PCA9622_LED8x8  matrix( p28, p27 );     //  for 40pin type mbed
//PCA9622_LED8x8  matrix( D14, D15 );   //  for Arduino type mbed
//PCA9622_LED8x8  matrix( dp5, dp27 );  //  for mbed LPC1114

#include "mbed.h"
#include "PCA9622_LED8x8.h"

//  Choose a target platform from next list
PCA9622_LED8x8  matrix( p28, p27 );     //  for 40pin type mbed
//PCA9622_LED8x8  matrix( D14, D15 );   //  for Arduino type mbed
//PCA9622_LED8x8  matrix( dp5, dp27 );  //  for mbed LPC1114

float func( float x, float y, float t );    //  function to make 8x8 image

int main()
{
    float   image[ 8 ][ 8 ];  //  
    int     count   = 0;
    
    matrix.start();

    while(1) {
        
        //  making 8x8 image to "image" array
        for ( int i = 0; i < 8; i++ )
            for ( int j = 0; j < 8; j++ )
                image[ i ][ j ]   = func( i, j, count * 0.2 );

        //  set the image into library internal bufer
        matrix.set_data( image );

        count++;
        wait( 0.05 );
    }
}

float func( float x, float y, float t )
{
//#define     DISPLAY_OFFSET  3.5
#define     DISPLAY_OFFSET  0
#define     SIZE            0.3

    float   s;
    
    x   = (x - DISPLAY_OFFSET) * SIZE;
    y   = (y - DISPLAY_OFFSET) * SIZE;

    s   = cos( powf( x * x + y * y, 0.5 ) - t );
    return ( powf( s, 4.0 ) );
}