Default/trees: Add checks for air/ignore/needles to pinetree trunk

Speed optimise: Trunk placing, add_pine_needles, add_snow

mods/default/trees.lua

@@ -74,11 +74,11 @@ local function add_trunk_and_leaves(data, a, pos, tree_cid, leaves_cid,
 	local c_apple = minetest.get_content_id("default:apple")
 
 	-- Trunk
-	for y_dist = 0, height - 1 do
-		local vi = a:index(x, y + y_dist, z)
+	data[a:index(x, y, z)] = tree_cid -- Force-place lowest trunk node to replace sapling
+	for yy = y + 1, y + height - 1 do
+		local vi = a:index(x, yy, z)
 		local node_id = data[vi]
-		if y_dist == 0 or node_id == c_air or node_id == c_ignore
-		or node_id == leaves_cid then
+		if node_id == c_air or node_id == c_ignore or node_id == leaves_cid then
 			data[vi] = tree_cid
 		end
 	end
@@ -209,13 +209,15 @@ end
 -- Pinetree from mg mapgen mod, design by sfan5, pointy top added by paramat
 
 local function add_pine_needles(data, vi, c_air, c_ignore, c_snow, c_pine_needles)
-	if data[vi] == c_air or data[vi] == c_ignore or data[vi] == c_snow then
+	local node_id = data[vi]
+	if node_id == c_air or node_id == c_ignore or node_id == c_snow then
 		data[vi] = c_pine_needles
 	end
 end
 
 local function add_snow(data, vi, c_air, c_ignore, c_snow)
-	if data[vi] == c_air or data[vi] == c_ignore then
+	local node_id = data[vi]
+	if node_id == c_air or node_id == c_ignore then
 		data[vi] = c_snow
 	end
 end
@@ -240,16 +242,14 @@ function default.grow_pine_tree(pos)
 	local a = VoxelArea:new({MinEdge = minp, MaxEdge = maxp})
 	local data = vm:get_data()
 
-	-- Scan for snow nodes near sapling
+	-- Scan for snow nodes near sapling to enable snow on branches
 	local snow = false
 	for yy = y - 1, y + 1 do
 	for zz = z - 1, z + 1 do
 		local vi  = a:index(x - 1, yy, zz)
 		for xx = x - 1, x + 1 do
 			local nodid = data[vi]
-			if nodid == c_snow
-			or nodid == c_snowblock
-			or nodid == c_dirtsnow then
+			if nodid == c_snow or nodid == c_snowblock or nodid == c_dirtsnow then
 				snow = true
 			end
 			vi  = vi + 1
@@ -266,7 +266,7 @@ function default.grow_pine_tree(pos)
 			for xx = x - dev, x + dev do
 				if random() < 0.95 - dev * 0.05 then
 					add_pine_needles(data, vi, c_air, c_ignore, c_snow,
-							c_pine_needles)
+						c_pine_needles)
 					if snow then
 						add_snow(data, via, c_air, c_ignore, c_snow)
 					end
@@ -280,9 +280,9 @@ function default.grow_pine_tree(pos)
 
 	-- Centre top nodes
 	add_pine_needles(data, a:index(x, maxy + 1, z), c_air, c_ignore, c_snow,
-			c_pine_needles)
+		c_pine_needles)
 	add_pine_needles(data, a:index(x, maxy + 2, z), c_air, c_ignore, c_snow,
-			c_pine_needles) -- Paramat added a pointy top node
+		c_pine_needles) -- Paramat added a pointy top node
 	if snow then
 		add_snow(data, a:index(x, maxy + 3, z), c_air, c_ignore, c_snow)
 	end
@@ -301,7 +301,7 @@ function default.grow_pine_tree(pos)
 			local via = a:index(xi, yy + 1, zz)
 			for xx = xi, xi + 1 do
 				add_pine_needles(data, vi, c_air, c_ignore, c_snow,
-						c_pine_needles)
+					c_pine_needles)
 				if snow then
 					add_snow(data, via, c_air, c_ignore, c_snow)
 				end
@@ -319,7 +319,7 @@ function default.grow_pine_tree(pos)
 			for xx = x - dev, x + dev do
 				if random() < 0.95 - dev * 0.05 then
 					add_pine_needles(data, vi, c_air, c_ignore, c_snow,
-							c_pine_needles)
+						c_pine_needles)
 					if snow then
 						add_snow(data, via, c_air, c_ignore, c_snow)
 					end
@@ -332,9 +332,13 @@ function default.grow_pine_tree(pos)
 	end
 
 	-- Trunk
-	for yy = y, maxy do
+	data[a:index(x, y, z)] = c_pinetree -- Force-place lowest trunk node to replace sapling
+	for yy = y + 1, maxy do
 		local vi = a:index(x, yy, z)
-		data[vi] = c_pinetree
+		local node_id = data[vi]
+		if node_id == c_air or node_id == c_ignore or node_id == c_pine_needles then
+			data[vi] = c_pinetree
+		end
 	end
 
 	vm:set_data(data)