Add experimental particle-based water drips system

init.lua

@@ -3,7 +3,7 @@ pedology.wetnames = {[0] = "dry",  "wet", "watery", "sludgy", "muddy", "slurry"
 
 dofile(minetest.get_modpath("pedology").."/settings.lua")
 
-if pedology.USE_DRIPS == true then
+if pedology.USE_DRIPS == 1 then
 	dofile(minetest.get_modpath("pedology").."/drip.lua")
 end
 
@@ -242,6 +242,43 @@ pedology.register_liquid("lava_3", "lava",		230, 4,  8, 6, {a=230, r=255, g=0, b
 pedology.register_liquid("lava_4", "cold lava",		230, 5,  7, 6, {a=230, r=255, g=0, b=0}, {hot=3000, lava=1})
 ]]
 
+--[[ Water drip function ]]
+function pedology.drip_particle(pos, wet)
+	local below1 = minetest.get_node({x=pos.x, y=pos.y-1, z=pos.z})
+	local below2 = minetest.get_node({x=pos.x, y=pos.y-2, z=pos.z})
+	if(below1.name == "air" and below2.name == "air") then
+		return minetest.add_particlespawner(
+			wet,	-- amount
+			0,	-- time
+			{ x=pos.x -(45/100), y=pos.y - 0.5, z=pos.z -(45/100) },	-- minpos
+			{ x=pos.x +(45/100), y=pos.y - 0.5, z=pos.z +(45/100) },	-- maxpos
+			{ x=0, y=-9.80, z=0 }, { x=0, y=0, z=0 }, -- minvel, maxvel
+			{ x=0, y=-9.82, z=0 }, { x=0, y=0, z=0 }, -- minacc, maxacc
+			1, 3, -- minexptime, maxexptime
+			1, 1, -- minsize, maxsize
+			false, -- collisiondetection
+			"pedology_water_fresh.png" -- texture
+			-- playername
+		--[[ For future Lua API
+		{
+			amount = wet,
+			time = 0,
+			minpos = { pos.x -(45/100), pos.y - 0.5, pos.z -(45/100) },
+			maxpos = { pos.x +(45/100), pos.y - 0.5, pos.z +(45/100) },
+			minvel = { 0, -9.81, 0 },
+			maxvel = { 0, 0, 0 },
+			minexptime = 1,
+			maxexptime = 3,
+			collisiondetection = true,
+			vertical = true,
+			texture = "pedology_water_fresh.png",
+		}]]
+)
+	else
+		return nil
+	end
+end
+ 
 --[[ register a sucky/oozing node to this mod ]]
 function pedology.register_sucky(basename, description, wetness, oozing, sucky, melting_point, drop, sounds, additional_groups)
 	local wetname = basename.."_"..tostring(wetness)
@@ -258,6 +295,24 @@ function pedology.register_sucky(basename, description, wetness, oozing, sucky,
 
 	-- If the node is not dry, do not add it into the creative inventory
 	if wetness == 0 then noncreative = 0 else noncreative = 1 end
+	if pedology.USE_DRIPS == 2 then
+		on_construct = function(pos)
+			local dripper = pedology.drip_particle(pos, wetness)
+			if(dripper ~= nil) then
+				local meta = minetest.get_meta(pos)
+				meta:set_int("dripper", dripper)
+			end
+		end
+		on_destruct = function(pos)
+			local meta = minetest.get_meta(pos)
+			local dripper = meta:get_int("dripper")
+			if(dripper ~= nil) then
+				minetest.delete_particlespawner(dripper)
+			end
+		end
+	else
+		on_construct, after_destruct = nil
+	end
 	local nodedef = {
 		description = description,
 		inventory_image = minetest.inventorycube("pedology_"..wetname..".png"),
@@ -267,9 +322,13 @@ function pedology.register_sucky(basename, description, wetness, oozing, sucky,
 		groups = groups,
 		sounds = sounds,
 		is_ground_content = true,
+		on_construct = on_construct,
+		on_destruct = on_destruct,
 	}
 	minetest.register_node(name, nodedef)
 
+
+
 end
 
 
@@ -335,7 +394,7 @@ function pedology.register_sucky_group(basename, basedescription, lumpbasedescri
 		end
 		pedology.register_sucky(basename, (pedology.wetnames[w]).." "..basedescription, w, oozing, sucky, m, drop, sounds, groups)
 		-- register dripping
-		if(w>0 and pedology.USE_DRIPS == true) then
+		if(w>0 and pedology.USE_DRIPS == 1) then
 			minetest.register_abm({
 				nodenames = {"pedology:"..basename.."_"..tostring(w)},
 				neighbors = {"air"},

settings.lua

@@ -1,5 +1,8 @@
--- Create water drips. Warning: This feature is experimental and there are performance issues with it.
-pedology.USE_DRIPS = false
+--[[ Create water drips. This is still an experimental feature
+ 0 = don’t use water drips
+ 1 = use entity-based water drips (3D, with sounds, slow)
+ 2 = use particle-based water drips (2D, without sounds, fast) ]]
+pedology.USE_DRIPS = 0
 
 -- Minimum light level at which nodes dry out from light
 pedology.DRY_LIGHT = 13