result RGB color. As an alternative we might want to
clamp corrected HSV values instead, but that would lead to some
larger changes in the render results.
TODO: The same is to be done for compositor nodes.
After discussion with cambo here we decided it's better to choose arbitrary side of the box
(in this case it's X-axis) and use image from it. That's better than doing a blackness.
P.S. This is literally a corner case anyway.
Was hooked up last year for testing purposes, as we already had some code for it, but the closure itself is not really good nor really useful, so let's remove it.
