pixelsort_anim.lua

require "gd"

local base = gd.createFromJpeg("frm/frm1.jpg")
local black = base:colorAllocate(0, 0, 0)
local sizex, sizey = base:sizeXY()
local frame = gd.create(sizex, sizey)

function lum(c)
    local r = base:red(c)
    local g = base:green(c)
    local b = base:blue(c)
    return (r+g+b)/3
end

function sortfrmv(base, sizex, sizey, p2p, threshold, ord)
    local out = gd.createTrueColor(sizex, sizey)
    for x = 1, sizex do
        local startsort = 1
        local sortc = base:getPixel(x, 1)
        local sortw = lum(sortc)
        local sortlist = {{c = sortc, w = sortw}}
        for y = 2, sizey do
            local color = base:getPixel(x, y)
            local w = lum(color)
            if (p2p and math.abs(w-sortlist[#sortlist].w) > threshold)
            or (not p2p and math.abs(w-sortw) > threshold) or y == sizey then
                if ord == 'inc' then
                    table.sort(sortlist, function(a, b) return a.w < b.w end)
                elseif ord == 'dec' then
                    table.sort(sortlist, function(a, b) return a.w > b.w end)
                else
                    if sortlistside(sortlist) < 0 then
                        table.sort(sortlist, function(a, b) return a.w < b.w end)
                    else
                        table.sort(sortlist, function(a, b) return a.w > b.w end)
                    end
                end
                for ly = 1, #sortlist do
                    out:setPixel(x, startsort+ly-1, sortlist[ly].c)
                end
                startsort = y
                sortw = w
                sortlist = {{c = color, w = w}}
            else
                table.insert(sortlist, {c = color, w = w})
            end
        end
    end
    return out
end

function sortfrmh(base, sizex, sizey, p2p, threshold, ord)
    local out = gd.createTrueColor(sizex, sizey)
    for y = 1, sizey do
        local startsort = 1
        local sortc = base:getPixel(1, y)
        local sortw = lum(sortc)
        local sortlist = {{c = sortc, w = sortw}}
        for x = 2, sizex do
            local color = base:getPixel(x, y)
            local w = lum(color)
            if (p2p and math.abs(w-sortlist[#sortlist].w) > threshold)
            or (not p2p and math.abs(w-sortw) > threshold) or x == sizex then
                if ord == "inc" then
                    table.sort(sortlist, function(a, b) return a.w < b.w end)
                elseif ord == "dec" then
                    table.sort(sortlist, function(a, b) return a.w > b.w end)
                else
                    if sortlistside(sortlist) < 0 then
                        table.sort(sortlist, function(a, b) return a.w < b.w end)
                    else
                        table.sort(sortlist, function(a, b) return a.w > b.w end)
                    end
                end
                for lx = 1, #sortlist do
                    out:setPixel(startsort+lx-1, y, sortlist[lx].c)
                end
                startsort = x
                sortw = w
                sortlist = {{c = color, w = w}}
            else
                table.insert(sortlist, {c = color, w = w})
            end
        end
    end
    return out
end

frame:gifAnimBegin("out.gif", false, 0)
for frm = 1, 50 do
    base = gd.createFromJpeg("frm/frm"..frm..".jpg")
    local th = frm-1
    local sorted = sortfrmv(base, sizex, sizey, true, th, 'dec')
    frame = sorted:createPaletteFromTrueColor(true, 40)
    frame:gifAnimAdd("out.gif", true, 0, 0, 8, gd.DISPOSAL_NONE)
    print("frame:", frm, "threshold:", th)
end
gd.gifAnimEnd("out.gif")