how do you get one property from a tuple?

Game Engine Game Engine Support and Discussion
1

i am using rayCast to find if there is a roof over my character’s head, but it only returns a tuple thing, and i can’t use rayCastTo, because it stops at one object.
all i want is the name of the object that it returns, how do i get rid of the other parts of the property?
any help would be greatly appreciated.

2

use [0] to get the first item.
so:

ray_object = obj.rayCast( cube, obj, 0.0, “blueTeam”, 1, 1, 0)[0]

or you can do:

ray = obj.rayCast( cube, obj, 0.0, “blueTeam”, 1, 1, 0)
ray_object = ray[0]

use [1] for the second thing etc…

ray_hit_point = ray[1]

You can find a list of the things returned by raycast here:
http://www.tutorialsforblender3d.com/GameModule/ClassKX_GameObject_21.html

so:
Returns the game object[0], the hit point[1] and hit normal[2] (poly = 0)
or
Returns the game object[0], the hit point[1], hit normal[2] and polygon[3] (poly = 1)

3

thanks heaps

4

I’ve also found that a star operator is useful for unpacking an entire tuple in one step:


ray = obj.rayCast( cube, obj, 0.0, "blueTeam", 1, 1, 0)
ray_object, ray_hit, ray_normal = *ray

See:
http://docs.python.org/tutorial/controlflow.html#unpacking-argument-lists

Edit:
Oops… this does not work. :S

5

It doesn’t work because you put a star in there. The line should read

ray_object, ray_hit, ray_normal = ray