Ftf libs

Here are some longer code (classes) from the Gideros forum and some other places :-)

All samples are ready to use. Enjoy!

AUDIO

Producing Sound Without Resources @PaulH

Creates files on the fly using the .wav format for playback

-- https://forum.gideros.rocks/discussion/comment/68095/#Comment_68095
function make_wave(file_name, length, wave, freq, vol)
	-- We'll need to write some 32 bit values in binary. Helper function for that:
	local function to4Bytes(n) return n & 0xff, (n>>8) & 0xff, (n>>16) & 0xff, (n>>24) & 0xff end

	-- For a given point (sample number) in a wav file, return the 16 bit value for the specified sound wave and frequency
	local function sound_wave(wave,p,freq,vol)
		local sample_rate = 6000
		local n = 0 -- Default to silence
		if wave == "noise" then n = math.random(-255*128*vol, 255*128*vol)
		elseif wave == "sine" then n = math.floor(math.sin(p/sample_rate*freq*math.rad(180))*256*vol*127)
		elseif wave == "sawtooth" then n = math.floor((freq*p/sample_rate)*256*vol*256)
		end
		local c2, c1 = (n>>8) & 0xff, n & 0xff
		return string.char(c1, c2)
	end

	-- We're just dealing with a fixed format wav file:
	local sample_rate = 6000
	local samples = length*sample_rate
	local data_size = samples*2
	local total_file_length = 44+data_size
	local fl1, fl2, fl3, fl4 = to4Bytes(total_file_length)
	local ds1, ds2, ds3, ds4 = to4Bytes(data_size)
	local f = io.open(file_name, "wb")
	-- Write the WAV file header:
	f:write(
		string.char(
			82,73,70,70,--RIFF
			fl1, fl2, fl3, fl4,-- File size overall
			87,65,86,69,-- WAVE header
			102,109,116,32,--fmt chunk marker w/ trailing null
			16,0,0,0, -- Length of format data (16 bytes before this)
			1,0, -- Wave type. 1 == PCM
			1,0, -- Channels. 1 == mono
			112,23,0,0,-- Sample rate (Hertz)
			224,46,0,0, -- Bits per sample * channels * sample rate / 8
			2,0,
			16,0, -- Bytes per sample - this is 16 
			100,97,116,97, -- "data" - chunk header
			ds1,ds2,ds3,ds4-- size of data section
		)
	)
	-- Write the data:
	for l = 1, samples do
		f:write(sound_wave(wave,l,freq, vol or 1))
	end
	f:close()
end

-- Demo some white noise:
--make_wave("|D|noise.wav", 1, "noise") -- 0.1 second sine wave at 256 Herz (middle C) at full volume
--s=Sound.new("|D|noise.wav")
--s:play()

-- one note with a sawtooth wave:
--make_wave("|D|note.wav", 2, "sawtooth", 262, 1) -- 0.1 second sine wave at 256 Herz (middle C) at full volume
--s=Sound.new("|D|note.wav")
--s:play()

-- Make wave files for the chromatic scale.
-- The frequencies in Hertz of the notes in octave zero:
notes = { 16.35, 17.32, 18.35, 19.45, 20.60, 21.83, 23.12, 24.5, 25.96, 27.50, 29.14, 30.87 }
-- 3 letter names for those notes:
names = { "C0n", "C0s", "D0n", "D0s", "E0n", "F0n", "F0s", "G0n", "G0s", "A0n", "A0s", "B0n" }
-- Compute the ratio of each note to the C:
local note_multipliers = {}
for i = 1, #notes do
	note_multipliers[i] = notes[i]/notes[1]
end

-- Make a sound for each note in several octaves:
local sounds = {}
for octave = 3, 7 do
	for i = 1, #names do
		local original_note = names[i]
		local octave_note = string.gsub(original_note, "0", octave)
		local file_name = "|D|note_" .. octave_note .. ".wav"
		-- Compute the frequency for the note by applying the ratio of that note over C
		-- and then apply the octave multiplier. Each octave is double the frequency
		-- of the one below it:
		local fr = math.floor(notes[1] * note_multipliers[i] * math.pow(2, octave))
		-- We'll make each note 0.2 seconds, using a sine wave
		--function make_wave(file_name, length, wave, freq, vol)
		make_wave(file_name, 0.2, "sine", fr, 1)
		sounds[octave_note] = Sound.new(file_name)
	end
end

-- Given a string of 3 letter note names, play those notes in order:
function play_sequence(seq)
	for i = 1, string.len(seq), 3 do
		local note = string.sub(seq, i, i+2)
		if sounds[note] then
			Timer.delayedCall(60 * (i-1), function()
				sounds[note]:play()
			end)
		end
	end
end

local fur_elise =
	"E4nD4sE4nD4sE4nB3nD4nC4nA3n      "..
	"C3nE3nA3nB3n      "..
	"E3nG3sB3nC4n      "..
	"E3nE4nD4sE4nD4sE4nB3nD4nC4nA3n      "..
	"C3nE3nA3nB3n      "..
	"E3nC4nB3nA3n"
play_sequence(fur_elise)
-- To play an octave higher:
Timer.delayedCall(9000, function()
	play_sequence(string.gsub(string.gsub(fur_elise,"4","5"),"3","4"))
end)

STRING

Score Counting TextField @errorpi

--[[
	Score Counting TextField
	by: @errorpi
]]

Score = Core.class(Sprite)
 
function Score:init(xscore, xincrease)
	self.score = xscore or 0
	self.countTime = (xincrease or 5) * 100
	-- a textfield
	self.scoreText = TextField.new(nil, tostring(self.score))
	self.scoreText:setLayout({wid = 80, hei = 40, flags=FontBase.TLF_CENTER})
	self.scoreText:setTextColor(math.random(0xffffff))
	self.scoreText:setScale(5)
	self.scoreText:setPosition(64, 64)
	self:addChild(self.scoreText)
	-- a timer
	self.t = Timer.new(1) -- timer init
	self.t:addEventListener(Event.TIMER, self.updateText, self)
end
 
function Score:updateText()
	local displayScore = tonumber(self.scoreText:getText())
	if displayScore < self.score then
		self.scoreText:setText(tostring( displayScore + 1) )
	end
end

function Score:addScore(add)
	self.score += add
	local displayScore = tonumber(self.scoreText:getText())
	-- set timer properties (bigger add score means faster steps)
	local tRepeat = self.score - displayScore
	local tDelay =  self.countTime / tRepeat
	self.t:stop()
	self.t:reset()
	self.t:setDelay(tDelay)
	self.t:setRepeatCount(tRepeat)
	self.t:start()

	return self.score
end

--------------------
application:setBackgroundColor(0x4d4d4d)
-- demo
local initialscore = 500
local score = Score.new(initialscore, 6) -- initial score value, increase speed
stage:addChild(score)
local earnedpoints = 300

Timer.delayedCall(3000, function()
	score:addScore(earnedpoints) -- target score value
end)

GFX

Hex to Number / Number to Hex @hanzhao

--[[
Lua Hex v0.4
-------------------
Hex conversion lib for Lua.

How to use:
 lhex.to_hex(n) -- convert a number to a hex string
 lhex.to_dec(hex) -- convert a hex "string" (prefix with "0x..." or "0X...") to number

Part of LuaBit(http://luaforge.net/projects/bit/).

Under the MIT license.

copyright(c) 2006~2007 hanzhao (abrash_han@hotmail.com)
--]]

local function to_bits(n)
	-- checking not float
	if(n - (n//1) > 0) then error("trying to apply bitwise operation on non-integer!") end
	if(n < 0) then return to_bits(~(n//1) + 1) end -- negative
	-- to bits table
	local tbl = {}
	local cnt = 1
	while (n > 0) do
		local last = n%2
		if(last == 1) then tbl[cnt] = 1
		else tbl[cnt] = 0
		end
		n = (n-last)/2
		cnt += 1
	end
	return tbl
end

local function tbl_to_number(tbl)
	local n = #tbl
	local rslt = 0
	local power = 1
	for i = 1, n do
		rslt += tbl[i]*power
		power *= 2
	end
	return rslt
end

local function to_hex(n)
	if(type(n) ~= "number") then error("non-number type passed in.") end
	-- checking not float
	if(n - (n//1) > 0) then error("trying to apply bitwise operation on non-integer!") end
	if(n < 0) then -- negative
		n = to_bits(~(-n<>n) + 1)
		n = tbl_to_number(n)
	end
	local hex_tbl = { "A", "B", "C", "D", "E", "F" }
	local hex_str = ""
	while(n ~= 0) do
		local last = n%16
		if(last < 10) then hex_str = tostring(last) .. hex_str
		else hex_str = hex_tbl[last-10+1] .. hex_str
		end
		n = (n/16)//1 -- floor
	end
	if(hex_str == "") then hex_str = "0" end
	return "0x"..hex_str
end

local function to_dec(hexstring)
	if(type(hexstring) ~= "string") then error("non-string type passed in.") end
	local head = string.sub(hexstring, 1, 2)
	if(head ~= "0x" and head ~= "0X") then error("wrong hex format, should lead by 0x or 0X.") end
	return tonumber(hexstring:sub(3), 16) -- base 16
end

--------------------
-- lua hex lib interface
lhex = {
	to_hex=to_hex,
	to_dec=to_dec,
}

--------------------
-- examples
local dec = 4341688
local hex = lhex.to_hex(dec) -- number to hex
print(hex) -- 0x423FB8
local revdec = lhex.to_dec(hex) -- hex string (prefix with "0x" or "0X") to number
print(revdec) -- 4341688

print(lhex.to_dec("0x0")) -- 0, hex string (prefix with "0x" or "0X") to number
print(lhex.to_dec("0x00ff00")) -- 65280, hex string (prefix with "0x" or "0X") to number
print(lhex.to_hex(16777215)) -- 0xFFFFFF, number to hex

local pix = Pixel.new(lhex.to_hex(56816), 1, 32, 32)
stage:addChild(pix)

print("hex is", hex)

FILES

Get Files in Folder @xxx

note: requires the Lfs plugin

Gets all the files in a folder matching a file extension and store them in a list.

local myos = application:getDeviceInfo()
local iswin32 = if myos == "win32" then true else false
--print(iswin32)

function getFilesInFolder(xpath, xlist)
	local lfs = require "lfs"
	for file in lfs.dir(xpath) do
		if file ~= "." and file ~= ".." then
			if file:match(".png$") then -- choose your file extension here
				if iswin32 then
					local f = xpath.."\\"..file
--					print(f)
					xlist[#xlist + 1] = f:gsub("/", "\\")
				else
					local f = xpath.."/"..file
--					print(f)
					xlist[#xlist + 1] = f:gsub("\\", "/")
				end
			end
		end
	end
	lfs = nil
end

Demo code using ButtonMonster

local myos = application:getDeviceInfo()
local iswin32 = if myos == "win32" then true else false
--print(iswin32)

local folderimages = {} -- list all images in user selected folder
local images = {} -- list all images with valid extension
local btnimagefolder = ButtonMonster.new({
	pixelcolorup=0xffaa00, text="import images", textcolorup=0xaa0000, textscalex=3,
	isautoscale=true,
})
btnimagefolder:setPosition(16, 16)
stage:addChild(btnimagefolder)
btnimagefolder:addEventListener("clicked", function()
	local path
	if iswin32 then path = application:get("openDirectoryDialog", "Select Folder", "C:\\tmp\\")
	else path = application:get("openDirectoryDialog", "Select Folder", "C:/tmp/")
	end -- print(path)
	if path then getFilesInFolder(path, folderimages) end
	if folderimages and #folderimages > 0 then
		for i = 1, #folderimages do
			images[i] = Bitmap.new(Texture.new(folderimages[i]), true)
			images[i]:setAnchorPoint(0.5, 1)
			images[i]:setPosition(8, 8)
			-- ...
		end
	end
end)

Xml Parser @Alexander Makeev

-----------------------------------------------------------------------------------------
-- LUA only XmlParser from Alexander Makeev
-----------------------------------------------------------------------------------------
XmlParser = {}

function XmlParser:ToXmlString(value)
	value = string.gsub(value, "&", "&")		-- '&' -> "&"
	value = string.gsub(value, "<", "&lt;")		-- '<' -> "&lt;"
	value = string.gsub(value, ">", "&gt;")		-- '>' -> "&gt;"
	--value = string.gsub(value, "'", "&apos;")	-- '\'' -> "&apos;"
	value = string.gsub(value, "\"", "&quot;")	-- '"' -> "&quot;"
	-- replace non printable char -> "&#xD;"
	value = string.gsub(value, "([^%w%&%;%p%\t% ])", function(c)
		return string.format("&#x%X;", string.byte(c))
		--return string.format("&#x%02X;", string.byte(c))
		--return string.format("&#%02d;", string.byte(c))
	end)
	return value
end

function XmlParser:FromXmlString(value)
	value = string.gsub(value, "&#x([%x]+)%;", function(h)
		return string.char(tonumber(h,16))
	end)
	value = string.gsub(value, "&#([0-9]+)%;", function(h)
		return string.char(tonumber(h,10))
	end)
	value = string.gsub(value, "&quot;", "\"")
	value = string.gsub(value, "&apos;", "'")
	value = string.gsub(value, "&gt;", ">")
	value = string.gsub(value, "&lt;", "<")
	value = string.gsub(value, "&amp;", "&")
	return value
end
   
function XmlParser:ParseArgs(s)
	local arg = {}
	string.gsub(s, "(%w+)=([\"'])(.-)%2", function(w, _, a)
		arg[w] = self:FromXmlString(a)
	end)
	return arg
end

function XmlParser:ParseXmlText(xmlText)
	local stack = {}
	local top = { Name=nil, Value=nil, Attributes={}, ChildNodes={} }
	table.insert(stack, top)
	local ni, c, label, xarg, empty
	local i, j = 1, 1
	while true do
		ni, j, c, label, xarg, empty = string.find(xmlText, "<(%/?)([%w:]+)(.-)(%/?)>", i)
		if not ni then break end
		local text = string.sub(xmlText, i, ni-1)
		if not string.find(text, "^%s*$") then
			top.Value=(top.Value or "")..self:FromXmlString(text)
		end
		if empty == "/" then -- empty element tag
			table.insert(top.ChildNodes,
				{
					Name=label, Value=nil, Attributes=self:ParseArgs(xarg), ChildNodes={}
				}
			)
		elseif c == "" then -- start tag
			top = { Name=label, Value=nil, Attributes=self:ParseArgs(xarg), ChildNodes={} }
			table.insert(stack, top) -- new level
			--log("openTag ="..top.Name)
		else -- end tag
			local toclose = table.remove(stack) -- remove top
			--log("closeTag="..toclose.Name)
			top = stack[#stack]
			if #stack < 1 then
				error("XmlParser: nothing to close with "..label)
			end
			if toclose.Name ~= label then
				error("XmlParser: trying to close "..toclose.Name.." with "..label)
			end
			table.insert(top.ChildNodes, toclose)
		end
		i = j + 1
	end
	local text = string.sub(xmlText, i)
	if not string.find(text, "^%s*$") then
		stack[#stack].Value=(stack[#stack].Value or "")..self:FromXmlString(text)
	end
	if #stack > 1 then
		error("XmlParser: unclosed "..stack[stack.n].Name)
	end
	return stack[1].ChildNodes[1]
end

function XmlParser:ParseXmlFile(xmlFileName)
	local hFile, err = io.open(xmlFileName,"r")
	if (not err) then
		local xmlText=hFile:read("*a") -- read file content
		io.close(hFile)
		return self:ParseXmlText(xmlText),nil
	else
		return nil, err
	end
end

--[[
-- Usage:
-- parse xml
local xml = XmlParser:ParseXmlText(myxmlfile)
]]

TABLE

Var Dump @xxx

function vardump(value, depth, key)
	local linePrefix = ""
	local spaces = ""

	if key ~= nil then
		linePrefix = "["..key.."] = "
	end

	if depth == nil then
		depth = 0
	else
		depth = depth + 1
		for i = 1, depth do
			spaces = spaces .. "  "
		end
	end

	if type(value) == 'table' then
		local mTable = getmetatable(value)
		if mTable == nil then
			print(spaces ..linePrefix.."(table) ")
		else
			print(spaces .."(metatable) ")
			value = mTable
		end		
		for tableKey, tableValue in pairs(value) do
			vardump(tableValue, depth, tableKey)
		end
	elseif type(value) == 'function' or
		type(value)	== 'thread' or
		type(value)	== 'userdata' or
		value == nil
		then
		print(spaces..tostring(value))
	else
		print(spaces..linePrefix.."("..type(value)..") "..tostring(value))
	end
end

--[[
Usage:
foo="Hello world"
vardump(foo)
vardump( { print, 12, nil, io.stdin, math } )

foo = {
	"zero",1,2,3,{1,{1,2,3,4,{1,2,{1,"cool",2},4},6},3,vardump,5,6},          5,{Mary=10, Paul="10"},"last value"
}
vardump(foo)
--]]

More to come God's willing...

---

• Main Page
• Lua API
• Main API
• Plugins