GetEntityCollisions

From OxeyeWiki

physics:getEntityCollisions(entityId)
Fetches a list of current collision points for a given entity. This list will not include sensor points, they are stored in a separate list and are fetched with getEntitySensorPoints.
Parameter	Expected Type	Description
enitityId	An integer	The entity's body identifier.
Returns
Returns a table containing collision elements (see below). If no collisions are found, this method returns nil to save some garbage collection performance. In other words, the returned table is never empty, it's either nil or non-empty.

Collision Info

The returned table contains a list of collision points. Each point has the following info:

Parameter	Type	Description
x	A number	The world X position of the collision point, measured in meters.
y	A number	The world Y position of the collision point, measured in meters.
nx	A number	The collision point normal's normalized X value. Points towards the entity.
ny	A number	The collision point normal's normalized Y value. Points towards the entity.
impulse	A number	The collision impulse.
id	An integer	The entity identifier of the body that this entity has collided with.
userData	A string	If the other entity has userData in the shape that this entity has collided with, that userData will be copied to this value. This is usually nil. See Common Shape Settings.

Example

   local collisions = physics:getEntityCollisions(player.body)
   if collisions then
      for index, info in ipairs(collisions) do
          local userData = info.userData or "n/a"
          print("Collision with ".. info.id .. " at (" .. info.x .. ", " .. info.y .. "), (" ..
             info.nx .. ", " .. info.ny .. "), " .. info.impulse .. ", " userData)
      end
   end