CoronaSDK-moveTo-mulit-screen support

main.lua

--[[
    moveTo function
    erinylin.com
    for Graphics 2.0 
]]--

display.setDefault("background", 1, 1, 1)

function moveTo(object, params)
    local T = display.screenOriginY -- Top
    local L = display.screenOriginX -- Left
    local R = display.viewableContentWidth - L -- Right
    local B = display.viewableContentHeight - T-- Bottom
    local cX, cY = display.contentCenterX, display.contentCenterY

    object.x, object.y = 0, 0
    local bounds = object.contentBounds
    local offsetX = (bounds.xMax + bounds.xMin) * 0.5
    local offsetY = (bounds.yMax + bounds.yMin) * 0.5
    local hW, hH = 0.5 * object.contentWidth , 0.5 * object.contentHeight
    if params.left then
        object.x = params.left+L + hW - offsetX
    elseif params.right then
        object.x = R-params.right - hW - offsetX
    elseif params.centerX then
        object.x = params.centerX + cX - offsetX
    end
    if params.bottom then
        object.y = B-params.bottom - hH - offsetY
    elseif params.top then
        object.y = params.top + T + hH - offsetY
    elseif params.centerY then
        object.y = params.centerY + cY - offsetY
    end
    return object
end

-------------------------------------
-- usage 
-------------------------------------
local rect1 = display.newRect( 0, 0, 50, 50 )
rect1:setFillColor(1, 0, 0)
moveTo(rect1, {top=0, left=0})

local rect2 = display.newRect( 0, 0, 50, 50 )
rect2:setFillColor(1, 0.2, 0)
moveTo(rect2, {top=0, right=0})

local rect3 = display.newRect( 0, 0, 50, 50 )
rect3:setFillColor(1, 0.4, 0)
moveTo(rect3, {bottom=0, right=0})

local rect4 = display.newRect( 0, 0, 50, 50 )
rect4:setFillColor(1, 0.6, 0)
moveTo(rect4, {bottom=0, left=0})

local group = display.newGroup()

local rect5 = display.newRect( 0, 0, 50, 50 )
rect5:setFillColor(1, 1, 0)
group:insert(rect5)

local rect6 = display.newRect( 0, 50, 50, 50 )
rect6:setFillColor(1, 0, 1)
group:insert(rect6)
-- ignore anchor settings
group.anchorX, group.anchorY= 0, 0
-- grouping moveTo
moveTo(group, {centerX=0, centerY=0})

local rect7 = display.newRect( 0, 0, 50, 50 )
rect7:setFillColor(0, 1, 1)
rect7.anchorX, rect7.anchorY= 0, 0
moveTo(rect7, {top=0, left=50})

"useage" -> "usage"