Improve mapgen, add grass, and include the fill tool.

mods/rgt_base/init.lua

@@ -67,6 +67,39 @@ setmetatable(EventTarget, {
     __call = function(_, ...) return EventTarget.init(...) end
 })
 
+StateMachine = {
+    init = function(obj, states)
+        local super = EventTarget()
+        local e = {
+            states = states,
+            active_states = {},
+            obj = obj
+        }
+        return setmetatable(e, {__index = super})
+    end,
+    add_state = function(e, state)
+        if e.active_states[state] then return false end
+        e.states[state]:add(e.obj)
+        e.active_states[state] = true
+        return true
+    end,
+    tick = function(e)
+        for k in pairs(e.active_states) do
+            e.states[k]:tick(e.obj)
+        end
+    end,
+    remove_state = function(e, state)
+        if not e.active_states[state] then return false end
+        e.states[state]:remove(e.obj)
+        e.active_states[state] = nil
+        return true
+    end,
+}
+setmetatable(StateMachine, {
+    __call = function(_, ...) return StateMachine.init(...) end,
+    __index = EventTarget()
+})
+
 rgt = {
     adjacent_neighbor_offests = {
         vector.new(0,0,1),
@@ -85,7 +118,8 @@ rgt = {
         vector.new(-1,0,0),
     },
     nodes_to_content_ids = {},
-    content_ids_to_nodes = {}
+    content_ids_to_nodes = {},
+    vm_data = {},
 }
 local ns = rgt
 
@@ -151,6 +185,60 @@ function ns.register_entity(name, def)
     minetest.register_entity(name, def)
 end
 
+-- Make node dig particles denser.
+minetest.register_on_dignode(function(pos, node, digger)
+    local gravity = tonumber(core.settings:get("movement_gravity")) or 9.81
+    local def = minetest.registered_nodes[node.name]
+    minetest.add_particlespawner({
+        amount = 128,
+        time = 0.001,
+        minpos = vector.offset(pos, -0.35, -0.35, -0.35),
+        maxpos = vector.offset(pos, 0.35, 0.35, 0.35),
+        minvel = vector.new(-1.7, 0, -1.7),
+        maxvel = vector.new(1.7, 3.5, 1.7),
+        minacc = vector.new(0, -gravity *2, 0),
+        maxacc = vector.new(0, -gravity *2, 0),
+        minexptime = 0, maxexptime = 1,
+        minsize = 0, maxsize = 0, -- random
+        node = node,
+        minsize = 0.5,
+        maxsize = 1.4,
+        blend = (def and def.use_texture_alpha == "blend") and "blend" or "clip",
+    })
+end)
+
+-- Fills the area from pos1 to pos2 with the node named `node`.
+function ns.fill_area(pos1, pos2, node)
+    local minp = vector.new(math.min(pos1.x, pos2.x), math.min(pos1.y, pos2.y), math.min(pos1.z, pos2.z))
+    local maxp = vector.new(math.max(pos1.x, pos2.x), math.max(pos1.y, pos2.y), math.max(pos1.z, pos2.z))
+    local vm = minetest.get_voxel_manip(pos1, pos2)
+    local min, max = vm:get_emerged_area()
+    local va = VoxelArea(min, max)
+    local data = ns.vm_data
+        
+    vm:get_data(data)
+    
+    local c_node = minetest.get_content_id(node)
+    for i in va:iterp(minp, maxp) do
+        data[i] = c_node
+    end
+    
+    vm:set_data(data)
+    vm:write_to_map()
+    if vm.close then vm:close() end
+end
+
+-- Get a flat texture that may represent the given node (using the first tile).
+function ns.get_node_texture(node)
+    local def = minetest.registered_nodes[node]
+    if not def or not def.tiles then return "blank.png" end
+    local tx = def.tiles[1]
+    if type(tx) == "string" then
+        return tx
+    end
+    return tx.name or "blank.png"
+end
+
 -- Out-of-line node metadata, allowing meta for a node to be accessed even when its containing mapblock is not loaded.
 local db = minetest.get_mod_storage()
 local NodeMetaRef = {