Encode map in treasure map style

init.lua

@@ -77,18 +77,10 @@ maps.create_map = function(pos, player_name)
 
 		local pixels = {}
 		local colormap = {
-			{   0,   0,   0 },
-			{   0,   0, 255 }, -- water
-			{ 255, 127,   0 }, -- lava
-			{ 127, 127, 127 }, -- cracky
-			{ 175, 175, 175 }, -- crumbly
-			{  47,  47,  47 }, -- stone
-			{ 127,  47,  47 }, -- soil
-			{   0, 255,   0 }, -- grass
-			{ 255, 255,   0 }, -- sand
-			{ 255, 255, 255 }, -- snow
-			{   0,  47,   0 }, -- leaves
-			{ 255,   0,   0 }, -- fire
+			{ 195, 175, 140 }, -- background
+			{  60,  35,  16 }, -- dark line
+			{ 135,  90,  40 }, -- liquid dark
+			{ 210, 170, 130 }, -- liquid light
 		}
 		for x = 1,size,1 do
 			for z = 1,size,1 do
@@ -98,25 +90,44 @@ maps.create_map = function(pos, player_name)
 			end
 		end
 
-		local color_map = function(color, query)
-			local positions = minetest.find_nodes_in_area_under_air(minp, maxp, query)
+		local positions = minetest.find_nodes_in_area_under_air(
+			minp,
+			maxp,
+			"group:liquid"
+		)
 		for _, p in ipairs(positions) do
 			local z = p.z - minp.z + 1
 			local x = p.x - minp.x + 1
-				pixels[z][x] = { color }
+			pixels[z][x] = { 2 }
+		end
+
+		-- draw coastline
+		for x = 1,size,1 do
+			for z = 1,size,1 do
+				if (
+					pixels[z][x][1] == 2 or
+					pixels[z][x][1] == 3
+				) then
+					pixels[z][x] = { 2 + z % 2 } -- stripes
+					if z > 1 and pixels[z-1][x][1] < 2 then
+						pixels[z-1][x] = { 1 }
+						pixels[z][x] = { 2 }
+					end
+					if z < size and pixels[z+1][x][1] < 2 then
+						pixels[z+1][x] = { 1 }
+						pixels[z][x] = { 2 }
+					end
+					if x > 1 and pixels[z][x-1][1] < 2 then
+						pixels[z][x-1] = { 1 }
+						pixels[z][x] = { 2 }
+					end
+					if x < size and pixels[z][x+1][1] < 2 then
+						pixels[z][x+1] = { 1 }
+						pixels[z][x] = { 2 }
+					end
+				end
 			end
 		end
-		color_map( 1, "group:water")
-		color_map( 2, "group:lava")
-		color_map( 3, "group:cracky")
-		color_map( 4, "group:crumbly")
-		color_map( 5, "group:stone")
-		color_map( 6, "group:soil")
-		color_map( 7, "group:spreading_dirt_type")
-		color_map( 8, "group:sand")
-		color_map( 9, "group:snowy")
-		color_map(10, "group:leaves")
-		color_map(11, "group:fire")
 
 		local filepath = textures_dir .. filename
 		tga_encoder.image(pixels):save(
@@ -160,7 +171,7 @@ minetest.register_on_joinplayer(
 			scale = { x = 4, y = 4 }
 		}
 		local dot_def = table.copy(map_def)
-		dot_def.text = "player.png^[resize:4x8"
+		dot_def.text = "maps_x.tga" -- "player.png^[resize:4x8"
 		maps.maps[player_name] = player:hud_add(map_def)
 		maps.dots[player_name] = player:hud_add(dot_def)
 		maps.minp[player_name] = { x=-32000, y=0, z=0 }