Embedded pictures

steve64

May I embed picture files in a LuaRT-compiled EXE and load them as images in ui.Picture widgets ?

Samir

Hi steve64,

Yes that's one of the main feature of rtc, the Lua script to executable compiler.
You can choose a directory to embed its content within your executable, along with your Lua script.

Once compiled, you can access it through the global embed module, that has a File object to access the embedded files.
Here is the documentation to rtc : [Login to see the link]

So, when you set the image file for the ui.Picture object, use embed.File("filename") as parameter

taki

Samir Hello, I came here looking to understand how the rtc tool works, and I noticed that you mention the embed.File() method, so I had a doubt, this method does not seem to be mentioned anywhere in the documentation or on github, the embed module has other methods that are not documented?

steve64

I tried this approach but still I'm not able to get the embedded image.
This is an example that on my side is not working:

local ui = require 'ui'

win = ui.Window('Embedded Image', 'fixed', 200, 100)
--local pic = ui.Picture(win, "zynq_102_small.png", 20, 20) - OK
f = embed:File("zynq_104_small.png")
ui.info(type(f))
local pic = ui.Picture(win, f.name, 20, 20)  -- KO
win:show()
while win.visible do ui.update() end

I built the exe adding a 'data' subfolder contaiing the png image file.

Samir

You should provide the File instance directly to the Picture constructor or the file fullpath, not the file name :

local ui = require 'ui'

win = ui.Window('Embedded Image', 'fixed', 200, 100)
--local pic = ui.Picture(win, "zynq_102_small.png", 20, 20) - OK
f = embed:File("zynq_104_small.png")
ui.info(type(f))
local pic = ui.Picture(win, f, 20, 20)  -- KO
win:show()
while win.visible do ui.update() end

steve64

I already tried that, but on my side is not working.
The window is shown, the info dialog print 'string' but no picture is displayed.
Maybe the exe is not properly built ?
I'm using this build command:
rtc -s -w -o embimg.exe data embimg.wlua

ruby

Picture does not support File,

you can use quickrt.exe to reproduce this:


► ui = require "ui"

► f = sys.File('test')

► type(f)
"File"

► win = ui.Window("Picture.constructor() sample", 340, 180)

► type(win)
"Window"

► p = ui.Picture(win, f)
>>> in method 'Picture.constructor' (string expected, got File)

►

obviously Picture does not support File, only string is expected

but the document says that:
[Login to see the link]

image: A File object or a filename string, representing the image to be loaded.

so either the doc is incorrect or the code is incorrect

Samir

It should accept File instances, it's a bug.

For the embedded Files access, the rtc command Line you are using puts the content of the data directory, so it should find the PNG file. So use f.fullpath instead of f.name

I will investigate this, but it should work (the LuaRT setup executable uses this method to access embedded Files)

Samir

Update
I've found the bug : you are right, actually the Picture object constructor expects a string (it is not expected, as it should accept File object instances too).

The Picture.load() method is working as expected (it accepts Files or strings)

steve64

Ok, the following is now working on my side:

local ui = require 'ui'
win = ui.Window('Embedded Image Demo', 'fixed', 400, 200)
f = embed.File("zynq_102_small.png")
local pic = ui.Picture(win, '', 20, 20)  -- KO
pic:load(f)
win:show()
while win.visible do ui.update() end

Samir

Thank you for the feedback 👍

Samir

Hi Taki,

You are right the embed module has no specific documentation, because :

This module is only available in compiled LuaRT programs
This module has only two members that are already documented (the embed.File object that wraps a sys.File object to access embeded files, and a embed.zip property, a Zip instance that contains all embededded content)

Those informations are given on the dedicated documentation page for rtc, at the bottom of this page :
[Login to see the link]

taki

You're right, sorry about that, I just had a hard time figuring out how to access embedded files without having to extract to memory.

Samir

This mean that a tutorial is needed 😉