I made an empirical test with a 100% diffuse sphere and manually tweak the
lighting power of a sun lamp trying to fit cycles and eevee the best I can.
Then I plotted the result and found a rough fit to the equation and that
seems to work pretty well.
This makes it possible to tweak indirect lighting in the shader.
Only a subset of the outputs is supported and the ray depth has not exactly
the same meaning:
Is Camera : Supported.
Is Shadow : Supported.
Is Diffuse : Supported.
Is Glossy : Supported.
Is Singular : Not supported. Same as Is Glossy.
Is Reflection : Not supported. Same as Is Glossy.
Is Transmission : Not supported. Same as Is Glossy.
Ray Length : Not supported. Defaults to 1.0.
Ray Depth : Indicate the current bounce when baking the light cache.
Diffuse Depth : Same as Ray Depth but only when baking diffuse light.
Glossy Depth : Same as Ray Depth but only when baking specular light.
Transparent Depth : Not supported. Defaults to 0.
Transmission Depth : Not supported. Same as Glossy Depth.
Caveat: Is Glossy does not work with Screen Space Reflections but does work
with reflection planes (when used with SSR or not).
We have to render the world twice for that to work.
This is a nasty bug. Because the node does not get properlly tagged as SSS
(sss_id is 0) but is still evaluated (so tagging the GPUMaterial as having
SSS). The sssProfile UBO is still declared and we need to bind something
to it.
This option make the internal render size larger than the output size in
order to minimize screenspace effects disapearing at the render edges.
The overscan size added around the render is the maximum dimension
multiplied by the overscan percentage.
It is caused by some sync issue apparently. Adding glFlush in these
two places fixes it.
Caveat: it might have a small perf impact (did not measure it).
The fix is limited to the affected driver/operating systems.
This new option is located in the shadows options in the render settings.
This approach is simple and just randomize the shadow map position (not
the lamp itself) and just let the temporal supersampling do the average of
all the shadowing. The downside is that is needs quite a large number of
samples to give smooth results and individual sample position can remain
visible.
Enabling this option will make the viewport refresh all shadow maps every
redraw so it has a serious performance impact.
This approach is not physicaly based at all and will not match cycles.
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The sampling for point lamps (spheres) is not
Adding a workaround in this case: we blit the depth buffer instead of the
stencil buffer and use the copy as the texture. This is slower but at
least it should work.
NOTE: There is a float imprecision near the focus plane
due to the current technique used for DOF. This makes the alpha channel
transparent on nearly in focus objects even when they should not.
This artifact should be fixed when the DOF will use scatter as gather for
low brightness areas.
Fix T57042 : Eevee does not render alpha when DOF is turned on
Encountered on Nvidia + Linux, it seems that doing everything all at once
can make the driver give up the whole command list and return nothing as
the output of the render.
This implementation is a bit hacky but match cycles pretty close.
If pixel size is not enabled, it will use the geom shader to
compute distances between vertices. This will have a cost.
Implementation is a bit hacky in gpu_codegen to make the geom shader works
in an optional manner.
