I write code and play games and stuff. My old username from reddit and HN was already taken and I couldn’t think of anything else I wanted to be called so I just picked some random characters like this:

>>> import random
>>> ''.join([random.choice("abcdefghijklmnopqrstuvwxyz0123456789") for x in range(5)])
'e0qdk'

My avatar is a quick doodle made in KolourPaint. I might replace it later. Maybe.

日本語が少し分かるけど、下手です。

Alt: [email protected]

  • 2 Posts
  • 68 Comments
Joined 1 year ago
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Cake day: September 22nd, 2023

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  • Have you tried Resonance? It’s a mystery adventure game set in modern times where you play as four different characters whose stories interconnect. It’s been a while since I played it (a decade or so?) but I remember that it had an interesting game mechanic that let you use memories like items in various interactions, as well as a number of puzzles that I rather liked the design of.



  • It’s not a GUI library, but Jupyter was pretty much made for the kind of mathematical/scientific exploratory programming you’re interested in doing. It’s not the right tool for making finished products, but is intended for creating lab notebooks that contain executable code snippets, formatted text, and visual output together. Given your background experience and the libraries you like, it seems like it’d be right up your alley.


  • The Wikipedia article for hqx points out that an implementation exists as a filter in ffmepg.

    You can run a command line conversion of e.g. a PNG -> PNG using hqx upscaling like: ffmpeg -i input.png -filter_complex hqx=4 output.png

    The =4 is for 4x upscaling. The implementation in my version of ffmpeg supports 2x, 3x, and 4x upscaling.

    As a quick and dirty way to get semi-live preview, you can do the conversion with make and use watch make to try to rebuild the conversion periodically. (You can use the -n flag to increase the retry rate if the default is too long to wait.) make will exit quickly if the file hasn’t changed. Save the image in your editor and keep an image viewer that supports auto-reload on change open to see “live” preview of the output. (e.g. eog can do it, although it won’t preserve size of the image – at least not in the copy I have, anyway; mine’s a bit old though.)

    Sample Makefile:

    output.png : input.png Makefile
    	ffmpeg -y -i input.png -filter_complex hqx=4 output.png
    
    

    Note the -y option to tell ffmpeg to overwrite the file; otherwise it will stop to ask you if you want to overwrite the file every time you save, and in case you’re not familiar with Makefiles, you need a real tab (not spaces) on the line with the command to run.

    ffmpeg also appears to support xbr (with =n option as well) and super2xsai if you want to experiment with those too.

    I’m not sure if this will actually do what you want artistically, but the existing implementations in ffmpeg makes it easy to experiment with.



  • Can Z3 account for lost bits? Did it come up with just one solution?

    It gave me just one solution the way I asked for it. With additional constraints added to exclude the original solution, it also gives me a second solution – but the solution it produces is peculiar to my implementation and does not match your implementation. If you implemented exactly how the bits are supposed to end up in the result, you could probably find any other solutions that exist correctly, but I just did it in a quick and dirty way.

    This is (with a little clean up) what my code looked like:

    solver code
    #!/usr/bin/env python3
    
    import z3
    
    rand1 = 0.38203435111790895
    rand2 = 0.5012949781958014
    rand3 = 0.5278898433316499
    rand4 = 0.5114834443666041
    
    def xoshiro128ss(a,b,c,d):
        t = 0xFFFFFFFF & (b << 9)
        r = 0xFFFFFFFF & (b * 5)
        r = 0xFFFFFFFF & ((r << 7 | r >> 25) * 9)
        c = 0xFFFFFFFF & (c ^ a)
        d = 0xFFFFFFFF & (d ^ b)
        b = 0xFFFFFFFF & (b ^ c)
        a = 0xFFFFFFFF & (a ^ d)
        c = 0xFFFFFFFF & (c ^ t)
        d = 0xFFFFFFFF & (d << 11 | d >> 21)
        return r, (a, b, c, d)
    
    a,b,c,d = z3.BitVecs("a b c d", 64)
    nodiv_rand1, state = xoshiro128ss(a,b,c,d)
    nodiv_rand2, state = xoshiro128ss(*state)
    nodiv_rand3, state = xoshiro128ss(*state)
    nodiv_rand4, state = xoshiro128ss(*state)
    
    z3.solve(a >= 0, b >= 0, c >= 0, d >= 0,
      nodiv_rand1 == int(rand1*4294967296),
      nodiv_rand2 == int(rand2*4294967296),
      nodiv_rand3 == int(rand3*4294967296),
      nodiv_rand4 == int(rand4*4294967296)
      )
    
    

    I never heard about Z3

    If you’re not familiar with SMT solvers, they are a useful tool to have in your toolbox. Here are some links that may be of interest:

    Edit: Trying to fix formatting differences between kbin and lemmy
    Edit 2: Spoiler tags and code blocks don’t seem to play well together. I’ve got it mostly working on Lemmy (where I’m guessing most people will see the comment), but I don’t think I can fix it on kbin.



  • If I understand the problem correctly, this is the solution:

    solution

    a = 2299200278
    b = 2929959606
    c = 2585800174
    d = 3584110397

    I solved it with Z3. Took less than a second of computer time, and about an hour of my time – mostly spent trying to remember how the heck to use Z3 and then a little time debugging my initial program.


  • What I’d do is set up a simple website that uses a little JavaScript to rewrite the date and time into the page and periodically refresh an image under/next to it. Size the image to fit the remaining free space of however you set up the iPad, and then you can stick anything you want there (pictures/reminder text/whatever) with your favorite image editor. Upload a new image to the server when you want to change the note. The idea with an image is that it’s just really easy to do and keeps the amount of effort to redo layout to a minimum – just drag stuff around in your image editor and you’ll know it’ll all fit as expected as long as you don’t change the resolution (instead of needing to muck around with CSS and maybe breaking something if you can’t see the device to check that it displays correctly).

    There’s a couple issues to watch out for – e.g. what happens if the internet connection/server goes down, screen burn-in, keeping the browser from being closed/switched to another page, keeping it powered, etc. that might or might not matter depending on your particular circumstances. If you need to fix all that for your circumstances, it might be more trouble than just buying something purpose built… but getting a first pass DIY version working is trivial if you’re comfortable hosting a website.

    Edit: If some sample code that you can use as a starting point would be helpful, let me know.


  • e0qdk@kbin.socialtoAsklemmy@lemmy.ml***
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    10 months ago

    My guess is that if browsers as we know them weren’t invented, HyperCard would’ve become the first browser eventually. No idea where things would progress from there or if it’d have been better or worse than the current clusterfuck. Maybe we’d all be talking about our “web stacks” instead of websites, and have various punny tools like “pile” and “chimney” and “staplr”. Perhaps PowerPoint would’ve turned into a browser to compete with it.

    If browsers were invented but JavaScript specifically was not, we’d probably all be programming sites in some VB variant like VBScript (although it might be called something different).





  • Didn’t the GDPR have a data portability rule requiring that sites provide users the ability to easily export their own data? Does that not apply to Lemmy for some reason – or, am I misremembering it? (I remember account data download being a big deal a while back on reddit, but it’s been a few years…)