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Dirty Coding Tricks To Make a Deadline
Gamasutra is running an article with a collection of anecdotes from game developers who had to employ some quick and dirty fixes to get their products to ship on time. Here's a brief excerpt:
"Back at [company X] — I think it was near the end of [the project] — we had an object in one of the levels that needed to be hidden. We didn't want to re-export the level and we did not use checksum names. So right smack in the middle of the engine code we had something like the following. The game shipped with this in: if( level == 10 && object == 56 ) {HideObject();} Maybe a year later, an artist using our engine came to us very frustrated about why an object in their level was not showing up after exporting to what resolved to level 10. I wonder why?"
Have you ever needed to insert terrible code to make something work at the last minute?
If you have short deadlines, you end up with issues similar to the bugs Ubuntu needs to smooth out every release. If you go with "It'll be finished when it is finished", Your stable releases can become ridiculously out of date between versions. Debian did a good thing by abandoning the open-ended release cycle in favor of the extremely long but predictable two-year deadlines.
The deadline is looming, I can't spend much more time on this. So, I did the unthinkable -- I packed the controller id into the pointer parameter. I marked it as a horrible hack in a 4-line all-caps comment, and checked it in.
Does not sound so horrible, just make sure the 1,2,3,4 pointers never point at anything "free()"able and it'll work fine.
BTW, is that Wolf 360 game out?
A 3d model export would break regularly screwing up the texture map orientation on certain polygons. The godawful export couldn't be fixed on the deadline, and risk management said best not to touch it cuz EVERYTHING might bust, let alone all the coders being nailed to the wall by the ship date. So I fixed the model files in an ascii editor. All the art builds that had tweaks needed this "touch" Since it was a hockey game, you can imagine how many goalie pads that was. Oh yeah, you couldn't see if the fixes were correct except in the game engine after more pipeline.
Technically not a code fix, but still a valid solution.
I once worked at a Fortune 25 company in Chicago. They had this ENORMOUS mainframe program written in COBOL that ran their order inventory system which accounted for 20% of the companies revenue. All the guys who wrote this grunting pig of a system had either retired or had passed away. In the middle of the code was the following;
*
* We don't know what this does.
* Please leave it alone !
*
SET INSIDE-INDEX TO 1.
*
* We don't know what this does.
* Please leave it alone !
*
If this statement was commented out or removed the system stopped working. No one could find the problem. People had spent years looking for it but the code was such a mess and the documentation was so useless that they just left it alone and made a note that when the order inventory was re-done to make sure they left this "feature" out. I have been told that many old system have similar problems.
Another day closer to redwood heaven
Way back we had a project where we had to simulate entire train traffic entering Helsinki train terminal. Someone else had made the simulator and it ran pretty neatly, but unfortunately crashed mysteriously after about four - six hours of simulation time. Our customers were coming the on monday and I spent my sunday trying to figure out how this simulation worked and what crashed it. Finally I caught the problem, which was as simple as some null pointer to a train schedule or something similar which needed to be referenced. I couldn't figure out why it was null in time, so I just added test for null pointer, which skipped said code. Program ran fine and we got our money. Never figured out what was wrong with it. Luckily it was only a simulation.
Example? Right here:
#include <stdio.h>
void *f(void)
{
a:
printf("Here!\n");
return &&a;
}
int main(int ac, char **av)
{
goto *f();
printf("There\n");
return 0;
}
You often cannot develop software with the language you want, but must develop it with the language you have. C has no such features and, therefore, goto is used more often than in languages that have them. Fit the strategy to the tool.
This is reasonable, but it assumes some other function can do the needed cleanup code or other data massaging just as cleanly. If the goto is being used because finding the value is an error condition, you often have to do certain things as soon as possible in the code so you do not lose important debugging information.
And, no, exceptions are not part of C, and setjmp/longjmp is, if anything, even less likely to pass code review. An advantage of goto is that you can keep the cleanup code in the same function, visually close to the rest of the logic and sharing the same locals.
How can you use my intestines as a gift? -Actual Hong Kong subtitle.
Some of the worst I have seen:
In critical C code:
if (some condition)
i *= 0;
else
i *= 1;
And I was the actual variable name.
Even worse, on a different project, an Easter egg that told the user their hard drive was about to be erased, and another that popped up about 30 dialog boxes full of banter between Spock and Kirk. Worst of all this code written in VB and was licensed for megabux then we got hold of it for orders of magnitude more megabux (Most of the original coders were hired fresh out of highschool). It ended up being rewritten (thankfully NOT by me) but we had to get the source to work out how it worked in the first place.
I wish I was making this up.
These posts express my own personal views, not those of my employer
That's completely understandable in this case of programming in Prolog.
Prolog is a declarative language.
You declare the rules, and the system figures out a result that matches those rules.
The problem is that this basically doesn't work. So a Prolog programmer has to write the "declarative" rules in a procedural order so that the run-time system doesn't have to try every possible combination to find (or fail to find) a matching result.
The proper ordering of declarations can be quite subtle. With a modestly complex program you can make a seemingly unimportant change in the order of the declarations and have the runtime go from a second to a week.
In this case the professor didn't (couldn't) know how long a Prolog program to solve this problem should take. He just assumed that you had found a more efficient ordering for the declarations. He might even have thought it was luck rather than deep insight that your program was faster than his. But you have to a decent understanding of the limits of Prolog to get a complex program to complete in a reasonable time, so you had to be good before you could get that lucky.
If you couldn't already tell, I have a low opinion of Prolog and declarative languages. They are "parlor tricks". Much like computer 'Life' and neural networks, simple programs can produce unexpected seemingly-sophisticated results. But they don't get better from those initial results. To compute the answers or results you want in a reasonable time, you end up with at least the complexity of writing things in the traditional explicitly procedural method.
The promoters of declarative language typically don't mention that you end up writing rules in an explicitly procedural order if you want the program to work. If you press them on the issue, they then say "well, OK, it's not actually any easier to write, but it's easier to verify that you've correctly specified the desired result." But if you have to carefully shuffle declarations around, and even then some results unpredictably take centuries to compute, pretty much no one cares.
But as below says, they make error handling an easier task as well as some oddly structured loops for which try/catch logic doesn't get you all the way
Ugh. Magic invisible gotos FTW!
I like the way my former VB teacher put it (and yes I use the occasional GOTO, but then again I learned in the real BASIC-Commodore BASIC) he said "The GOTO is like a chainsaw. yes, some folks can actually make good things, and even make really nice carvings with a chainsaw. most just make a big fucking mess."
Of course me and him both laughed our asses off when some 19 year old tried to rip off my code and pass it off as his own. After laughing and giving the kid a big F the kid said "How do you know that he didn't steal it from me?". So he asked the kid where he learned VB and which OS and the kid said "Windows 98 and the VB I got from this class!" and the teacher projected the code onto the board and said "Now class, does anybody notice something a little...weird about this code?" and a girl popped up and said "Why are their numbers before the lines, and what is a GOTO?".
The teach just laughed and said "once upon a time their weren't any GUIs on personal computers. All you got when you turned it on was a blinking CLI and you had to write your own programs, using VERY old syntax. The person who wrote this is used to working in teeny tiny amounts of memory and using the old style, which works just fine if you know what you are doing, but if not it'll blow in your face like Mr. Greene found out when he tried to snatch this code and incorporate it into his own without knowing how it works" he then turned to me after staring at the code for a minute and said "Atari or Commodore?" and I looked shocked and said "Commodore VIC20, but how did you know that?" and he said "because I have been around long enough to have coded on just about everything, and that looked liked Atari or Commodore code. Very efficient, but about as subtle as a chainsaw." which is when he gave me the chainsaw quote.
So I have never forgotten the chainsaw quote, and while I can wield the chainsaw without making a mess, I saw first hand when others in the class tried to use GOTO what a mess you can make if you don't know EXACTLY what your code is doing. He caught me outside a month later and said "thanks a lot, I hadn't seen a GOTO in ages and then you come along and it spreads like the damned clap. Giving these youngsters GOTO is like handing a monkey a sledgehammer and letting them loose in a bomb factory. There is no doubt they are going to go boom, the only question is when." but what can I say, I'm just an old greybeard that was used to numbered lines and GOTO.
ACs don't waste your time replying, your posts are never seen by me.
You laugh, but that's the basis of 'Test Driven Design'. :D You were only supplied with 1 test, and you passed it. Had their been more tests, your code would have had to be what was really wanted.
I've started to think about how a class could be run like that... Create a series of unit test sets that progressively test more of the program. For each assignment, give the students the next set of tests and have them code to make the tests pass. In the next class session, work to show everyone how to make it happen, then give the next set.
"If you make people think they're thinking, they'll love you; But if you really make them think, they'll hate you." - DM
So it was 1999 and I was working for a mom and pop software shop, we had been acquired by a dot com. All our money and toilet paper stock options were held until we delivered the re-branded product with source. Part of the "rules" said we had to have only C/C++ and VB6 source, NO OTHER LANGUAGE.
....(you get the idea)
. We finished converting a few rogue scripting modules and things like that, which creep in over time. But we COULD NOT find the source code to one of our VB6 DLLs (an old one that had not been changed since it was first compiled in VB6). We searched and searched and eventually the fastest coder(not me) started rewriting it. We were 1 day from delivery date and there was no way he could finish it, so I ran it through a disassembler.
the C++ code we delivered looked like this:
int functionName(int parm) {
_asm {
push esi
mov esi, dword ptr ds:[esp+8]
mov dword ptr ds:[edi], esi
retn
}
It was unreadable, but it compiled and worked and we got our money. I still wonder what they ever did with that... since the software is still in use...
We had an easter egg in our code that was in a routine scheduled to be executed only at 0-dark-30 when our users were long gone. But someone later called the routine as part of the loading process, and the users ended up seeing it anyway as they signed on at start of day. It made people smile, so we left it in.
A few years later, we were telling a client that we couldn't add their new feature X because we don't have the memory. At that point the director said to get rid of the easter egg and then it'd fit. (A few hundred bytes was not going to make a difference, but our director didn't care, it was a perception thing.) What we got instead was a hundred bug reports that the easter egg wasn't displaying, and that they "needed" to see it so they'd know when start of day was complete.
John
My Physics teacher caught me doing that once. He pointed out that the intended learning outcome of the experiment was to understand the relation between the properties being graphed, and if I already understood this well enough to work out what the results should be then I had achieved the objective. One of the few teachers I've had who really understood what education was meant to be about.
I am TheRaven on Soylent News
This is the code for the Apollo 11 lunar lander flight computer.
http://code.google.com/p/virtualagc/source/browse/trunk/Luminary099/LUNAR_LANDING_GUIDANCE_EQUATIONS.s?r=258
and yes some of my code is in there along with the equivalent of a few "goto's
Lots of bright people worked on this and in some circumstances a "goto" is required.
*--- Sometimes a majority only means that all the fools are on the same side. ---*
In Real Life dating agencies, there are often a lack of males. So one person who owned it often dated the women, just to keep them on longer and to get more money from them. They were not in the dating game, they were in the 'get money from desperate souls' game.
The reason (his words) was that women were less afraid to admitting to each other that they were unable to find a partner, where male ego's would never admit such a thing.
Obviously with the anonymity that is The Internet, this difference is gone and any man now gets ripped of as well.
Don't fight for your country, if your country does not fight for you.