Most of the time, Lamps in Cycles are just a constant emission closure, no texturing etc. Therefore, running a full shader evaluation is wasteful.
To avoid that, Cycles now detects these constant emission shaders and stores their value in the lamp data along with a flag in the shader.
Then, at runtime, if this flag is set, the lamp code just uses this value and only runs the full shader evaluation if it is neccessary.
In scenes with a lot of lamps and with "Sample all direct/indirect" enabled, this saves up to 20% of rendering time in my tests.
Reviewers: #cycles
Differential Revision: https://developer.blender.org/D2193
Storing multiple copies of a shader was needed when the displacement method was
a mesh option and could be different for each mesh. Now that its a shader option
this is unnecessary.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D2156
Displacement is now a per material setting, which means old files will have to
be updated if they had used displacement. Cool side effect of this change is
material previews now show displacement.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D2140
We don't have vectors re-allocation happening multiple times from inside
a loop anymore, so we can safely switch to a memory guarded allocator for
vectors and keep track on the memory usage at various stages of rendering.
Additionally, when building from inside Blender repository, Cycles will
use Blender's guarded allocator, so actual memory usage will be displayed
in the Space Info header.
There are couple of tricky aspects of the patch:
- TaskScheduler::exit() now explicitly frees memory used by `threads`.
This is needed because `threads` is a static member which destructor
isn't getting called on Blender's exit which caused memory leak print
to happen.
This shouldn't give any measurable speed issues, reallocation of that
vector is only one of fewzillion other allocations happening during
synchronization.
- Use regular guarded malloc (not aligned one). No idea why it was
made to be aligned in the first place. Perhaps some corner case tests
or so. Vector was never expected to be aligned anyway. Let's see if
we'll have actual bugs with this.
Reviewers: dingto, lukasstockner97, juicyfruit, brecht
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D1774
Basically the idea is to make code robust against extending
enum options in the future by falling back to a known safe
default setting when RNA is set to something unknown.
While this approach solves the issues similar to T47377,
but it wouldn't really help when/if any of the RNA values
gets ever deprecated and removed. There'll be no simple
solution to that apart from defining explicit mapping from
RNA value to Cycles one.
Another part which isn't so great actually is that we now
have to have some enum guards and give some explicit values
to the enum items, but we can live with that perhaps.
Reviewers: dingto, juicyfruit, lukasstockner97, brecht
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D1785
The title says it all actually, the idea is to make Cycles
only requiring Boost via 3rd party dependencies like OIIO
and OSL.
So now there are only few places which still uses Boost:
- Foreach, function bindings and threading primitives.
Those we can easily get rid with C++11 bump (which seems
inevitable sooner or later if we'll want ot use newer
LLVM for OSL),
- Networking devices
There's no quick solution for those currently, but there
are some patches around which improves serialization.
Reviewers: juicyfruit, mont29, campbellbarton, brecht, dingto
Reviewed By: brecht, dingto
Differential Revision: https://developer.blender.org/D1764
When World MIS is enabled by the user, we now check if we actually need it.
In case of a simple node setup (no procedurals, no HDRs..) we auto disable MIS internally to save render time.
This change is important for upcoming default changes.
Basically we can not use sharp closure as a substitude when filter glossy is
used. This is because we can not blur sharp reflection/refraction.
This is quite quick and not really clean implementation. Not really happy
with manual handling of original settings, but this is as good as we can do
in the quick patch. It's a good acknowledgment and we now can re-consider
some aspects of graph simplification to make such cases more natively
supported.
P.S. This failure would have been shown by our regression tests, so please,
bother a bit to run Cycles's test sweep before doing such optimizations.
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
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
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 commit makes it so blackbody and beckmann lookup tables are stored on CPU
after being generated and then only being copied to the device if needed.
This solves lag of viewport update when tweaking shader tree by using 266KB of
CPU memory.
Forbid OSL from polluting current conext with obscure stuff from
windows.h, it's not useful and unhealthy anyway.
Maybe we sohuld also forbid using abbreviated Glog constants as
well tho.
It is per-material setting which could be found under the Volume settings
in the material and world context buttons.
There could still be some code-wise improvements, like using variable-size
macro for interp3d instead of having interp3d_ex to which you can pass the
interpolation method.
It turns out that the new Beckmann sampling function doesn't work well with
Quasi Monte Carlo sampling, mainly near normal incidence where it can be worse
than the previous sampler. In the new sampler the random number pattern gets
split in two, warped and overlapped, which hurts the stratification, see the
visualization in the differential revision.
Now we use a precomputed table, which is much better behaved. GGX does not seem
to benefit from using a precomputed table.
Disadvantage is that this table adds 1MB of memory usage and 0.03s startup time
to every render (on my quad core CPU).
Differential Revision: https://developer.blender.org/D614
This gives you "Multiple Importance", "Distance" and "Equiangular" choices.
What multiple importance sampling does is make things more robust to certain
types of noise at the cost of a bit more noise in cases where the individual
strategies are always better.
So if you've got a pretty dense volume that's lit from far away then distance
sampling is usually more efficient. If you've got a light inside or near the
volume then equiangular sampling is better. If you have a combination of both,
then the multiple importance sampling will be better.
In practice this means that if you don't connect a texture to your volume nodes
it will figure that out and render the node faster, rather than you having to
specify it manually.
Main weakness is custom OSL nodes where we have to assume it is heterogeneous
because we don't know what kind of data the node accesses.
Volumes can now have textured colors and density. There is a Volume Sampling
panel in the Render properties with these settings:
* Step size: distance between volume shader samples when rendering the volume.
Lower values give more accurate and detailed results but also increased render
time.
* Max steps: maximum number of steps through the volume before giving up, to
protect from extremely long render times with big objects or small step sizes.
This is much more compute intensive than homogeneous volume, so when you are not
using a texture you should enable the Homogeneous Volume option in the material
or world for faster rendering.
One important missing feature is that Generated texture coordinates are not yet
working in volumes, and they are the default coordinates for nearly all texture
nodes. So until that works you need to plug in object texture coordinates or a
world space position.
This is work by "storm", Stuart Broadfoot, Thomas Dinges and myself.
New features:
* Bump mapping now works with SSS
* Texture Blur factor for SSS, see the documentation for details:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/Shaders#Subsurface_Scattering
Work in progress for feedback:
Initial implementation of the "BSSRDF Importance Sampling" paper, which uses
a different importance sampling method. It gives better quality results in
many ways, with the availability of both Cubic and Gaussian falloff functions,
but also tends to be more noisy when using the progressive integrator and does
not give great results with some geometry. It works quite well for the
non-progressive integrator and is often less noisy there.
This code may still change a lot, so unless you're testing it may be best to
stick to the Compatible falloff function.
Skin test render and file that takes advantage of the gaussian falloff:
http://www.pasteall.org/pic/show.php?id=57661http://www.pasteall.org/pic/show.php?id=57662http://www.pasteall.org/blend/23501
* Added a node to convert a temperature in Kelvin to an RGB color. This can be used e.g. for lights, to easily find the right color temperature.
= Some common temperatures =
Candle light: 1500 Kelvin
Sunset/Sunrise: 1850 Kelvin
Studio lamps: 3200 Kelvin
Horizon daylight: 5000 Kelvin
Documentation: http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/More#Blackbody
Thanks to Philipp Oeser (lichtwerk), who essentially contributed to this with a patch! :)
This is part of my GSoC 2013 project. SVN merge of r57424, r57487, r57507, r57525, r58253 and r58774
well as I would like, but it works, just add a subsurface scattering node and
you can use it like any other BSDF.
It is using fully raytraced sampling compatible with progressive rendering
and other more advanced rendering algorithms we might used in the future, and
it uses no extra memory so it's suitable for complex scenes.
Disadvantage is that it can be quite noisy and slow. Two limitations that will
be solved are that it does not work with bump mapping yet, and that the falloff
function used is a simple cubic function, it's not using the real BSSRDF
falloff function yet.
The node has a color input, along with a scattering radius for each RGB color
channel along with an overall scale factor for the radii.
There is also no GPU support yet, will test if I can get that working later.
Node Documentation:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/Shaders#BSSRDF
Implementation notes:
http://wiki.blender.org/index.php/Dev:2.6/Source/Render/Cycles/Subsurface_Scattering
operator< had wrong brackets, changed it now to be more clear.
Fix#33404: crash GPU rendering with OSL option still enabled. There was a check
to disable OSL in this case, but it shouldn't have modified scene->params because
this is used for comparison in scene->modified().
Documentation here:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/OSLhttp://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.65/Cycles
These changes require an OSL build from this repository:
https://github.com/DingTo/OpenShadingLanguage
The lib/ OSL has not been updated yet, so you might want to keep OSL disabled
until that is done.
Still todo:
* Auto update for external .osl files not working currently, press update manually
* Node could indicate better when a refresh is needed
* Attributes like UV or generated coordinates may be missing when requested from
an OSL shader, need a way to request them to be loaded by cycles
* Expose string, enum and other non-socket parameters
* Scons build support
Thanks to Thomas, Lukas and Dalai for the implementation.
Most of the changes are related to adding support for motion data throughout
the code. There's some code for actual camera/object motion blur raytracing
but it's unfinished (it badly slows down the raytracing kernel even when the
option is turned off), so that code it disabled still.
Motion vector export from Blender tries to avoid computing derived meshes
when the mesh does not have a deforming modifier, and it also won't store
motion vectors for every vertex if only the object or camera is moving.
Currently supported passes:
* Combined, Z, Normal, Object Index, Material Index, Emission, Environment,
Diffuse/Glossy/Transmission x Direct/Indirect/Color
Not supported yet:
* UV, Vector, Mist
Only enabled for CPU devices at the moment, will do GPU tweaks tommorrow,
also for environment importance sampling.
Documentation:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Passes
decided it's better to render objects as either surface or volume.
This may break the volume rendering patch, but shaders with volume closures still
get tagged as having volume closures, so it should be fixable without too many
changes.
