Persistent Data

SwitchedOn

Thanks for this @pianofire - I assume you can have 'many' save files - one for each program yes? Dont want it to be that fuze overwrites another file if you have these functions running in two programs for example?

pianofire

@SwitchedOn Yes there is currently a single file per program. Be aware that if you share the program the contents of this file is shared as well

JonnyLaw

im really going to have to mess with this soon. the most i ever done for save files while i was messing around with Processing was using CSV files

pianofire

Updated with suggestion from @MikeDX

PB____

Awesome. This is very useful and the code looks neat too. Couldn't find bugs.

I do suspect to have found a limitation though (haven't tested it): the current file format probably only supports 9999 entries.
However, I think that's more than enough for anything reasonable. If you need more than that, you probably need to rethink what you're doing, or otherwise need to tweak a lot of code to get it performing for your use case anyway :)

PB____

@pianofire if someone (me, and probably some of the readers) would like to use this in their code, how should they approach it?
Do they need to ask permission, or can they just use it (or not)? And if so, how would you like to be credited about it?

pianofire

@PB____ Please just use it! That's what I wrote it for

PB____

@pianofire Thanks! I will of course put in some form of credit, but this was the reply I was hoping for / kind of expecting :)

pianofire

No problem. Feel free to improve on it too!

PB____

I've noticed that you don't declare your function scoped variables.

It is likely that someone uses a variable called i in their for loop. If they do this in the global scope and use getValue within that for loop, the i value of the global varible i would be changed by getValue. This could be fixed as follows:

// Get the value for the specified key
function getValue( key )
    var i = 0
    var result = "Undefined"
    var found = false
    while i < len(store) and !found loop
        if store[i].key == key then
            found = true
            result = store[i].value
        else
            i += 1
        endif
    repeat
    if found then
        if store[i].type == "int" then
            result = int( result )
        endif
        if store[i].type == "str" then
            result = str( result )
        endif
        if store[i].type == "float" then
            result = float( result )
        endif
    endif
return result

I now var is not a keyword (you could use int in stead), it's a personal preference, mainly since boolean found = false doesn't appear to be technically correct either.

LinkCraft

Wait I’m confused is this so you can access data from any program

PB____

@LinkCraft02 I think you might have misread "a way of persisting data across programs" in stead of " a way of persisting data across program runs" ?

I think you can only access the file that belongs to project you are running.

pianofire

I have updated this in line with the @PB____ recommendations.

Also it now supports vector types

password1

@pianofire please post a usage example.

pianofire

There are some examples in the download:

// Initialize values or load from the store
if !loadStore() then // init on first run
    setValue( "test1", 99, "int" )
    setValue( "test2", "", "str" )
    setValue( "test3", pi, "float" )
    setValue( "test4", { 0, 1, 2, 3 }, "vector" )
endif

// Get values from store
test1 = getValue( "test1" )
test2 = getValue( "test2" )
test3 = getValue( "test3" )
test4 = getValue( "test4" )

// Show current values
finished = false
while !finished loop
    clear()
    c = controls( 0 )
    printAt( 0, 0, "Press X to exit" )
    printAt( 0, 1, "test1 : ", test1 )
    printAt( 0, 2, "test2 : ", test2 )
    printAt( 0, 3, "test3 : ", test3 )
    printAt( 0, 4, "test4 : ", test4 )
    finished = c.x
    update()
repeat

// Change values
test1 = test1 + 1
test2 = test2 + "wibble"
test3 = test3 * 2
test4 = { test4.x + 1, test4.y * 2, test4.z - 1, test4.w / 2 }

// Save current values to store
setValue( "test1", test1, "int" )
setValue( "test2", test2, "str"  )
setValue( "test3", test3, "float" )
setValue( "test4", test4, "vector" )

saveStore() // save store to file

PB____

@pianofire I can't seem to download from the code NDZQHDNDNN anymore.
I did evolve the code to my preferences anyway (since you're in my friends-list, you could check it out on NDSF6DND1Z, it's part of my template project that I intend to use for my new projects)

pianofire

@PB____ Sorry my fault I unshared it so the code changed. The new code is FPH33MNDNN

I have had a quick look at what you have done and it looks very impressive. That looks like an incredible amount of work! I will update my example using your code if that is OK (with credit of course)

PB____

@pianofire Thanks :-) I hope the work pays off. Since it's my template project, I hope that the work I put in it, will benefit all my future projects, so as a net result, it saves me work overall :)
And of course I'm OK with it if you can improve the file storage example based on my code :-). I'd like to clarify my thought process about how I start the file:

// file format (to enable compatibility check)
file_writeLine(file, "PB")
// reserved for updates to the file format:
file_writeLine(file, 0)

Currently projects can only have one file, and it's not possible to share files across different projects. But still I thought it was a good idea to mark a file format at the start of the file, just in case the mentioned limitations change in the future. Of course this means that I hope that other people won't mark their files with the same opening as I did, to prevent potential errors in the future :-)

The second line (0) is to mark a version of the format. In case people download an updated version of a program, and I need to check how to handle the format of an older file (in case the download mechanism doesn't include saved files in the future, since it has been suggested that that behavior is a bug).

waldron

could this be simplified to save a sprites location using maps

pianofire

@waldron I am not sure what you mean. It can already save vectors (such as a sprite position). There is one in the example above