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Installation

Content
Installing

 

User Guide

Introduction
A first approach
Example 1
Example 2
Example 3
Example 4
Example 5
Example 6
Creating a component
Creating a DataServer

 

Developer Guide

Developer guide
Classes reference

 

Examples

Running the applet

 

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Example 2: an input device with a single line of code

For this example, open the configuration named "grid". It is also a dgsl script which contains, aside of the component configuration part, only one line of effective dgsl code:

image $level1@level1 $level2@(;level2;0<>300) pointer.gif

As you can see, this line draws the image pointer.gif on a position which depends on level1 and level2 as defined by $level1 and $level2 (if these variables are not set to a value, you won't be able to see the arrow. To set some values to level1 and level2, you can simply create two TextFields in the main window and connect them to level1 and level2). But you can also see that the X and Y parameters are connected, on the output, to the same variables (@level1 and @(;level2;0<>300)). By doing so, you can move the arrow around in the grid. To move the arrow, click on it and keep the mouse button pressed while moving the mouse. When you release the button, level1 and level2 are set to the new X and Y position of the arrow. You'll see that you can not move the arrow to the bottom of the grid. This is because the Y position has a lower limit of 0 and a higher limit of 300.

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If you have enabled the communication with the server and if you have write access to the server (see "Installing the package"), level1 and level2 will be changed locally and on the server.
If you have enabled the communication with the server but you do not have write access to the server, then level1 and level2 will soon be set to the values they have on the server.

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author: F.Momal - CERN - LHC division - IAS group