OpenEuphoria

1. The NickFrac screensaver, or How I Broke My Brain

• Posted by prickle Aug 04, 2009
• 1234 views

Hi, all. I have just uploaded the full source and a Windows installer of the NickFrac screensaver to the archive. I would put it forward as having the most ridiculously convoluted code base of any program I have written. It is a prime example of how not to write maintainable code.

Not that it is large, just stupefyingly twisted and difficult to follow. For example:

Languages within languages within languages. Three lexicons are used, Euphoria, assembly and one all of it's own, often all within a single statement.

Multiple parallel versions, there is an almost complete development implementation in DOS.

Self-compiling, it has it's own built-in JIT language and parser and both versions can build portions of themselves into precompiled include files.

Self-modifying at multiple levels, not only is the embedded assembly altered during build time but the assembled machine code is altered during runtime on a per-fractal basis.

Complicated math, comprehensive fractal dynamics analysis expressed in the most primitive low-level fashion.

Why did I do it this way? All for execution performance. The images produced require not one fractal plot but many hundreds of complete fractal plots superimposed one on top of another. Any other method would be too slow for a screensaver.

So now I want to return to this code, extending it to a more full-featured fractal explorer. Trying to read the code, let alone understand what I was doing is as difficult as if I had never seen it before and makes my brain hurt. Very little of it makes sense and I expect it is up for a rewrite once I rediscover it's secrets.

Nick

3. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by prickle Aug 04, 2009
• 1223 views

Bugger. I have had this problem before. Spurious mouse move events from nowhere. I have a hack to fix it, but it is less than ideal as the screensaver then requires quite energetic mouse movements before it quits. I will update the code, rebuild the installer and resubmit. Gimme a day or two, I have misplaced the original installer script.

Thanks Andy.

Nick

5. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by AndyDrummond Aug 04, 2009
• 1139 views

I can wait OK! And I don't mind a quite big wiggle on the mouse. In fact I prefer that, really. there are some screen savers I turn off, some I think are OK, and some are better than working! Yours looks like the latter...

Andy

7. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by prickle Aug 04, 2009
• 1160 views

Wow! high praise indeed. Perhaps it was worth a broken brain after all. RDS now has the fix.

Power users may note the interactive features of the screensaver. Pressing space bar will start a new fractal and control-s will (very slowly) capture the current image (watch the red bars crawl down the sides of the screen!) and then allow it to be saved.

Thanks, Andy.

Nick

9. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by AndyDrummond Aug 04, 2009
• 1163 views

A bit more information: it seems that it is possibly disk activity which trips it. I was doing a search for SAVER.EXE and while it was doing that I couldn't preview more than a few millisex. I stopped the search and got back to running for a few seconds before popping back. So ...

Andy

11. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by AndyDrummond Aug 05, 2009
• 1194 views

Nick, I waited for a few hours and downloaded NickFract, and same problem. At home, at midnight UK, I downloaded it to my desktop PC (also XP SP3) and it was fine. I watched it avidly for a while before going (back) to bed! This morning I downloaded it to my laptop, and followed your instructions this time, and Hey Presto! All OK! No work for a while - when I need to think, I have this new aid to thinking there!

It reminds me of the film 2001 (or one of its successors) with the caveman looking at a screen and learning something - I feel if I watched enough I'd learn the art of time travel, design a space warp and probably anti-gravity after coffee. So there is a challenge! I love the idea of programs which self-compile, self modify, and generally think for themselves ... much better than just clicking together Lego modules of code, much more rewarding ... so thank you, Nick, great work.

Andy

13. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by prickle Aug 05, 2009
• 1192 views

Hi Andy. The reason I did it like that is because the program doesn't use any backing store or screen buffer. The output of the engine is drawn straight to the visual and is destroyed if anything moves over the top of it, like another window or progress bar or something. Fractals went faster that way. This is why the screen is "captured" with little red bars rather than the image being instantly available to save.

I do not have a good knowledge of the Windows API, there may be some much better way to do this. What I think it means though is any visual feedback we give the user at the point they press Ctrl-S will damage part of the image. Not wanting that to happen, we need to simply sit and wait for the fractal to finish before capturing it. Wondering what's going on, the user presses the key again. and again, mashing the keyboard in a frenzy of impatience. Suddenly, dozens of save-as windows appear and the computer crashes. Well, maybe not, but I can't think of a good way. Any ideas?

What I did back when I still used Windows was crank the iterations up by a factor of ten or more on the chaotic fractals like the IFSs and the Strange types so they ran much longer to give me a a better chance of capturing one I liked and turned all the boring ones off. I was thinking of updating the defaults, they were set back in '02 when life was slower but I keep forgetting. Each chaotic fractal type was intended to linger for up to a minute. On a modern machine they probably skip by a bit too quick.

Hmm. not sure. Perhaps if I captured every fractal when it was finished and kept the last ten in a directory somewhere?

Here's to not working,

Nick

15. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by prickle Aug 09, 2009
• 1273 views

Hi, Andy.

Yes, that would work. How about ctrl-S saves the current image as per the current behaviour, and ctrl-L saves last image, if it exists?

Yes, it was hard work given the get_pixel->Euphoria sequence algorithm I was using. I have now discarded this most shameful algorithm and have implemented the Windows Recommended Method of obtaining a DIB and peeking it straight out to a file. This is orders of magnitude faster.

Andy, I am thrilled you are taking an interest in this. I pretty much wrote it for my own interests and desires which I satisfied back in '02. Since then I have passed it around and received very little feedback other than for when things broke. Constructive criticism, comments and suggestions are not only welcome but actively sought. Thanks so much.

I never anticipated the images would be printed. Glass on black was my own personal preference. Perhaps it is worth including a method to select a background colour.

Yes, a thumbnail display would be nice, but perhaps unnecessary if we find a better way. It would look stylish tho. BTW this is not work for me, it is a hobby (or as some would call it an unhealthy obsession) and generates much pleasure. I simply have exhausted my ideas for this work and need fresh perspective. I am well prepared to take this little screensaver to the next level if people let me know what they like.

Would you or anybody listening be willing to test my intermediate code? I do not have Windows and am testing my new code using WINE. Unfortunately, not everything works in the WINE environment, namely toplevel windows, such that the screensaver proper does not run. The settings dialog is fine though and is enough to develop with. Nevertheless, it would be good for operation to be verified in real Windows. I don't want to bother RDS with incremental updates so please fetch the new ready-to-go .SCR here. Copy this into your Windows directory as per previous updates.

What's new: The ctrl-S save image function should now be virtually instantaneous. Otherwise, the program is functionally the same. This is the first step to extending functionality.

Something I now realise you may not be aware of and I probably should have mentioned is the other interactive mode. When you are in the settings dialog, you can click on the small preview window to detach it from the gui and manipulate it like a normal window. It works the same as the screensaver proper with the interactive keys allowing save and skip, but it will only generate fractals of the type currently selected in the settings dialog and will stop when the fractal is done generating. This is probably the best way to currently save a completed fractal, but it will only be at the resolution of the fractal window. It would appear this functionality is quite non-intuitive. Turns out nobody expects to be able to click on a preview. Perhaps this should also be changed.

Cheers,

Nick

17. Re: The NickFrac screensaver, or How I Broke My Brain

• Posted by prickle Aug 10, 2009
• 1186 views

Fabulous. All working then. As far as the icon is concerned, anybody is free to do whatever they please with the generated images. There are no issues with copyright or ownership, I consider any image one generates as your own artwork. If in fact somebody does like a fractal enough to make a logo with it, I'd be chuffed.

LOL agreed networking is the current fashion. Mind you fractals were pretty popular probably 10 years back when scientists were trying to use them to explain life and stuff. Personally, I see fractals as a kind of something for nothing, pretty pictures from a handful of almost random numbers. Oh, and I'm an AVR man myself. Another of my technical hobbies.

Sure thing. Thanks again for your lunchtimes.

No problem. I will post you some info and we should probably start collaborating directly to save the forum from all those gory details. We have much to discuss.

Cheers,

Nick.