//convolve: update matrix & kernel to use Vector3

A lot of the maths remains in the old style, but at least it doesn't 
take a zero-indexed table

worldeditadditions/lib/conv/conv.lua

@@ -1,3 +1,5 @@
+local Vector3 = worldeditadditions.Vector3
+
 worldeditadditions.conv = {}
 
 dofile(worldeditadditions.modpath.."/lib/conv/kernels.lua")
@@ -41,14 +43,16 @@ end
 function worldeditadditions.convolve(pos1, pos2, kernel, kernel_size)
 	pos1, pos2 = worldedit.sort_pos(pos1, pos2)
 	
-	local border_size = {}
-	border_size[0] = (kernel_size[0]-1) / 2		-- height
-	border_size[1] = (kernel_size[1]-1) / 2		-- width
+	local border_size = Vector3.new(
+		(kernel_size.x-1) / 2,		-- x = height
+		0,
+		(kernel_size.z-1) / 2		-- z = width
+	)
 	
-	pos1.z = pos1.z - border_size[0]
-	pos2.z = pos2.z + border_size[0]
-	pos1.x = pos1.x - border_size[1]
-	pos2.x = pos2.x + border_size[1]
+	pos1.z = pos1.z - border_size.x
+	pos2.z = pos2.z + border_size.x
+	pos1.x = pos1.x - border_size.z
+	pos2.x = pos2.x + border_size.z
 	
 	local manip, area = worldedit.manip_helpers.init(pos1, pos2)
 	local data = manip:get_data()

worldeditadditions/lib/conv/convolve.lua

@@ -1,31 +1,39 @@
-
+local wea = worldeditadditions
+local Vector3 = wea.Vector3
 --[[
 Convolves over a given 2D heightmap with a given matrix.
 Note that this *mutates* the given heightmap.
 Note also that the dimensions of the matrix must *only* be odd.
-@param	{number[]}			heightmap		The 2D heightmap to convolve over.
-@param	{[number,number]}	heightmap_size	The size of the heightmap as [ height, width ]
-@param	{number[]}			matrix			The matrix to convolve with.
-@param	{[number, number]}	matrix_size		The size of the convolution matrix as [ height, width ]
+@param	{number[]}	heightmap		The 2D heightmap to convolve over.
+@param	Vector3		heightmap_size	The size of the heightmap as an X/Z Vector3 instance.
+@param	{number[]}	matrix			The matrix to convolve with.
+@param	Vector3		matrix_size		The size of the convolution matrix as an X/Z Vector3 instance.
 ]]--
 function worldeditadditions.conv.convolve(heightmap, heightmap_size, matrix, matrix_size)
-	if matrix_size[0] % 2 ~= 1 or matrix_size[1] % 2 ~= 1 then
+	if matrix_size.x % 2 ~= 1 or matrix_size.z % 2 ~= 1 then
 		return false, "Error: The matrix size must contain only odd numbers (even number detected)"
 	end
 	
-	local border_size = {}
-	border_size[0] = (matrix_size[0]-1) / 2		-- height
-	border_size[1] = (matrix_size[1]-1) / 2		-- width
-	-- print("[convolve] matrix_size", matrix_size[0], matrix_size[1])
-	-- print("[convolve] border_size", border_size[0], border_size[1])
+	-- We need to reference a *copy* of the heightmap when convolving
+	-- This is because we need the original values when we perform a
+	-- convolution on a given pixel
+	local heightmap_copy = wea.table.shallowcopy(heightmap)
+	
+	local border_size = Vector3.new(
+		(matrix_size.x-1) / 2,		-- x = height
+		0,
+		(matrix_size.z-1) / 2		-- z = width
+	)
+	-- print("[convolve] matrix_size", matrix_size.x, matrix_size.z)
+	-- print("[convolve] border_size", border_size.x, border_size.z)
 	-- print("[convolve] heightmap_size: ", heightmap_size.z, heightmap_size.x)
 	-- 
-	-- print("[convolve] z: from", (heightmap_size.z-border_size[0]) - 1, "to", border_size[0], "step", -1)
-	-- print("[convolve] x: from", (heightmap_size.x-border_size[1]) - 1, "to", border_size[1], "step", -1)
+	-- print("[convolve] z: from", (heightmap_size.z-border_size.x) - 1, "to", border_size.x, "step", -1)
+	-- print("[convolve] x: from", (heightmap_size.x-border_size.z) - 1, "to", border_size.z, "step", -1)
 	
 	-- Convolve over only the bit that allows us to use the full convolution matrix
-	for z = (heightmap_size.z-border_size[0]) - 1, border_size[0], -1 do
-		for x = (heightmap_size.x-border_size[1]) - 1, border_size[1], -1 do
+	for z = (heightmap_size.z-border_size.x) - 1, border_size.x, -1 do
+		for x = (heightmap_size.x-border_size.z) - 1, border_size.z, -1 do
 			local total = 0
 			
 			
@@ -33,21 +41,22 @@ function worldeditadditions.conv.convolve(heightmap, heightmap_size, matrix, mat
 			-- print("[convolve/internal] z", z, "x", x, "hi", hi)
 			
 			-- No continue statement in Lua :-/
-			if heightmap[hi] ~= -1 then
-				for mz = matrix_size[0]-1, 0, -1 do
-					for mx = matrix_size[1]-1, 0, -1 do
-						local mi = (mz * matrix_size[1]) + mx
-						local cz = z + (mz - border_size[0])
-						local cx = x + (mx - border_size[1])
+			if heightmap_copy[hi] ~= -1 then
+				for mz = matrix_size.x-1, 0, -1 do
+					for mx = matrix_size.z-1, 0, -1 do
+						local mi = (mz * matrix_size.z) + mx
+						local cz = z + (mz - border_size.x)
+						local cx = x + (mx - border_size.z)
 						
 						local i = (cz * heightmap_size.x) + cx
 						
 						-- A value of -1 = nothing in this column (so we should ignore it)
-						if heightmap[i] ~= -1 then
-							total = total + (matrix[mi] * heightmap[i])
+						if heightmap_copy[i] ~= -1 then
+							total = total + (matrix[mi] * heightmap_copy[i])
 						end
 					end
 				end
+				
 				-- Rounding hack - ref https://stackoverflow.com/a/18313481/1460422
 				-- heightmap[hi] = math.floor(total + 0.5)
 				heightmap[hi] = math.ceil(total)

worldeditadditions/lib/erode/snowballs.lua

@@ -1,3 +1,4 @@
+local Vector3 = worldeditadditions.Vector3
 
 -- Test command: //multi //fp set1 1313 6 5540 //fp set2 1338 17 5521 //erode snowballs
 
@@ -132,7 +133,7 @@ function worldeditadditions.erode.snowballs(heightmap_initial, heightmap, height
 	if not params.noconv then
 		local success, matrix = worldeditadditions.get_conv_kernel("gaussian", 3, 3)
 		if not success then return success, matrix end
-		local matrix_size = {} matrix_size[0] = 3 matrix_size[1] = 3
+		local matrix_size = Vector3.new(3, 0, 3)
 		worldeditadditions.conv.convolve(
 			heightmap, heightmap_size,
 			matrix,

worldeditadditions_commands/commands/convolve.lua

@@ -1,3 +1,6 @@
+local wea = worldeditadditions
+local Vector3 = wea.Vector3
+
 --  ██████  ██████  ███    ██ ██    ██  ██████  ██     ██    ██ ███████
 -- ██      ██    ██ ████   ██ ██    ██ ██    ██ ██     ██    ██ ██
 -- ██      ██    ██ ██ ██  ██ ██    ██ ██    ██ ██     ██    ██ █████
@@ -11,8 +14,8 @@ worldedit.register_command("convolve", {
 	parse = function(params_text)
 		if not params_text then params_text = "" end
 		
-		-- local parts = worldeditadditions.split(params_text, "%s+", false)
-		local parts = worldeditadditions.split_shell(params_text)
+		-- local parts = wea.split(params_text, "%s+", false)
+		local parts = wea.split_shell(params_text)
 		
 		local kernel_name = "gaussian"
 		local width = 5
@@ -23,7 +26,7 @@ worldedit.register_command("convolve", {
 			kernel_name = parts[1]
 		end
 		if #parts >= 2 then
-			local parts_dimension = worldeditadditions.split(parts[2], ",%s*", false)
+			local parts_dimension = wea.split(parts[2], ",%s*", false)
 			width = tonumber(parts_dimension[1])
 			if not width then
 				return false, "Error: Invalid width (it must be a positive odd integer)."
@@ -50,26 +53,33 @@ worldedit.register_command("convolve", {
 		return worldedit.volume(worldedit.pos1[name], worldedit.pos2[name])
 	end,
 	func = function(name, kernel_name, kernel_width, kernel_height, sigma)
-		local start_time = worldeditadditions.get_ms_time()
+		local start_time = wea.get_ms_time()
 		
-		local success, kernel = worldeditadditions.get_conv_kernel(kernel_name, kernel_width, kernel_height, sigma)
+		local success, kernel = wea.get_conv_kernel(kernel_name, kernel_width, kernel_height, sigma)
 		if not success then return success, kernel end
 		
-		local kernel_size = {}
-		kernel_size[0] = kernel_height
-		kernel_size[1] = kernel_width
+		local kernel_size = Vector3.new(
+			kernel_height,
+			0,
+			kernel_width
+		)
+		
+		local pos1, pos2 = Vector3.sort(
+			worldedit.pos1[name],
+			worldedit.pos2[name]
+		)
 		
 		local stats
-		success, stats = worldeditadditions.convolve(
-			worldedit.pos1[name], worldedit.pos2[name],
+		success, stats = wea.convolve(
+			pos1, pos2,
 			kernel, kernel_size
 		)
 		if not success then return success, stats end
 		
-		local time_taken = worldeditadditions.get_ms_time() - start_time
+		local time_taken = wea.get_ms_time() - start_time
 		
 		
-		minetest.log("action", name.." used //convolve at "..worldeditadditions.vector.tostring(worldedit.pos1[name]).." - "..worldeditadditions.vector.tostring(worldedit.pos2[name])..", adding "..stats.added.." nodes and removing "..stats.removed.." nodes in "..time_taken.."s")
-		return true, "Added "..stats.added.." and removed "..stats.removed.." nodes in " .. worldeditadditions.format.human_time(time_taken)
+		minetest.log("action", name.." used //convolve at "..pos1.." - "..pos2..", adding "..stats.added.." nodes and removing "..stats.removed.." nodes in "..time_taken.."s")
+		return true, "Added "..stats.added.." and removed "..stats.removed.." nodes in " .. wea.format.human_time(time_taken)
 	end
 })