Use PNG instead of TGA

mods/CORE/tga_encoder/README.md

@@ -1,4 +0,0 @@
-# tga_encoder
-A TGA Encoder written in Lua without the use of external Libraries.
-
-May be used as a Minetest mod.

mods/CORE/tga_encoder/init.lua

@@ -1,109 +0,0 @@
-tga_encoder = {}
-
-local LUA_ARGS_LIMIT = 1000
-
-local image = setmetatable({}, {
-	__call = function(self, ...)
-		local t = setmetatable({}, {__index = self})
-		t:constructor(...)
-		return t
-	end,
-})
-
-function image:constructor(pixels)
-	self.bytes = {}
-	self.chunks = {self.bytes}
-	self.pixels = pixels
-	self.width = #pixels[1]
-	self.height = #pixels
-
-	self:encode()
-end
-
-function image:insert(byte)
-	table.insert(self.bytes, byte)
-	if #self.bytes == LUA_ARGS_LIMIT then
-		self.bytes = {}
-		table.insert(self.chunks, self.bytes)
-	end
-end
-
-function image:littleendian(size, value)
-	for i = 1, size do
-		local byte = value % 256
-		value = value - byte
-		value = value / 256
-		self:insert(byte)
-	end
-end
-
-function image:encode_colormap_spec()
-	-- first entry index
-	self:littleendian(2, 0)
-	-- number of entries
-	self:littleendian(2, 0)
-	-- number of bits per pixel
-	self:insert(0)
-end
-
-function image:encode_image_spec()
-	-- X- and Y- origin
-	self:littleendian(2, 0)
-	self:littleendian(2, 0)
-	-- width and height
-	self:littleendian(2, self.width)
-	self:littleendian(2, self.height)
-	-- pixel depth
-	self:insert(24)
-	-- image descriptor
-	self:insert(0)
-end
-
-function image:encode_header()
-	-- id length
-	self:insert(0) -- no image id info
-	-- color map type
-	self:insert(0) -- no color map
-	-- image type
-	self:insert(2) -- uncompressed true-color image
-	-- color map specification
-	self:encode_colormap_spec()
-	-- image specification
-	self:encode_image_spec()
-end
-
-function image:encode_data()
-	for _, row in ipairs(self.pixels) do
-		for _, pixel in ipairs(row) do
-			self:insert(pixel[3])
-			self:insert(pixel[2])
-			self:insert(pixel[1])
-		end
-	end
-end
-
-function image:encode()
-	-- encode header
-	self:encode_header()
-	-- no color map and image id data
-	-- encode data
-	self:encode_data()
-	-- no extension area
-end
-
-function image:get_data()
-	local data = ""
-	for _, bytes in ipairs(self.chunks) do
-		data = data .. string.char(unpack(bytes))
-	end
-	return data .. string.char(0, 0, 0, 0) .. string.char(0, 0, 0, 0) .. "TRUEVISION-XFILE." .. string.char(0)
-end
-
-function image:save(filename)
-	self.data = self.data or self:get_data()
-	local f = assert(io.open(filename, "w"))
-	f:write(self.data)
-	f:close()
-end
-
-tga_encoder.image = image

mods/CORE/tga_encoder/mod.conf

@@ -1,3 +0,0 @@
-name = tga_encoder
-author = Fleckenstein
-description = A TGA Encoder written in Lua without the use of external Libraries.

mods/ITEMS/mcl_maps/bit32.lua

@@ -0,0 +1,98 @@
+bit32 = {}
+
+local N = 32
+local P = 2^N
+
+function bit32.bnot(x)
+	x = x % P
+	return P - 1 - x
+end
+
+function bit32.band(x, y)
+	-- Common usecases, they deserve to be optimized
+	if y == 0xff then return x % 0x100 end
+	if y == 0xffff then return x % 0x10000 end
+	if y == 0xffffffff then return x % 0x100000000 end
+	
+	x, y = x % P, y % P
+	local r = 0
+	local p = 1
+	for i = 1, N do
+		local a, b = x % 2, y % 2
+		x, y = math.floor(x / 2), math.floor(y / 2)
+		if a + b == 2 then
+			r = r + p
+		end
+		p = 2 * p
+	end
+	return r
+end
+
+function bit32.bor(x, y)
+	-- Common usecases, they deserve to be optimized
+	if y == 0xff then return x - (x%0x100) + 0xff end
+	if y == 0xffff then return x - (x%0x10000) + 0xffff end
+	if y == 0xffffffff then return 0xffffffff end
+	
+	x, y = x % P, y % P
+	local r = 0
+	local p = 1
+	for i = 1, N do
+		local a, b = x % 2, y % 2
+		x, y = math.floor(x / 2), math.floor(y / 2)
+		if a + b >= 1 then
+			r = r + p
+		end
+		p = 2 * p
+	end
+	return r
+end
+
+function bit32.bxor(x, y)
+	x, y = x % P, y % P
+	local r = 0
+	local p = 1
+	for i = 1, N do
+		local a, b = x%2, y%2
+		x, y = math.floor(x/2), math.floor(y/2)
+		if a + b == 1 then
+			r = r + p
+		end
+		p = 2 * p
+	end
+	return r
+end
+
+function bit32.lshift(x, s_amount)
+	if math.abs(s_amount) >= N then return 0 end
+	x = x % P
+	if s_amount < 0 then
+		return math.floor(x * (2 ^ s_amount))
+	else
+		return (x * (2 ^ s_amount)) % P
+	end
+end
+
+function bit32.rshift(x, s_amount)
+	if math.abs(s_amount) >= N then return 0 end
+	x = x % P
+	if s_amount > 0 then
+		return math.floor(x * (2 ^ - s_amount))
+	else
+		return (x * (2 ^ -s_amount)) % P
+	end
+end
+
+function bit32.arshift(x, s_amount)
+	if math.abs(s_amount) >= N then return 0 end
+	x = x % P
+	if s_amount > 0 then
+		local add = 0
+		if x >= P/2 then
+			add = P - 2 ^ (N - s_amount)
+		end
+		return math.floor(x * (2 ^ -s_amount)) + add
+	else
+		return (x * (2 ^ -s_amount)) % P
+	end
+end

mods/ITEMS/mcl_maps/init.lua

@@ -7,6 +7,11 @@ local worldpath = minetest.get_worldpath()
 local map_textures_path = worldpath .. "/mcl_maps/"
 local last_finished_id = storage:get_int("next_id") - 1
 
+dofile(modpath .. "/bit32.lua") -- taken from http://gitea.minetest.one/minetest-mods/turtle/src/branch/master/bit32.lua
+
+bit = bit32
+pngencoder = dofile(modpath .. "/pngencoder.lua") -- taken from https://github.com/wyozi/lua-pngencoder/blob/master/pngencoder.lua
+
 minetest.mkdir(map_textures_path)
 
 local function load_json_file(name)
@@ -32,7 +37,7 @@ function mcl_maps.create_map(pos)
 	local meta = itemstack:get_meta()
 	local id = storage:get_int("next_id")
 	storage:set_int("next_id", id + 1)
-	local texture_file = "mcl_maps_map_texture_" .. id .. ".tga"
+	local texture_file = "mcl_maps_map_texture_" .. id .. ".png"
 	local texture_path = map_textures_path .. texture_file
 	local texture = "[combine:140x140:0,0=mcl_maps_map_background.png:6,6=" .. texture_file
 	meta:set_int("mcl_maps:id", id)
@@ -121,7 +126,16 @@ function mcl_maps.create_map(pos)
 			end
 			last_heightmap = heightmap
 		end
-		tga_encoder.image(pixels):save(texture_path)
+		local image = pngencoder(128, 128, "rgb")
+		for _, row in ipairs(pixels) do
+			for _, pixel in ipairs(row) do
+				image:write(pixel)
+			end
+		end
+		assert(image.done)
+		local f = assert(io.open(texture_path, "w"))
+		f:write(table.concat(image.output))
+		f:close()
 		creating_maps[texture] = false
 	end)
 	return itemstack

mods/ITEMS/mcl_maps/mod.conf

@@ -1,2 +1,2 @@
 name = mcl_maps
-depends = mcl_core, mcl_flowers, tga_encoder, tt, mcl_colors
+depends = mcl_core, mcl_flowers, tt, mcl_colors

mods/ITEMS/mcl_maps/pngencoder.lua

@@ -0,0 +1,190 @@
+local Png = {}
+Png.__index = Png
+
+local DEFLATE_MAX_BLOCK_SIZE = 65535
+
+local function putBigUint32(val, tbl, index)
+    for i=0,3 do
+        tbl[index + i] = bit.band(bit.rshift(val, (3 - i) * 8), 0xFF)
+    end
+end
+
+function Png:writeBytes(data, index, len)
+    index = index or 1
+    len = len or #data
+    for i=index,index+len-1 do
+        table.insert(self.output, string.char(data[i]))
+    end
+end
+
+function Png:write(pixels)
+    local count = #pixels  -- Byte count
+    local pixelPointer = 1
+    while count > 0 do
+        if self.positionY >= self.height then
+            error("All image pixels already written")
+        end
+
+        if self.deflateFilled == 0 then -- Start DEFLATE block
+            local size = DEFLATE_MAX_BLOCK_SIZE;
+            if (self.uncompRemain < size) then
+                size = self.uncompRemain
+            end
+            local header = {  -- 5 bytes long
+                bit.band((self.uncompRemain <= DEFLATE_MAX_BLOCK_SIZE and 1 or 0), 0xFF),
+                bit.band(bit.rshift(size, 0), 0xFF),
+                bit.band(bit.rshift(size, 8), 0xFF),
+                bit.band(bit.bxor(bit.rshift(size, 0), 0xFF), 0xFF),
+                bit.band(bit.bxor(bit.rshift(size, 8), 0xFF), 0xFF),
+            }
+            self:writeBytes(header)
+            self:crc32(header, 1, #header)
+        end
+        assert(self.positionX < self.lineSize and self.deflateFilled < DEFLATE_MAX_BLOCK_SIZE);
+
+        if (self.positionX == 0) then  -- Beginning of line - write filter method byte
+            local b = {0}
+            self:writeBytes(b)
+            self:crc32(b, 1, 1)
+            self:adler32(b, 1, 1)
+            self.positionX = self.positionX + 1
+            self.uncompRemain = self.uncompRemain - 1
+            self.deflateFilled = self.deflateFilled + 1
+        else -- Write some pixel bytes for current line
+            local n = DEFLATE_MAX_BLOCK_SIZE - self.deflateFilled;
+            if (self.lineSize - self.positionX < n) then
+                n = self.lineSize - self.positionX
+            end
+            if (count < n) then
+                n = count;
+            end
+            assert(n > 0);
+
+            self:writeBytes(pixels, pixelPointer, n)
+
+            -- Update checksums
+            self:crc32(pixels, pixelPointer, n);
+            self:adler32(pixels, pixelPointer, n);
+
+            -- Increment positions
+            count = count - n;
+            pixelPointer = pixelPointer + n;
+            self.positionX = self.positionX + n;
+            self.uncompRemain = self.uncompRemain - n;
+            self.deflateFilled = self.deflateFilled + n;
+        end
+
+        if (self.deflateFilled >= DEFLATE_MAX_BLOCK_SIZE) then
+            self.deflateFilled = 0; -- End current block
+        end
+
+        if (self.positionX == self.lineSize) then  -- Increment line
+            self.positionX = 0;
+            self.positionY = self.positionY + 1;
+            if (self.positionY == self.height) then -- Reached end of pixels
+                local footer = {  -- 20 bytes long
+                    0, 0, 0, 0,  -- DEFLATE Adler-32 placeholder
+                    0, 0, 0, 0,  -- IDAT CRC-32 placeholder
+                    -- IEND chunk
+                    0x00, 0x00, 0x00, 0x00,
+                    0x49, 0x45, 0x4E, 0x44,
+                    0xAE, 0x42, 0x60, 0x82,
+                }
+                putBigUint32(self.adler, footer, 1)
+                self:crc32(footer, 1, 4)
+                putBigUint32(self.crc, footer, 5)
+                self:writeBytes(footer)
+                self.done = true
+            end
+        end
+    end
+end
+
+function Png:crc32(data, index, len)
+    self.crc = bit.bnot(self.crc)
+    for i=index,index+len-1 do
+        local byte = data[i]
+        for j=0,7 do  -- Inefficient bitwise implementation, instead of table-based
+            local nbit = bit.band(bit.bxor(self.crc, bit.rshift(byte, j)), 1);
+            self.crc = bit.bxor(bit.rshift(self.crc, 1), bit.band((-nbit), 0xEDB88320));
+        end
+    end
+    self.crc = bit.bnot(self.crc)
+end
+function Png:adler32(data, index, len)
+    local s1 = bit.band(self.adler, 0xFFFF)
+    local s2 = bit.rshift(self.adler, 16)
+    for i=index,index+len-1 do
+        s1 = (s1 + data[i]) % 65521
+        s2 = (s2 + s1) % 65521
+    end
+    self.adler = bit.bor(bit.lshift(s2, 16), s1)
+end
+
+local function begin(width, height, colorMode)
+    -- Default to rgb
+    colorMode = colorMode or "rgb"
+
+    -- Determine bytes per pixel and the PNG internal color type
+    local bytesPerPixel, colorType
+    if colorMode == "rgb" then
+        bytesPerPixel, colorType = 3, 2
+    elseif colorMode == "rgba" then
+        bytesPerPixel, colorType = 4, 6
+    else
+        error("Invalid colorMode")
+    end
+
+    local state = setmetatable({ width = width, height = height, done = false, output = {} }, Png)
+
+    -- Compute and check data siezs
+    state.lineSize = width * bytesPerPixel + 1
+    -- TODO: check if lineSize too big
+
+    state.uncompRemain = state.lineSize * height
+
+    local numBlocks = math.ceil(state.uncompRemain / DEFLATE_MAX_BLOCK_SIZE)
+
+    -- 5 bytes per DEFLATE uncompressed block header, 2 bytes for zlib header, 4 bytes for zlib Adler-32 footer
+    local idatSize = numBlocks * 5 + 6
+    idatSize = idatSize + state.uncompRemain;
+
+    -- TODO check if idatSize too big
+
+    local header = {  -- 43 bytes long
+        -- PNG header
+        0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A,
+        -- IHDR chunk
+        0x00, 0x00, 0x00, 0x0D,
+        0x49, 0x48, 0x44, 0x52,
+        0, 0, 0, 0,  -- 'width' placeholder
+        0, 0, 0, 0,  -- 'height' placeholder
+        0x08, colorType, 0x00, 0x00, 0x00,
+        0, 0, 0, 0,  -- IHDR CRC-32 placeholder
+        -- IDAT chunk
+        0, 0, 0, 0,  -- 'idatSize' placeholder
+        0x49, 0x44, 0x41, 0x54,
+        -- DEFLATE data
+        0x08, 0x1D,
+    }
+    putBigUint32(width, header, 17)
+    putBigUint32(height, header, 21)
+    putBigUint32(idatSize, header, 34)
+
+    state.crc = 0
+    state:crc32(header, 13, 17)
+    putBigUint32(state.crc, header, 30)
+    state:writeBytes(header)
+
+    state.crc = 0
+    state:crc32(header, 38, 6);  -- 0xD7245B6B
+    state.adler = 1
+
+    state.positionX = 0
+    state.positionY = 0
+    state.deflateFilled = 0
+
+    return state
+end
+
+return begin