Add particle effects for chest unlock

mods/lzr_laser/blocks.lua

@@ -103,12 +103,17 @@ end
 
 function lzr_laser.unlock_chests(min, max)
 	local closed_chests = minetest.find_nodes_in_area(min, max, {"group:chest_closed"})
+	local detectors = minetest.find_nodes_in_area(min, max, {"group:detector"})
 	for c=1, #closed_chests do
-		local pos = closed_chests[c]
-		local node = minetest.get_node(pos)
+		local cpos = closed_chests[c]
+		local node = minetest.get_node(cpos)
 		local def = minetest.registered_nodes[node.name]
 		if def._lzr_unlock then
-			def._lzr_unlock(pos, node)
+			def._lzr_unlock(cpos, node)
+			for d=1, #detectors do
+				local dpos = detectors[d]
+				lzr_laser.particle_line(dpos, cpos, "lzr_laser_particle_trigger.png")
+			end
 		end
 	end
 end

mods/lzr_laser/util.lua

@@ -98,3 +98,31 @@ function lzr_laser.bitwise_or(bin1, bin2)
 	end
 	return out
 end
+
+-- Generates a line of particles between `pos1` and `pos2` with particle texture `particle`
+function lzr_laser.particle_line(pos1, pos2, particle)
+	local steps = 30
+	local amount = 10
+	local spread = 0.1
+	local vspread = 0.01
+	local size = 0.4
+	local pos = vector.copy(pos1)
+	for i=0,steps-1 do
+		pos.x = pos1.x + (pos2.x - pos1.x) * (i/steps)
+		pos.y = pos1.y + (pos2.y - pos1.y) * (i/steps)
+		pos.z = pos1.z + (pos2.z - pos1.z) * (i/steps)
+		minetest.add_particlespawner({
+			amount = amount,
+			time = 0.001,
+			minpos = vector.subtract(pos, vector.new(spread, spread, spread)),
+			maxpos = vector.add(pos, vector.new(spread, spread, spread)),
+			minvel = vector.new(-vspread, -vspread, -vspread),
+			maxvel = vector.new(vspread, vspread, vspread),
+			minsize = size,
+			maxsize = size,
+			texture = particle,
+			minexptime = 1.5,
+			maxexptime = 1.7,
+		})
+	end
+end

mods/lzr_treasure/init.lua

@@ -51,8 +51,45 @@ local register_chest = function(id, def)
 		end,
 		-- Unlock chest
 		_lzr_unlock = function(pos, node)
-			minetest.sound_play({name=sound_lock_break, gain=0.8}, {pos=pos}, true)
 			minetest.set_node(pos, {name="lzr_treasure:chest_"..id.."_unlocked", param2=node.param2})
+
+			minetest.sound_play({name=sound_lock_break, gain=0.8}, {pos=pos}, true)
+
+			local dir = minetest.facedir_to_dir(node.param2)
+			local w = 3/16
+			local k = 9/16
+			local l = 8/16
+			local minoff, maxoff
+			if dir.x > 0 then
+				minoff = vector.new(-k, -w, -w)
+				maxoff = vector.new(-l, w, w)
+			elseif dir.x < 0 then
+				minoff = vector.new(l, -w, -w)
+				maxoff = vector.new(k, w, w)
+			elseif dir.z > 0 then
+				minoff = vector.new(-w, -w, -k)
+				maxoff = vector.new(w, w, -l)
+			elseif dir.z < 0 then
+				minoff = vector.new(-w, -w, l)
+				maxoff = vector.new(w, w, k)
+			end
+			if minoff then
+				minetest.add_particlespawner({
+					amount = 12,
+					time = 0.001,
+					minpos = vector.add(pos, minoff),
+					maxpos = vector.add(pos, maxoff),
+					minvel = vector.new(-0.5, -0.2, -0.5),
+					maxvel = vector.new(0.5, 0.5, 0.5),
+					minacc = vector.new(0, -lzr_globals.GRAVITY, 0),
+					maxacc = vector.new(0, -lzr_globals.GRAVITY, 0),
+					minsize = 0.5,
+					maxsize = 0.5,
+					minexptime = 0.60,
+					maxexptime = 0.65,
+					texture = "lzr_treasure_particle_lock.png",
+				})
+			end
 		end,
 	})