add constructor for btcollisionworld

[sancelot]

No description provided.

[sancelot]

refs #181

[bdiblasi]

I am currently receiving the error: 'cannot construct a btCollisionWorld, no constructor in IDL' when trying to implement the collision world in accordance with the Bullet Collision Interface Demo. I looked through the history on this topic here and it is unclear to me whether or not this feature is supported. I unfortunately cannot contribute, but I wanted to submit my findings for review.

[willeastcott]

btCollisionWorld is the base class for the various sub-type worlds.

https://pybullet.org/Bullet/BulletFull/classbtCollisionWorld.html

PlayCanvas uses the btDiscreteDynamicsWorld subclass:

https://github.com/playcanvas/engine/blob/dev/src/framework/components/rigid-body/system.js#L329

It does appear that btCollisionWorld does appear in the IDL though:

https://github.com/kripken/ammo.js/blob/main/ammo.idl#L863-L879

So I'm a bit confused why you get that error.... 🤔

[bdiblasi]

Just as a point of reference, I was blindly following the Collision Interface Demo. Thank you for the resource links.

A separate, unrelated note, is that I am trying to implement custom game physics for my character controller. It seems like kinematic bodies do not provide collision data when they contact one another, and that is the reason I've gone down this path. I planned to use pure collision detection, get the world normal of contact and implement game physics accordingly. Would you have any suggestions for a better implementation strategy? I'd like to stay 'in-the-box' with playcanvas since I am also trying to use ammo.js in my multiplayer node.js server, but I'm not sure it will fit.

[bdiblasi]

I've gotten a similar response whether using the built-in 'Import Ammo' tool, or pasting the raw ammo.js build into a separate script and running the promise.

[sancelot]

this is available in my fork sancelot@bfc9eb5 Le ven. 25 févr. 2022 à 13:21, bdiblasi ***@***.***> a écrit :

…

I've gotten a similar response whether using the built-in 'Import Ammo' tool, or pasting the raw ammo.js build into a separate script and running the promise. [image: collisionWorld] <https://user-images.githubusercontent.com/84610810/155714342-1abf3326-891c-41b1-bf91-e5202a442177.png> — Reply to this email directly, view it on GitHub <#356 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAA57OZM64I4NSA4DZQ2ETLU45X25ANCNFSM4XFM2ARA> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[bdiblasi]

I can see that you modified the ammo.idl file. It looks like the ammo.js file is not updated, is that correct? I do not know how to build the ammo.js file from your fork, if you have a minute could you give me some pointers?

[sancelot]

you have to install emscripten compiler and build the projet.

[sancelot]

but it would be nice if @kripken could merge it.