square to isometric-side.lua

--left side (side)
--the pixels will go down diagonally

local originPoint

-- bail if there's no active sprite
local sprite = app.activeSprite
local currentCel = app.activeCel
if not sprite then 
    print("No sprite")
    return 
end

-- bail if nothing's selected
local selection = sprite.selection
if selection.isEmpty then 
    print("Missing selection")
    return 
end

if selection.bounds.width % 2 ~= 0 then
    print("The width must be an even number")
end

function CopyImage(fromImage, rect)
    local pixelsFromSelection = fromImage:pixels(rect)
    local selectedImage = Image(rect.width, rect.height + rect.width/2)
    local yOffset = 0
    
    for it in pixelsFromSelection do
      local pixelValue = it()
      local newX = it.x - rect.x
      local newY = it.y - rect.y
      if(newX % 2 == 0) then
        yOffset = yOffset + 1
      end

      if(newX == 0) then
        yOffset = 0
      end
      selectedImage:putPixel(newX, newY + yOffset, pixelValue)
    end
    return selectedImage
end

originPoint = selection.origin
local currentImage = Image(sprite.width, sprite.height)
currentImage:drawSprite(sprite, currentCel.frameNumber)
local selectedImage = CopyImage(currentImage, selection.bounds)

local outputLayer = sprite:newLayer()
outputLayer.name = "IsometricSide"
local outputSprite = outputLayer.sprite
local cel = sprite:newCel(outputLayer, currentCel.frameNumber)
local backToOriginImage = Image(outputSprite.width,outputSprite.height)
--backToOriginImage:drawImage(newIso, originPoint)
backToOriginImage:drawImage(selectedImage, originPoint)
cel.image = backToOriginImage