This PR enables strip curve drawing when performing the workbench
rendertests. On Intel/vulkan the lines are to far off. Using strip will
reduce platform differences. Downside is that (basic) line rendering is not
covered anymore by a render test.
Pull Request: https://projects.blender.org/blender/blender/pulls/146820
On its own, the main functionality of the Radial Tiling node
is the ability to divide a 2D Cartesian coordinate system into
as many radial segments as specified by the "Segments" input.
Each segment has its own affinely transformed coordinate system,
provided through the "Segment Coordinates" output, which can be
used to tile textures in a radially symmetric manner.
Additionally, a unique index is provided for every segment through
the "Segment ID" output, the width of each segment at Y-coordinate
of the "Segment Coordinates" output without normalization = 0 is
provided through the "Segment Width" output and the rotation value
of the affine transformation of the coordinate system of each segment
is provided through the "Segment Rotation" output.
The roundness of the coordinate lines of the "Segment Coordinates"
output can be controlled through the "Roundness" inputs.
This can be used to make the coordinate systems of the segments
a mix of Cartesian and polar coordinates.
Lastly, the lines of points of the "Segment Coordinates" output with
constant Y-coordinates have the shape of polygon with rounded corners,
which can be used to procedurally create rounded polygons.
Pull Request: https://projects.blender.org/blender/blender/pulls/127711
Implementation of the design task #142969.
This adds the following:
- Exact GPU interpolation of curves of all types.
- Radius attribute support.
- Cyclic curve support.
- Resolution attribute support.
- New Cylinder hair shape type.
What changed:
- EEVEE doesn't compute random normals for strand hairs anymore. These are considered legacy now.
- EEVEE now have an internal shadow bias to avoid self shadowing on hair.
- Workbench Curves Strip display option is no longer flat and has better shading.
- Legacy Hair particle system evaluates radius at control points before applying additional subdivision. This now matches Cycles.
- Color Attribute Node without a name do not fetch the active color attribute anymore. This now matches Cycles.
Notes:
- This is not 100% matching the CPU implementation for interpolation (see the epsilons in the tests).
- Legacy Hair Particle points is now stored in local space after interpolation.
The new cylinder shape allows for more correct hair shading in workbench and better intersection in EEVEE.
| | Strand | Strip | Cylinder |
| ---- | --- | --- | --- |
| Main |  |  | N/A |
| PR |  |  |  |
| | Strand | Strip | Cylinder |
| ---- | --- | --- | --- |
| Main |  | | N/A |
| PR | ||  |
Cyclic Curve, Mixed curve type, and proper radius support:
Test file for attribute lookup: [test_attribute_lookup.blend](/attachments/1d54dd06-379b-4480-a1c5-96adc1953f77)
Follow Up Tasks:
- Correct full tube segments orientation based on tangent and normal attributes
- Correct V resolution property per object
- More attribute type support (currently only color)
TODO:
- [x] Attribute Loading Changes
- [x] Generic Attributes
- [x] Length Attribute
- [x] Intercept Attribute
- [x] Original Coordinate Attribute
- [x] Cyclic Curves
- [x] Legacy Hair Particle conversion
- [x] Attribute Loading
- [x] Additional Subdivision
- [x] Move some function to generic headers (VertBuf, OffsetIndices)
- [x] Fix default UV/Color attribute assignment
Pull Request: https://projects.blender.org/blender/blender/pulls/143180
Previously, we used precomputed Gaussian fits to the XYZ CMFs, performed
the spectral integration in that space, and then converted the result
to the RGB working space.
That worked because we're only supporting dielectric base layers for
the thin film code, so the inputs to the spectral integration
(reflectivity and phase) are both constant w.r.t. wavelength.
However, this will no longer work for conductive base layers.
We could handle reflectivity by converting to XYZ, but that won't work
for phase since its effect on the output is nonlinear.
Therefore, it's time to do this properly by performing the spectral
integration directly in the RGB primaries. To do this, we need to:
- Compute the RGB CMFs from the XYZ CMFs and XYZ-to-RGB matrix
- Resample the RGB CMFs to be parametrized by frequency instead of wavelength
- Compute the FFT of the CMFs
- Store it as a LUT to be used by the kernel code
However, there's two optimizations we can make:
- Both the resampling and the FFT are linear operations, as is the
XYZ-to-RGB conversion. Therefore, we can resample and Fourier-transform
the XYZ CMFs once, store the result in a precomputed table, and then just
multiply the entries by the XYZ-to-RGB matrix at runtime.
- I've included the Python script used to compute the table under
`intern/cycles/doc/precompute`.
- The reference implementation by the paper authors [1] simply stores the
real and imaginary parts in the LUT, and then computes
`cos(shift)*real + sin(shift)*imag`. However, the real and imaginary parts
are oscillating, so the LUT with linear interpolation is not particularly
good at representing them. Instead, we can convert the table to
Magnitude/Phase representation, which is much smoother, and do
`mag * cos(phase - shift)` in the kernel.
- Phase needs to be unwrapped to handle the interpolation decently,
but that's easy.
- This requires an extra trig operation in the kernel in the dielectric case,
but for the conductive case we'll actually save three.
Rendered output is mostly the same, just slightly different because we're
no longer using the Gaussian approximation.
[1] "A Practical Extension to Microfacet Theory for the Modeling of
Varying Iridescence" by Laurent Belcour and Pascal Barla,
https://belcour.github.io/blog/research/publication/2017/05/01/brdf-thin-film.html
Pull Request: https://projects.blender.org/blender/blender/pulls/140944
This commit adds a test for the situation in which a AOV pass is used
on a object with a fully or semi-transparent material, either using the
transparent BSDF directly, or mixing it with some other material.
Pull Request: https://projects.blender.org/blender/blender/pulls/141068
This changes the engine identifier back to `BLENDER_EEVEE`.
We keep the `BLENDER_EEVEE_NEXT` identifier around for
versioning reasons (have to detect when it is the active
engine of a older file).
This also rename a bunch of pannels that were using `next`
in their name.
This is a breaking change for Addons compatibility.
Pull Request: https://projects.blender.org/blender/blender/pulls/140282
This change moves the tests data files and publish folder of assets
repository to the main blender.git repository as LFS files.
The goal of this change is to eliminate toil of modifying tests,
cherry-picking changes to LFS branches, adding tests as part of a
PR which brings new features or fixes.
More detailed explanation and conversation can be found in the
design task.
Ref #137215
Pull Request: https://projects.blender.org/blender/blender/pulls/137219
