http://pastebin.com/embed_js.php?i=9BJvrPJt

Don't be put off by the size of the code provided, there are some big examples that take up most of the space!

Comments and suggestions welcome, I am still learning.

Reason is I want to be able to detect size of a sprite based on the arbitrary jpg it's made from. Thought if I used the jpg to make an image instance, I could use image.width and image.height for the purpose. No?

As an example, running this compression on the images used in MineSweeper created files 28 times smaller. You can see the tutorial here: http://codeatuts.blogspot.com.au/2013/02/tutorial-26-rle-image-compression-for.html

Comments welcome as always.

.@Mark - maybe you could build this into the next version of Spritely?

If not, is there any chance this could be added in a future update?

displayMode(FULLSCREEN)

function setup()
    map = nil
    http.request('http://maps.googleapis.com/maps/api/staticmap?center=40.714728,-73.998672&zoom=12&size=400x400&sensor=false', didGetImage)
end

function didGetImage(theImage, status, head)
    map = theImage
end

function draw()
    background(226, 226, 226, 255)
    if map ~= nil then
        sprite(map, WIDTH/2, HEIGHT/2)
    end
end

Pretty spiffy. And if you look at the static maps API, you'll find there's a lot you can do with it.

Now, imagine if we had the compass heading and GPS values. We'd be well on our way to our own Codea-based mapping tool.

The background is made up of four image panes, because of the limitation in rendering to large images discussed here. To keep things simple, the background pattern is drawn four times, each time being clipped to one of the panes. With displayMode(STANDARD), hairline gaps appear between the panes that spoil the effect. They disappear with displayMode(FULLSCREEN).

The colouring makes use of the relationship between HSV and RGB to create a spectrum.

The pattern is based on the golden angle and Helmut Vogel's construction of the sunflower head(Fermat's spiral).

--
-- Golden Angle
-- 

displayMode(FULLSCREEN)
supportedOrientations(LANDSCAPE_ANY)
function setup()
    scale, dot, spin = 6, 10, 24
    local pi2 = 2 * math.pi
    local phi = (1 + math.sqrt(5)) / 2 -- Golden ratio
    local ga = pi2 / phi ^ 2           -- Golden angle (radians)
    w2, h2 = WIDTH / 2, HEIGHT / 2
    local radius = math.sqrt(w2 * w2 + h2 * h2)
    local max = (radius / scale) ^ 2   -- Number of dots
    len2 = (radius * 2 + dot) / 2      -- Size of each quarter tile
    img, ox, oy = {}, {}, {}
    for j = 0, 3 do
        img[j] = image(len2, len2)
        setContext(img[j])
        ox[j] = -(j % 2) * len2
        oy[j] = -(1 - math.floor(j / 2)) * len2
        local ang = 0
        for i = 1, max do 
            local l = math.sqrt(i) * scale
            local x, y = l * math.cos(ang), l * math.sin(ang)
            local r, g, b = H2RGB(l / radius)
            fill(r, g, b)
            ellipse(x - ox[j], y - oy[j], dot)
            ang = (ang + ga) % pi2
        end
        setContext()
    end
    spriteMode(CORNER)
end

function draw()
    background(0)
    translate(w2, h2)
    rotate(ElapsedTime * spin % 360)
    for i = 0, 3 do sprite(img[i], ox[i], oy[i]) end
end

-- Hue (nil or [0, 1)) to RGB; (S = 1, V = 1)
function H2RGB(h)
    if not h then return 0, 0, 0 end
    local r, g, b
    local h1 = h * 6
    local x = (1 - math.abs(h1 % 2 - 1))
    if h1 < 1 then r, g, b = 1, x, 0
    elseif h1 < 2 then r, g, b = x, 1, 0
    elseif h1 < 3 then r, g, b = 0, 1, x
    elseif h1 < 4 then r, g, b = 0, x, 1
    elseif h1 < 5 then r, g, b = x, 0, 1
    elseif h1 < 6 then r, g, b = 1, 0, x end
    return 255 * r, 255 * g, 255 * b
end

Main (part 1 of 3)

dothidden=false

function setup()
    saveProjectInfo("Description","Distort picture using a grid mesh")
    
    print("2 finger tap --- toggle full screen")
    print("1 finger tap --- toggle control points")
    print("Move Points to distort")
    
    touches=0
    gesture=0
    
    -- pFIXBORDERS=false 
    FIXBORDERS = false -- Border points are movable
    
    pnX=1 -- n columns
    iparameter("nX",2,16,4)
    pnY=1 -- n rows
    iparameter("nY",2,16,4)
    
    pstate=0 -- cumulate distortion
    iparameter("Savestate",0,1,0)
    
    iparameter("DoWave",0,1,0) -- apply saw effect
    iparameter("HWave",0,2,0) -- horz 0, vert 1, both 2
    
    iparameter("DoReset",0,1,0) -- reset to prior saved state
    
    ImgW=0
    ImgH=0
    theMesh=mesh()
    ActivePoint=nil
    ActiveId=-1   
    CpGrid={} -- control points
    CpRect={} -- grid cells
    
    -- LOAD YOUR OWN HERE
    -- local BaseImg = readImage("Planet Cute:Icon")
    local BaseImg =  CreateMyImage(600,600)
    
    theMesh.texture=BaseImg
    ImgW=BaseImg.width
    ImgH=BaseImg.height
    
    OrigW=ImgW
    OrigH=ImgH
    
    local Tw,Th,Zom=ResizeToFit(ImgW,ImgH,WIDTH,HEIGHT)
    ImgW=Tw
    ImgH=Th
    CreateControlPoints(nX,nY)  
    CreateCells(nX,nY)
    PW=WIDTH
    PH=HEIGHT
end


function touched(touch)
    
    if touch.state == BEGAN then 
        if touches == 0 then gesture=1 end
        touches = touches +  1 
        end
        
    if (not dothidden) and touch.state==BEGAN and touches==1 and ActiveId == -1 then 
        ActivePoint=nil
        local found=false
        for i=1,nX+1 do
            if found == false then 
                for j=1,nY+1 do
                if found == false then 
                    local z = CpGrid[i][j]
                    local dd = (touch.x - z.c.x) ^ 2 + (touch.y - z.c.y) ^ 2
                    if dd < 300 then 
                        found=true
                        if CpGrid[i][j].movable then ActivePoint = CpGrid[i][j] end
                    end
                    end --endif
                end -- end j
            end -- endif
        end -- i
        if ActivePoint ~= nil then ActiveId=touch.id end   
    end
    
    if touch.state==MOVING and ActiveId==touch.id and ActivePoint ~= nil then 
        ActivePoint.c.x=touch.x
        ActivePoint.c.y=touch.y
        end
        
    if touch.state==ENDED then 
        if ActivePoint==nil and touches == 1 and gesture==1 then
            dothidden = (not dothidden)
            gesture=0
            end
         if ActivePoint == nil and touches==2 and gesture==1 then
            local tmode =displayMode()
            if tmode==STANDARD then
                displayMode(FULLSCREEN)
                else
                displayMode(STANDARD)
                end
            gesture=0
            end
            
        touches = touches - 1
        if touches==0 then gesture=0 end
        ActivePoint=nil
        ActiveId=-1
        end
        
end -- function
    
function ResetPoints()      
    for i=1,nX+1 do
        for j=1,nY+1 do
            local tobj = CpGrid[i][j]
            local tx=tobj.i.x * ImgW
            local ty=tobj.i.y * ImgH
            if tobj.movable then
                tobj.c.x=tx
                tobj.c.y=ty
                end
        end
    end
end
        
function draw()
    
    -- Resize picture for orientation or FullScreen
    if PW ~= WIDTH or PH~=HEIGHT then
       resetSize()
       PW=WIDTH
       PH=HEIGHT
       end
        
    -- change of rows columns 
    if pnX ~= nX or pnY ~= nY then
        InitGrids()
        pnX=nX
        pnY=nY
        end
    
    -- reset to last saved state    
    if DoReset==1 then
        DoReset=0
        ResetPoints()
        end
        
    -- apply saw to control points    
    if DoWave == 1 then
        Dowave=0
        local inc = 0.50
        for i=1,nX+1 do
        for j=1,nY+1 do
            
            local tobj = CpGrid[i][j]
            local tx=tobj.c.x
            local ty=tobj.c.y
            
            if HWave == 0 and nX > 3 and nY > 3 then -- horizontal
                if i%2 == 0 and j > 1 then ty = ty + inc end
            end
            if HWave == 1 and nX > 3 and nY > 3 then -- vertical
                if j%2 == 0 and i > 1 then tx = tx + inc end
            end
            if HWave == 2 and nX > 3 and nY > 3 then -- both
                if i%2 == 0 then tx = tx + inc end
                if j%2 == 0 then ty = ty + inc end
            end
            
            if tx < 0 then tx = 0 end
            if tx > WIDTH then tx = WIDTH end
            if ty < 0 then ty = 0 end
            if ty > HEIGHT then ty = HEIGHT end
            
            if tobj.movable then
                tobj.c.x=tx
                tobj.c.y=ty
                end 
            end
        end
        
        DoWave=0
        end
    
    if Savestate ~= pstate and Savestate == 1 then
        ApplyAndContinue()
        InitGrids()
        Savestate=0
        pstate=Savestate
        end
    
    background(40, 40, 40)
    fill(255,255,255,255)

    for i=1,nX do
        for j=1,nY do
            local z = CpRect[i][j]
            z:draw(theMesh)
        end
    end
    
    for i=1,nX+1 do
    for j=1,nY+1 do
    local z = CpGrid[i][j]
    z:draw()
    end
    end
    
end

I've been working on a project in Codea and I had to code an image selector for my project. Since this functionality is quite generic and it can be useful for other people / projects, I want to share it. Suggestions and bug reports or fixes are welcome. I published the code here:

https://bitbucket.org/jortizg/stripgrid/src

Please explore the Main file for options. I tried to make it quite flexible and generic, so it is not limited to sprites. It can be used to display any content in a grid with the ability to browse it swiping horizontally or vertically.

I am new here and already my eyes are wide open with excitement about this tool. I was wondering if it's possible to disable the anti-aliasing that occurs when you resize an image (for style purposes), either in the app or tinkering around with the runtime library on the mac.

Thanks in advance for your help!

Demo:

Main:

-- Use this function to perform your initial setup
function setup()
    displayMode(STANDARD)
    displayMode(FULLSCREEN)
    screenWidth = 500
    screenHeight = 400
    drawFlag = false
    initFlag = false
    buffer = Buffer()
    xcounter = 0
    result = ""
    errorMsg = ""

    graphTable = {}

    -- Initializing Textfields
    textField = TextField("Formula", 500, 80)
    resultField = TextField("Result", 500,40)
    -- Initializing Buttons
    button = {}
    titles = {"sin()", "cos()", "tan()", "asin()", "acos()", "atan()", "log10()", "log()", "exp()","pow()", "sqrt()", "pi", "+", "-", "*", "/", "%", "(", ")", ",", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0",".", "x", "Solve", "Plot", "Clear","Del", "<==", "==>",}

    counter = 1
    for _, v in pairs (titles) do

        if counter < 13 then
            fill(61, 71, 94, 156)
            r,g,b,a = fill()

        elseif counter >= 13 and counter <= 20 then
            fill(61, 113, 31, 155)
            r,g,b,a = fill()

        else 
            fill(0, 0, 0, 160)
            r,g,b,a = fill()

        end
        table.insert(button,Buttons(v,r,g,b,a,255,255,255,255,15,24))
        counter = counter + 1
    end
end

-- This function gets called once every frame
function draw()
    -- This sets a dark background color 
    background(173, 173, 173, 93)

    initializeScreen()

    drawButtons()
    textField.pos = vec2(centerPnt.x,HEIGHT - HEIGHT*0.1)
    textField:draw() 

    resultField.pos = vec2(centerPnt.x,HEIGHT - HEIGHT*0.18)
    resultField:draw() 

    equationStr = buffer:toString()

    if initFlag then  
        generateEquation()
        if equationStr ~= "y=" then
                initializeTable()
                executeEquation()
                result = y
        else
            errorMsg = "Not a valid equation"
        end
    end
    fontSize(16)
    l,t = textSize(result)
    text(result, resultField.pos.x-resultField.size.x/2+l/2+5,resultField.pos.y )
    text(errorMsg,WIDTH*0.2,HEIGHT-HEIGHT*0.1)

    if drawFlag==true and equationStr ~= "y=" then
       drawCurves()
       spriteMode(CENTER)
       sprite(graph,centerPnt.x,centerPnt.y)
    else
        drawFlag=false
    end 
    buffer:draw()
end

function drawButtons()
    left = WIDTH - WIDTH*0.92
    top = HEIGHT - HEIGHT * 0.265
    counter = 1

    for _, b in pairs(button) do
        b.pos = vec2(left,top)
        b:draw()

        left=left+b.size.x+5
        if counter == 4 then
            counter = 1
            left = WIDTH - WIDTH * 0.92
            top = top - b.size.y-5
        else
            counter = counter + 1
        end
    end
end

function touched (touch)

    for _, b in pairs (button) do
        b:touched (touch)
    end    
end

Buffer:

Buffer = class()

function Buffer:init()
    self.buffer = {}

    self.font = "Inconsolata"
    self.fontSize = 20

    -- x = line, y = pos
    self.cursor = vec2(1,1)

    self.t = 0
    self.cursorBlink = 0
end

function Buffer:setStyle()
    textMode(CORNER)
    font( self.font )
    fill(0, 0, 0, 255)
    fontSize( self.fontSize )
    textWrapWidth(500)
end

function Buffer:cursorToScreen(c)
    -- Get a subset of the buffer
    local lines = table_slice( self.buffer, 1, c.x )
    local l = self.buffer[c.x]

    local upToStr = self:bufferToString(lines)
    local lstr = nil

    if l then
        lstr = table.concat(l)
    end

    pushStyle()

    self:setStyle()

    local lw = 0

    local _,lh = textSize("A")
    local emptyLine = true

    if lstr and lstr ~= "" then
        lw,lh = textSize(string.sub(lstr,1,c.y - 1))
        emptyLine = false
    end

    local pw,ph = textSize(upToStr)

    if emptyLine then
        ph = ph + lh
    end

    popStyle()

    return lw,(ph - lh/2)
end

function Buffer:bufferToString(b)
    local bstrings = {}
    for k,v in pairs(b) do
        table.insert(bstrings, table.concat( b[k] ) )
    end

    return table.concat( bstrings, "\n" )
end

function Buffer:moveCursor(o)
    self.cursor = self.cursor + o

    self.cursor.x = math.max(1, math.min(self.cursor.x, #self.buffer))

    local l = self.buffer[self.cursor.x]
    local y = self.cursor.y

    y = math.max(1, math.min(y, #l + 1))
    self.cursor.y = y
end

function Buffer:insertCharacter(c)
    if c == "x" then
        xcounter = xcounter + 1
    end
    local l = self.buffer[self.cursor.x]

    if l == nil then
        l = {}
        self.buffer[self.cursor.x] = l
    end

    if c == "\n" then
        local start = table_slice(l,1,self.cursor.y)
        local tail = table_slice(l,self.cursor.y+1,#l)


        table[self.cursor.x] = start
        table.insert(self.buffer, self.cursor.x+1, tail)

        self.cursor = vec2( self.cursor.x + 1, 1 )
    elseif c == "Del" then
        if self.cursor.y == 1 then
            -- delete line
            local prevLine = self.buffer[self.cursor.x - 1]

            table.remove(self.buffer, self.cursor.x)

            if prevLine then
                self.cursor = vec2(self.cursor.x - 1, #prevLine + 1)
                table_append( prevLine, l )
            end
        else
            -- delete character

            if (l[self.cursor.y-1] == "x") then
                xcounter = xcounter-1
            end

            table.remove(l, self.cursor.y - 1 )

            self.cursor = vec2(self.cursor.x, self.cursor.y - 1 )
        end
    else
        table.insert(l, self.cursor.y, c)

        self.cursor = vec2( self.cursor.x, self.cursor.y + 1 )

    end

end

function Buffer:draw()
    self.t = self.t + 8 * DeltaTime
    self.cursorBlink = (math.sin(self.t) + 1) * 128

    pushStyle()

    self:setStyle()

    local str = self:toString()
    local w,h = textSize(str)

    pushMatrix()

    translate(textField.pos.x-textField.size.x/2+5,-40)
    text(str, 0, HEIGHT - h)


    -- Draw cursor
    -- Cursor pos x,y
    local cpx,cpy = self:cursorToScreen(self.cursor)

    fill(0, 87, 255, self.cursorBlink)
    rectMode(CENTER)
    rect(cpx,HEIGHT - cpy,5,30)

    popMatrix()
    popStyle()
end

function Buffer:clear()
    self.cursor = vec2(1,1)
    self.buffer = {}
end

function Buffer:toString()
    return self:bufferToString(self.buffer)
end

function Buffer:toStringWithoutActiveLine()
    local bstrings = {}
    for k,v in pairs(self.buffer) do
        if k ~= self.cursor.x then
            table.insert(bstrings, table.concat( self.buffer[k] ) )
        end
    end

    return table.concat( bstrings, "\n" )
end

Other classes and function file is given in the next post as its not allowing to enter more characters in this post.

function setup()
    mx = 0
    my = 0
end

function tileImage(image,movex,movey,iscale)
    local oldScale = scale
    local currentScale = 1
    scale = function( d )
        if d == nil then
            return currentScale
        else
            currentScale = currentScale * d 
            oldScale(d)
        end
    end
    bsmode = spriteMode()
    currentScale = scale()
    bscale = currentScale
    spriteMode(CORNER)
    scale(iscale)
    ssx, ssy = spriteSize(image)
    mx = mx + movex
    my = my + movey
    for y = -1, HEIGHT/ssy/iscale do
        for x = -1, WIDTH/ssx/iscale do
            if mx >= ssx or mx <= -ssx then
                mx = 0
            elseif my >= ssy or my <= -ssy then
                my = 0
            end
            sprite(image, x * ssx+mx, y * ssy+my)
        end
    end
    spriteMode(bsmode)
    scale(bscale)
end

That was easy. But it's still full of bugs and needs improvement. Here's what's on my list:
1. Fix the jolt when repeating the images when moving
2. Fix the problem when you tell it to move mor pixels than the image is
3. Fix the returning to the original scale and sprite mode
4. Madage to contain all the variables within the function
5. Speed up the process. It really slows down the program and even crashes Codea when you use some pixel art.
6. Add option to tell it if it's a block or not and it will automatically offset it correctly and draw the blocks right.

-- snake illusion
-- Herwig Van Marck

function setup()
    print("Change parameters and tap image to recalculate")
    print("Set hide to 1 to go fullscreen, and tap to return")
    parameter("factor",1,10,readProjectData("factor") or 3.37)
    iparameter("init_size",50,HEIGHT,readProjectData("init_size") or 150)
    iparameter("levels",1,30,readProjectData("levels") or 18)
    iparameter("hide",0,1,0)
    hidden=0
    recalc()
end

function touched(touch)
    if (touch.state==BEGAN) then
        if (hidden==0) then
            saveProjectData("factor",factor)
            saveProjectData("init_size",init_size)
            saveProjectData("levels",levels)
            recalc()
        else
            displayMode(STANDARD)
            hidden=0
        end
    end
end

function recalc()
    img=image(init_size*13/6,init_size*13/6)
    local r=init_size
    local size=init_size/24.0
    setContext(img)
    pushMatrix()
    ellipseMode(CENTER)
    translate(init_size*13/12,init_size*13/12)
    fill(255, 255, 255, 255)
    ellipse(0,0,26*init_size/12,26*init_size/12)
    for j=1,levels do
        for i=1,36 do
            fill(0, 0, 0, 255)
            rect(-size,r-2*size,size*2,size*4)
            fill(210, 210, 99, 255)
            ellipse(-size,r,size*2,size*4)
            fill(99, 108, 210, 255)
            ellipse(size,r,size*2,size*4)
            rotate(10)
        end
        rotate(5)
        r,size=r-factor*size,size*r/(r+factor*size)
    end
    popMatrix()
    setContext()
end

-- This function gets called once every frame
function draw()
    if hide==1 then
        displayMode(FULLSCREEN_NO_BUTTONS)
        hidden=1
        hide=0
    end
    
    background(255, 255, 255, 255)

    spriteMode(CENTER)
    pushMatrix()
    for m=1,2 do
        pushMatrix()
        for l=1,math.ceil(HEIGHT/init_size) do
            pushMatrix()
            for k=1,math.ceil(WIDTH/init_size) do
                sprite(img,0,0)                
                translate(26*init_size/12,0)
            end
            popMatrix()
            translate(0,26*init_size/12)
        end
        popMatrix()
        translate(13*init_size/12,13*init_size/12)
    end
    popMatrix()
end

function draw() local i=image(400,400) sprite(i,0,0) end

PS Loving Codea!

Picture http://pic.twitter.com/O2mDYWbw

This may not be what the wiki is intended for but the code along with a lengthy discussion of what it attempts to represent can be found here https://bitbucket.org/TwoLivesLeft/codea/wiki/Limage

Added 3D spheres. Screenshot: https://twitter.com/#!/bortels/status/146358741888024578/photo/1

Plz tell me what u think about it

https://twitter.com/#!/bortels/status/144248682827616259/photo/1

Things I learned:

1) print() is really slow

2) my base64 stuff doesn't work

3) string.gsub does not modify in place (that had me stuck for a few hours)

4) I look DAMN GOOD in a fez. But - I knew that.

5) Image data is really big.

--image save and load
function setup()
    --make image
    myimage = image(10,10)
    for i = 5, 10 do
        for j = 1, 10 do
            myimage:set(i,j,math.random(256),math.random(256),math.random(256),255)
        end
    end   
    --saveimage
    saveimage = myimage.width .. "," .. myimage.height .. ","
    for i = 1, myimage.width do
        for j = 1, myimage.height do
            a,b,c,d = myimage:get(i,j)
            saveimage = saveimage .. a .. "," .. b .. "," .. c .. "," .. d .. ","
        end
    end    
    saveLocalData("x",saveimage)
    --loadimage
    loadimage = readLocalData("x")
    k = 1
    l = string.find(loadimage,",",k)
    lw = string.sub(loadimage,k,l-1)
    lw = lw + 0
    k = l + 1
    l = string.find(loadimage,",",k)
    lh = string.sub(loadimage,k,l-1)
    k = l + 1
    loadedimage = image(lw,lh)
    for i = 1, lw do
        for j = 1, lh do
            l = string.find(loadimage,",",k)
            a = string.sub(loadimage,k,l-1)
            k = l + 1
            l = string.find(loadimage,",",k)
            b = string.sub(loadimage,k,l-1)
            k = l + 1
            l = string.find(loadimage,",",k)
            c = string.sub(loadimage,k,l-1)
            k = l + 1
            l = string.find(loadimage,",",k)
            d = string.sub(loadimage,k,l-1)
            k = l + 1
            loadedimage:set(i,j,a,b,c,d)
        end
    end    
end

function draw()
    rect(0,0,10,10)
    background(0, 0, "095")
    scale(10)
    sprite(myimage,10,10)
    sprite(loadedimage,30,30)
end

Edit: that's not a comment on the image command, it's a comment on this method I wrote.

This is a bridge until a real format can be used.

Is there a way to get an image from the screen? ie. is the screen an image() as well that we can copy to/from? it doesn't seem to be, but maybe I am missing something. What I'd like to do is draw my teh awesome thing, then grab that drawing and blit it around - possible? (If not, I'm gonna be writing some line-drawing routines!)

Time to go write image decoders...