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Tesselation Quality of updated Render Studio (Beta)

martin_kopplowmartin_kopplow Member Posts: 393 PRO
I've been doing some mounting instructions recently. I already made a few before the update of May 17th and am now trying to do some more, but I can't get the tesselation quality I had before the update. Also there appears not to be any UI for this and no documentation yet.

Sample Images with a lot of round things, done before May 17th:
See how all the curves, even the large radius ones, are almost round with hardly visible tesselation? That is a reasonable quality which I need.

Here's one image rendered after May 17th:

Note the handlebar grip end, the grey cable and the clamp in the image center and other coarsely tesselated silhouettes, which are all meant to be as smooth as in the firtst two images. I obviously can't deliver the latter after I already delivered the former. How to control and improve tesselation after the update?


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    Paul_ArdenPaul_Arden Member, Onshape Employees, Developers Posts: 187
    Documentation for tessellation can be found here. The settings are now accessed from the right click menu on the scene list.

    Scene list context menu

    Since there is no longer a conversion step, tessellation can be dynamically changed at any time. Like Onshape, Render Studio now uses a default tessellation (using the same technique) which can then be overridden at various levels of the scene list depending on your requirements (it also respects any customised tessellation settings for parts that were set in Onshape Part Studios).

    You can set the tessellation at the top level if you just want everything to have the same tessellation or override individual Part Studios, Assemblies, sub-Assemblies and parts.
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    martin_kopplowmartin_kopplow Member Posts: 393 PRO
    edited June 3
    Ah, thank you, though there is still a little confusion about this. The documentation says ANY list object, but I don't get the menu on RMBing the render studio list item itself, not on subassemblies, and also not on individual faces. I only get it at the top level assembly and on parts. Faces only when I activate them from their part list item (Select Children). Also, the first object I made changes to (Tesselation set to very fine for the handle) was immediately retesselated and quality increased noticeably. I could not do that with any other object after that, though: Changes were entered in the edit dialog, and still reflected there, but that made no difference in their appearance in the render scene (E.G. cable and clamp). Not in preview and not after a rendering run.

    I went into the part tab and changed the tesselation from the part appearance. When creating a new render studio, this works and tesselatiion is displayed in a higher quality for those parts. I created a new version, then went back to the old render studio and updated to the latest version. Nothing happened. The custom tesselation on one of the parts I tried read -37,458 degrees and -1000mm chordal deviation now, which puzzles me a bit. I entered 2° and 0.1mm.

    All this is a bit difficult to understand, especially because I can probably not know which parts or faces need finer tesselation settings before I create a render studio for an assembly and get at least a preview. I also don't want to slow everything down by using unnecessarily fine settings just on a suspicion. So tesselation needs to be edited inside a render studio and maybe also carried though from the model with versions, though I think the render studio should override model tesselation. Else, close- up renderings of small parts used several times in assemblies would result in many highly tesselated objects in large assemblies, where they make no sense.

    Did I miss something here, or is all this not yet fully consistent?
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    Paul_ArdenPaul_Arden Member, Onshape Employees, Developers Posts: 187
    Actually I was in error regarding setting the tessellation at the very top level, that currently isn't possible while the documentation states that it is, we'll either implement support for that or update the documentation.

    Currently what can have tessellation set are the top level insertions of Part Studios, Assemblies and Parts and Parts within Assemblies, within Sub-Assemblies and within Part Studios. It is currently not possible to set tessellation on the entire Render Studio, Sub-Assemblies or individual faces.

    There are however a few known bugs with the tessellation settings that will be fixed in the next release. Some of these result in the tessellation changes not being immediately reflected in the viewport (but showing up after reloading).

    For the negative values, this is a known issue and can happen when you switch from Auto to custom since the values for Auto are currently set to -1, so they get converted from radians and meters to your workspace units, resulting in the values you saw. When combined with the other bugs this can result in those values being stored. They should behave the same as it Auto was selected until you change them to something else.

    While tessellation does still impact Render Studio, it is to a much lower extent than the Onshape viewport as the rendering technique is completely different and runs on known hardware on our servers. So while you can still get into trouble with a very complex scene and crazy high tessellation, the limits are quite a bit higher. Selecting the top level insertions tessellation to match what you previously used in the old Render Studio should however give similar results.

    I would suggest that if you are still seeing issues after the next release (which fixes those bugs I mentioned) then definitely file a ticket.
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