walterlua

-- table.indexOf( array, object ) returns the index
-- of object in array. Returns 'nil' if not in array.
table.indexOf = function( t, object )
	local result

	if "table" == type( t ) then
		for i=1,#t do
			if object == t[i] then
				result = i
				break

walterlua

-- math.round( num ) rounds num to the nearest integer following the 
-- same rules as the JavaScript version, i.e. if the fractional 
-- portion of number is .5 or greater, the argument is rounded to the 
-- next higher integer. If the fractional portion of number is less 
-- than .5, the argument is rounded to the next lower integer.
math.round = function(num) 
	return math.floor(num+.5)
end

-- Example Usage:

walterlua

-- table.copy( array, ... ) returns a shallow copy of array. 
-- A variable number of additional arrays can be passed in as 
-- optional arguments. If an array has a hole (a nil entry), 
-- copying in a given source array stops at the last consecutive
-- item prior to the hole.
-- 
-- Note: In Lua, the function table.concat() is equivalent 
-- to JavaScript's array.join(). Hence, the following function
-- is called copy().
table.copy = function( t, ... )

walterlua

math.round = function(num) 
	return math.floor(num+.5)
end

local function testRound( num )
	print( num, math.round( num ) )
end

testRound( 0.1 )
testRound( 0.5 )

walterlua

0.1	0
0.5	1
8.9	9
-0.1	0
-0.5	0
-8.9	-9

walterlua

function print2( var, name )
  if not name then name = "anonymous" end
  if "table" ~= type( var ) then
    print( name .. " = " .. tostring( var ) )
  else
    -- for tables, recurse through children
    for k,v in pairs( var ) do
      local child
      if 1 == string.find( k, "%a[%w_]*" ) then
        -- key can be accessed using dot syntax

walterlua

-- Example:
local t = { foo="bar", a=3, b=false, [" blah"] = "lah", ["12s{@#}$#)@*"]=3}
print2( t, "t" )

-- Output:
t.a = 3
t[" blah"] = lah
t.b = false
t["12s{@#}$#)@*"] = 3
t.foo = bar

walterlua

local w,h = display.contentWidth*0.5, display.contentHeight*0.5
local halfW,halfH = 0.5*w, 0.5*h
local background = display.newImageRect( "world.jpg", w,h )
background:translate( halfW, halfH )

local dw = w + halfW
local dh = h + halfH

local background = display.newImageRect( "world.jpg", w,h )
background:setFillColor( 255, 255, 0 )

walterlua

local myText = display.newText( "Hello, World!", 0, 0, native.systemFont, 40 )
myText.x = display.contentWidth * 0.5
myText.y = display.contentWidth * 0.25
local g = graphics.newGradient( { 255, 255, 0 }, { 200 }, "down" )
myText:setTextColor( g )

walterlua

local isTall = ( "iPhone" == system.getInfo( "model" ) ) and ( display.pixelHeight > 960 )