I was doing an app that reads qrcodes, and I was wondering how can I avoid that anyone with a qrcode generator could clone one of my qrcode.
I know I can't avoid the duplication (especially if you use a small number) but I was wondering if there is any approach I could use to reduce this or add an app validation to avoid this.
Thanks in advance
Either use a one-time-use id where the first person to access your URL wins, or just accept it as free advertising. If you really wanted to go to the trouble I guess you could probably print a watermark that obscures the code so it is unreadable, somewhat like the security features most checks have, but this really sounds like an XY problem.
Think about the problem you're really trying to solve and how so solve it. QR codes themselves are just as reproducible as emailing someone a link or giving someone a piece of paper with a word on it.
Related
I'm looking to create this project in processing, however, I'm finding the terminology a bit hard. I'm not sure how to call the effect where the line is staying permanently throughout the song to 'draw' the music data.
I would appreciate any guidance on what tutorials I could look at or an answer from someone.
My aim is to create something as close to this as possible:
https://www.youtube.com/watch?v=Bb5PTitqtlc&t=58s
Stack Overflow isn't really designed for general "how do I do this" type questions. It's for specific "I tried X, expected Y, but got Z instead" type questions. But I'll try to help in a general sense:
You need to break your problem down into smaller pieces and then take those pieces on one at a time. Write down exactly what you want to happen, in English, and that will be an algorithm that you can think about implementing with code.
Get something simple working. Can you write a simple sketch that plays a song? Then work your way forward in small steps. Can you write a simple sketch that prints out some numeric values based on the song that's playing? Separately from that, can you create a very simple visualization using hard-coded numbers? Get all of that working separately before you think about combining them into a sketch that shows a visualization based on a song that's playing.
Then if you get stuck, you can post a more specific question along with a MCVE. Good luck.
I wrote some code that processes 135,000 books. I just got word from my retailer that 983 books seem to have an issue and is blaming my code for "screwing up" his inventory. I have a friend on the inside that says that there has been an on going issue with his inventory and it doesnt look to be me.
I'm thinking that if the issue was my code, more than .73% (983/135,000) of the data would be affected. How do I reply to him in mathematical terms to disprove his theory that it was my code?
Maybe exactly 983 books have a cedilla. Or Japanese characters. Or diphthongs.
I don't think there's any way you can use statistics here that won't cause statisticians to cringe.
Why don't you just offer a 0.73% discount to your fee, based on the outcome? :-)
Or, offer to fix the problem, meaning that they'll have to provide the information as to why they think they're screwed up.
In other words, make them specify what "screwed up" actually means. Do they not open in the reader? Do they open but characters or formatting are incorrect? Do they "brick" the reading devices?
Without real information, there's little you can do.
I am applying A* (and IDA*) search with manhattan heuristic for finding solution to 15-puzzle problem.
Using the fact that i dont want an optimal solution for the problem how can i can speed up the search as the current routine is too slow.
Well, it's not exactly a solution, but it might help. Once I've been working for a HOG game with that same puzzle as a minigame and it turned much easier to generate a problem, than find a solution.
What I mean is, we can turn a solved puzzle into unsolved by randomly moving "window" according to rules. And logging each field position for future use. Then we let user play a bit and if she gives up, we can solve a puzzle for her easily by finding the common position in user and our log. We just play back via user log to the common position and back from it to the solved position via ours log.
Of course, this is a hack and not a real solution, but it works fine in gamedev. And not only for this particular game. Most repositioning puzzles can be "solved" this way.
I am new to processing, i found it by searching for "draw with coding" , and i tried it, seems every time i modify the code, i have to stop and render again to get the final result
Is there any way to get updated graph without re-rendering? that can be much more convenient for creating simple figures.
if not, is there any alternative to processing that can draw a graph with coding?
I've used Tikz in Latex, but that is just for Latex, I want something that can let me draw a figure by coding, I've suffered enough though using software like coreldraw, it lacks the fundamental elegance of coding..
thanks alot！
Please have a look at the FluidForms libraries.
easy to setup
documentation and video tutorials
as long as you don't run into exceptions, live code comfortably
if you prefix public variables with param you also get sliders for free :)
Do check out the video tutorials, especially this one:
Also, if using Python isn't a problem I recommend having a look at:
NodeBox
Field
Python is a brilliant scripting language - which makes prototyping/'live coding' easy(although it can be compiled and it also plays nicely with c/c++) and is easy to pick up and a joy to use.
In Processing, you must re-run your program to see the changes (graphically), unless you write code to receive input from the user to dynamically adjust what you are drawing. For creating user interfaces there's for example the controlP5 library (http://www.sojamo.de/libraries/controlP5/).
It doesn't support "live coding" (at least that I know of).
You must re-run the code to see the new result.
If Live coding is what you're looking for, check out Fluxus (http://www.pawfal.org/fluxus/) or Impromptu (http://en.wikipedia.org/wiki/Impromptu_(programming_environment)
I'm trying to program a Webpage, which allows to edit a text document simultaneously.
To program something like a Chat in Node.js is not very difficult, but working on the same text makes it kinda tricky.
I thought about sending the char position and the changes characters, but if someone types something previous to the change, the change would be placed on the wrong position.
What's the best way to exchange Modifications between my clients?
You should use Socket.io to have make your Real-Time application.
I just founded a nice blog article which speaks about real time edition, see here.
It's also providing a link to the github project and to an open source online editor project.
Take a look and try to understand how they do stuff like this, good luck !
Two people cannot be manipulating the same object at the same time from a different place. You basically have two choices.
1. Let them take turns with the object
2. duplicate it if they both want it, but that doesnt sound like it would end well