UDP Send/Receive from Grasshopper to Processing

Replies to This Discussion

Permalink Reply by Peter Ayad on April 26, 2014 at 7:47am

Hi,

i tried sending a longer string from grasshopper and then separate in processing.

each value will be separated from the other value with any char that you won't use (you are sending numbers in the string so i will separate values by the char 'x') 

for example

value1=123 and value2=456 and value3=789 

will be 

"123x456x789"

and in processing you will have to split the message whenever the program finds the char 'x'

String message = new String(data);  

String[] messageParts = message.split("x");

from here you can read any part from the array

float value1 = Float.valueOf(messageParts[0]).floatValue();

float value2 = Float.valueOf(messageParts[1]).floatValue();

float value3 = Float.valueOf(messageParts[2]).floatValue();

i am not really sure if it is the fastest way.

check the attached files

Attachments:

• udpsendreceive - edit.ghx, 944 KB
• UDP1_1_edit.pde, 1 KB

Permalink Reply by George L on April 26, 2014 at 8:19am

Hi Peter,

Thank you so much for your help! That helps me a lot. Just a question. Is not possible to have an array to store the values coming from grasshopper instead of store one by one?

For example:

value[i] = Float.valueOf(messageParts[i]).floatValue();

Thank you again

George

Permalink Reply by Peter Ayad on April 26, 2014 at 9:00am

i modified the last gh file ... i think this way is easier 

for processing .. the code you retrive from this line

String[] messageParts = message.split("x");

is an array of string you can convert an array of string to an array of floats this way

String[] messageParts = message.split("x");

float[] value = new float[messageParts.length];

for(int i=0;i<value.length;i++)
      value[i] = Float.parseFloat(messageParts[i]);

now value contains all the values coming from the string 

Permalink Reply by George L on April 26, 2014 at 9:55am

Thank you Peter so much Peter now I got it. The way you show me in Grasshopper is much easier since I will have many values.

Thanks

George

Permalink Reply by George L on April 28, 2014 at 12:18pm

Hello,

I have another issue. I like to send the values from Grasshopper sliders to Processing and do some calculations inside Processing.

After that sending back the values from Processing to Grasshopper and update my sliders values with the new values from processing. 

Actually what I'm doing is a loop until a number reaches 0. For example starts from 5 and follows this loop until get 0. Any idea of how to update sliders value in each loop and send it back?

Permalink Reply by Peter Ayad on April 29, 2014 at 2:34am

i think it would be much simpler if you stated your initial values in processing; that way you won't have to change the value of the sliders after the first communication (which i don't think it'd be possible) instead of the sliders you will read the input values from the message.

Permalink Reply by George L on April 28, 2014 at 1:47pm

I need multiple loops until I my value reaches 0 and then I need to stop the communication. Is that possible?

Permalink Reply by Peter Ayad on April 29, 2014 at 2:22am

have you tried to build the send command inside the loop in processing ? 

for example:

for(int i=20;i>=0;i--){

    // rest of the code here //

    udps.send( message, ip, port );

}

whenever the loop ends it will stop sending messages ... 

Permalink Reply by George L on April 29, 2014 at 8:10am

Hi Peter,

Thank you for your answer.

Yes I have try that but the main problem is the other way around. I like to control the values sent from grasshopper to be send only once.

Now Grasshopper sends continously the slider values and I cannot control the values since after the calulations in processing it gets back the slider value.

Permalink Reply by George L on April 29, 2014 at 12:43pm

Anyone knows how to send data from grasshopper to processing just once? I'm sending values from a slider and I'm doing some calculations on Processing until I reach a specific number but it doesn't work since each millisecond grasshopper sends the original values to processing.

Permalink Reply by vapeur on May 30, 2018 at 9:07pm

Hi I was wondering is somebody still on working with UDP? Cos my processing sketch does not work, saying the library is incompatible for the processing version (3.3.6), and I did not find a newer version for the UDP library...