Calinou
commented
3 years ago Related to https://github.com/godotengine/godot-proposals/issues/2745.
This is a good idea overall, and it will come handy when using shadowmasking on low-end setups too (so you can enable shadows only for static objects).
Another benefit of having a shadow cull mask is that you can use a projector texture without actually casting any shadows (by disabling all shadow layers). This is useful to use a light with a projector texture without increasing the performance demands too much compared to a non-shadowed light.
For directional shadows, we may want to have more control over which splits an object will be included in. For instance, small fixtures don't need to be included in distant shadow splits as they will never cast noticeable shadows. This could perhaps be done automatically (e.g. using an object's AABB size in relation to the camera distance), but it may be too expensive to perform checks every frame for this.
mrjustaguy
Lielay9
jams3223
Vukbo
EMBYRDEV
Describe the project you are working on
Open Environments
Describe the problem or limitation you are having in your project
I need to Specify which Lights cast Shadows from which objects, to optimize for performance, Currently only things I can do are Disable the Shadows from said geometry from every light, or none at all, which is bad in instances where for example, you know a Directional Light will always be in Shadow, but an Omni Light or Spot Light might not.
Currently Only Light has a cull mask, but that doesn't affect Shadows, just determines if the object is lit by the light (in 4.0 atleast, haven't tested in 3.x)
Describe the feature / enhancement and how it helps to overcome the problem or limitation
Add Cull Mask for Shadows, This allows for cutting objects out of the Shadow Rendering Equation, for specific Lights (or telling the lights to render simplified shadows that might not work for every light casting shadows)
This can be used to greatly optimize Shadow Rendering in some scenes, without sacrificing Shadow Quality, at the expense of more artist time spent creating content and increasing performance, but doesn't hurt the workflow of those that don't invest the time to optimize like this.
Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams
Add Cull Mask to Shadows, just like there is a Cull Mask for calculating Light for object types.
If this enhancement will not be used often, can it be worked around with a few lines of script?
No, currently Shadow Casting is Binary, All Lights casting shadows go one of two routes: you cast, or you don't, for all lights lighting an object, no way to tell one group of lights to cast, and others not to cast for a given object.
Is there a reason why this should be core and not an add-on in the asset library?
Rendering is Core.