LÖVE

• -Object Oriented-ness (e.g - b = World:newBody(...) -> b:newRectangleShape(...)
  -Drawing Shapes/Joints for quick prototyping
  -Collision handling (Of which im stuck on, But have a concept for whomever can help me implement it)

local b = fizz.newBody(...)
b:newRectangleShape(...)
b:setMassFromShapes()

local b2 = fizz.newBody(...)
b2:newRectangleShape(...)

if b:isColliding() then
     local otherBody = b:getCollidingBody()               --Returns the body colliding with b
     local myCollidingShape = b:getCollidingShape()              --Returns the shape on b that collided
     local otherBodyCollidingShape = otherBody:getCollidingShape()           --Returns the otherBody's shape that collided
end

mikembley wrote:Ok, So im in the progress of making a library, with the focus of making physics module a bit easier to use, or harder depending on which way you would prefer to use it.

But first off, i would like to say that my programming skill is somewhat shitty ( making stuff work, but doesnt look neat ) so my code is ugly looking in places, and is probably inefficient to say the least, which is of course why i am posting now, to get some sound and expert advice

Features:

• -Object Oriented-ness (e.g - b = World:newBody(...) -> b:newRectangleShape(...)
  -Drawing Shapes/Joints for quick prototyping
  -Collision handling (Of which im stuck on, But have a concept for whomever can help me implement it)

Ive uploaded a demo of my project, but unfortunately it will crash, due to the fact that i dont understand why contact:getPosition() seems to crash LÖVE.
And this is mainly why i am posting, as a cry for help.

I am trying to use world:setCallbacks() to add/update/remove the bodies/shapes collision data to themselves. Like i envision in this code:
Which i have now implemented with 3 methods

Code: Select all

local b = fizz.newBody(...)
b:newRectangleShape(...)
b:setMassFromShapes()

local b2 = fizz.newBody(...)
b2:newRectangleShape(...)

if b:isColliding() then
     local otherBody = b:getCollidingBody()               --Returns the body colliding with b
     local myCollidingShape = b:getCollidingShape()              --Returns the shape on b that collided
     local otherBodyCollidingShape = otherBody:getCollidingShape()           --Returns the otherBody's shape that collided
end

It sort of works, but its temperamental, i would guess this issue is possibly the same as this: (http://love2d.org/wiki/Remove_Workaround)
The offending code starts at line 576 of fizzlib.lua

My erratic bug seems to be an issue with a vector lib that i borrowed, some sort of math bug, i havent located it yet, but the area that causes it is the car drawing code.

Also constructive criticism is welcome as well, such as structure and layout of code.

The controls for the little demo:

Left/Right Arrow keys = Rotate Car
Up/Down Arrow Keys = Accelerate/Reverse Car
A / D = Move little character left and right
1 = Turn on crashing contact bug
2 = Toggle Drawing Car and Character images

Sidenote: Ignore the dodgy references in other files i took the LÖVE naming convention a bit too far

Updated:

fizzlib_fixed2.love

Older Version:

fizzlib.love

ivan wrote: A body may collide with several other bodies in the same frame so keep that in mind.

ivan wrote: Also, you are creating a new table for each new collision just to overwrite the old collision table which is not very efficient.

ivan wrote: "bodyAtPoint(x, y)" there could be several bodies occupying the same point if they have sensor shapes, for example.

ivan wrote: Wouldn't it be nice to be able to create and lookup bodies by ID/name?
How about a world:findbody ( id ) function?

I agree, Although i am not really interested in this part yet

ivan wrote: A vector class (like b2Vec2) sounds like a neat idea but it's a burden on the Lua GC in my experience.

I was only using a vector class to draw a suspension onto my Car.

ivan wrote: Lastly, don't forget that when destroying a body, you also have to destroy and clear all associated joints.

mikembley wrote:And this, may be a possible reason why it was crashing in the first place, although i am unsure. What would be the best way? reuse the old table and remove the expired contacts?

ivan wrote:The only problem with this method is that it doesn't store the actual position of contact.