- Replace poisson by concentric samples: Less variance. They are sorted by radius then by angle.
- Separate filtering into 2 blur. First blur is 3x3 box blur. Second is user dependant.
- Group fetches by group of 4.
This brings some data structure changes.
Shared shadow data are stored in ShadowData (in glsl) (aka EEVEE_Shadow in C).
This structure contains the array indices of the first shadow element of this shadow "object".
It also contains how many shadow to evaluate (to be used for Multiple shadow maps).
The filtering is noisy and needs improvement.
- Use only one 2d texture array to store all shadowmaps.
- Allow to change shadow maps resolution.
- Do not output radial distance when rendering shadowmaps. This will allow fast rendering of shadowmaps when we will drop the use of geometry shaders.
Basically since g_data was malloc'ed (instead of calloc'ed)
g_data->minzbuffer was never initialized.
So when running DRW_framebuffer_init after EEVEE_effects_init, the test
to *g_data->minzbuffer would lead to unpredictable results.
This was caught by valgrind, reported by Sergey Sharybin.
This means we have less overall noise for rendered image.
SSR, AO, and Refraction are affected by this change.
SSR still exhibit artifacts because the reconstruction pattern needs to change every frame (TODO).
It's purpose is to limit the amount of light that spread across the screen.
Not entierly sure if it's very usefull, but it sure help to avoid to drown the screen in bloom.
This function was called to recreate the lower mip level of the probe texture. But this is not it's usage and it introduced a stall.
This patch add cubemap mipmap level regeneration in eevee_effects.c
This includes big improvement:
- The horizon search is decoupled from the BSDF evaluation. This means using multiple BSDF nodes have a much lower impact when enbaling AO.
- The horizon search is optimized by splitting the search into 4 corners searching similar directions to help which GPU cache coherence.
- The AO options are now uniforms and do not trigger shader recompilation (aka. freeze UI).
- Include a quality slider similar to the SSR one.
- Add a switch for disabling bounce light approximation.
- Fix problem with Bent Normals when occlusion get very dark.
- Add a denoise option to that takes the neighbors pixel values via glsl derivatives. This reduces noise but exhibit 2x2 blocky artifacts.
The downside : Separating the horizon search uses more memory (~3MB for each samples on HD viewport). We could lower the bit depth to 4bit per horizon but it produce noticeable banding (might be fixed with some dithering).
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.
I couldn't reproduce either, but calling min() with different argument
data types and indexing vectors with an index not known at compile time
seem likely to cause problems.
Ref T52404, T52404.
This fix a bug when occluder are on the edge of the screen and occludes more than they should.
Grouped the texture fetches together and clamp the ray at the border of the screen.
Also add a few util functions.
This effectivly reduce firefly bleeding all over the place.
We still need the clamp in the resolve pass because the level 0 has not been clamped.
NOTE: I did not clamped each sample individually for performance BUT I did not profile it to know how much it cost.
This was surely cause by float overflow. Limit roughness in this case to limit the brdf intensity.
Also compute VH faster.
Add a sanitizer to the SSR pass for investigating where NANs come from. Play with the roughness until you see where the black pixel is / comes from.
Theses Materials are rendered after the SSR pass.
The only difference with previous method is that they have a depth prepass (less overdraw) and are not sorted.
For the moment the only way to enable this is to:
- enable Screen Space REFLECTIONS.
- enable Screen Space Refraction in the SSR parameters.
- enable Screen Space Refraction in the material tab.
We track the previous ray position offseted by the thickness. If the sampled depth is between this value and the current ray position then we have a hit.
This fixes rays that are almost colinear with the view vector. Thickness is now only important for rays that are comming back to the camera.
As a consequence, this simplify a lot of things.
Also include some refactor.
Since we are working with non power of 2 textures, the mipmap level UV does not line up perfectly.
This resulted in skewed filtering and bad sampling of the min/max depth buffer.
We generate a 3D lut to precompute the btdf intensity.
I decided to use a 64*64*16 (N dot V, ior, roughness) because the btdf varies less with roughness than with IOR.
We also remap the ior to better use the space in the LUT.
It now uses a quality slider instead of stride.
Lower quality takes larger strides between samples and use lower mips when tracing rough rays.
Now raytracing is done entierly in homogeneous coordinate space. This run much faster.
Should be fairly optimized. We are still Bandwidth bound.
Add a line-line intersection refine.
Add a ray jitter between the multiple ray per pixel to fill some undersampling in mirror reflections.
The tracing now stops if it goes behind an object. This needs some work to allow it to continue even if behind objects.
