It was… crashing before? That is very not good, it was simply supposed to block you from setting it! Did you report that previously?
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No, thought it was my specific studio. Guess you forgot to remove the option from the dropdown when the feature wasn’t enabled? Was it under a fast flag for a while, present but disabled? That would explain it.
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Will we ever have access to geometry data within studio? If not, are there any alternatives to retrieving geometry data outside of studio? I’d like to have support for meshes and CSG models on my own collision engine, but I haven’t found a way to get Roblox’s generated geometry.
Since you have to upload meshes to Roblox, I’d assume you could download the data somewhere?
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No plans for this right now.
The drop down wasn’t removable, but I made to the option was “grayed out and unselectable”. Are you on Mac or PC?
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feature good, good faeture i like it, good. reply good, good reply., yes good. very physics have collide, very cool and realistic colide
(P.s. I love this, it’s the solution to all of my CSG problems)
11 Likes
No more mesh splitting. No more making your own collisions. No more unneeded pain and suffering. Thank. You. So. Much.
Edit: I was playing around with this. This is much more powerful than we all think.
Here’s a hallway I made that was previously restricted (& dropped) due to the lack of collisions.
Mind you, this is all meshparts.
What it looks like:
Before:
After:
29 Likes
This is kinda hot though, thanks a lot for this. This’ll make alotta peoples’ lives easier. I know it’d make mine easier… XD
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I made a road model in blender to see how well the new feature works.
There’s only one odd area on the decomposition geometry, but that can easily be fixed by tweaking the mesh inside of blender.
This is an amazing update! I can see car games switching to meshes for their roads in the near future. Hopefully the minor deformities are gone by the time the feature comes out of beta, but so far, the geometry is pretty spot on for 99% of the mesh.
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Part of how the algorithm works is that, when it thinks its safe to combine objects into a convex hull it has some sample points along the original triangle surface input and it raycasts outward. If it hits the back surface of a convex hull, it measures the distance.
Currently the “max allowed” distance is set to be 1/100 of the bounding box of the average shape, meaning you can close a concavity that is 1% of the shapes bounding box size. Do you mind PMing me the mesh so that I can make sure this is performing within those restrictions?
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I sent you the mesh, but I’d like to point out that I’m a horrible modeler and there’s probably an error on my end.
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I have been waiting for this feature for a long time! Thank you, you are appraised!!
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Great feature I’ve been wanting for a long time.
For example:
There are still some slight imperfections where it isn’t perfectly smooth but it’s not even comparable to before.
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Yeah slight imperfections that extrude 1/100th of the boundingbox length from the surface is something that can happen with the algorithm. (See my previous reply to Hobbyist_Games above).
My hope is that in the future I can expose the “tuning” of the algorithm so that users can define the “distance” of acceptable imperfections.
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Yea, this would be great!
Otherwise, this really is one of my favorite feature of 2020 and it’s personally going to be quite useful for my project. I already feel like I’m going to have quite some fun playing around with that!
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This is soo cool! I can imagine alot of things possible with this now. Yesterday I was making a test of a earthquake where the ground “breaks” in half using SubtractAsync. But you couldent fall into the hole that it was making because of the collision. I think this will make it possible thanks alot!
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Here’s a plugin by @Maximum_ADHD that allows you to toggle the ShowDecompositionGeometry setting, it is very handy for trying to limit your “PhysicsPart” memory by sacrificing some collision accuracy
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THIS IS INCREDIBLE! Smooth slide time!
EDIT: This slide mesh is still broken up into sixteen pieces.
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This is great! The physics generator is impressive, but there are still so many cases where I know exactly what I need but the results are far too complex (or don’t match the geometry.)
The worst experience I’ve had is with this cherry tree trunk. I spent hours trying fit a small burrow into the tree for tiny pets to use, but everything I tried was unusable.
I tried using PreciseConvexDecomposition on it and it resulted in a crash. I’m not sure what I expected considering how complex the small roots are. I know exactly how I want to approximate the roots, there’s just no way to do it.
I could try approximating it with invisible parts, but what I need is already in the engine, I just need the tools! I’ve started seriously considering reverse-engineering the physics format so I can make my own physics editing tools, or at the very least copy/pasting mesh data manually from .rbxlx files for similar meshes that could reuse the same physics data.
There are also common cases that could be approximated with a sphere or non-axis-aligned cylinder/box.
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I can’t seem to enable this; the option is not selectable in the dropdown menu for me
Whenever I try selecting “Hull” (The second-to-last option) and then pressing the down arrow, studio crashes.
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I was able to select this as an option weeks before this feature was released as well (only by pressing the down arrow on the dropdown; I couldn’t mouse over it. See the video above.), but it was crashing studio
Now I’m still getting the same thing, where I can’t select it with my mouse, can select it with the arrow keys, but studio crashes whenever trying to enable it. Re-installing Roblox Studio doesn’t seem to work.
edit: Oh, I didn’t realize from this post it wasn’t live live. 
I forgot to enable the beta feature
However, it seems that when I disable the beta feature, meshes that I set to PreciseConvexDecomposition still retain their hitboxes
3 Likes