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Tom's Plasma! by Tom Dibble, Copyright 1994 *TPLAS MANUAL* ----------------------------------------------------------------- TPLAS (T '-Plaz): [Abbr. "Tom's Plasma"] Screen effects program by Tom Dibble. ----------------------------------------------------------------- AUTHOR'S NOTE: Thank-you for taking a look at my little program! I realize there are plenty of programs at these shareware sites worthy of a second look, yet you devoted a few moments of your time to evaluating my efforts. For that I am certainly appreciative, and I hope you are not disappointed in your expectations. This program started out as a trivial exercise in creating a Plasma Fractal and employing a technique called "Swimming" on that fractal (see the Tech section for more info). Further effects were then added, one atop the other, until ... The result is a rather unique program which in function fits somewhere between the "kaleidoscope" screen effects programs such as Dazzle (from Worldwide Microtronics, Inc) and screen "saver" programs such as AfterDark (from Berkeley Labs). To keep with the original purpose of Tom's Plasma, the release of this revision contains the entirety of the source code to create Tom's Plasma revision 1.1, which merely generated the plasma fractal and then employed the "swimming" effect. Copyrights on this code are explained in the TPlas11.DOC file. The document and source code files are all included in the Zip file "TPlas11.ZIP", which should be "un-zipped" using "PKUnzip" version 2.0g or newer, or using a version of the free "Unzip" newer than late 1993 (compatible with PKUnzip 2.0+). Revision 2.0 of Tom's Plasma is released as Shareware, in hopes of regaining at least *some* compensation for the many hours spent improving it, mostly in the form of knowing people are actually using it. I wrote it with no such hopes in mind, purely as an exercise in programming, and so the price I am charging is deliberately low (well below those asked for by Dazzle and required by AfterDark), at $10.00 (US). Benefits of registration include: That warm feeling of knowing you've supported Shareware! A Registered Version of the program, which includes the Manual and Semi-Automatic modes detailed below. Optional Full Source Code (of interest to programmers out there). Interest in source code must be explicitly stated on the order form. Well, that's all the general stuff *about* this program. I suggest you read on for more details concerning how to use the program, especially the "Keys" and "Caveats" sections. IF YOU ARE A BUSINESS: If you are a representative of a business, you may use the Demonstration version of Tom's Plasma ("Demo.COM") at no cost, but only on business computers in a public setting. A public setting is defined as anywhere I could get to without having to ask anyone, or in which a large portion of people are gathered. This includes computer shows and demonstration settings as well as some office settings. I offer this version as free to these users because they are, in effect, my advertisement. The Demonstration version is identical to the Unregistered version except that it does not ask you to register (and requires no registration, for qualified users) and includes an identifying effect (which simply says "You are watching a demonstration of Tom's Plasma"). Demonstration versions which include a reduced set of effects (such that the effects which are slow on a specific computer are not generated) *may* be obtained by personal correspondence with me. The cost is $10.00 (US), just like the Registered version; however, these programs suffer the same restrictions as the Demonstration Version, and entitle the purchaser to none of the Benefits included in the Registered Version. As a result of being analogous to the Demonstration Version, on the other hand, such reduced-effect versions of Tom's Plasma may be freely distributed, so long as they are clearly identified as reduced-effect versions. Details concerning the distribution of these versions will be included with the program or available pre-purchase upon request. This offer is separate from all claims concerning Revision 2.0 of Tom's Plasma, and availability is dependant on my time and whim. FILES WHICH SHOULD HAVE BEEN INCLUDED: TPLAS.COM The program itself, unregistered. TOMSPLAS.DAT Data file for the program. INSTALL.BAT Installation batch file. DEMOINST.BAT Demo installation. TPLAS11.ZIP Old version+source. TPLAS.DOC This file. REGISTER.DOC Registration file. TECHNICAL STUFF NO ONE WANTS TO KNOW: Well, you asked for it! This is Tom's (that's me) Plasma. It puts a quick plasma fractal (*NOT* a sin/cos function!) up on screen, then swims the fractal in a center window while cycling the colors. That's it. But I think that deserves some explanation, don't you? First off, what is plasma? The plasma display implemented here falls into a class of images called "Fractals". A fractal can be zoomed in infinitely without loss of detail. Although I do not allow you to zoom in on this particular fractal, the difference between 'fractal plasma' and 'sin/cos plasma' is readily apparent. The only real commonalities is that both generate a fully continuous array of values. In certain applications, the values in the array are used as elevations or terrains of ground. In this application, the values are represented by color. The main difference between these two types of plasma, aside from the obvious visual difference, is that fractal plasma utilizes a random value by its very definition, and therefore is different every time it is generated. Sin/cos plasma is a set function, usually implemented with zero random nature, and therefore does not change between viewings. Okay, so what's this "swimming" thing? For lack of a better name, the display technique I've used here I will refer to as 'swimming'. I originally came across swimming in a program called "JCL-Plasm" by Jeremy Longley. He claims to have copied the effect from Thomas Hagen. Both implementations of swimming involved using a sin/cos plasma rather than a fractal plasma. Swimming can best be described in a simple form of one pointer. A large plasma fractal is generated. Next, a pointer is assigned. This pointer will define the top-left corner of the area of the plasma fractal which is to be displayed. In my implementation, 1/4 of the fractal is displayed at a time in the swimming window, which means the display extends 160 pixels to the right and 100 pixels to the bottom of the pointer. Next, this pointer is moved about on the large plasma fractal. The exact pattern the pointer follows is defined in the data file, and is a pre-generated sin/cos function. Next, we make it twice as complex (and much, much more interesting!) by adding a second pointer. To display both pointers in the same window, we simply add the pixel values together. Since the pixel values have been limited to the range 0-127 we do not have to worry about overflow effects in our adding. An earlier revision (1.1) had this problem, which created a squiggly black line in the middle of the swim window separating pixels of below 255 from those which added to above 255. The result is a window 1/4 the size of the screen which holds a moving, bubbling plasma-looking mess. It's hard to explain; you'll just have to look for yourself! How about the other effects? Though "Swimming" was the original effect in Tom's Plasma, it has been moved aside to make way for many other effects. The first bunch of effects stem from a "flame" algorithm. In real life, the phenomenon of fire is caused by little pockets of air becoming so hot that the atoms within that pocket actually *glow*. Depending on the atoms in the air, many varieties of flame colors may be seen. Perhaps the most common, however, ranges from no glowing through a red glowing, then an orange and yellow glow, and finally a white glow at the warmest points. These heat pockets are created by a strongly exothermic (heat-emitting) chemical reaction as well as by natural convective forces in the air. In real life, they are also caused by embers which get caught in this air stream while burning, but this particular effect is not replicated here. The "flame" effect is firmly based in this explanation of fire, though it is not often explained as such. Our "fire" is in the form of a 320x202 pixel, flat "heat-map". All combustion takes place at the bottom row of the map, and is a result of random "flare-ups" and "flare-downs". The two heat-transfer effects -- convection and conduction -- are treated separately; first all the values of the heat-map are shifted one position upwards, then each value is set to the average of the values surrounding it. To create realism, this latter effect takes the form of the sum of the values above and below, plus half the sum of the values to the left and right, plus the original value, all divided by four. This "heat-map" is then the basis of four different TPlas effects: Inferno, Convection, Melting, and Slime. The first two are direct, theory-based applications, the first making the heat map take on a certain set of colors and overlaying it atop the fractal and the second adding the heat map to the original fractal to create a ripple-like effect. The second two are the result of flipping this "heat-map" upside down and adding or overlaying it with the plasma fractal. Not exactly theory-based, but they look pretty darned cool anyway. Texture mapping is the basis for two more effects. In "texture mapping" the program includes a "texture map" the size of the final picture detailing where from the original picture the final picture should get its value. For instance, the texture map for the top- left pixel might point to position "1,1" in the original picture. The value at point "1,1" in the original picture is then placed in the top-left position of the final picture. Maps exist for two entities: a globe whose surface is made of the original picture, and a tinted crystal globe which refracts the image of the original picture, the colors tinted randomly. These texture maps are both included in the data file and loaded on program start-up. They are the basis for the "Globe (Tinted Crystal)" and "Planet and Moon" effects. The tinting for the globe is done in a rather interesting manner. Each color in the original palette is composed of a red, blue, and green element. Before tinting, I choose a number (0, 1, or 2) by which each of these elements is "shifted" to create the tinted palette. This number corresponds to the power of two by which the original element value is to be divided. For instance, if the 'Red' element is to be shifted by '2', the original red value would be divided by 2-squared (2*2 = 4) to obtain the tinted red value. The result is a tint which lets through a certain percentage each of red, green, and blue, any of 100%, 50%, or 25% of each element of each individual color. The tinting is then done by making colors 0-127 be the un-tinted colors and 128-255 be the tinted colors on screen, and adding 128 to the color value obtained by the globe's texture map. The only negative aspect of this is that if the swim-window was left on screen before the globe started up, it might contain colors above 127, and so the background may have tinted colors in it. Perhaps later versions will solve this problem or avoid it by getting rid of the swim window before the globe starts bouncing, but I like it when the refraction of the globe goes across the hard edges of the swim-window, so I'm not going to take it out yet ... Would you like to do any miscellaneous rambling? Yes I would, thank you! Everything in this little program has been around for a while, as far as I can tell. Certainly isn't cutting-edge! The only really new and original thought which went into this went into speeding up the plasma generation section of the code (by upwards of ten times!). As I have said before, the plasma fractal is based on random values. Random values take a lot of time to calculate because they involve several rather inefficient instructions (namely, multiplies and divides) to be made by the CPU. Since I already had a data file for all of the movement pointers and color palette data (this was before I generated the palette at run-time), I decided I might as well have 64 kilobytes of random values in there as well, pre-computed to save time. But wait! you say. It's different every time, isn't it?!? And the answer is, yes, it is. That is because the random number 'generator' (the code which reads the number from an array in memory) uses a pointer which tells it which number is next in the sequence. At program start-up, this number is initialized to a sum of the hour, minute, second, and hundredths of a second on the system clock (which is also how a random number generator is initialized, btw). Thus, though the sequence is essentially the same every time you run it, the number for each call to the random number generator is different. Secondly (and lastly!) this is my first true assembly program. And it shows. I have been programming in 'C' for a good three years now, but that is hardly the same as programming in assembly, is it? Furthermore, I'm not a computer-science major here in college; I'm a Chemical Engineer. I have taken one class which had anything at all to do with computers the year before last, and learned everything else I know from a few books here and there and, most importantly, the UseNet. Why am I telling you this? So that you know, as you laugh to yourself about my coding style, that I'm certainly not doing this as a living! I coded this because I enjoyed it, and I needed something new and interesting to put up on my screen. If you want to contact me about anything here, this is where I can be reached until May, 1996 (or 1995, if I don't get into the MS program!): tomster@wpi.wpi.edu Or, via the good old post office, at Tom Dibble WPI box 2466 Worcester, MA 01609 My mailbox is always open! Tom Dibble 3-18-94, 7-1-94 BEHIND THE SCENES: TPlas currently resides in about ten assembly files, a few data generation programs (written in 'C'), and this documentation. The assembly files are such that any version (demo, unregistered, registered, or beta) can be assembled at any time (no copying of source code, etc). The registered version is then registered to a specific person and company by way of a 'C' program which changes a few (40) bytes in the beginning of the file. It was written on a 386-SX/16 based computer running DOS. Hence, no support of floating point units for those who care about such things. Assembly is taken care of by Turbo Assembler and linking by Turbo Link, both from Borland International, Inc. Documentation is generated in Word Perfect. ABOUT THE AUTHOR: I'm a student of Chemical Engineering at WPI, in friendly Worcester, MA. Currently I'm a senior, which is why things are running a bit slow right now. Next year I am planning on attending graduate school also in Chemical Engineering, also at WPI, focussing on working with thin palladium-based films for the separation of hydrogen from a reacting mixture. I first sat down to a computer at the end of the summer of 1991, when I was looking into buying this beast next to me. I started programming batch and script files that same year, moving up to 'C' in the spring of 1992 (during finals week). I started programming in assembly because that was the only CS class available when I wanted to take it, in the spring of 1993. A year went by in which I programmed very little in assembly (mostly in 'C'), and then in the early part of this year I began work on Tom's Plasma. I enjoy programming, although I would never dream of doing it as a living. EFFECTS LISTING: This section of the document attempts to give you a bit of a description of the various modes, so you'll know what you are seeing when you see it. Tom's Plasma starts off in Automatic Mode (Semi-Automatic mode in the Registered Version), and can only be switched into another mode if it has been registered. Remember, in this mode, to see another effect hit the space-bar. It may look like nothing is happening; that is because most effects have 'kill- screens' which are activated when the effect exits. If you are really impatient, hit the space-bar again while the kill-screen is in effect and another effect will start up instantly. Plasma Cycling: This is an old and respected effect; colors move through a plasma fractal. Swimming: A small window in the middle of the screen opens up and the plasma in it starts to move/change. Blue Sky: Another window in the middle of the screen, except this time the rest of the screen is blacked out, and the window holds a vision of blue skies and spider-web-like clouds. Inferno: This effect is quite aptly named. It is a nice, big fire set on the bottom of your screen. Slime: Blue-green slime pours down from the top of the screen. Convection: Ripples of convecting heat rise from the bottom of the screen. Melting: The screen ripples and melts from the top of the screen. Globe, Tinted Crystal: A small crystal globe let loose on the screen, bouncing about inside an invisible rectangular border. Planet and Moon: A starry night, a planet spins as its lone moon circles overhead. Yeah, I know the stars wouldn't twinkle if seen from space. And yes, I also know that that moon is far, far too close to the planet. Details, details. KEYBOARD COMMANDS: All Modes: <Enter> Generate a new fractal (random screen clear). <Esc> Get me the heck out of here! 'A' Enter Automatic Mode 'S' Enter Semi-Automatic Mode (Registered Version Only!) 'M Enter Manual Mode (Registered Version Only!) Automatic Mode: <Space> New Fractal Manual Mode: '1'-'3' New fractal of variable smoothness. '1' (rough) is default. <Space> Toggle between Cycle and Swim. 'c' Convection. 'i' Inferno. 'm' Melt Screen. 's' Slime. 'b' Blue Sky. 'p' Planet and Moon. 'g' Globe (clear crystal) Semi-Automatic Mode: (Same as Manual except <Space> same as Automatic Mode) CAVEATS ABOUT KEYBOARD COMMANDS (Please read): You knew this was coming. Some of the effects of Tom's Plasma (all the 'fire' effects, most noticeably) have a 'kill-screen'. When a key is hit to start up another effect and these effects are on screen, they go through their kill-screen. For the flame effects, this kill-screen moves them up (or down) off the screen until they dissapear. For the Planet and Moon and Blue Sky effects this kill- screen throws the screen back and then lets the original colors of the Plasma bleed in. After the kill-screen is done, your key command will be processed. If you are impatient, you may hit the key again, and the kill-screen will end and your key will be processed immediately. If you press a key which is different from the first one you pressed, the *second* key will be processed, *not* the first! The only real difficulty this gives rise to is when a kill-screen is already in effect because the timer went out on the effect. The flames kill screen takes about a second before it is noticeable. Hitting a key twice in this instance may produce unwanted results. For instance, if the kill-screen for 'Slime' just started, and you are in Semi-Automatic Mode, and you press 'i' twice to start up 'Inferno', the first 'i' will *start* 'Inferno', while the *second* 'i' will tell it to restart! You will go directly into the kill- screen for 'Inferno', and then it will start again! This is not a major inconvenience, in most cases. Simply realize, if this happens, that this is what has happened (the machine has *not* decided it just doesn't like you anymore!) Hit the key a third time if necessary to restart the intended effect immediately. ACKNOWLEDGEMENTS: I couldn't have done this without a good lot of support from those around me. First and foremost, Jodi, who put up with me all those times I got an idea and had to put it in *right away*. Next, my "Beta Testers", including Ken Griest, Tom Guyette, and John Henry, who pointed out many an improvement. Finally, all those who praised and criticized the earlier revision, 1.1. If I missed anyone, fill your name in here: _______________ REVISION HISTORY: This is by no means a finished work. I don't know how much more I'll do with it before sending it to the great archive in the sky, but, time permitting, I plan to do a bit more with it at least ... Perhaps I should add some sort of menuing system rather than relying solely upon mnemonics (which are destined to run out soon!). But then, if I ever get that working it's definitely 3.0 time, as that will involve some major changes. Of course, I'm always on the lookout for new effects to try out (suggestions welcome!) Anyway, this is where it is now and where it's been, for what it's worth. October 10, 1994: Revision 2.0 Wow, it's been a while playing with this new version, and it shows! We've gone beyond just Swimming by quite a bit now, and made a product people might actually pay money for! As a result, this revision is not free anymore; a $10 registration fee is required after 30 days, which gives the user lots of extra goodies in the control department as well as full, re- organized, source-code if he so desires. A quick run-down on what was added and approximately when: First came fire. I played around with a demo of a flame algorithm to make it full-screen, then tweaked the algorithm itself until it produced a semi-realistic effect and worked in real-time. This effect takes on four forms in TPlas 2.0: Inferno, Convection, Slime, and Melting. After I had all these effects to play around with, I decided it would be a good idea to have the computer randomize the order in which they were put up on screen. This required some minor re-working of the individual functions to get it to work as a sort of add-on, and later brought on a major restructuring of the program into three major modes. Originally, this was called 'random-mode' and was entered and exited via the 'r' key. This led to great confusion, however, so I added the 'R' key to exit and the 'r' key to enter, and later, when the aforementioned restructuring took place, the 'A' key to enter ('Auto-Mode') and the 'M', 'S', or <Esc> keys to exit. In the restructuring I designated all lower-case keys as effects hotkeys, all upper-case as mode-change hotkeys. A context-sensitive help system (for what little difference in "context" there is) was added during the restructuring. The flames algorithm acquired an exit- screen, where the flames move up the screen with no generation until they disappear. Then I started playing with texture- mapping. The first effect in this area was the 'Globe, Clear Crystal' effect: a bouncing, crystal-clear ball over the Plasma display. Next came the Planet, to which I added stars and an encircling Moon to form the Planet and Moon effect. The plasma fractal was made to wrap-around left to right, top to bottom in order for the planet not to look totally goofy. Somewhere in there I also added the Blue Sky effect and the wash-out screen clear/regeneration sequence. The fly-back exit was added to the Planet and Moon and Blue Sky effects and delays were introduced so that a maximum speed exists for all effects, no matter how fast the computer is. Some keys were reassigned from their early-beta meanings to ones which made sense, and the regeneration effect became preceded by one of four random screen clears ("None", "Fly-Back", "Peel-Back", or "Washout"). Finally, I took the palette out of the data file and generated it randomly, as by this point I was rather sick of the default (revision 1.1) palette, no matter how good it looked. During Beta testing I figured out how to speed up the 'flame' effects with little cost to the effect itself. They now run twice as fast as before, and the release of this revision will be delayed accordingly (I feel it important to include this improvement in this release). As per the request of a certain beta-tester, tinting was added to the "Clear Crystal" globe and the name changed to *Tinted* ("I can't see the little clear ball bouncing around without straining my eyes!"). Told you a lot has happened since last revision! Oh! Packaging! TPLAS20.ZIP contains the entirety of the unregistered version of Tom's Plasma, Revision 2.0, as well as the Demonstration version for use in certain business settings (see above, "If You Are a Business"). Also included is the source for TPLAS11 as an example to programmers of the Plasma effect, such that the TPLAS20 package can replace the TPLAS11 package in circulation with no loss of utility. March 19, 1994: Revision 1.1 Fixed all bugs which had caused anomalies in the fractal (involved overflow of byte values). Shrunk the data file by about 28k by reducing the palette stored to that which we used (four full palettes, not 40). Added lots of keyboard commands: <Space> to toggle swim window on and off, <Enter> for a new fractal; '1', '2', and '3' for progressively smoother fractals ('1' is default). <Esc> is now the only key which exits. This is also the first version to be uploaded for public consumption (I had 1.0 all packaged and ready to go, then decided I'd better fix those bugs ... and I suppose I got carried away ... :-> ). Source code, for what it's worth, included in package, along with data file generator source and executable. Oh, I cleaned up the code a bit as well, using the ARG directive rather than obscure equates, adding a few helpful comments, etc. March 3, 1994: Revision 1.0 The first working version! Start it up, watch it go! Hit any key and it's outta there! Simple, but cool. Generates Plasma Fractal, starts Swimming effect. Then Leaves. Never actually released.