|
|
| Line 1: |
Line 1: |
| {{demoscene}}
| | The name of the author is Jayson. North Carolina is where we've been residing for many years and will by no means move. She works as a journey agent but quickly she'll be on her own. What me and my family love is bungee jumping but I've been taking on new things recently.<br><br>Visit my web site - [http://www.edmposts.com/build-a-beautiful-organic-garden-using-these-ideas/ free psychic] |
| | |
| {{Unreferenced|date=April 2010}}
| |
| {{Citations missing|date=April 2010}}
| |
| | |
| The '''plasma effect''' is a computer-based visual effect animated in real-time. It uses cycles of changing colours warped in various ways to give an illusion of liquid, organic movement. | |
| | |
| [[Image:Plasma effect.jpg|200px|thumb|left|A still screenshot of a typical plasma effect.]]
| |
| [[File:-PLASMA-ColorCycling.Gif|200px|thumb|left|Animated color cycling feature as in Fractint]]
| |
| Plasma was probably invented by [[demoscene|demo coders]] for use in their [[Demo (computer programming)|demos]] where the effect was heavily used, especially in the early 1990s. The effect was particularly common on the [[Commodore Amiga]] where it could be implemented very efficiently by using the features of the proprietary display hardware. Plasma can also be implemented easily in software rendering by using sinus tables and [[palette (computing)|pseudocolor palettes]], and it has also been the first true demo effect for many beginning PC democoders.
| |
| | |
| The fractal software [[Fractint]] also incorporates an algorithm known as "plasma", which, when combined with the color cycling feature of the software, can provide a result which resembles a typical plasma effect used in demos. The technical basis, however, is completely different, and a color cycling plasma is somewhat less dynamic than a demo plasma.
| |
| | |
| == Synopsis ==
| |
| | |
| [[Image:AAlib-gradient.png|250px|thumb|left|A plasma effect rendered in [[ANSI art]] by the [[AAlib]] library.]]
| |
| | |
| As there are many "hacked" approaches for implementing a plasma effect, this outline of an algorithm will just describe the theoretical basis for the effect. In order to achieve a sufficiently fast and good-looking real-time implementation (especially on the limited hardware available at the time this effect was at the height of its popularity in the 1990s), one would often do "non-correct" approximations to this algorithm. This, however, can often be done without noticeable visual differences.
| |
| | |
| This algorithm is given in two dimensions, but could easily be adopted to any number of dimensions for any number of color channels.
| |
| | |
| Let <math>f(x, y)</math> be a multi-frequency noise function of two 2 variables (''e.g.'', a [[perlin noise]] function). Let each color component <math>c</math> at the pixel <math>(x, y)</math> be a linear function of the expression <math>\sin(f(x,y) \cdot \omega_c)</math>.
| |
| | |
| == See also ==
| |
| | |
| [[Diamond-square algorithm|Plasma fractal]] is a fractal that the plasma effect can be applied to with nice results.
| |
| | |
| == External links ==
| |
| * [http://www.anfyteam.com/anj/plasma/plasma.html Java applet demonstrating plasma effect]
| |
| * [http://www.bidouille.org/prog/plasma Page explaining how the effect is built and including a JavaScript animation]
| |
| | |
| [[Category:Demo effects]]
| |
The name of the author is Jayson. North Carolina is where we've been residing for many years and will by no means move. She works as a journey agent but quickly she'll be on her own. What me and my family love is bungee jumping but I've been taking on new things recently.
Visit my web site - free psychic