This commit adds the `light:random` attribute to OSL, allowing the
object info node to now match between SVM and OSL when using the
random output on a light.
Pull Request: https://projects.blender.org/blender/blender/pulls/134095
The derivatives of the normal were simply not computed.
The offsetted normals are computed by perturbating the barycentric
coordinates. At triangle boundaries, the normals are extrapolated,
so discontinuities might be visible.
Currently only supported on triangles.
Pull Request: https://projects.blender.org/blender/blender/pulls/133769
Use sub-pixel differentials for bump mapping helps with reducing
artifacts when objects are moving or when textures have high frequency
details.
Currently we scale it by 0.1 because it seems to work good in practice,
we can adjust the value in the future if it turns out to be impractical.
Ref: #122892
Pull Request: https://projects.blender.org/blender/blender/pulls/133991
That version has a bunch of API changes, so by dropping support for older
versions we can remove old compatibility code.
Also, that version is required for OptiX support, so building a fully-featured
Cycles wasn't possible with older OSL anyways.
Pull Request: https://projects.blender.org/blender/blender/pulls/133746
OSL has OSL::ShaderGlobals, which contains all the state for OSL shader
execution. The renderer fills it out and hands a pointer to OSL, and any
callbacks (e.g. for querying attributes) get the pointer back.
In order to store renderer-specific data in it, there's a few opaque pointers
in the struct, but using those has led to a mess of reinterpret_cast<> and
pointer indirection in order to carry all the data around.
However, there is a way to do this nicer: Good old C-style struct inheritance.
In short: Unless you're doing pointer arithmetic, you can just add additional
data at the end of a base struct, and the rest of the code won't care.
In this case, this means that we can have our own ShaderGlobals struct and
add more Cycles-specific data at the end. Additionally, we can replace the
generic opaque void pointers with ones of the correct type, which saves us
from needing to cast them back.
Since we have a copy of ShaderGlobals for GPU OSL anyways, it's just a matter
of refactoring the code a bit to make use of that.
The advantages of this are:
- Avoids casts all over the place, just needs one cast to turn our
ShaderGlobals into the "base" type that OSL expects and one to turn the
pointer that OSL gives us on callbacks back into our "derived" type.
- Removes indirection, all the relevant stuff (sd, kg, state) is now
directly in the ShaderGlobals
- Removes some OSL-specific state from ShaderData, which helps to keep
memory usage down
Pull Request: https://projects.blender.org/blender/blender/pulls/133689
The oren_nayar_diffuse_bsdf closure in OSL had two issues:
- It broke when used with roughness of zero
- It only used the provided albedo for energy compensation, so it still
required the user to multiply with the albedo
Therefore, this handles the zero roughness corner case and includes
the albedo in the closure weight.
This makes no difference when using the closure through the Diffuse
or Principled BSDF nodes, only for custom OSL shaders.
Pull Request: https://projects.blender.org/blender/blender/pulls/133597
The `ZDepth` output of the camera data node was different between SVM
and OSL.
SVM would output the `ZDepth`, with negative distances for points
behind the camera. While OSL would output the absolute of the distance,
which resulted in points behind the camera becoming positive.
Align OSL to SVM and allow outputting the negative distance as it
allows users to differentiate between what's in front or behind the
camera.
Pull Request: https://projects.blender.org/blender/blender/pulls/132837
Check was misc-const-correctness, combined with readability-isolate-declaration
as suggested by the docs.
Temporarily clang-format "QualifierAlignment: Left" was used to get consistency
with the prevailing order of keywords.
Pull Request: https://projects.blender.org/blender/blender/pulls/132361
* Use .empty() and .data()
* Use nullptr instead of 0
* No else after return
* Simple class member initialization
* Add override for virtual methods
* Include C++ instead of C headers
* Remove some unused includes
* Use default constructors
* Always use braces
* Consistent names in definition and declaration
* Change typedef to using
Pull Request: https://projects.blender.org/blender/blender/pulls/132361
The Texture Coordinate node has a "Object" output that can be
derived from the object being sampled, or a reference object.
With Cycles OSL, the "Object" output of the Texture Coordinate
would not use the reference object if one was active, and the
node was used on a world shader.
This commit fixes this issue.
Pull Request: https://projects.blender.org/blender/blender/pulls/132515
The output normals of the Texture Coordinate node when using the OSL
backend were not normalized, leading to incorrect values in
some situations.
This commit fixes this issue by normalizing the normals in this situation.
Pull Request: https://projects.blender.org/blender/blender/pulls/132514
Previous implemenation of 5 < d < 50 was taken from the main paper,
fitting for smaller sizes are found in the supplemental. They are less
forward-scattering.
Pull Request: https://projects.blender.org/blender/blender/pulls/130234
Based on #123377 by @brecht, but Gitea doesn't like the rebase these
so here's a new PR.
The purpose here is to switch to fused OptiX programs for OSL execution
on CUDA. On the one hand, this makes the code easier since, but there's
also another advantage - how memory allocation is managed.
OSL shaders need memory to store intermediate values, but how much is
needed depends on the complexity of the shader. With the split program
approach, Cycles had to provide that memory, so we had to allocate a
certain amount (2 KiB, to be precise) statically and show an error if
the shader would need more. If the shader used less (which is the case
for the vast majority), the memory was just wasted.
By switching to fused kernels, OSL knows the required amount during JIT
codegen, so it can allocate only what's required, which avoids this
waste. One still needs to set a maximum, and in theory, OSL would also
support spilling over into a Cycles-provided alternative memory region.
However, we currently don't implement that - instead, we default to the
same 2048 limit as before and let advanced users override it via the
CYCLES_OSL_GROUPDATA_ALLOC environment variable if really needed.
Co-authored-by: Brecht Van Lommel <brecht@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/130149
All the OSL matrix functions had been implemented using the
`Transform` utility of Cycles, but that's built around a 4x3 matrix,
when the OSL matrix functions are working with 4x4 matrices.
This resulted in them not producing results consistent with the
CPU implementation.
This fixes that by making use of the `ProjectionTransform` utility
of Cycles instead, because it's built around a 4x4 matrix. Since
matrix inversion is required, I had to make a few more utility
functions available on the GPU (except Metal, due to use of
references/pointers without specification) that were previously
CPU-only.
Co-authored-by: Brecht Van Lommel <brecht@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/110102
The `osl_wavelength_color_vf` intrinsic was missing an implementation for
OptiX, causing a link error when attempting to load OSL shaders using the
wavelength node.
Pull Request: https://projects.blender.org/blender/blender/pulls/129372
Previously, Cycles only supported the Henyey-Greenstein phase function for volume scattering.
While HG is flexible and works for a wide range of effects, sometimes a more physically accurate
phase function may be needed for realism.
Therefore, this adds three new phase functions to the code:
Rayleigh: For particles with a size below the wavelength of light, mostly athmospheric scattering.
Fournier-Forand: For realistic underwater scattering.
Draine: Fairly specific on its own (mostly for interstellar dust), but useful for the next entry.
Mie: Approximates Mie scattering in water droplets using a mix of Draine and HG phase functions.
These phase functions can be combined using Mix nodes as usual.
Co-authored-by: Lukas Stockner <lukas@lukasstockner.de>
Pull Request: https://projects.blender.org/blender/blender/pulls/123532
Add Metallic BSDF Node to the shader editor.
This node can primarily be used to create more realistic looking
metallic materials than the existing Glossy BSDF node.
This commit does not add any new closures to Cycles, it simply exposes
existing closures that were previous hard to access on their own.
- Exposes the F82 fresnel type that is currently used by the
metallic component of the Principled BSDF. Results should match
between the Metallic BSDF and Principled BSDF when using the same
settings.
- Exposes the Physical Conductor fresnel type that was previously
limited to custom OSL scripts. The Conductor fresnel type accepts
IOR and Extinction coefficients to define the appearance of the
material based off real life measurements.
EEVEE only supports the F82 fresnel type with internal code to convert
the the physical conductor inputs in to a colour format for F82,
which can lead to noticeable rendering differences with
some configurations.
Pull Request: https://projects.blender.org/blender/blender/pulls/114958
This patch improves the isotropic Gabor noise UI controls such that
variations happen in both directions of the base orientation, as opposed
to being biased in the positive direction only.
Thanks to Charlie Jolly for suggesting this improvement.
This patch optimizes the Gabor noise standard deviation estimation by
computing the upper limit of the integral as the frequency approaches
infinity, since the integral is mostly constant for the relevant
frequency range. The limits are 0.25 for the 2D case and 1 / 4 * sqrt2
for the 3D case.
This also improves normalization for low frequencies, possibly due to
the effect of windowing.
Thanks to Charlie Jolly for spotting the optimization.
