Previously, the Principled BSDF used the Subsurface input to scale the radius.
When it was zero, it used a diffuse closure, otherwise a subsurface closure.
This sort of scaling input makes sense, but it should be specified in distance
units, rather than a 0..1 factor, so this commit changes the unit and renames
the input to Subsurface Scale.
Additionally, it adds support for mixing diffuse and subsurface components.
This is part of e.g. the OpenPBR spec, and the logic behind it is to support
modeling e.g. dirt or paint on top of skin. Before, materials would be either
fully diffuse (radius=0) or fully subsurface.
For typical materials, this mixing factor will be either zero or one
(just like metallic or transmission), but supporting fractional inputs makes
sense for e.g. smooth transitions at boundaries.
Another change is that there is no separate Subsurface Color anymore - before,
this was mixed with the Base Color using the Subsurface input as the factor,
but this was not really useful since that input was generally very small.
And finally, the handling of how the path enters the material for random walk
subsurface scattering is changed. Before, this always used lambertian (diffuse)
transmission, but this caused some problems, like overly white edges.
Instead, two different methods are now used, depending on the selected mode.
In Fixed Radius mode, the code assumes a simple medium boundary, and performs
refraction into the material using the main Roughness and IOR inputs.
Meanwhile, when not using Fixed Radius, the code assumes a more complex
boundary (as typically found on organic materials, e.g. skin), so the entry
bounce has a 50/50 chance of being either diffuse transmission or refraction
using the separate Subsurface IOR input and a fixed roughness of 1.
Credit for this method goes to Christophe Hery.
Pull Request: https://projects.blender.org/blender/blender/pulls/110989
- Adds tint control, which simulates volumetric absorption inside the coating.
This results in angle-dependent saturation and affects all underlying layers
(diffuse, subsurface, metallic, transmission). It provides a physically-based
alternative to ad-hoc effects such as tinted specular highlights.
- Renames the component from "Clearcoat" to "Coat", since it's no longer
necessarily clear now. This matches naming in e.g. other renderers or OpenPBR.
- Adds an explicit Coat IOR input, in preparation for future smarter IOR logic
around the interaction between Coat and main IOR. This used to be hardcoded
to 1.5.
- Removes hardcoded 0.25 weight multiplier, and adds versioning code to update
existing files accordingly. OBJ import/export still applies the factor.
- Replaces the GTR1 microfacet component with regular GGX. This removes a corner
case in the Microfacet code, solves #53038, and makes us more consistent with
other standard surface shaders. The original Disney BSDF used GTR1, but it
doesn't appear that it caught on in the industry.
Co-authored-by: Weizhen Huang <weizhen@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/110993
5cf7089e43 added the `BuiltinBits::LAYER` to shaders with a geometry
stage. This causes compilation errors when
`GLContext::layered_rendering_support` is false (otherwise the flag
does nothing).
This PR moves the `LAYER` flags to the `no_geom` shader versions and
adds a check to `ShaderCreateInfo::finalize()` to ensure the `LAYER` flag
is not used in shaders with a geometry stage.
Pull Request: https://projects.blender.org/blender/blender/pulls/112245
Component swizzling is part of an image view and localized in the code.
With component swizzling a different channel (or 0 or 1) can be read
when the component is accessed.
Pull Request: https://projects.blender.org/blender/blender/pulls/112273
Adding support for Texture View in Vulkan backend.
When a VKTexture is a texture view many options become
irrelevant, but isn't actually clear via its API. Added
asserts to make sure that the usage is supported.
This patch allows rendering simple workbench-next scenes
without any validation errors.
Pull Request: https://projects.blender.org/blender/blender/pulls/110887
When `COMP_U*` is used together with a `GPU_FETCH_INT` the backend
tried to convert them to floats. What is of course not what should
happen.
Issue was that these cases were never correctly tested. With this
change the `data` attribute of the `overlay_edit_mesh` shaders are
transferred correctly and can draw some pixels as intended.
Pull Request: https://projects.blender.org/blender/blender/pulls/112270
Shader draw parameter support is needed for Workbench-next. (Almost) All
devices that we support also supports shader draw parameters. This PR
doesn't include a workaround for devices that don't have support.
For end-users this PR will allow workbench-next to render the object on
the correct location. Before this patch they were always drawn on the origin.
The catch is that OpenGL uses gl_InstanceID which always starts counting at 0.
Vulkan has gl_InstanceIndex which holds the correct instance number. By
subtracting the gl_InstanceIndex from gl_BaseInstance will get the correct
gl_InstanceID.
This patch also activates some device extensions to perform in shader printf
statements inside a shader. Documentation for this will be added to the dev
docs how to use them.
Pull Request: https://projects.blender.org/blender/blender/pulls/111461
Schlick's approaximation used by EEVEE is not accurate near `IOR == 1`,
especially when IOR is exactly one, there is no specular reflection and
the material should appear diffuse.
Cycles bypass the issue by lerping between the f0 and f90 color using
the factor derived from real Fresnel curve. In EEVEE we can use the same
trick as in Glass BSDF to smooth the transition at `IOR == 1`.
Note that at `IOR < 1` there is still mismatch, because f0 is prebaked
in the BTDF look up table. In the future if we color f0 using
`specular_tint`, we can split the table and use the BTDF LUT for the
specular component too.
Enables performance optimizations and new rendering
features through allowing colour attachments to be
tagged with a rasterization order group. This means that
all accesses to the same pixel location are guaranteed
to happen in submission order.
This lays the ground work for tile-based architecture
optimizations, enabling additional features for
deferred rendering which allow subsequent passes
which operate on pixel data to occur in order, while
memory remains on-tile.
This patch allows fragment outputs to be tagged
with a raster order group and also adds a new
FragmentTileIn parameter to a shader, which allows
speciication of incoming parameters from a previous
draw.
Authored by Apple: Michael Parkin-White
Pull Request: https://projects.blender.org/blender/blender/pulls/111748
Enhance custom framebuffer binding state to allow
specification of clear color as part of the loadstore
state at framebuffer bind time.
This ensures all parameters controlling attachment
loading and storage behaviour can be explicitly
specified when binding a framebuffer.
This change enables optimizations which leverage
explicit framebuffer load store state to also specify
a clear color without prematurely triggering a
clear which may occur independently to
render work when using GPU_framebuffer_clear(..).
Authored by Apple: Michael Parkin-White.
Pull Request: https://projects.blender.org/blender/blender/pulls/111810
Removes old unused bind state parameters from
prior to the addition of explicit resource location support.
Patch also ensures compute state is reset between each
encoder and adds a debug option to dispatch each
compute command within its own encoder for debugging
synchronization issues.
Authored by Apple: Michael Parkin-White
Pull Request: https://projects.blender.org/blender/blender/pulls/111753
Memoryless textures are only used as intermediate attachments
during rasterization, but do not have any backing storage. This is
particularly useful if a virutal framebuffer is needed, or, there is
a situation where a depth buffer is only needed within the pass
itself and the results are discarded once the pass completes.
Authored by Apple: Michael Parkin-White
Pull Request: https://projects.blender.org/blender/blender/pulls/111749
imageStoreFast provides a variant of imageStore which does
not perform any bounds checking, reducing shader divergence,
register pressure and increasing performance through fewer
instructions.
However, this should only be used for cases where the writing
coordinate is guaranteed to fall within the texture.
Authored by Apple: Michael Parkin-White
Pull Request: https://projects.blender.org/blender/blender/pulls/111750
Some shaders using gl_Layer/gpu_Layer were missing
the correct usage bit in the shader create info. Shaders
also need to inherit feature usage bits from included
additional_info.
Authored by Apple: Michael Parkin-White
Pull Request: https://projects.blender.org/blender/blender/pulls/111751
This ports the LUT using compute shader.
All LUT are computed by the same compute shader
to avoid boiler plate code to add new LUTs.
As for the generation code itself it is mostly the
same except for the use of `hammersley_2d` instead of
regular grid sampling. Regular grid did not improve
anything and was a bit more cumbersome.
This also bumps the number of samples very high
for more precision.
The new utility class for computing the LUT has
methods to write the content to a PFM image file
or as C++ array header.
The hash tables and vector blenlib headers were pulling many more
headers than they actually need, including the C base math header,
our C string API header, and the StringRef header. All of this
potentially slows down compilation and polutes autocomplete
with unrelated information.
Also remove the `ListBase` constructor for `Vector`. It wasn't used
much, and making it easy to use `ListBase` isn't worth it for the
same reasons mentioned above.
It turns out a lot of files depended on indirect includes of
`BLI_string.h` and `BLI_listbase.h`, so those are fixed here.
Pull Request: https://projects.blender.org/blender/blender/pulls/111801
changes include:
* Use microfacet normal instead of macronormal. Previously Cycles used
macronormal for Glass BSDF and Transmission component in Principeld
BSDF, leading to artefacts at grazing angles. This has been corrected
in 5f9b518a8b and 89218b66c2. Now change EEVEE to match this behaviour.
* GGX distribution is now darker due to the shadowing-masking term,
while Multiscatter GGX preserves energy. This now matches Cycles too.
Pull Request: https://projects.blender.org/blender/blender/pulls/111687
This is a rewrite of GHOST_ContextVK to align with Metal backend as described
in #111389 - solution 3 with the adaptation that GHOST is still responsible
for presenting the swap chain image and a post callback is still needed in
case the swapchain is recreated.
This PR also includes some smaller improvements in stability.
Technical documentation: https://developer.blender.org/docs/eevee_and_viewport/gpu/vulkan/swap_chain/
* Renderpasses and framebuffers are not owned anymore by GHOST_ContextVK
* VKFramebuffer doesn't contain a swap chain image.
* Swapchain images can only be used as a blit destination or present source.
Not as an attachment.
* GHOST_ContextVK::swapBuffers would call a callback with the image the
GPU module needs to blit the results to.
* Clearing of depth/stencil attachments when no depth write state is set.
* Enable VK_KHR_maintenance4 to relax the stage interface mapping.
* Removes most vulkan validation warnings/errors.
* Detection of frame buffer changes that needs to be applied before
performing a command requiring render pass (draw/clear attachment)
**Benefits**
* Late retrieval of a swap chain image results in better overall performance as
Blender doesn't need to wait until the image is presented on the screen.
* Easier API and clearer state (transitions)
* More control over Image layouts and command buffer states. (Better alignment with
Vulkan API)
Pull Request: https://projects.blender.org/blender/blender/pulls/111473
Extract a mask from the stencil buffer and use that texture instead
when texture views are not available.
Needed for supporting the Windows ARM software driver.
The workaround is isolated on its own class so it's easy to remove once
it's no longer needed.
Note that while this adds a function to check if texture views are available
(`GPU_texture_view_support`), at the moment this always returns true in
practice, since OpenGL 4.3 is the minimum supported version.
A separate patch will be needed to allow Blender to run using
OpenGL 4.2 + extensions.
Pull Request: https://projects.blender.org/blender/blender/pulls/111402
Vulkan device was deallocated, but when destroying the GHOST context
the GPU context is reactivated and want to allocate buffers lazilly.
This is solved by de-initializing the device on platform exit, resetting
buffer pointers so double free can be detected.
Pull Request: https://projects.blender.org/blender/blender/pulls/111462
When GLSL sources were first included in Blender they were treated as
data (like blend files) and had no license header.
Since then GLSL has been used for more sophisticated features
(EEVEE & real-time compositing)
where it makes sense to include licensing information.
Add SPDX copyright headers to *.glsl files, matching headers used for
C/C++, also include GLSL files in the license checking script.
As leading C-comments are now stripped,
added binary size of comments is no longer a concern.
Ref !111247
