I'm trying to get into the Godot Engine by following the book "Godot Engine Game Development in 24 Hours" from Sams Teach Yourself by A. Manzur and G. Marques.
In Hour 5 there's a sample project "Space Shooter" where several scenes are created. The root nodes are assigned to the scene's group. So the "player" scene has a "player" group.
On the "asteroid" scene a script is applied in which is checked if the asteroid is colliding with the player or a lasershot:
if area.is_in_group("shot") or area.is_in_group("player"):
Now, how do I add the groups of the other scenes? In the group manager the other groups don't show up and if I try to add them manually, by typing their names and pressing add, only the asteroids nodes show.
Also, is "area" an in built constant or do I have to define it?
Like the Sprite-'area' of the "asteroid" scene/node is named "spr_asteroid".