4 ms·

I wish I still had one of the earliest programs I wrote. It would have been 1996, I was 16, and I had a linear algebra book which had an appendix entry on compu

I wish I still had one of the earliest programs I wrote. It would have been 1996, I was 16, and I had a linear algebra book which had an appendix entry on computer graphics. I had taken a programming class the prior quarter. I got hooked writing a program to draw rotating wireframes of a few different shapes. I almost failed the class because I was so distracted by this. I didn't know about arrays yet. Every vertex was its own variable with a hardcoded default. Every entry in the rotation matrices was its own variable. The code to do matrix multiplication therefore didn't have loops, just a long list of calculations. Which had to be duplicated and adapted to every vertex. I did know about pointers, I had to draw to the screen after all, which was done by writing to memory starting at a known address. So at least I had loops rasterizing the lines between vertices. Which means I definitely had the concept of arrays and indexing into them, I just didn't know enough to make my own.

sbarre 3y ago
Do you recall which shapes you created?
- furyofantares 3y ago
  I remember there were 3, and that there was a cube and a pyramid. I can't recall the third. Maybe I did both a square pyramid and a triangular pyramid.
phkahler 3y ago
Same. When I was 12ish trying to write a Pac-Man game in basic, I dreaded writing the logic for the 4 ghosts. I'd need separate code for the ghosts at (x1,y1)....(x4,y4) and said to my dad it would be cool if I could use xn and yn inside a for loop, but those are just 2 more variables. I wanted n to indicate which one. This seemed kind of weird, but it's what I really really wanted. He grabbed the little basic book and showed me that x(n) was actually a thing! I think back to this in discussions about teaching. Abstract concepts are best understood when the student has a legitimate need for them. You can explain something all day and have their eyes glaze over wondering why something is important, but if it solves a problem they have it will click in seconds or minutes.
- quirino 3y ago
  When I started programming at 12-13 I had no idea loops or arrays existed and implemented an absolutely criminal Tic-Tac-Toe game. The same year me and a friend were studying for the national Informatics Olympiad and we were completely stumped when faced with a problem that required a list: "How do we know how many variables to declare if we don't know the N beforehand?". (The problem if anyone is interested: https://neps.academy/br/exercise/384 https://neps.academy/br/exercise/384. Given a list of up to 50k distinct numbers (with values up to 100k) and another list of 50k numbers that should be removed, print the resulting list. Time Limit: 1 second.)
  - freetime2 3y ago
    When I first started coding, I thought loop structures were confusing and redundant when I could accomplish the same thing with GOTO. So that’s how I implemented all my loops for years until I eventually took a course and a teacher told me I was never to use GOTO again.
    - deleted 3y ago
      [deleted]
    - wongarsu 3y ago
      Dijaksta's “goto considered harmful“ is often interpreted as a much broader opinion than it was, but this is a perfect example of what he was against
      - User23 3y ago
        Yeah Dijkstra's main objection to goto is that it's really hard to formally define its semantics and even if you do, the formalism is so complex it's hard to reason about. Break and continue on the other hand are considerably easier to formalize.
  - matheusmoreira 3y ago
    > national Informatics Olympiad That brought back a lot of memories... I wonder if there are participation records. The olympiad website isn't responding. I also took part in the astronomy olympiad.
Y_Y 3y ago
The obvious solution here is to use the lower part of the screen as working memory while drawing the upper part. By the time you get to the bottom you shouldn't have many calculations left anyway. This has the benefit of using fast gpu ram and is therefore cuda and very ai.
- adastra22 3y ago
  If only GPUs existed back then. This would have been very slow memory mapped video ram.
almostnormal 3y ago
The first part of GWBasic I learned by asking someone for help was "chain", after having taught myself print, input, if, and goto from the documentation.
canjobear 3y ago
I did something similar for my big middle school hit, a TI-83 version of Snake. Every x and y position of every segment of the snake went into a separate variable. The snake could only get so long because TI-83 BASIC only gives you so many variables.
- xp84 3y ago
  IIRC I think it only gave you a fixed number of arrays, too, though I think they could get pretty long so you could probably have done that. Also it’s rad that you were programming the TI-83 in middle school. I learned TI BASIC in high school for both fun and academics. (I created programs to solve each kind of trig problem we were assigned complete with shown work, with the full blessing of the teacher who could see that understanding was obviously a prerequisite to being able to code a solver.)
ljm 3y ago
It reminds me of one of my earliest ventures into freelancing, where all I had was a tiny VPS that supported PHP. I had to process a large spreadsheet which had maybe 5/10k entries in it. Small potatoes these days, compared to that time in 2002/2003. I wasn't a computer scientist so I read the file in the dumbest way possible, but kept getting errors about memory usage and running out of space since I was looping within loops within loops. I went through it and added `$variable = null` at every opportunity. Lo and behold it worked.
- dotancohen 3y ago
  Holy feces I think that I inherited your parser. Was it for a US client, in the field of cash advance loans?
  - ljm 3y ago
    No, not even close :)
    - dotancohen 3y ago
      Well, then, you can rest knowing that other parser writers came to the same workaround as you did!
_the_inflator 3y ago
Welcome to the world of optimization the hacky way on an old computer, where code is data is code, and the only truth is: does it render in as many frames as possible? ;) Usually, you cannot achieve this by engaging in academic code with recursion and loops; you have to do the opposite: trade readability and compact code for speed. Sometimes, code for 6510/68000 is so optimized - usually unrolled - that you get code patterns that resemble data applied at different frames, much like your code. There is nothing wrong from my point of view. ;) (Some words of wisdom: May the debug gods be with you on this journey, though.)

sbarre 3y ago

Do you recall which shapes you created?

furyofantares 3y ago
I remember there were 3, and that there was a cube and a pyramid. I can't recall the third. Maybe I did both a square pyramid and a triangular pyramid.

phkahler 3y ago

Same. When I was 12ish trying to write a Pac-Man game in basic, I dreaded writing the logic for the 4 ghosts. I'd need separate code for the ghosts at (x1,y1)....(x4,y4) and said to my dad it would be cool if I could use xn and yn inside a for loop, but those are just 2 more variables. I wanted n to indicate which one. This seemed kind of weird, but it's what I really really wanted. He grabbed the little basic book and showed me that x(n) was actually a thing! I think back to this in discussions about teaching. Abstract concepts are best understood when the student has a legitimate need for them. You can explain something all day and have their eyes glaze over wondering why something is important, but if it solves a problem they have it will click in seconds or minutes.

quirino 3y ago
When I started programming at 12-13 I had no idea loops or arrays existed and implemented an absolutely criminal Tic-Tac-Toe game. The same year me and a friend were studying for the national Informatics Olympiad and we were completely stumped when faced with a problem that required a list: "How do we know how many variables to declare if we don't know the N beforehand?". (The problem if anyone is interested: https://neps.academy/br/exercise/384 https://neps.academy/br/exercise/384. Given a list of up to 50k distinct numbers (with values up to 100k) and another list of 50k numbers that should be removed, print the resulting list. Time Limit: 1 second.)
- freetime2 3y ago
  When I first started coding, I thought loop structures were confusing and redundant when I could accomplish the same thing with GOTO. So that’s how I implemented all my loops for years until I eventually took a course and a teacher told me I was never to use GOTO again.
  - deleted 3y ago
    [deleted]
  - wongarsu 3y ago
    Dijaksta's “goto considered harmful“ is often interpreted as a much broader opinion than it was, but this is a perfect example of what he was against
    - User23 3y ago
      Yeah Dijkstra's main objection to goto is that it's really hard to formally define its semantics and even if you do, the formalism is so complex it's hard to reason about. Break and continue on the other hand are considerably easier to formalize.
- matheusmoreira 3y ago
  > national Informatics Olympiad That brought back a lot of memories... I wonder if there are participation records. The olympiad website isn't responding. I also took part in the astronomy olympiad.

Y_Y 3y ago

The obvious solution here is to use the lower part of the screen as working memory while drawing the upper part. By the time you get to the bottom you shouldn't have many calculations left anyway. This has the benefit of using fast gpu ram and is therefore cuda and very ai.

adastra22 3y ago
If only GPUs existed back then. This would have been very slow memory mapped video ram.

almostnormal 3y ago

The first part of GWBasic I learned by asking someone for help was "chain", after having taught myself print, input, if, and goto from the documentation.

canjobear 3y ago

I did something similar for my big middle school hit, a TI-83 version of Snake. Every x and y position of every segment of the snake went into a separate variable. The snake could only get so long because TI-83 BASIC only gives you so many variables.

xp84 3y ago
IIRC I think it only gave you a fixed number of arrays, too, though I think they could get pretty long so you could probably have done that. Also it’s rad that you were programming the TI-83 in middle school. I learned TI BASIC in high school for both fun and academics. (I created programs to solve each kind of trig problem we were assigned complete with shown work, with the full blessing of the teacher who could see that understanding was obviously a prerequisite to being able to code a solver.)

ljm 3y ago

It reminds me of one of my earliest ventures into freelancing, where all I had was a tiny VPS that supported PHP. I had to process a large spreadsheet which had maybe 5/10k entries in it. Small potatoes these days, compared to that time in 2002/2003. I wasn't a computer scientist so I read the file in the dumbest way possible, but kept getting errors about memory usage and running out of space since I was looping within loops within loops. I went through it and added `$variable = null` at every opportunity. Lo and behold it worked.

dotancohen 3y ago
Holy feces I think that I inherited your parser. Was it for a US client, in the field of cash advance loans?
- ljm 3y ago
  No, not even close :)
  - dotancohen 3y ago
    Well, then, you can rest knowing that other parser writers came to the same workaround as you did!

_the_inflator 3y ago

Welcome to the world of optimization the hacky way on an old computer, where code is data is code, and the only truth is: does it render in as many frames as possible? ;) Usually, you cannot achieve this by engaging in academic code with recursion and loops; you have to do the opposite: trade readability and compact code for speed. Sometimes, code for 6510/68000 is so optimized - usually unrolled - that you get code patterns that resemble data applied at different frames, much like your code. There is nothing wrong from my point of view. ;) (Some words of wisdom: May the debug gods be with you on this journey, though.)