Rhino 6 Bug: Grasshopper Hidden Geometry Showing in Rhino Rendered View

In the SR8 release of Rhino 6, I’m encountering a display bug between Grasshopper and the Rendered Display Mode (or any of the similar Display Modes like Arctic and Raytraced). For some reason geometry that is completely hidden in Grasshopper is appearing in the Rhino Viewport if it is set to Rendered, Arctic, etc. but it is not there in Wireframe, Shaded, etc. See the images below.

The long arcing polysurface that can be seen in the Rendered and Arctic views was created in Grasshopper and a custom material and custom preview component. The Box is simply Rhino geometry.

I’ve tried changing the settings of Rhino’s Render Mesh in order to force it to recalculate the current scene but the hidden GH geometry is still there. Any ideas on how to get rid of the GH preview geometry? I’ve turned off Preview for both the Grasshopper Component and Grasshopper’s global Preview.
Attached are the Rhino and Grasshopper Files. I’m on a Macbook Pro running Bootcamp with Windows 10.
Grasshopper_Preview_Bug.gh (14.6 KB)
Grasshopper_Preview_Bug.3dm (9.4 MB)

This works as it is supposed to. To hide the geometry piped into the custom preview component in Rendered, Arctict and Raytraced you need to disable the Render entry of its context menu


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Huh, that’s new. Thanks. But it also seems a bit strange. Shouldn’t hiding the component hide the preview of the geometry in Rhino? Furthermore, shouldn’t turning off GH’s global preview turn off the preview? If I had dozens of these custom render components, I wouldn’t want to have to right-click on each one to turn off their rendered preview. It seems like if the “Don’t draw any preview geometry” option is On, then nothing from GH should be rendered, right? So, I’ll still call this a bug as there seems to be a conflict between the local and global settings for previewing geometry. In addition, I’d also say that if now turning Preview off on a component doesn’t actually turn it off, you are confusing users. Maybe not a bug, but just bad UX.

Rendered, Arctic and Raytraced are bit of different in that they use custom render meshes to do their geometry drawing. The Custom Preview component was chosen to shoehorn the GH geometry into the pipelines of those so that they are able to properly render them. I’m not saying the user experience is the best, just stating how it is now.

Looking at this more, it seems like the “render” option on the custom preview component is unnecessary. The two previous options (Preview and Enabled) seem to do everything a user would need. If you don’t want it to calculate the render, then simply turn off Enabled. If you are fine with GH calculating the render, but you just don’t want to see it, then you would turn off the Preview. What does adding “Render” to the right-click options accomplish? Is there a use case that I’m not seeing that makes this option necessary and good?

Got it. Seems like a future update could fix this so that the UX isn’t as confusing and redundant. I appreciate now being able to preview GH geometry in the Rendered, Arctic, and Raytraced views, but I think the local and global controls for turning previews on/off should still work. Thanks for the explanation.

I think this is one of the items we’ll discuss when @DavidRutten visits our office in some weeks.