New Studio Feature - CollisionFidelity.PreciseConvexDecomposition (Enabled Globally)

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:

The original mesh of a curved tube

Collision before

Collision after

There are still some slight imperfections where it isn’t perfectly smooth but it’s not even comparable to before.

Imperfection

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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!
:heart:

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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 @CloneTrooper1019 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. :frowning: 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

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Can you please PM me the tree trunk? I want to see whats up with that.

Updated the original post to mention the Beta Feature more directly.

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Sent!

I didn’t realize it was a Beta Feature but still managed to select it using the arrow keys.

Edit: Selecting using arrow keys was my problem. The collision mesh looks amazing with only 30% more data added to my save relative to CollisionFidelity.Default:

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I cannot express how much I love this update! It’s incredible!! Thank you so much, you are a hero!

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interesting. This could possibly lead to liquid simulation, but right now I have no use for this.

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Awwww bummer, I was hoping for better composition in crevices/bowl shapes so that when I paint debris on rocks, it can bunch up like it would in nature! However it is better than before for the more open, smooth surfaces of rock


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This is amazing. I can finally avoid having to decompose some of my meshes into 20 convex surfaces, although an Exact option is still required in some cases.

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Can’t wait to make some roads in Blender since it’s so much more convenient and efficient, and have them actually collide properly in studio!

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Mac.

Since fast flags are engine-level, why couldn’t you just not make PreciseConvexDecomposition exist if it’s not enabled?

(Assuming this was a fast flag, I never got an answer on that)

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This has been enabled in studio for a while but just crashed it until now- I’m glad it’s not teasing me anymore lol
However, a little disappointed it didn’t fix my primary use case- shadows.

The shadows on this more accurate geometry is somehow even worse than Hull?? I just want to be able to make unions with good collisions and shadows without it looking like crap. :confused:

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I Just spot on been wanting that for a long time thanks!!

1 Like