physic object collision detection ?

[PGUp]

i read some docs about it.. but im not really understand it.. is it possible to check collision from the object physics shape ? please make it simple

[erasio]

Collision events are handled by the world.

You can set callback events which provide you with a reference to the fixture of both colliding elements and a contact object which has some more data.

Via the fixture you can access the shape. You can also supply userdata to the fixture to have a reference to a custom table (for example a custom class of yours) if you need that data. Via which you could call a function that all your physics objects have but handle things differently on a per object basis.

Take a look at this tutorial if you haven't already:

https://love2d.org/wiki/Tutorial:Physic ... nCallbacks

[PGUp]

thanks !

[Pospos]

i have a kinda more likely to work way to handle collision beacause i've tried this tutorial, and it havent been very successful to me.

i used few variables

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up = 0
left = 0
right = 0
down = 0

i added the collisions of a player by adding it's position.

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	player.x = 100
	player.y = 200

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shape.x = 300
shape.y = 300
shape.wid = 32
shape.hei = 32

then i added this function

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function CheckCollision(x1,y1,w1,h1, x2,y2,w2,h2)--
 local bx1,by1,bx2, by2 = x1 + w1 ,y1 + h1, x2 + w2, y2 + h2
 return x1 < x2+w2 and
   x2 < x1+w1 and
    y1 < y2+h2 and
    y2 < y1+h1
end 

and finally i implemented 4 lines that composed a collision rectangle for the player.

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    if CheckCollision (player.x + 19, player.y + 13, 20, 1, shape.x, shape.y, shape.wid ,shape.hei)then 
    -- the first four values correspond to the first shape, the other fours the second shape.
      up = 1
    else
     up = 0
    end
    if CheckCollision (player.x + 17, player.y + 14, 1, 20, shape.x, shape.y, shape.wid ,shape.hei)then
      left = 1 
     else 
      left = 0
    end
    if CheckCollision (player.x + 40, player.y + 14, 1, 20, shape.x, shape.y,shape.wid, shape.hei)then
     else
     right = 0
    end
if CheckCollision (player.x + 19, player.y + 35, 20, 1, shape.x, shape.y, shape.wid ,shape.hei)then
      down = 1 
    else
      down = 0

EDIT : you can put anything you want in those CheckCollision events
and everything you put will be encountered only when colliding from the direction you set

exemple :

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if CheckCollision (player.x + 19, player.y + 35, 20, 1, shape.x, shape.y, shape.wid ,shape.hei)then
      down = 1 
     a= a + 1
    else
      down = 0

then a will be incremented by 1 only when colliding to the down.