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Search - "buffers"
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We had a Commodore64. My dad used to be an electrical engineer and had programs on it for calculations, but sometimes I was allowed to play games on it.
When my mother passed away (late 80s, I was 7), I closed up completely. I didn't speak, locked myself into my room, skipped school to read in the library. My dad was a lovely caring man, but he was suffering from a mental disease, so he couldn't really handle the situation either.
A few weeks after the funeral, on my birthday, the C64 was set up in my bedroom, with the "programmers reference guide" on my desk. I stayed up late every night to read it and try the examples, thought about those programs while in school. I memorized the addresses of the sound and sprite buffers, learnt how programs were managed in memory and stored on the casette.
I worked on my own games, got lost in the stories I was writing, mostly scifi/fantasy RPGs. I bought 2764 eproms and soldered custom cartridges so I could store my finished work safely.
When I was 12 my dad disappeared, was found, and hospitalized with lost memory. I slipped through the cracks of child protection, felt responsible to take care of the house and pay the bills. After a year I got picked up and placed in foster care in a strict Christian family who disallowed the use of computers.
I ran away when I was 13, rented a student apartment using my orphanage checks (about €800/m), got a bunch of new and recycled computers on which I installed Debian, and learnt many new programming languages (C/C++, Haskell, JS, PHP, etc). My apartment mates joked about the 12 CRT monitors in my room, but I loved playing around with experimental networking setups. I tried to keep a low profile and attended high school, often faking my dad's signatures.
After a little over a year I was picked up by child protection again. My dad was living on his own again, partly recovered, and in front of a judge he agreed to be provisory legal guardian, despite his condition. I was ruled to be legally an adult at the age of 15, and got to keep living in the student flat (nation-wide foster parent shortage played a role).
OK, so this sounds like a sobstory. It isn't. I fondly remember my mom, my dad is doing pretty well, enjoying his old age together with an nice woman in some communal landhouse place.
I had a bit of a downturn from age 18-22 or so, lots of drugs and partying. Maybe I just needed to do that. I never finished any school (not even high school), but managed to build a relatively good career. My mom was a biochemist and left me a lot of books, and I started out as lab analyst for a pharma company, later went into phytogenetics, then aerospace (QA/NDT), and later back to pure programming again.
Computers helped me through a tough childhood.
They awakened a passion for creative writing, for math, for science as a whole. I'm a bit messed up, a bit of a survivalist, but currently quite happy and content with my life.
I try to keep reminding people around me, especially those who have just become parents, that you might feel like your kids need a perfect childhood, worrying about social development, dragging them to soccer matches and expensive schools...
But the most important part is to just love them, even if (or especially when) life is harsh and imperfect. Show them you love them with small gestures, and give their dreams the chance to flourish using any of the little resources you have available.22 -
My mom died when I was 7, after which my dad bought me a Commodore 64 so I had something to lose myself in during the mourning process.
I learned everything about that system, from my first GOTO statement to sprite buffers, to soldering my own EPROM cartridges. My dad didn't deal with the loss so well, and became a missing person 5 years later when I was 12.
I got into foster care with a bunch of strict religious cultists who wouldn't allow electronics in the house.
So I ran away at 14, sub-rented a closet in a student apartment using my orphan benefits and bought a secondhand IBM computer. I spent about 16 hours a day learning about BSD and Linux, C, C++, Fortran, ADA, Haskell, Livescript and even more awful things like Visual Basic, ASP, Windows NT, and Active Directory.
I faked my ID (back then it was just a laminated sheet of paper), and got a job at 15-pretending-to-be-17 at one of the first ISPs in my country. I wrote the firmware and admin panel for their router, full of shitty CGI-bin ASP code and vulnerabilities.
That somehow got me into a job at Microsoft, building the MS Office language pack for my country, and as an official "conflict resolver" for their shitty version control system. Yes, they had fulltime people employed just to resolve VCS conflicts.
After that I worked at Arianespace (X-ray NDT, visualizing/tagging dicom scans, image recognition of faulty propellant tank welds), and after that I switched to biotech, first phytogenetics, then immunology, then pharmacokynetics.
In between I have grown & synthesized and sold large quantities of recreational drugs, taken care of some big felines, got a pilot license, taught IT at an elementary school, renovated a house, and procreated.
A lot of it was to prove myself to the world -- prove that a nearly-broke-orphan-high-school-dropout could succeed at life.
But hey, now I work for a "startup", so I guess I failed after all.23 -
So I told my wife one week ago: "Yeah, you should totally learn to code as well!"
Yesterday a package arrived, containing a really beautiful hardcover book bound in leather, with a gold foil image of a snake debossed into the cover, with the text "In the face of ambiguity -- Refuse the temptation to guess" on it.
Well, OK, that's weird.
My wife snatches it and says: "I had that custom made by a book binder". I flip through it. It contains the Python 3.9 language reference, and the PEP 8 styleguide.
While I usually dislike paper dev books because they become outdated over time, I'm perplexed by this one, because of how much effort and craftsmanship went in to it. I'm even a little jealous.
So, this morning I was putting dishes into the dishwasher, and she says: "Please let me do that". I ask: "Am I doing anything wrong?"
Wife responds: "Well, it's not necessarily wrong, I mean, it works, doesn't it? But your methods aren't very pythonic. Your conventions aren't elegant at all". I don't think I've heard anyone say the word "pythonic" to me in over a decade.
And just now my wife was looking over my shoulder as I was debugging some lower level Rust code filled with network buffers and hex literals, and she says: "Pffffff unbelievable, I thought you were a senior developer. That code is really bad, there are way too many abbreviated things. Readability counts! I bet if you used Python, your code would actually work!"
I think I might have released something really evil upon the world.29 -
https://git.kernel.org/…/ke…/... sure some of you are working on the patches already, if you are then lets connect cause, I am an ardent researcher for the same as of now.
So here it goes:
As soon as kernel page table isolation(KPTI) bug will be out of embargo, Whatsapp and FB will be flooded with over-night kernel "shikhuritee" experts who will share shitty advices non-stop.
1. The bug under embargo is a side channel attack, which exploits the fact that Intel chips come with speculative execution without proper isolation between user pages and kernel pages. Therefore, with careful scheduling and timing attack will reveal some information from kernel pages, while the code is running in user mode.
In easy terms, if you have a VPS, another person with VPS on same physical server may read memory being used by your VPS, which will result in unwanted data leakage. To make the matter worse, a malicious JS from innocent looking webpage might be (might be, because JS does not provide language constructs for such fine grained control; atleast none that I know as of now) able to read kernel pages, and pawn you real hard, real bad.
2. The bug comes from too much reliance on Tomasulo's algorithm for out-of-order instruction scheduling. It is not yet clear whether the bug can be fixed with a microcode update (and if not, Intel has to fix this in silicon itself). As far as I can dig, there is nothing that hints that this bug is fixable in microcode, which makes the matter much worse. Also according to my understanding a microcode update will be too trivial to fix this kind of a hardware bug.
3. A software-only remedy is possible, and that is being implemented by all major OSs (including our lovely Linux) in kernel space. The patch forces Translation Lookaside Buffer to flush if a context switch happens during a syscall (this is what I understand as of now). The benchmarks are suggesting that slowdown will be somewhere between 5%(best case)-30%(worst case).
4. Regarding point 3, syscalls don't matter much. Only thing that matters is how many times syscalls are called. For example, if you are using read() or write() on 8MB buffers, you won't have too much slowdown; but if you are calling same syscalls once per byte, a heavy performance penalty is guaranteed. All processes are which are I/O heavy are going to suffer (hostings and databases are two common examples).
5. The patch can be disabled in Linux by passing argument to kernel during boot; however it is not advised for pretty much obvious reasons.
6. For gamers: this is not going to affect games (because those are not I/O heavy)
Meltdown: "Meltdown" targeted on desktop chips can read kernel memory from L1D cache, Intel is only affected with this variant. Works on only Intel.
Spectre: Spectre is a hardware vulnerability with implementations of branch prediction that affects modern microprocessors with speculative execution, by allowing malicious processes access to the contents of other programs mapped memory. Works on all chips including Intel/ARM/AMD.
For updates refer the kernel tree: https://git.kernel.org/…/ke…/...
For further details and more chit-chats refer: https://lwn.net/SubscriberLink/...
~Cheers~
(Originally written by Adhokshaj Mishra, edited by me. )23 -
In our company the estimation is done by customer / PO. Usually, the deadline is set to the day before yesterday after the issue arrived. Always highest prio.
Oh, almost forgot: when a developer does his estimations, the resulting number gets divided by 7 by the PMs. Buffers? Who needs that. QA? Pfff. We are EFFICIENT.
Deadline not met? Bugs in the release? The developer must be bad.8 -
Just double buffered the Windows console. What you are seeing here is two buffers: one which is empty, and one which has the text "Hello world!", and a pause of 1 second between buffer swapping.
This enables accelerated rendering in the Windows command line (By rendering to an off-screen buffer then simply swapping the active buffer), making things like advanced terminal applications in the Windows console possible.
And the best part- this is the first compilation of the project. Not a single run-time error. What a fucking satisfying accomplishment, honestly.4 -
Just thought I'd share my current project: Taking an old ISA sound card I got off eBay and wiring it up to an Arduino to control its OPL3 synth from a MIDI keyboard. I have it mostly working now.
No intention to play audio samples, so I've not bothered with any of the DMA stuff - just MIDI (MPU-401 UART) and OPL3.
It has involved learning the pinout of the ISA bus connectors, figuring out which ones are actually used for this card, ignoring the standards a little (hello, amplifier chip that is wired up to the +12V line but which still happily works at +5V...)
Most of the wires going to it are for each bit of the 16-bit address and 8-bit data. Using a couple of shift registers for the address, and a universal shift register for the data. Wrote some fairly primitive ISA bus read/write code, but it was really slow. Eventually found out about SPI and re-wrote the code to use that and it became very fast. Had trouble with some timings, fixed those.
The card is an ISA Plug and Play card, meaning before I could use it I had to tell it what resources to use. Linux driver code and some reverse-engineering of the official Windows/DOS drivers got me past this stage.
Wired up IRQ 5 to an Arduino interrupt to deal with incoming MIDI data, with a routine that buffers it. Ran into trouble with the interrupt happening during I/O and needing to do some I/O inside the handler and had to set a flag to decide whether to disable/re-enable interrupts during I/O.
It looks like total chaos, but the various wires going across the breadboard are mainly to make it easier to deal with the 16-bit address and 8-bit data lines. The LEDs were initially used to check what addresses/data were being sent, but now only one of them is connected and indicates when the interrupt handler is executing.
There's still a lot to do after that though - MIDI and OPL3 are two completely different things so I had to write some code to manage the different "channels" of the OPL3 chip. I have it playing multiple notes at the same time but need to make it able to control the various settings over MIDI. Eventually I might add some physical controls to it and get a PCB made.
The fun part is, I only vaguely know what I'm doing with the electronics side of this. I didn't know what a "shift register" was before this project, nor anything about the workings of the ISA bus. I knew a bit about MIDI (both the protocol and generally how the MPU-401 UART works) along with the operation of a sound card from a driver/software perspective, but everything else is pretty new to me.
As a useful little extra, I made some "fake" components that I can build the software against on a PC, to run some tests before uploading it to the Arduino (mostly just prints out the addresses it is going to try and write to).46 -
!rant
Has anyone looked at the linux kernel 1.0?
I am amazed with this! And the comments are priceless
e.g:
tcp.c
/* I hope this returns what I want. */
return(~d+1);
buffer.c
* 14.02.92: changed it to sync dirty buffers a bit: better performance
* when the filesystem starts to get full of dirty blocks (I hope).
*/
So cool!!!!3 -
Agh, holy shit. devRant, I need some love.
I have successfully double-buffered the Windows console (cmd.exe) but all hell breaks loose when you resize the fucking window. The currently active buffer will receive the change in dimensions while the inactive buffer will not, resulting in the window quickly oscillating between the two sizes as the buffers change size.
That got me stuck for about a day. Today, I got it sort of working but it wasn't satisfying at all. I can get it to resize LARGER, but if you resize the window SMALLER, the actual buffer inside the window doesn't change size, so scrollbars appear and I have NO IDEA HOW TO FIX THAT. I somehow need to calculate, or use the API to find, the perfect dimensions (In rows and columns) for the console buffer INSIDE the window buffer for them to not have scrollbars.
And I just - -
I cannot gather the energy to do so right now.
I spent hours finding the solution to this bullshit and ONLY SOLVED HALF MY PROBLEM.
And stack overflow isn't exactly helpful. My problem is so specific that nobody even writes comments on the question.
I guess I need to calculate the amount of characters the screen can hold given the font size and the window size, but fuck, that's a lot of work to do just for something that probably won't even work anyways.
Well, off to the code editor again. Time to inevitably waste my time doing something that won't work.
Yay, programming.27 -
Cross platform terminal library is just about complete!
Here's the same program running in both Windows and "Ubuntu" (WSL, but it's using the ncurses back-end nonetheless)
What my library does:
- Double-buffers the console for drawing (like curses does)
- Translates input into a standard structure (Linux and Windows have different input systems, obviously)
- Does the same thing for output
- Even supports color!2 -
<!DOCTYPE html>
<head>
<title>hiCloudflare</title>
<link rel="stylesheet" src="main.css" />
</head>
<body>
<h1> Don't mind me, just taking my buffers for a walk</h1>
<script type=2 -
You may remember a super long time ago I double-buffered the Windows cmd.exe using c++
tl;dr, here it is in c!
Anyways, I was still learning c++ back then. It wasn't my first project in c++ but it was close and I ran into a lot of issues. The thing worked... but only if you didn't touch it.
Here's the same project (With a lot less bells'n'whistles) written in c. I used a different approach this time, and other than my function naming convention (Which, I honestly don't even know if it's bad or not!), I think this is some pretty solid code!
In the image you see the header file (I used as a summary of the code) and then three x's in a terminal. To do this, the code:
-Creates a ConsoleScreenBuffer handle
-Creates two CHAR_INFO buffers for drawing & displaying
-Draws three x's to the draw buffer
-Copies the draw buffer to the display buffer
-Copies the display buffer to the ConsoleScreenBuffer handle
I'm thinking about cutting out the middle man and removing the display buffer (which holds what is currently displayed) but I think it may actually be useful, and I don't know.
Anyways, I have no friends that understand this stuff so that's why it's here. Cheers.3 -
Code fuckup day or what?! After two weeks where I wasn't on my project and a co-worker handled it, I came back to my project and reviewed what he had done so far.
Me: "I don't understand how this new code part here can work?"
Him: "Uhm, actually, it doesn't, somehow."
Me: "..."
Then he had checked in his stuff with spaces while the whole project is with tabs. And variables that were used in a different way, but still under the old name, now completely misleading. Bypassing existing infrastructure and defines with "just for this case" hacks. But the best was tracking higher level state by peeking into lower level data buffers, even pulling out their data definitions into global header files - instead of using proper states in the higher layer itself.
NOT! IN! MY! FUCKING! PROJECT!!!
So I spent the day cleaning up the shit to fight off software rot right in the beginning.4 -
HTTPS requests in most languages:
Import a couple of libraries, you may need to install a few as well. It's possible that you will need to initialize and set up the socket. Be sure to specify SSL settings. Create the connection, provide it a URL, and attempt the connection. Read the response, usually in chunks. You may need to manually create a buffer of fixed size, depending on if the language has buffer helper classes or not. You will probably need to convert the input stream response to a string to do anything with it. Close the connection and clean up any buffers used.
HTTPS requests in Python:
import urllib
urllib.YEET()6 -
Twenty years.
For twenty years I've used vim almost exclusively, and only now have I learned about buffers and registers. It feels like wasted years, but also it feels like a gift.6 -
Sorry, need to vent.
In my current project I'm using two main libraries [slack client and k8s client], both official. And they both suck!
Okay, okay, their code doesn't really suck [apart from k8s severely violating Liskov's principle!]. The sucky part is not really their fault. It's the commonly used 3rd-party library that's fucked up.
Okhttp3
yeah yeah, here come all the booos. Let them all out.
1. In websockets it hard-caps frame size to 16mb w/o an ability to change it. So.. Forget about unchunked file transfers there... What's even worse - they close the websocket if the frame size exceeds that limit. Yep, instead of failing to send it kills the conn.
2. In websockets they are writing data completely async. Without any control handles.. No clue when the write starts, completes or fails. No callbacks, no promises, no nothing other feedback
3. In http requests they are splitting my request into multiple buffers. This fucks up the slack cluent, as I cannot post messages over 4050 chars in size . Thanks to the okhttp these long texts get split into multiple messages. Which effectively fucks up formatting [bold, italic, codeblocks, links,...], as the formatted blocks get torn apart. [didn't investigate this deeper: it's friday evening and it's kotlin, not java, so I saved myself from the trouble of parsing yet unknown syntax]
yes, okhttp is probably a good library for the most of it. Yes, people like it, but hell, these corner cases and weird design decisions drive me mad!
And it's not like I could swap it with anynother lib.. I don't depend on it -- other libs I need do! -
Watching tutorials in youtube.
- I know what he's gonna type.
- press right arrow to skip 5sec
- youtube buffers the time jump for 7 secs
.. Bad time investment...3 -
Recently, I had to make a minor modification to some Node.js code a coworker wrote a year ago which buffers stringified JSON into Kinesis. I just needed to add a new key to the input object, it took minutes to make the change, but hours to make sense out the absolute trash spaghetti code this guy wrote. After spending half a day trying to make his code readable, I just got so pissed off. I replaced his 15 files/+1,500 lines of uncommented code, filled with classes, factory functions, poorly named functions and vars, and so, so many spelling mistakes.
We now have a single, well commented, 300 line file that does the same thing.
Get that shit code out of here. -
New colleague comes to present himself. Sees me editing using key bindings, multiple buffers showing in Emacs, bash scripts running in separate terminal...
"I have no idea what you do around here, but I'm sure your a pro"
Seems like a smart guy to me.1 -
Worked 6 hours straight without a break today. Completely exhausted😌, but the level of satisfaction out of the world!😊1
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!rant
For all of youse that ever wanted to try out Common Lisp and do not know where to start (but are interested in getting some knowledge of Common Lisp) I recommend two things:
As an introductory tutorial:
https://lisperati.com/casting.html/
And as your dev environment:
https://portacle.github.io/
Notice that the dev environment in question is Emacs, regardless of how you might feel about it as a text editor, i can recommend just going through the portacle help that gives you some basic starting points regarding editing. Learn about splitting buffers, evaluating the code you are typing in order for it to appear in the Common Lisp REPL (this one comes with an environment known as SLIME which is very popular in the Lisp world) as well as saving and editing your files.
Portacle is self contained inside of one single directory, so if you by any chance already have an Emacs environment then do not worry, Portacle will not touch any of that. I will admit that as far as I am concerned, Emacs will probably be the biggest hurdle for most people not used to it.
Can I use VS Code? Yes, yes you can, but I am not familiar with setting up a VSCode dev environment for Emacs, or any other environment hat comes close to the live environment that emacs provides for this?
Why the fuck should I try Common Lisp or any Lisp for that matter? You do not have to, I happen to like it a lot and have built applications at work with a different dialect of Lisp known as Clojure which runs in the JVM, do I recommend it? Yeah I do, I love functional programming, Clojure is pretty pure on that (not haskell level imo though, but I am not using Haskell for anything other than academic purposes) and with clojure you get the entire repertoire of Java libraries at your disposal. Moving to Clojure was cake coming from Common Lisp.
Why Common Lisp then if you used Clojure in prod? Mostly historical reasons, I want to just let people know that ANSI Common Lisp has a lot of good things going for it, I selected Clojure since I already knew what I needed from the JVM, and parallelism and concurrency are baked into Clojure, which was a priority. While I could have done the same thing in Common Lisp, I wanted to turn in a deliverable as quickly as possible rather than building the entire thing by myself which would have taken longer (had one week)
Am I getting something out of learning Common Lisp? Depends on you, I am not bringing about the whole "it opens your mind" deal with Lisp dialects as most other people do inside of the community, although I did experience new perspectives as to what programming and a programming language could do, and had fun doing it, maybe you will as well.
Does Lisp stands for Lots of Irritating Superfluous Parentheses or Los in stupid parentheses? Yes, also for Lost of Insidious Silly Parentheses and Lisp is Perfect, use paredit (comes with Portacle) also, Lisp stands for Lisp Is Perfect. None of that List Processing bs, any other definition will do.
Are there any other books? Yes, the famous online text Practical Common Lisp can be easily read online for free, I would recommend the Lisperati tutorial first to get a feel for it since PCL demands more tedious study. There is also Common Lisp a gentle introduction. If you want to go the Clojure route try Clojure for the brave and true.
What about Scheme and the Structure and Interpretation of Computer Programs? Too academic for my taste, and if in Common Lisp you have to do a lot of things on your own, Scheme is a whole other beast. Simple and beautiful really, but I go for practical in terms of Lisp, thus I prefer Common Lisp.
how did you start with Lisp?
I was stupid and thought I should start with it after a failed attempt at learning C++, then Java, and then Javascript when I started programming years ago. I was overwhelmed, but I continued. Then I moved to other things. But always kept Common Lisp close to heart. I am also heavy into A.I, Lisp has a history there and it is used in a lot of new and sort of unknown projects dealing with Knowledge Reasoning and representation. It is also Alien tech that contains many things that just seem super interesting to me such as treating code as data and data as code (back-quoting, macros etc)
I need some inspiration man......show me something? Sure, look for a game called Kandria in youtube, the creator, Shimera (Nicolas Hafner) is an absolute genius in the world of Lisp and a true inspiration. He coded the game in Common Lisp, he is also the person behind portacle. If that were not enough, he might very well also be Shirakumo, another prominent member of the Common Lisp Community.
Ok, you got me, what is the first thing in common lisp that I should try after I install the portacle environment? go to the repl and evaluate this:
(+ 0.1 0.2)
Watch in awe at what you get.
In the truest and original sense of the phrase (MIT based) "happy hacking!"9 -
Just what the fuck is up with the senior devs in my team? Just because it's my first job as a developer doesn't mean I can't be right at times. Why can't they fucking digest that they could be wrong at times and me trying to tell them what could be improved is just for the product and has nothing to do with their egoistic selves.4
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"It's like social media, except like Facebook: except instead of poking, you can 'nudge' people!"
http://youtu.be/1LZU8oa2RqQ -
I've decided to switch my engine from OpenGL to Vulkan and my god damn brain hurts
Loader -> Instance -> Physical Devices -> Logical Device (Layers | Features | Extensions) | Queue Family (Count | Flags) -> Queues | Command Pools -> Command Buffers
Of course each queue family only supports some commands (graphics, compute, transfer, etc.) and everything is asynchronous so it needs explicit synchronization (both on the cpu and with gpu semaphores) too4 -
This is a question and a rant about my frustrations with an API description. First take a look at this usage information for a library I have been playing with:
https://github.com/avaneev/avir/...
Now my first question: Is it clear as to you what the formats are for the InBuf and OutBuf parameters are?
Now, read his response to people (including me) struggling with determining the format of the buffers for this resize function:
https://github.com/avaneev/avir/...
Does the guy come across as condescending as hell? Am I reading into this? It is like the guy takes every opportunity to find fault with people not understanding the details he didn't put in his API description. I would find it difficult to have to work with someone like this.
The irony about this is the description of his code makes me think it is going to magically create this wonderfully rescaled image preserving details. The result is that a standard bilinear filtering scaling function looks practically the same. I saw no real perceptible improvements of his code over the scaler I tested against. When I adjusted parameters using presets he provided it didn't improve the results and added artifacts I could not accept. His scaler is also at least a magnitude slower than the bilinear version. So the code is pretty much a non-starter for my current project.
Ah well, I appreciate him posting the code and making it a very permissive license. That part is really cool.16 -
I looked at an SQL server today from a customer, talked with one of their devs and he said that he's unable to understand why the server misbehaves... All (!) queries were optimized, but they have 'big data queries'... Migraine started, I had a very bad feeling. Monitoring? Nooooppeeee. Migraine kicks in. Connected to server. SHOW GLOBAL VARIABLES...
After a bit of scrolling I found a lot of misconfigured variables (e.g. extreme large join buffers, unrealistic buffer sizes), high slow query count (nearly 60 % of COM_SELECT) and a few variables that were unknown to me.
Then came the version line.
5.0.46
Yes. 5.0.46.
Big data? Well... 30 GB of usage data.
I called the company back... The dev told me sternly that this was the production server (I had hope...) and that I lie - neither the version, nor the variables could be the problem.
A coworker had to verify it and our manager had to do the communication... Worst, most traumatic working day I ever had. -
Finally finished an algo to check an image for grouping of pixels that will form a rectangular area. I got the grouping to work on one image, but found it was utterly failing on another. I went through every step of the algo and still could not find the solution. The 128x128 image was working, but the 128x16 image was not. I knew it had something to do with the dimensions. Started thinking it was overflowing a buffer somewhere. So I started putting asserts in the functions that abstracted the buffer access. None of the numbers exceeded the proper bounds. It was close to bedtime so I finally gave up. I was tired. Then I realized it wouldn't be until the next evening when I could look at this again. So I got up again and started looking at the code again. I had a loop to check the output of my algo that I did the memory access of the buffer. It too was not fully filling my temp image to show how the algo was working. WTF!
Then I finally realized the flaw:
buffer[x+y*height]
And my test loop to test the algo:
buffer[x+y*ymax]
I kept overlooking the error because I was sure it was right. Also my asserts for the functions to access the buffers? They only checked the inputs x and y. So it didn't help that the math was wrong for reading and writing the buffers. It also worked fine on 128x128 images because the width and height were the same.
It is funny that I struggled with this part. The algo was actually surprisingly easy to formulate. I just looked through every point and checked a buffer to see if that point was used. If not then I would attempt to grow in the x and y direction the shaped of that point based upon pixel color. This was saved in a structure while growing that point. Then when that rectangle could not be grown further the inner loop would continue checking used points again.
I still have work to do to use the data this algo produces. I need to now figure out how to parent the rectangular areas to each other. I will probably use my check buffer to keep track of these rects by an index. Then do adjacent checks to determine parenting. Eventually I will have to extend this algo to 3 dimensions, but that should not be difficult.2 -
I don't want to spend a whole day tracking a crash back through multiple systems just to find a buffer that was initialised with garbage, wasn't written into completely, and as a result just *happened* to contain an exact value that causes a crash later on. If you're doing weird low-level things in C/C++, ZERO-INITIALISE YOUR DAMN BUFFERS.
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I got my circular buffer working for my oscope display I am working on for audio data.
https://github.com/Demolishun/...
I plan on expanding this to have more functions for bulk operations. I also want my fake iterators to be able to be used with <algorithm> functions.
It was pretty awesome last night to finally get to see my audio waveforms displaying properly.1 -
I think the Golang serialization API is utter garbage.
By convention it usually looks like this,
MarshalFormat() ([]byte,error)
UnmarshalFormat([]byte) error
This means that all serialization and deserialization is done on, heap allocated, in memory buffers ( technically also mmaped files, but thats not cross platform).
As the Go GC is ruthlessly optimized for minimum latency, this can potentially cause memory leaks in long running applications.
I think we need a new serialization API that looks more like
SerializeFormat(io.Writer) error
DeserializeFormat(io.Reader) error3 -
So I have somehow created schrödinger's cat in my program. If you observe what is happening, it works. But if you stop observing it, it starts corrupting.
If I put any print statement in it, it works. But if I have no print statements at all, it produces corrupted data. Doesn't matter what or when I'm printing.
I'm guessing its there's some fuckery going on with stdin/stdout and buffers. Even though the data coming to and from stdin/stdout should not affect the output.10 -
I had a pretty good day.
I had my first pay raise as a dev;) not huge but i wasnt expecting one for another 4months ;)
And i was working on a security scrip for after effect plugins. The thing is called Extendscript and is built on top of ecma3. Yeah javascript version from 1999. Hashing stuff gave me different results. Took me about a week to realise that the string buffer were different and i had to parse in latin something to have the same matching buffers. What a hassle man. Let alone trying to make it work with Windows terminal which after starting with Linux then mac, windows seems sooo sucky.
But yeah its my first security scripts so 2 main achievements for me today! Ive waited 4 years to reach a level where i now feel like a real professional dev. ;) sry not a rant ;) -
I don't always forget to turn off caps lock,
but when I do, it's in VIM AND WIPE OUT HALF THE FILE
you know I love you VIM1