Previously only scalar displacement along the normal was supported,
now displacement can go in any direction. For backwards compatibility,
a Displacement node will be automatically inserted in existing files.
This will make it possible to support vector displacement maps in the
future. It's already possible to use them to some extent, but requires
a manual shader node setup. For tangent space maps the right tangent
may also not be available yet, depends on the map.
Differential Revision: https://developer.blender.org/D3015
This converts object space height to world space displacement, to be
linked to the new vector displacement material output.
Differential Revision: https://developer.blender.org/D3015
This option prevent from automatically blurring the albedo color applied to the SSS.
While this is great for preserving details it can bleed more light onto the nearby objects since the blurring will be done on pure "white" irradiance.
This issue is to be tackled in a separate commit.
This cleanup removes the need of gigantic code duplication for each closure.
This also make some preformance improvement since it removes some branches and duplicated loops.
It also fix some mismatch (between cycles and eevee) with the principled shader.
This is a hack to make the user control the SSS radius even though the profile is baked with the default radius values.
This is completly against UI principles since you cannot edit the profile radiuses while there is something plugged into the radius socket.
Better solution will be to either have a dedicated node value for RGB radiuses and a SSS scale socket only for eevee.
This adds the possibility to simulate things like red ears with strong backlight or material with high scattering distances.
To enable it you need to turn on the "Subsurface Translucency" option in the "Options" tab of the Material Panel (and of course to have "regular" SSS enabled in both render settings and material options).
Since the effect is adding another overhead I prefer to make it optional. But this is open to discussion.
Be aware that the effect only works for direct lights (so no indirect/world lighting) that have shadowmaps, and is affected by the "softness" of the shadowmap and resolution.
Technical notes:
This is inspired by http://www.iryoku.com/translucency/ but goes a bit beyond that.
We do not use a sum of gaussian to apply in regards to the object thickness but we precompute a 1D kernel texture.
This texture stores the light transmited to a point at the back of an infinite slab of material of variying thickness.
We make the assumption that the slab is perpendicular to the light so that no fresnel or diffusion term is taken into account.
The light is considered constant.
If the setup is similar to the one assume during the profile baking, the realtime render matches cycles reference.
Due to these assumptions the computed transmitted light is in most cases too bright for curvy objects.
Finally we jitter the shadow map sample per pixel so we can simulate dispersion inside the medium.
Radius of the dispersion is in world space and derived by from the "soft" shadowmap parameter.
Idea for this come from this presentation http://www.iryoku.com/stare-into-the-future (slide 164).
How to use:
- Enable subsurface scattering in the render options.
- Add Subsurface BSDF to your shader.
- Check "Screen Space Subsurface Scattering" in the material panel options.
This initial implementation has a few limitations:
- only supports gaussian SSS.
- Does not support principled shader.
- The radius parameters is baked down to a number of samples and then put into an UBO. This means the radius input socket cannot be used. You need to tweak the default vector directly.
- The "texture blur" is considered as always set to 1
The algorithm averages normals from nearby surfaces. It uses the same
sampling strategy as BSSRDFs, casting rays along the normal and two
orthogonal axes, and combining the samples with MIS.
The main concern here is that we are introducing raytracing inside
shader evaluation, which could be quite bad for GPU performance and
stack memory usage. In practice it doesn't seem so bad though.
Note that using this feature can easily slow down renders 20%, and
that if you care about performance then it's better to use a bevel
modifier. Mainly this is useful for baking, and for cases where the
mesh topology makes it difficult for the bevel modifier to work well.
Differential Revision: https://developer.blender.org/D2803
It should behave like cycles.
Even if not efficient at all, we still do the same create - draw - free process that was done in the old viewport to save vram (maybe not really the case now) and not care about simulation's GPU texture state sync.
This is quite basic as it only support boundbing boxes.
But the material can refine the volume shape in anyway the user like.
To overcome this limitation, a voxelisation should be done on the mesh (generating a SDF maybe?) and tested against every volumetric cell.
You can now use a transparent shader as a completly transparent bsdf. And use whatever alpha mask in a mix shader between a transparent bsdf and another bsdf.
Since the change to prevent shader recompilation at every update, we got
a regression when clearcoat was used.
Basically at the shader build time we would determine if the shader
needed clear coat, and if it didin't, it would build a different GLSL
program.
However if later the user updated the clearcoat value so that it would
then require the full clearcoat shader, the user wouldn't get it until
manually forcing the shader to recompile, or reopening the file.
We now handle the optimization in the GLSL code. That adds a minimum
overhead due to branching. But the overall performance seems unchanged
(tested on linux in AMD and NVidia).
Reviewers: pascal, brecht, fclem
Differential Revision: https://developer.blender.org/D2822
This reverts commit 3888227a7b.
This "Fix" was made while ORCO was broken. Now that orco itself is fixed
this is no longer required, otherwise Tangent node produces different
results in Cycles and Eevee.
Orco should behave the same if it comes from unconnected vec inputs, or
from the Texture Coordinate -> Generated node output.
Fixup for 11e7e0769a.
This is related to T52528. The coordinates are still different between
Eevee and Cycles, but at least it behaves consistent within itself.
In fact the shader should now be correct, but the orco attributes we are
passing the shader seems to be where the problem is. But it's to be
tackled separately.
Since we started supporting the (Cycles) Material Output old files
stopped working. There is no reason to keep the original Eevee material
otuput anymore.
It includes doversion for old files.
Diffuse was not outputing the right normal. (this is not a problem with SSR actually)
Glass did not have proper ssr_id and was receiving environment lighting twice.
Also it did not have proper fresnel on lamps.
This commit separate the depth texture into another texture array.
This remove the need to output radial depth into alpha.
Unfortunatly it's difficult to recover position from the non linear depth buffer when applying reflection without adding a bunch of stuff.
This is in preparation of SSR planar reflections.
- Encode normals for other opaque bsdf so they are not rejected by the normal facing test.
- Early out non reflective surfaces.
- Add small offset to raytrace to avoid self intersection.
- Fix fallback probes not appearing.
Output in 2 buffers Normals, Specular Color and roughness.
This way we can raytrace in a defered fashion and blend the exact contribution of the specular lobe on top of the opaque pass.
Hashed Alpha transparency offers a noisy output but has the benefit of being correctly ordered. Noise can be attenuated with Multisampling / AntiAliasing.
The default anisotropic tangent computation could fail in some cases,
leading to NaNs and artifacts. Use a simpler formulation that doesn't
suffer from this.
This allow specialized shaders to redefine the closure interface to fit their needs.
For instance, Volumetric closure needs to pass more than one vec4 (absorption vec3, scattering vec3, anisotropy float).
