Search found 11 matches
- Sat Mar 05, 2016 10:49 pm
- Forum: Support and Development
- Topic: Messenger / Observer
- Replies: 8
- Views: 2863
Re: Messenger / Observer
You're right, it's implementation specific. What I more meant to establish was that you wouldn't overwrite existing things, though. And that, with the Love2d Win64 implementation, it tends to work out. I wrote a script that'd randomly insert and remove and, by my best estimate, it works as I describ...
- Sat Mar 05, 2016 7:55 pm
- Forum: Support and Development
- Topic: Messenger / Observer
- Replies: 8
- Views: 2863
Re: Messenger / Observer
The array would remain nicely compact even without doing that. In t = {1,2,nil,4,5,nil}, t[#t+1] would insert to the third slot, and then again would insert into the sixth slot. It'd also guarantee that you never accidentally start putting values into the hashmap part of the table. Perhaps an altern...
- Sat Mar 05, 2016 6:34 pm
- Forum: Support and Development
- Topic: Correctly misusing Box2d to get time of impact
- Replies: 6
- Views: 3595
Re: Correctly misusing Box2d to get time of impact
Also, I can tell you for a fact that you're wrong about velocity clamping. I just had an object move 2^32, and retain that velocity after update, by setting the timestep to 1/1000000000. So, as I read, velocity limits are purely a function of timestep.
- Sat Mar 05, 2016 6:08 pm
- Forum: Support and Development
- Topic: Messenger / Observer
- Replies: 8
- Views: 2863
Re: Messenger / Observer
Have you considered making subscriptions a weak list and having the creator of a subscription maintain a reference to it? Then, when you destroy the creator, the garbage collector will eventually swing by and remove it. A consequence would be that you'd have to change ipairs to regular pairs, but be...
- Sat Mar 05, 2016 4:41 pm
- Forum: Support and Development
- Topic: Correctly misusing Box2d to get time of impact
- Replies: 6
- Views: 3595
Re: Correctly misusing Box2d to get time of impact
My reading is that the velocity limit is 2 units per update, so at 60hz that's 120u/s. Do you know what the velocity is clamped to? And, I don't think you call world:update like I do. I call it a dynamic number of times depending on if objects are likely to collide or not. In all likelihood, most fr...
- Sat Mar 05, 2016 3:30 pm
- Forum: Support and Development
- Topic: Correctly misusing Box2d to get time of impact
- Replies: 6
- Views: 3595
Re: Correctly misusing Box2d to get time of impact
To make sure we read the same thing about the speedlimit, it's 2.0 distance units per world:update, right? I was not aware of this but I think I can see how to work around it. So an object moving 10m/s given a .1s timestep will move 1, but an object moving 30m/s given a 0.1s timestep will only move ...
- Sat Mar 05, 2016 2:33 am
- Forum: Support and Development
- Topic: Correctly misusing Box2d to get time of impact
- Replies: 6
- Views: 3595
Correctly misusing Box2d to get time of impact
Given two physics objects that collide, how can I determine at what point in the frame they actually collided? For instance, two polygon shapes are headed at each other such that, during the 1/60 second timestep, they collide. How can I use the callbacks and the various position/velocity getters bef...
- Fri Nov 20, 2015 1:36 am
- Forum: Support and Development
- Topic: Continuous Collision Detection
- Replies: 4
- Views: 3625
Re: Continuous Collision Detection
So I was going to rewrite my code so that the sphere-sphere worked the same way, but instead decompose sphere-poly and poly-poly collisions into a bunch of line-line collisions. The only thing I thought this method wouldn't handle was where two colliders were coincident (a smaller one inside the oth...
- Thu Nov 19, 2015 8:40 pm
- Forum: Support and Development
- Topic: Continuous Collision Detection
- Replies: 4
- Views: 3625
Continuous Collision Detection
I'm working on a space game with proper physics. This means that ships are moving 10s to 1000s of times their own length each second. To resolve collisions I need a Continuous Collision Detection algorithm. I've implemented the formula seen here, http://studiofreya.com/3d-math-and-physics/little-mor...
- Wed Mar 25, 2015 9:38 pm
- Forum: Support and Development
- Topic: Box2d offset shape from body
- Replies: 2
- Views: 2412
Re: Box2d offset shape from body
Ah, so I see that I have entirely misunderstood the tutorials! So, to clarify, only when using the shortcut to create Rectangles will it be centered upon the body. Otherwise it positions the points that I provide relative to the body. Well that answers a large number of my questions! However, while ...