Bugs
 

While the program is great, I thought I might point out a few bugs:

The starfish has some issues when climbing up the "glass". It is best described by a picture.

There is no method to cycle the random fish. Pressing the spacebar twice does not work.

If you put it in fullscreen mode from the application, white lines flash at the top of the display. Quite annoying. It does not happen in the screen saver.

There is one other major bug, please contact me at johncmckee1@attbi.com

If it helps at all, the program is running on a stock 800mhz PowerBook G4.

Re: the Starfish, just don't look at the wireframe mode while it's climbing up. :)

I don't see the picture of understand what wireframe would have to to with the bug, but I see it too... an not in wireframe.

The starfish is blocked out by it's own shadow on the glass. You can see the tips of it's arms peeking around the shadow, but otherwize it's invisible if it's on the glass. The shadow is pretty much transparent to everything but the starfish which it hides completely... very bizarre. Luckily it's almost impossible to get the starfish up there, especially in screensaver mode, but I'd like to keep him up in the glass all the time AND be able to see him!

mrtew@comcast.net

Yep, you are right...the starfish is blocked by it's own shadow and is invisible...oh well, Version 1.0 will "hopefully" fix that!

:)

One other "bug" (not sure if it's caused by Aquarium, but I don't see what else it could be)....if I have Energy Saver set to power down my monitor after the Aquarium screensaver has been running, my system exhibits unstable behavior. Twice I've had kernal panics after waking the monitor and resuming system activity, and once the system froze and the monitor never woke up. Again I never saw this happening until I installed the screensaver, so it has to be related some how. Is the Aquarium not playing well with other user's Energy Saver settings, or is it just me?

It seems to lose A LOT of frame rate when full screen, is this normal??

Yup, unfortunately it is.

/Tiny

My framerates are usually higher when full screen. Especially higher than when the window is not front one, when MA is behind another window the rates really drop.

Looking at the bigger picture though... isn't anything over 30 really just wasted energy though. I mean how many fps can a LCD display anyway? And how many fps can the human eye even see? Aren't movies shot at 24fps?

I'd have to research, but I don't think LCDs refresh, per se, as the cystals are always excited. Someone with more knowledge will have to help me here.

As for movies, yes they're shot at 24. I am shocked at how often this fact is used to try to prove that you "only need 24". 24 is actually just about the bare minimum. IMAX movies are shot at 48 frames per second at great expense! I don't think they'd do it if you couldn't tell the difference. :)

The human eye can easily see the difference in framerate between 24 and 30 and some people can see the difference between 60 and 80. I'd say 75-80 is the limit of human perception.

I know when I have my monitor refresh set to 60 Hz, I get a headache.

In the application, when comparing a window which nearly covers the window to full screen, sometimes fullscreen is faster, sometimes it is slower.

I have yet to see an instance where the screen saver is as fast as the application. The screen saver has much less control over its environment than the application does, so we don't get as large a percentage of cycles.

Would the people with the starfish on the glass problem please send a picture and a detailed system description (see www.order-n-dev.com)? I've not seen it and I'd like to get it solved pretty quickly.

Thanks!

When I set MA to be the screensaver, it is running at a frame rate of 1.44. However when running the application, it can do 48+ at full screen on my TiG4 500. Is that normal?

For the _moment_ that is normal. Your video card doesn't have enough memory to handle the screen saver in hardware so you are getting the software renderer, which is painfully slow. We are looking into ways to get around the problem right now.

Switching to thousands of colors will give you much better performance in both the app and the screen saver.

The extra width of the TiBook monitor pushes the 8 meg card over the edge, but we are working on it.


Jim

Sorry, I was going to post a picture, but I forgot. Here it is: http://homepage.mac.com/johnmckee/fish.gif

I have a picture of the starfish problem now. Thanks to you for helping me out!

On refresh rate, and I’m only posting this because Feldon asked:

When speaking of refresh rate, there is a LOT more to consider than the “retrace rate. We have to first separate Refresh from Frame Rate. Also, this is VERY brief, but will give you the idea. Here are some fun facts, and then we will put them together.

Most Disney movies are animated on twos, which means 12 frames per second.
Anime is 8 fps.
NTSC is 29.97, double field.
RGB monitors are in the 75 to 160 herz (cycles).

Ok, what does all this mean? Let’s start with Disney. Disney uses 12 because this is the very least “change per second” or frame rate acceptable to them. It is also exactly half of the rate of film, which is 24 fps. Why was 24 chosen? Long story. But basically, it looks good enough vs. cost of film.

Video uses something close to 30 fps, and when movies which are 24 fps are shown on DVD or Video, they hold 6 of those frames a little longer. This is not noticeable to most people (although it still bothers me).

The big issue for both computers and monitors (like TVs) is the decay rate of the phosphors. In the case of TV, what they learned was that by the time the image was done rendering from the top to the bottom, the top was going dark. Thus, each new image made it look like it was flickering. To combat this, they doubled the trace time to about 60 (fields per second, not frames). So each image is rendered twice, but at half the resolution. This makes it look better. In Europe, they use\ the same bandwidth, but instead do 50 fps, and have higher resolution. So stuff looks better, but flickers more.

A comparison can be made of Anime, the Japanese prefer better looking images, and are willing to accept fewer of them (only 8 per second). Keep in mind, when it comes to cartoons, the “bandwidth” is number of lines drawn by a human per day.

Now to LCDs. They have a very long persistence (decay rate). So you basically can stick an image on them, and even if you stop rendering the image, it still looks bright. The down side is that images often smear, and fast colour changes suck.

As to what humans can see, this is a complex question. But 70 fps does seem to be the high end before no notable difference can be perceived.

Movie projectors and expensive progressive DVD players "triple-click" 24 frame per second material, displaying each frame 3 times to result in a solid 72 Hz picture.

Just saw the pic of the starfish. Yes, the critter is blocked by it's own shadow. Evidently, the Mac version is using double-sided polygons. I only use single-sided polys in the original version. That way, when the underside of the shadow is seen, it's invisible and takes zero clock cycles.

WOW! Maybe that means that the Mac version can be sped up (or use less CPU) by switching it over to single sided! At work we use single sided to make renderings go twice as fast. I think this could be good news!

Yes, it's possible that switching to single-sided might speed things up, assuming that double-sided are currently being used. I'll let JimO'Connor speak on that. From the brief time I was able to see the Mac version, it looked like CalcNormals might also be always-on. This can cause a real slowdown on Pentium-based machines, but I don't know about Macs.

Remember that this Mac version is an early Beta, and O'Connor's team has done an amazing job getting it as bug-free as it is. I'm sure that they will continue to find ways of increasing the frame-rate in the coming weeks.