Ultrastudio.org is a the manually curated museum of educational Java applets.
We say museum, as we are fully aware that after long decline Java applet technology is now as useful for sharing your expertise as steam locomotives for the railway. Same as for steam locomotives, museum still makes sense. Not only we can still present the explaining articles and screen shots - the source code of these applets remains available in our site as well. We think, this still makes the project interesting enough to look around.
Most of these visualizations were written on the dawn of Java programming language, when applet was as natural component of the complex page as some complex graphical figure, with nobody even thinking that applets may be problematic or dangerous. Both young and even some older scientists used them to express they ideas and conceptions. Hence frequently these applets were written by people highly competent in the subject being illustrated (biology, physics, higher mathematics) rather than in programming. Where the licensing permits (as a rule, must be open source), we collected, reviewed and fixed such applets from the whole web, as well as offering a collection of our own applets. Below, you will find the overview of that we have already done. While a few applets only required to be found, for many others a programming effort was often necessary to get them running inside a modern browser. Some active contributions were received as well, while not as many as we initially expected. We also have written short introductory articles on the subject. Serious scientific visualizations are often complex enough to make difficult to understand, what is being demonstrated.
All applets were received in the source code, all source code is (still) public and all it have been reviewed by our team, checking against the malware. To tell the truth, no malware of any kind has ever been observed inside our applet collection. Malicious applets are probably written by very different community. These do not come with the complete source code under GPL! When the applets were still running, they were always loaded from binaries, compiled automatically on the server side, ensure strict match between binaries and the public source code version. Unfortunately since the release of Java 7 update 51 you will not be able to launch any applet from this site anyway, unless you configure really complicated browser setup.
While the project used to be public wiki in the past, since October 2015 we have switched into read only mode, to keep the maintenance costs low enough for supporting of the further availability of this museum over many years.
Below follows the brief summary of our collection:
Contents of this page:
We present several topics on electrophysiology that were written by professionals and once released under GPL. Visualizations on morphogenesis and plant orientation were also written to supplement scientific papers in the past. The flock visualizer reliably shows that a group of individuals may have very coordinated activity without having any leader. Biomorphs illustrate some hypothesis on how the evolution may happen.
Due recent contribution we also have a good introductory series about complex plane and also Besicovitch set and Penrose map from the same source. The interactive demonstration of image processing (2D FFT) is available. On SourceForge we found a nice WMC framework to create visualizations of the simple curves with very little programming, but due us being busy with other parts of the project only parabola and logistic growth have been implemented. Generalized Lambda distribution is our first "extinct" applet that ceased to exist anywhere apart our site. The first applet of our project, Mandelbrot set (kind of something "must to have"), was also a mathematical applet.
Mathematical section also contains a "mystery visualization" of the fundamental domain - the only applet for that we were not able to write any article as did not manage to understand that it is showing. Maybe you could help?
Analog electronics include quite important Poles and Zeros topic about analog filtering of the signal, and how to compute such filters with desired parameters. The collection also contains a single cascade transistor amplifier circuit that allows user to alter many parameters and shows the simulated currents and voltages. Depending on how resistors are set, it can demonstrate the work of both grounded collector and grounded emitter.
In Conway's Game of Life series a single applet shows evolution of various colonies, depending on parameters. The user can pause, step and add or remove cells at any step of evolution. Rubik's cube is a working example of 3D visualization even without any graphic acceleration and could also be configured to show up differently. There is a very comprehensive applet on Sudoku, while seems not very popular for some reason. Dissociated press is just a part of the whole hacker culture. There are also two variations of Tic tac toe.
Ray diagram that we initially took from SourceForge but extended in a number of ways seems the most popular applet in all project. From optics, we also have our own Prism. Also Wikipedia uses a screen shot of our Atomic orbitals visualization that we have contributed there. This group also contains pendulum, the only finished visualization of Labs4Wikiversity, the first active project to use applets systematically in encyclopedic material. We have found unusually well prepared open source visualization and explanation of two dimensional collision. Rutherford scattering, while easy enough to understand, can be very nicely illustrated with the applet. Differently, wave packets brings us into the true physical jungles of the wave particle dualism. Brownian motion, while easy enough to understand without visualization, offers interesting experiments due its "time machine". There are also many less popular but also interesting topics in this category.
Near 30 topics can be directly or indirectly assigned to this category, too many for talking about them all in the front page. Please visit the category page to see them all.
You can just play with applets from this mystery collection, as children do with mandelbrot set. This last group is the attic of the project, and we do not expect to have a lot of visualizations there.