Initial galaxy creation loop. Space skybox in ignore nodes

README.txt

@@ -1,4 +1,4 @@
-planets 0.1.2 by paramat
+planets 0.1.3 by paramat
 For Minetest 0.4.13 and later
 Depends default
 Licenses: code WTFPL

init.lua

@@ -1,5 +1,8 @@
 -- Parameters
 
+local pnum = 1 -- number of planets desired
+local maxatt = 128 -- maximum number of attempts to add a planet
+
 local np_terrain = {
 	offset = 0,
 	scale = 1.0,
@@ -27,10 +30,10 @@ dofile(minetest.get_modpath("planets") .. "/nodes.lua")
 -- Mapgen parameters
 
 minetest.set_mapgen_params({mgname = "singlenode",
-	flags = "nolight", water_level = -31000})
+	chunksize = 5, water_level = -31000, flags = "nolight"})
 
 
--- Space array and planet def table
+-- Create pseudorandom galaxy
 
 -- space is 64 ^ 3 chunks, centred on world centre
 -- space table is flat array of planet ids or nil (vacuum chunk)
@@ -39,41 +42,71 @@ local space = {}
 local def = {}
 local spzstr = 64 * 64 -- space array z stride
 local spystr = 64 -- space array y stride
+local plid = 0 -- planet id of last planet added, 0 = none
+local addatt = 0 -- number of attempts to add a planet
 
+while plid < pnum and addatt <= maxatt do -- avoid infinite attempts
+	-- create initial planet data to check for obstruction
 		-- cenx/y/z is planet centre
 		-- radter = terrain radius / water level
--- radatm = atmosphere radius
--- plavar = planet variation
+		-- radmax = atmosphere radius or max mountain radius
 	local cenx = 0
 	local ceny = 0
 	local cenz = 0
 	local radter = 256
-local radatm = 384
-local plavar = 1
+	local radmax = 384
 
 	-- chunk co-ords of chunk containing planet centre 
 	-- measured from space origin (-32, -32, -32 chunks)
 	local cenxcc = math.floor((cenx + 32) / 80) + 32
 	local cenycc = math.floor((ceny + 32) / 80) + 32
 	local cenzcc = math.floor((cenz + 32) / 80) + 32
-local radatmc = math.ceil(radatm / 80) -- planet radius in chunks
+	local radmaxc = math.ceil(radmax / 80) -- planet radius in chunks
 
--- TODO add similar scan loop to check for existing planets
--- do this once centre and atmosphere radius are known and
--- before calculating other properties or creating def table entry
+	-- check space is clear for planet
+	local clear = true -- is space clear
+	print ("[planets] Checking for obstruction")
 
--- planet 1
-def[1] = {i = cenx, j = ceny, k = cenz, t = radter, a = radatm, v = plavar}
+	for cz = cenzcc - radmaxc, cenzcc + radmaxc do
+		for cy = cenycc - radmaxc, cenycc + radmaxc do
+			local spi = cz * spzstr + cy * spystr + cenxcc - radmaxc + 1
+			for cx = cenxcc - radmaxc, cenxcc + radmaxc do
+				if space[spi] ~= nil then
+					clear = false
+					print ("[planets] Planet obstructed")
+					break
+				end
+				spi = spi + 1
+			end
+			if not clear then
+				break
+			end
+		end
+		if not clear then
+			break
+		end
+	end
 
-for cz = cenzcc - radatmc, cenzcc + radatmc do
-for cy = cenycc - radatmc, cenycc + radatmc do
-	local spi = cz * spzstr + cy * spystr + cenxcc - radatmc + 1
-	for cx = cenxcc - radatmc, cenxcc + radatmc do
-		space[spi] = 1
+	if clear then -- add planet
+		-- TODO generate extra planet data
+		plid = #def + 1 -- planet id
+		-- add planet data to def table
+		def[plid] = {i = cenx, j = ceny, k = cenz, t = radter, m = radmax}
+		print ("[planets] Adding planet " .. plid)
+
+		for cz = cenzcc - radmaxc, cenzcc + radmaxc do
+		for cy = cenycc - radmaxc, cenycc + radmaxc do
+			local spi = cz * spzstr + cy * spystr + cenxcc - radmaxc + 1
+			for cx = cenxcc - radmaxc, cenxcc + radmaxc do
+				space[spi] = plid -- add planet id to this chunk
 				spi = spi + 1
 			end
 		end
 		end
+	end
+
+	addatt = addatt + 1
+end
 
 
 -- Globalstep function
@@ -89,14 +122,15 @@ local skybox_space = {
 
 minetest.register_globalstep(function(dtime)
 	for _, player in ipairs(minetest.get_connected_players()) do
-		if math.random() < 0.02 then -- set gravity, skybox and override light
+		if math.random() < 0.05 then -- set gravity, skybox and override light
 			local ppos = player:getpos()
 			ppos.y = ppos.y + 1.5 -- node player head is in
-			if minetest.get_node(ppos).name == "planets:vacuum" then
+			local nodename = minetest.get_node(ppos).name
+			if nodename == "planets:vacuum" or nodename == "ignore" then -- space
 				--player:set_physics_override(1, 1, 1) -- speed, jump, gravity
 				player:set_sky({r = 0, g = 0, b = 0, a = 0}, "skybox", skybox_space)
 				player:override_day_night_ratio(1)
-			else
+			else -- regular sky for now
 				--player:set_physics_override(1, 1, 1) -- speed, jump, gravity
 				player:set_sky({}, "regular", {})
 				player:override_day_night_ratio(nil)
@@ -165,7 +199,7 @@ minetest.register_on_generated(function(minp, maxp, seed)
 		local nvals_terrain = nobj_terrain:get3dMap_flat(pmapminp, nbuf_terrain)
 		local nvals_cloud   = nobj_cloud:get3dMap_flat(pmapminpclo, nbuf_cloud)
 
-		local tersca = (pdef.a - pdef.t) / 2 -- terrain scale
+		local tersca = (pdef.m - pdef.t) / 2 -- terrain scale
 
 		local ni = 1 -- noise index
 		for z = z0, z1 do
@@ -195,7 +229,7 @@ minetest.register_on_generated(function(minp, maxp, seed)
 					if nvals_cloud[niq] > 0.5 then
 						data[vi] = c_cloud
 					end
-				elseif nodrad <= pdef.a then -- air
+				elseif nodrad <= pdef.m then -- air
 					data[vi] = c_air
 				else -- vacuum
 					data[vi] = c_vacuum
@@ -227,5 +261,5 @@ minetest.register_on_generated(function(minp, maxp, seed)
 	vm:write_to_map(data)
 
 	local chugent = math.ceil((os.clock() - t0) * 1000)
-	print ("[planets] " .. chugent .. " ms")
+	print ("[planets] Generated chunk " .. chugent .. " ms")
 end)