THE JAVA APPLETS ANY SERIOUS WEB DESIGNER SHOULD HAVE

INTRODUCTION

This applet is a scroller which will trace the contour of an image and use this borderline as the path for a scrolling text. The contour is traced using an image filtering technique. The applet has the following features:

• The contour is created by removing a specifyable color and setting a filter threshold factor. If preferable, transparent GIF89 images can be used instead.
• Supports a background image.
• Specify font type, font size and font style.
• You can specify the text color and background color.
• Confirmed compatibility with Netscape versions 3.01 to 4.5 and Microsoft Internet Explorer versions 3.0 to 4.1 for Windows 95/98/NT4. Also compatible with Internet Explorer 4.5 for Macintosh.

Before using this applet you must read the license agreement.

APPLET INFORMATION

DEPENDENT FILES

The following files must be included with the applet in order for it to function properly:

mmcontourscroller.class

GENERAL PARAMETERS

This applet is configurable with normal HTML applet parameters. The first thing that must be done is to configure the applet main tags:

<APPLET CODE="mmcontourscroller.class" WIDTH=320 HEIGHT=200>
</APPLET>

As you can see, the size in the example is 320x200 pixels. You can change the dimensions to whatever size you wish. However, you take note that sometimes a big applet requires more processing power which may be hard for some computers. The following parameters may not be changed:

<PARAM name="mandomartis0" 
value="This is an applet from Anibal's Essential Applets package">
<PARAM name="mandomartis1" 
value="It was developed by Anibal Wainstein / Mandomartis">
<PARAM name="mandomartis2" 
value="Get it at http://www.mandomartis.com/essentialapplets/">

These are Mandomartis credits are are used to identify the applet. The following parameter controls the general frame delay in milliseconds, and thus the frames per second (FPS). The default value is 70:

<PARAM name="delay" value="70">

THE MESSAGE

Write the message you are going to use in the "message" parameter, like this:

<PARAM name="message" value="Greetings from John">

FILTERING THE IMAGE

Here, we urge you to take a close look at the applet example and look at the spheres.jpg image.

To be able to use this applet. You must specify a foreground image:

<PARAM name="foregroundimage" value="spheres.jpg">

The image should have a bottom or top area of a particular color that you want to filter away. The scrolling text will be used to scroll in the filtered area. Note that this image will be automatically resized to fit in the applet window. The most important parameter here is the "backgroundcolor" parameter:

<PARAM name="backgroundcolor" value="000000"> 

In the example above we assume that the color of the area is black "000000", such as it is in the spheres image. However you should change this color to match the color of your image. The background color will also be used to fill the filtered area if you are not using a background image, providing you are not using a background image. Of course, you will not be able to select the exact background color matching your image. This is where the "filterfactor" parameter will help you:

<PARAM name="filterfactor" value="10">

By specifying a small threshold value for the filter, you can be sure that the applet will ignore colors with similar shades. For instance, if you have a yellow background where the colors range from "ffff00" to "efef00", then you should set this value to be about 20, to cover these shades of yellow. This value should not be too large.

By setting the "filtertoparea" parameter to "yes", you can get the applet to filter away the top area of the image. In the spheres example this parameter must be set to "no":

<PARAM name="filtertoparea" value="no">

If you want to use transparent images instead, then simply make sure that the area you want to filter away is transparent. The filter parameters, except the "filtertoparea", will be ignored if you are using a transparent image.

SELECTING COLORS

With the "textcolor" parameter you can specify the color of the scrolling message:

<PARAM name="textcolor" value="ffff00">

FONT PARAMETERS

The font parameters affect the font type ("font" parameter), font size ("fontsize" parameter) and the font style ("bold" and "italic" parameters):

<PARAM name="font" value="Helvetica">
<PARAM name="fontsize" value="16">
<PARAM name="bold" value="no">
<PARAM name="italic" value="yes">

The font types can be "TimesRoman", "Helvetica", "Courier" and "Dialog". If you want the font style to be bold or italic then specify the value "Yes" on these parameters.

OTHER PARAMETERS

The background image can be specified by the "backgroundimage" parameter:

<PARAM name="backgroundimage" value="background.gif"> 

This parameter overrides the "backgroundcolor" parameter's effect if you specify it. By leaving this parameter blank you can disable the background image and use the background color instead. The background image will be resized to fit the applet window, automatically.

Use the "speed" parameter to increase the scroller speed:

<PARAM name="speed" value="3">

The "scattering" parameter will affect path of the scrolling text across the image:

<PARAM name="scattering" value="5">

EXAMPLE OF A FULL CONFIGURATION

The following HTML text is an example of an applet configuration:

<APPLET CODE="mmcontourscroller.class" WIDTH=320 HEIGHT=200>
<PARAM name="mandomartis0" 
value="This is an applet from Anibal's Essential Applets package">
<PARAM name="mandomartis1" 
value="It was developed by Anibal Wainstein / Mandomartis">
<PARAM name="mandomartis2" 
value="Get it at http://www.mandomartis.com/essentialapplets/">
<PARAM name="delay" value="70">
<PARAM name="font" value="Helvetica">
<PARAM name="fontsize" value="16">
<PARAM name="bold" value="yes">
<PARAM name="italic" value="yes">
<PARAM name="textcolor" value="00ff00">
<PARAM name="speed" value="5">
<PARAM name="scattering" value="5">
<PARAM name="filterfactor" value="10">
<PARAM name="backgroundcolor" value="000000">
<PARAM name="filtertoparea" value="no">
<PARAM name="foregroundimage" value="spheres.jpg">
<PARAM name="backgroundimage" value="">
<PARAM name="message" 
value="Hello and welcome to Anibal's Essential Applets">
</APPLET>

© Copyright 2001-2005 Mandomartis Software Company