I updated this code, which asks you if you want to trim the layers or not, and also if you add $ to your layer, e.g. $BG → background layer (applied under every image).
PS. just open the .lua file in note pad and replace the whole code.
Thanks FeelPr
"script"
app.transaction(function()
–[[
Export By Group (Preserve Positions, Optional Trim)
Author: Feel & ChatGPT
License: CC BY-NC-SA 4.0
]]
local spr = app.activeSprite
if not spr then return app.alert(“No active sprite”) end
if spr.filename == “” then return app.alert(“Please save your .aseprite file first”) end
– Ask if user wants trimming
local doTrim = app.alert {
title = “Trim Images?”,
text = “Do you want to trim transparent borders from exported images?”,
buttons = { “Yes”, “No” }
} == 1
– Find export path layer
local exportRoot = nil
local percentLayers = {}
for _, layer in ipairs(spr.layers) do
if layer.name:sub(1,1) == “%” then
table.insert(percentLayers, layer)
end
end
if #percentLayers == 0 then
return app.alert(“No export path layer found. Create a layer like: %D:/Path/”)
elseif #percentLayers > 1 then
return app.alert(“Only one export path layer (%) allowed.”)
end
exportRoot = percentLayers[1].name:sub(2)
local lastChar = exportRoot:sub(-1)
if lastChar ~= “/” and lastChar ~= “\” then
return app.alert(“Export path must end with slash or backslash.”)
end
if exportRoot:find(“\”) and not exportRoot:find(“\\”) then
return app.alert(“Windows paths must use double backslashes.”)
end
– Find background layer
local backgroundLayer = nil
for _, layer in ipairs(spr.layers) do
if layer.name:sub(1,1) == “$” and layer.isImage then
if backgroundLayer then
return app.alert(“Only one background layer ($) allowed.”)
end
backgroundLayer = layer
end
end
– Create folders
local function ensureDir(path, cache)
if cache[path] then return end
local sep = package.config:sub(1,1)
if sep == “\” then
os.execute(‘if not exist "’ .. path .. ‘" mkdir "’ .. path .. ‘"’)
else
os.execute(‘mkdir -p "’ .. path .. ‘"’)
end
cache[path] = true
end
– Setup log
local logPath = exportRoot .. “= Export-Logs/”
local createdPaths = {}
ensureDir(logPath, createdPaths)
local logFile = io.open(logPath .. “export-log.txt”, “a”)
if not logFile then return app.alert(“Cannot write export log”) end
local date = os.date(“[%Y-%m-%d %H:%M]”)
logFile:write(date .. "\nExport from: " .. (spr.filename or “(unsaved)”) .. “\n\n”)
local exportCount, skippedCount = 0, 0
local function isGroup(layer)
local ok, children = pcall(function() return layer.layers end)
return ok and children ~= nil
end
local function getTrimBounds(image)
local r = image.bounds
local left, top, right, bottom = r.x + r.width, r.y + r.height, r.x, r.y
local found = false
for y = r.y, r.y + r.height - 1 do
for x = r.x, r.x + r.width - 1 do
if image:getPixel(x, y) >> 24 > 0 then
if x < left then left = x end
if y < top then top = y end
if x > right then right = x end
if y > bottom then bottom = y end
found = true
end
end
end
if not found then return nil end
return {x=left, y=top, w=right-left+1, h=bottom-top+1}
end
– Export one layer or flattened group
local function exportCel(image, cel, name, folderPath)
local bounds = nil
if backgroundLayer then
for _, bgCel in ipairs(backgroundLayer.cels) do
if bgCel.frameNumber == cel.frameNumber then
bounds = getTrimBounds(bgCel.image)
break
end
end
end
if not bounds then bounds = getTrimBounds(image) end
if not bounds then
logFile:write(“→ Skipped: fully transparent\n”)
skippedCount = skippedCount + 1
return
end
local finalW, finalH = spr.width, spr.height
local offset = Point(0, 0)
if doTrim then
finalW, finalH = bounds.w, bounds.h
offset = Point(-bounds.x, -bounds.y)
end
local exportImage = Image(finalW, finalH, image.colorMode)
if backgroundLayer then
for _, bgCel in ipairs(backgroundLayer.cels) do
if bgCel.frameNumber == cel.frameNumber then
exportImage:drawImage(bgCel.image, offset + bgCel.position)
break
end
end
end
exportImage:drawImage(image, offset + cel.position)
ensureDir(folderPath, createdPaths)
local newSprite = Sprite(finalW, finalH)
newSprite:newCel(newSprite.layers[1], cel.frameNumber, exportImage, Point(0, 0))
local filename = folderPath .. name .. “.png”
newSprite:saveCopyAs(filename)
newSprite:close()
logFile:write(string.format(“→ Exported: %s (%dx%d)\n”, filename, finalW, finalH))
exportCount = exportCount + 1
end
local function exportGroupImage(group, name, folderPath)
local function findLayerIndex(container, target)
for i, layer in ipairs(container.layers) do
if layer == target then return i, container end
if layer.isGroup then
local idx, parent = findLayerIndex(layer, target)
if idx then return idx, parent end
end
end
end
local groupIndex, parent = findLayerIndex(spr, group)
if not groupIndex or not parent then
logFile:write(“→ Error: group index not found\n”)
skippedCount = skippedCount + 1
return
end
app.range.layers = { group }
app.command.FlattenLayers()
local flattenedLayer = parent.layers[groupIndex]
if not flattenedLayer or not flattenedLayer.isImage then
logFile:write(“→ Error: flatten failed\n”)
skippedCount = skippedCount + 1
return
end
for _, cel in ipairs(flattenedLayer.cels) do
exportCel(cel.image, cel, name, folderPath)
return
end
end
local function exportLayer(layer, folderPath)
if not layer.isVisible or layer.name:find(“#”) then
logFile:write("→ Skipped: " .. layer.name .. “\n”)
skippedCount = skippedCount + 1
return
end
for _, cel in ipairs(layer.cels) do
exportCel(cel.image, cel, layer.name, folderPath)
return
end
end
– Recursive walker
local function walk(container, parentGroup)
for _, layer in ipairs(container.layers) do
local name = layer.name or “(unnamed)”
local isIgnored = name:find(“#”) or name:sub(1,1) == “%” or name:sub(1,1) == “$”
if isIgnored then
logFile:write("→ Skipped: " .. name .. "\n")
skippedCount = skippedCount + 1
elseif not layer.isVisible then
logFile:write("→ Skipped (not visible): " .. name .. "\n")
skippedCount = skippedCount + 1
elseif isGroup(layer) then
if name:sub(1,1) == "@" then
local cleanName = name:sub(2)
local folderPath = exportRoot .. (parentGroup and parentGroup .. "/" or "")
exportGroupImage(layer, cleanName, folderPath)
else
local newGroupPath = parentGroup and (parentGroup .. "/" .. name) or name
walk(layer, newGroupPath)
end
elseif layer.isImage then
local folderPath = exportRoot .. (parentGroup and parentGroup .. "/" or "")
exportLayer(layer, folderPath)
else
logFile:write("→ Skipped (unknown type): " .. name .. "\n")
skippedCount = skippedCount + 1
end
end
end
walk(spr, nil)
logFile:write(“\nTotal exported : " .. exportCount .. “\n”)
logFile:write(“Total skipped : " .. skippedCount .. “\n”)
logFile:write(”------------\n\n”)
logFile:close()
app.alert(“Export complete: " .. exportCount .. " exported, " .. skippedCount .. " skipped.”)
end)
app.undo()
Export By Group (Recursive) — Aseprite Script
What this script does
Recursively walks all groups and sub-groups
Define export path inside your Aseprite file (no script editing needed !)
How it works:
Set your export path inside your Aseprite file
Rules for the export path layer:Invalid:
Example Aseprite structure
GitHub – Export By Group (Recursive)
