[jitter] Re: Is This Possible For Beginner?

Right I see.

I suppose it depends upon how you want it to be controlled. The jitter part of all this is easy as it is really just a matter of updating and drawing a line - which is a simple command. The logic part is the tricky bit. 

If you want it to move in set increments you will need to consider that a note could be pressed at any time (I'm assuming that you want this to be part of a performance tool?). If this is the case do you want to:

a) have the line constantly moving - if so the chosen note just changes the direction of movement.

In this scenario the movement will need to be calculated continuously at regular intervals - e.g use a metro to add/subtract appropriate values to/from the position indefinitely (every 20ms for example) and just alter the polarity of the added/subtracted value for x and y to specify direction.

or

b) have the line move the a set amount per note played in a direction specified by the note - in which case does the note interrupt the current movement or does it wait until the movement from the previous note before it takes effect?

In this scenario the same metro setup will be needed to bang through the calculation but you will need to set it to move 'x' amount of times until the desired distance has been achieved. So moving 100 pixels over 100 ms will require a metro at 10ms to add 10 to the current position each time - test it to see if 100 has been added and then turn off the metro. (maybe use in conjunction with a counter - which can be rest to zero if a new note is played if thats the way you want to work it) 

Any good?

Andy