Interacting

One final problem with your nodes is that, as they stand, they are unbreakable. This means that, once you lay them down, you can't pick them up again or bash them until they smash. They are indestructible.

You can make nodes destructible by adding the groups directive to the nodes table. A line that would make our reinforced steel crack and break after three or four consecutive blows with a pickax would be:

groups = {cracky = 3},

The groups directive tells the Minetest engine how the node is destroyed [11]. Hard objects, like stone and bricks, crack, so they belong to the cracky group. Softer objects, like dirt or sand, belong to the crumbly group. There are a wide variety of groups that cover flammability, wetness, liquid porosity, and so on.

The value assigned to the group tells Minetest how resistant the node is. The higher the value, the harder it is to break. As it stands, the so-called "reinforced" steel is pretty weak and cracks and breaks easily. You may want to increase that 3 to something higher.

Your final mod will look like Listing 6.

minetest.register_node ("personal:reinforced_steel", {
 tiles = {"reinforced.png"},
 groups = {cracky = 3},
 drawtype = "nodebox",
 node_box = {
  type = "fixed",
  fixed = {{-0.5, -0.5, -0.5, 0.5, -0.3, 0.5}},
 }
})
minetest.register_node ("personal:safe", {
 tiles = {
  "reinforced.png",
  "reinforced.png",
  "reinforced.png",
  "reinforced.png",
  "reinforced.png",
  "reinforced.png^safe_front.png"
 }
})
minetest.register_craft ({
 output = "personal:safe",
 recipe = {
   {"personal:reinforced_steel", "personal:reinforced_steel", "personal:reinforced_steel"},
   {"personal:reinforced_steel", "", "personal:reinforced_steel"},
   {"personal:reinforced_steel", "personal:reinforced_steel", "personal:reinforced_steel"}
 }
})

Conclusion

This article has only just scratched the surface of mod making for Minetest. You can interact with your nodes in many other ways. You have a whole slew of events you can trigger when you punch, dig, use, or right-click an object in your world. You could, for example, make your safe very, very resistant to digging, but, when right-clicked, it will ask players for a combination that will allow them to open the safe.

Minetest's possibilities are pretty much endless, and the modding community is thriving. Players and developers from all over the world are creating mods that help turn Minetest worlds into role playing games, educational environments, places where visitors can express their creativity, and so much more.

Minetest is a cracking good game in its own right, and its mod system offers a whole new level of control and flexibility that you won't find in the alternatives.