Fieldlines Java Applet

The fieldlines demo is based on the fishtank applet. Based on an N-Body problem and depending on the applet configuration fieldlines are drawn either starting from a fixed grid or directly at the charges. Calculation of fieldlines is done by using tracer elements and tracking their way a predefined number of steps. If you do it with enough tracers you get the impression of fieldlines.

Download and Useage

Download icon Download jar file
Download source code (requires Netbeans)

In order to use the applet add the following lines to your html code:

  <object classid="java:fieldlines.class" type="application/x-java-applet" width="400" height="400">
    <param name="code" value="fieldlines.class"/>
    <param name="archive" value="JFieldlines.jar"/>
    <param name="sleep" value="1">
    <param name="fixed" value="true">
    <param name="length" value="100">
    <param name="step" value="10">
    <param name="number" value="10">
    <param name="preview" value="false">
  </object>

The following table lists the applet parameters and their meaning.

Parameter	Meaning
fixed	If this is true fieldlines start from a regular grid if it is false they start directly at the charges.
length	The total number of steps used for tracing fieldlines
number	The number of charges involved
sleep	time to wait after each frame (in milli seconds)
step	If parameter fixed==true this is the spacing between the fieldline origins
preview	If this value is true the applet looks like an image only moving when the mouse is over the applet.