you will want to create a variable for servo position. This variable with be defined by mouseX this is the position on the mouse on the X axis. (you may want to draw a rectangle 180 long to give you an idea of where to place the mouse)

You will also need a constraint which will limit the variable from 0-180. 

Then for the servo you tell the position to be defined by the variable for servo position.

I realise this is a bit vague but if you dont understand I could try and write the start of the code tomorrow if you are still stuck.

Craig

I only don´t know the commands in Processing for the Arduino. I only know a few like [ Arduino.digitalWrite() or Arduino.LOW ]. Actually I know only 3-5 commands. Because I am a beginner with Processing :-)

What I need is a list with the basic commands for Arduino and an example.

And I want to make in Processing that:

I draw a square and if I push my mouse the programm should check the value on the x ax 

So my square is 179 pixel big.

The value from the mouse (0-179) must send to the Servo and it turn to that position.

Can you make an example :=)

And first i upload ServoFirmata