Smoothing Groups



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    Lucia CR

    are you referring to something like this (an older request):

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    Benjamin von Cramon

    A Smoothing Group is actually a very different thing from what's described in your link. It's also a lot easier to implement as this only affects what happens between faces, be that a sharp line or some amount of smoothing per face/face junction. Here's link to a page explaining it regarding 3DS Max, but in my case, I need this function because of Unreal Engine requiring Smoothing Groups to not display the choppy look of faces without at least one global Smoothing Group. One Smoothing Group is fine for the whole Component, not necessary to assign different value per group, as other modelers do when generating objects and such.

    The link you provided, I have to admit, would be far more meaningful to the community, to all of photogrammetry! The blobbyness one user describes on planes, lines that are supposed to be smooth/straight/curved, etc. is related to how a point cloud is tessellated to a polygonal mesh. Here's how I understand the problem. When I walk into a room and look around and see the ceiling, the joints to the four walls, in turn to the floor, my quick (and dirty) mental map makes the surfaces planar and the junctions into straight lines. We know construction, obliquely shining a flashlight across the walls reveals dips and out of plumb joints. This works across scale, the door faces of cabinets, CD cases, etc. To the computer, specifically the algorithm in an SFM solution used to tessellate so many vertices in a point cloud into a mesh, there are no "ideas" in the computer to say, "this wall is flat", "this point is a corner", so connecting the dots doesn't feature the upside of the quick and dirty mental maps we have going on. 

    Here's an example, my cabinets, wide view seems okay:

    If you look closely, the cabinet faces are smooth (after manual smoothing) but the edges are rough (no tool for that). Now look at the CD cases and edges of the cabinets, this with 42 MP images shot low ISO, some at 2 M distance, many at .2 M distance, several hundred, so plenty of good photos:

    I'm told this is a huge challenge others have been working on, anybody who can solve it wins big, as presently the entertainment industry (film and video games) might use scans, but only as a template, environment artists have to go in (especially manmade environments featuring smooth lines and shapes) and remodel everything, so this would be a game change saving millions if digital assets for virtual sets were truly procedural. Photogrammetry is to virtual sets today as the camera was to painting portraits and landscapes back in the 1830s. People cried, "Art is dead", and so the artist, but no, many of us put down the paint brush and picked up a camera.

    The way forward is clear, your team can do this, superb mathematicians they are. There's much discussion these days about AI and the use of neural networks to solve all kinds of problems. I'm not a mathematician, but if I understood the mechanics, the "I" in "AI" tells us what we need to know. If the general vector of a series of points takes off from a general cluster of points along three axis at a roughly 90° angle, that's a corner and so is that cluster at the other end of each of those lines and all the polys falling within four such lines is basically a plane. We wouldn't want too be to rigid in these rules,  make the line too hard, the corner too sharp, would look fake, real world when you get up close shows the corner is more of a cup shape. So allow for some averaging, rules feature a weight, which has the added benefit of not forcing the model off from actual imperfections such that nothing then fits. 

    If RC wants to make yet bigger waves in this space, that's my 2 cents. Love the software, but I'm limited to what projects I can sell, and if a procedural means of digitizing manmade environments isn't viable, we both lose out.


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    Lucia CR

    thank you for the additional information.

    currently you can use the smoothing tool (recently improved) to smooth the surface of a selected model, so you would like to expand this feature to all models in a component at once then?

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