The existing behavior was surprising for users who draw opaque objects
into a semitransparent views, and this was especially evident with
the labels in `TextureLinearInterpolationTest`.
We now disable blending for MASKED, which is what our existing materials
documentation already says. We also now set the fragment alpha to 1 when
the fragment is not discarded, which prevents the "punch through"
effect. This is consistent with ThreeJS.
Fixes#4576.
This works by first generating a reflection buffer which gets blurred,
then the color pass samples from this buffer according to the roughness
of the surface being rendered.
A lot of the changes here involve utilizing "reserved" variants for
the new "SSR" pass and all the fallout from that.
Bring color grading back into the Rec.709 color space to match
previous behaviors. This change also implements an exact inverse
tone map function for the "Filmic" operator.
This helps prevent over-darkening but it's an artistic hack.
We need to check how we compute the bent normals as it seems we
find occlusion where there is no occlusion. The effect is
particularly visible on clear coat materials like a car's body.
* API CHANGE: honor user-defined precision, rename SamplerPrecision.
matc now honors 'precision' on non-samplers in mat files, and
the filamat API now allows clients to specify precision for
non-samplers.
This involved flattening a union that is internal to filamat.
* MaterialBuilder: Add Java bindings for precision.
* Add support for transparent shadows
This solution uses an 8x8 Bayer matrix. We could find a better
noise. We also need better filtering of the shadow maps. A PCF
is barely enough and VSM fails without blurring.
* Use a fixed Bayer matrix, fix pre-caching of depth shaders
* Use gradient noise instead of fixed bayer pattern
* Update docs
* Materials can now provide custom lighting/shading
When a material uses the "lit" shading model, customSurfaceShading can
be enabled to replace Filament's lighting implementation. When this
feature is enabled, the material *must* provide the following function
in the fragment shader block:
vec3 surfaceShading(
const MaterialInputs materialInputs,
const ShadingData shadingData,
const LightData lightData
) {
return vec3(1.0); // custom lighting here
}
Please refer to the docs in Materials.html for more information about
this feature and the different values provided by the data structures
passed to the function.
* Update docs
* Update docs/Materials.md.html
Co-authored-by: Philip Rideout <philiprideout@gmail.com>
Co-authored-by: Philip Rideout <philiprideout@gmail.com>
We used to have that before, but it was hardcoded and depended on
mobile vs. desktop.
With this change, users can set the quality on the material itself.
The default match the current settings. There are 3 quality levels:
low: enables optimization that might not be 100% correct
(e.g. abs(x) instead of sqrt(x*x))
normal: like low, but doesn't sacrifices correctness.
high: could be improved upsampling, etc...
* Add support for sheenColor and sheenRoughness
This work is necessary to support the glTF extension KHR_materials_sheen.
This change effectively adds the specular lobe from the cloth material
model to the base material model. The cloth model remains useful for
its extra subsurface color feature but also because it's cheaper.
* Add support for KHR_materials_sheen to gltfio
* Update documentation
* Document default shading values
This chooses type=THIN, mode=SCREENSPACE, and blending=TRANSPARENT.
Due to sampler overload, we print a friendly error message and enable a
fallback if the user tries to simultaneously enable ubershader mode, the
clearcoat extension, and the transmission extension.
This fixes dynamic lighting and SSAO when a viewport is not in 0,0.
In practice this currently happens only when all post-processing is
disabled.
Instead of using gl_FragCoord we introduce a new API,
getNormalizedViewportCoord(), which as the name implies returns
normalized [0, 1] viewport coordinates with origin at the bottom-left,
on all platforms.
This is implemented in this PR by interpolating gl_Position.
Emissive was previously defined in exposure compensation stops, which
was confusing to many. It is now a value in nits, with the alpha
channel controlling how much the camera exposure affects the emissive.
At 0, the emissive value is just added to the final pixel color, at
1 the emissive value is multiplied by the exposure just like with
regular lights.
The intensity of the emissive property can be computed from an
exposure value (EV) easily with the following formula:
emissive.rgb = emissive.rgb * pow(2.0, EV - 3.0);
This formula is available as Exposure::luminance(float) already
in Filament.
The user can now choose amongst 3 specular AO methods:
- None, specAO is off
- Simple, specAO is inferred from roughness and diffuse AO
- Bent normals, specAO is computed accurately from cone intersections
The last method is more expensive but produces the best results.
This change also fixes a few issues:
- Rename materialRefraction() and materialRefractionType() for
consistency
- Fixes user time in shaders
* Add support for bent normals
Bent normals can be enabled via the bentNormal property of a material.
When specular occlusion is enabled, bent normals improve the quality
of the computation.
* Save a couple of multiplications in bent specular AO
When dealing with thin objects we really have two thicknesses to
consider, the thickness in the direction of the normal, which
corresponds to the value used for solid objects, and the thickness of
the object's walls, which generally is a constant.
Reusing thickness in the later case is problematic for assets that have
a thickness map, but are rendered hollow.
In the future we can even imagine handling double-sided hollow objects
by using the thickness information -- e.g. a hollow cube.
Normally the IOR is deduced from the reflectance, but now we allow to
specify the IOR instead or in addition to the reflectance.
In the later case, it's possible to create physically impossible
materials, but this can be useful for artistic reasons.
* Add the ability to modify clip space coordinates in the vertex shader
This introduces MaterialVertexInputs.clipSpaceTransform, a mat4 that
is applied to gl_Position before exiting the vertex stage.
* Address code review comments
Inspired by our recent scissor change (#1639) but motivated by gltfio,
which was forced to create a ton of ubershaders (see #1562).
Tested with:
gltf_viewer -u ../glTF-Sample-Models/2.0/TextureSettingsTest/glTF/TextureSettingsTest.gltf
* Improve materials under white furnace test
Two major changes:
- Mobile target now implements a cheaper variant of the off specular
peak bias (which moves the reflected vector towards the normal).
This greatly helps with rough surfaces that may otherwise point
toward a bright part of the IBL.
- The indirect diffuse love is now properly attenuated to avoid adding
the energy reflected by the specular layer. This allows dielectrics
to be correctly energy conserving under a white furnace.
- Tweak the (hacky) clear coat layer attenuation to behave properly
under a white furnace.
* Use the same reflected vector modification everywhere
This works by aliasing CUSTOM0 - CUSTOM7 to morphing attributes, and by
extending our existing skinning variant.
This PR was tested against some upcoming changes to gltfio.
Issue #1149, #1417
This is a prep step for the upcoming morph feature and does not require
a bump to our material version number.
Stay tuned for a new sample app that demonstrates this feature.
* Add screen and multiply blending modes
This change also fixes a sorting issue: different sorting modes
were sorted in different buckets which is incorrect. We want
to sort only by distance.
* Update release notes and Java API
* Fix build error
This replaces the previous "curvature to roughness" method. Both are related
and rely on the screen space variance of geometric normals but this new
solution offers more control (the screen space variance and the clamping
threshold can be controlled).
