Simon

Hey guys, I was wondering if someone could help me out with using js in MAX? I dont fully get how it works...

Right, here's what I want to do... (maybe theres a better way to go about it?)

I have a VVVV patch with objects moving around. I want to quantize the screen to use it as a sort of algorithmic composition procedure, with Y being a user-definable pitch register range (eg 1 to 6 will be C1 to C6) and X being the notes.

So I was thinking the js object might be the best thing to use? Here's what I got...

- Check Boid Position on Screen in steps (number determined by reg range)

- If position is inside step, reg = current reg

I am just wondering how this all 'works', ie :

- do I have to trigger the code or does it run everytime it gets a new set of values

- am I mad using js, is there an easier way?!

Any help would be much appreciated! Still quite the max newbie.

- Check Boid Position on Screen in steps (number determined by reg range)
- If position is inside step, reg = current reg
- else increment current reg and step

--not sure how to do these yet--
read in Reg_Min
read in Reg_Range
read in x
--------------------------------

var Curr_Reg=Reg_Min;
var step = 1/(Reg_Range/2);

    if (x
        Reg=Curr_Reg; 
        i=1;
    }
    [else {
        Curr_Reg=Curr_Reg+1;
        i=i+step;
    } ]
}

- how do I create inlets / outlets
- do I have to trigger the code or does it run everytime it gets a new set of values
- am I mad using js, is there an easier way?!

javascript-in-max

Firstly, there is a dedicated javascript forum which you can get to from the forum home page, if you're looking specifically for js help then that's the place you're most likely to get answered.

To answer a few of your javascript questions have a look at the "javascript in max" topics from the main help page. It will get you clued in on how to define inlets and call functions. The javascript pdf that came with the max 4 documentation is pretty useful too. Here's some pointers:

if (inlet == 0) // if in first inlet do stuff in { }

function boid (n,x,y) // called when [js] receives "boid" message

{ post ("boid: "+n+"nx: "+x+"ny: "+y+"n"); } // args after "boid" are now variables n, x and y.

You could definitely do this in javascript if you wanted to, although it could be done with regular max objects if you are more comfortable using them. How are you getting the data from vvvv and what format is it in when it enters max?

if (inlet == 0) // if in first inlet do stuff in { }
{ post ("woo!"); }

function boid (n,x,y) // called when [js] receives "boid" message
{ post ("boid: "+n+"nx: "+x+"ny: "+y+"n"); } // args after "boid" are now variables n, x and y.

How do I go about assigning an inlet to a certain value in the code?

values from boids patch are gonna be x,y positions from -1 to 1 and theres a register range value the user inputs in max.

My javascript is rusty to say the least but I am not sure how I could go about implementing this with max objects if the user can change the range (without it getting hugely messy)!

Sorry, I didn't realise there was a java thread! Will post this there.

The javascript forum is a good place to search for help too. I can see why you'd want to use javascript, I haven't been using it for long but for some tasks it makes things a lot simpler.

If I were you I'd [pack] the floats into a list and then [prepend boid]. Then in the [js] I'd have a "boid" function like this:

From inside the boid function you can call the variables x and y which will be the two floats you had originally. Of course, you could do it other ways, for example: sending the floats into two seperate inlets and do everything in javascript, but I feel this way is a bit simpler to start with. If you get stuck then post your patch and js code and I'll take a look.

Will give it a go and see what I can come up with.

Hey man, here's what I got... Not doing something right anyway!

If you get a free second to have a look I would really appreciate it but if not, dont worry!

swarmintellingence wrote on Sat, 28 March 2009 14:15

Not totally sure what you're after, but a couple things to get you further along. See comments in the .js below.

You probably can do this just fine with Max objects, but trying it in different ways can be helpful too. Sometimes code is just what you need.

function Reg_Quant(y, Reg_Range, Reg_Min)

so then you input the list: Reg_Quant 0.5 88 128 (example) just as you've done with "prepend Reg_Quant"

outlet(0,Curr_Reg); // instead of "return" use outlet command to get data out

swarmintellingence wrote on Sat, 28 March 2009 14:15Hey man, here's what I got... Not doing something right anyway!

function Reg_Quant(y, Reg_Range, Reg_Min)  

/* need to declare it as a "function"
 so then you input the list: Reg_Quant 0.5 88 128 (example) just as you've done with "prepend Reg_Quant"
*/

{
    var Curr_Reg=Reg_Min;
    var step = 1/(Reg_Range/2);
    var i= -1;

        if (y
            Reg=Curr_Reg; 
            i=1;
            }

        else {
            Curr_Reg=Curr_Reg+1;
            i=i+step;
            } 
        }

    outlet(0,Curr_Reg);  // instead of "return" use outlet command to get data out
}


What exactly are the variables "Reg_Range" and "Reg_Min", some sort of scaling for the size of the boids canvas? It might help to know what they're for and some typical or default values so we can read through your code properly.

Apart from that, CJ's comments will help you get stuff in and out of your patch which was your main problem. Hopefully with that out of the way you'll find things go a bit smoother.

Ye sorry reg range is the range of pitch class (the y axis), which is adjustable, steps in x axis aren't.

Think you have steered me in the right direction now, my main problem was getting stuff in and out.

Javascript in Max