B2.Contact
From GiderosMobile
Supported platforms: 
Available since: Gideros 2012.09.6
Description
The class manages contact between two shapes. A contact exists for each overlapping AABB in the broad-phase (except if filtered). Therefore a contact object may exist that has no contact points.
Examples
Checking collisions from bottom using b2.Contact
local isTouchingGround = false
world:addEventListener(Event.BEGIN_CONTACT, function(e)
local manifold = e.contact:getWorldManifold()
if manifold.normal.y > 0.9 then
--collision came from bottom
isTouchingGround = true
end
end)
world:addEventListener(Event.END_CONTACT, function(e)
local manifold = e.contact:getWorldManifold()
if manifold.normal.y < 0.1 then
--collision ended from bottom
isTouchingGround = false
end
end)
