Sun Shadow map resolution?

Hi @jeff and @wim
I have a question about shadows in OpenGL (again :wink: )
And I wonder if it is possible to make the sun shadow a higher priority when it comes to memory consumption for shadow maps?
Even if I drag the shadow memory consumption slider all the way up to 1GB I still get jaggy shadows, is the suns shadowmap limited to 1024x1024 pixles?

On the image to the left I have matched the top view so it aligns with the sun, and these are all the visible objects in the file. On the right you can see the shadow resolution ( I lowered the smoothing to better see the pixles)

PS! Groundplane is turned off

For architects and landscape use it would be great to have a priority slider for the sun, as this shadow is often much more important (for sun studies etc) than the soft shadows from the skylight.

Hope that makes sense.

Here you can see the default shadows from when I reset rendered mode:

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Boosting this post to see if there’s some resolution (haha) to this issue.

Here’s an example of some brutal shadows. I’m running a nvidia 4090, certainly we can put that thing to better use than this somehow.

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After some experimentation, here’s a workflow that allows higher resolution shadows for certain applications.

The trick appears to be that rhino will split the resolution of your shadows across all objects that are potentially visible, not just what’s shown in the detail. You can get around this by turning off all objects that aren’t visible in the detail.

This won’t help folks looking for instant cheap perspective renders in detail with high resolution shadows, but it does get elevations/sections similar to what Revit can do (with more flexibility than Revit and less pain).

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hi @Clayton_Muhleman Is this a model you could share with us to have a look at? I can then ask the developers to see if this can be optimized so you don’t need this workaround. If it is a confidential model, use Rhino - Upload to Support and link back to this thread, thanks

Hi @Gijs, you bet. I’ll send a file over via the support link.

thanks, looking into it

@Clayton_Muhleman All your views are in wireframe, and I have a hard time finding the detail you are showing, any pointers?

@Gijs Hmm, I’m guessing that’s because you’ll need the visualarq plugin to access the display styles on that model?

@Clayton_Muhleman I think knowing which detail the screenshot was taken in, should be enough, for the rest I can see that hiding geometry can sharpen shadows.

@Gijs Ah, I understand. That’ll be the top detail on on sheet A3.0 - North + South Elevation. There’s two overlapping details, one with shading and one with lineweights.

In case of your model @Clayton_Muhleman the quality of shadows can be improved by unchecking ‘cast shadows’ for the surroundings, or basically for as much as possible for what is not affecting the casting of shadows. In case of @Holo 's model, it will be harder, since the building covers the whole site.
I’ve filed RH-75201 Shadow settings, allow to use more memory

Yes, I think I’ve been accomplishing that by turning off all the site layers in details that need shadows. Manually selecting objects and disabling shadows would also work. @Holo’s model probably won’t work with that workflow since he’s trying to show the entire site instead of just an elevation/plan etc.

Thanks for looking into it, @gijs!