Processing 1.0 - Processing Discourse - draw values of an 2D array

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Index › Programming Questions & Help › Syntax Questions › draw values of an 2D array

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draw values of an 2D array (Read 600 times)

TiPpFeHlEr

draw values of an 2D array
Feb 6^th, 2010, 1:30am

hi,

i've a little problem.
i have a 2D array, i ad every frame an value to this array.
now i whant to draw this array.
the array has 500 col's and 15 row's, each col has 15 row's.
by row is y-axis, and col is the x-axis.

Code:

int colmax = 500;
int rowmax = 15;
int[][] sgram = new int[rowmax][colmax];
int[] sgram2 =new int[rowmax];

int col;
int leftedge;
int b;
int currMaxVal;
int maxValPos;

for(int i = 0; i < rowmax ; i++)
  {
    sgram2[i] = (int)Math.round(100*fft.getBand(i));
    if ((int)Math.round(fft.getBand(i)) > (currMaxVal)){currMaxVal=((int)Math.round(fft.getBand(i)));
    maxValPos = i;
    }
    }
  noStroke();
   colorMode(HSB, 140);

   color a = color(maxValPos, currMaxVal, currMaxVal);
    
    noStroke();
   
  currMaxVal =0;
  maxValPos = 0;
 
sgram[b][col] = (a);

   b=b+1;
  if (b==rowmax){b=0;

  // next time will be the next column
  col = col + 1; 
  // wrap back to the first column when we get to the end
  if (col == colmax) { col = 0; }
}

i will draw the y-axis everytime i ad a new value.
when the row iss full, i will shift it 1 step left and begin to draw a new row.

i tried it like "full spectrum analyz" sketch. but it dont realy work fine.
Code:

// Draw points.  
  // leftedge is the column in the ring-filled array that is drawn at the extreme left
  // start from there, and draw to the end of the array
  for (int i = 0; i < colmax-leftedge; i++) {
    for (int j = 0; j < rowmax; j++) {
	stroke(sgram[j][i+leftedge]);
	point(i,height-j);
    }
  }
  // Draw the rest of the image as the beginning of the array (up to leftedge)
  for (int i = 0; i < leftedge; i++) {
    for (int j = 0; j < rowmax; j++) {
	stroke(sgram[j][i]);
	point(i+colmax-leftedge,height-j);
    }
  }
  // Next time around, we move the left edge over by one, to have the whole thing
  // scroll left
  leftedge = leftedge + 1; 
  // Make sure it wraps around
  if (leftedge == colmax) { leftedge = 0; }
}

did anybody have a sample??

regars maik

TiPpFeHlEr

Re: draw values of an 2D array
Reply #1 - Feb 7^th, 2010, 1:01am

wow i made it Cheesy

here my code.
Code:



 
import ddf.minim.analysis.*;
import ddf.minim.*;
 
Minim minim;
AudioInput in;
FFT fft;
int colmax = 100;
int rowmax = 25;
int[][] sgram = new int[rowmax][colmax];
float[] sgram2 =new float[256];

int col;
int leftedge;
int b;
float currMaxVal;
int maxValPos;


void setup()
{
  frameRate(63);
  size(500, 125);
  
 // set colormode
 colorMode(HSB, 255,255,255,255);
 
 // get the audio
  minim = new Minim(this);
  in = minim.getLineIn(Minim.STEREO,2048);
 fft = new FFT(in.bufferSize(), in.sampleRate());
  fft.window(FFT.HAMMING);
}
 
void draw()
{
  background(0);
  
  // perform a forward FFT on the samples in the input buffer
  fft.forward(in.mix);
  // fill array with spectrum
  for(int i = 0; i<256 ; i++)
  {
    sgram2[i] = (fft.getBand(i));
    if ((fft.getBand(i)) > (currMaxVal)){currMaxVal=((fft.getBand(i)));
    maxValPos = i;
    }
    }
    //set the color by: highest value and the freq-band
    color a = color(maxValPos,255 ,currMaxVal );
    // set values to zero
    currMaxVal =0;
    maxValPos = 0;
  //fill the last column of the array with the color
    sgram[b][99] = (a);
    // count up the rows
    b=b+1;
    // when row is full, shift array 1 step left
  if (b==rowmax){b=0;
  for(int z = 0; z < 99 ; z++){
    for(int b = 0;b < 25; b++){
    sgram[b][z]=sgram[b][z+1];
 }
  }
  // count up the column
  col = col + 1; 
  // wrap back to the first column when we get to the end
  if (col == colmax) { col = 0; }
  // draw the array ;)
}
for (int i = 0; i < colmax; i++) {
    for (int j = 0; j < rowmax; j++) {
	
	fill(sgram[j][i]);
	rect(i*5,height-(j*5),5,5);
    }
  }
}
 
 
void stop()
{
  // always close Minim audio classes when you finish with them
  in.close();
  minim.stop();
 
  super.stop();
}

regards maik

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