LED Panel with 64x32 Leds controlled by Arduino board

@JumJum ... or use this function to draw circle:

function circle(xm, ym, r) {
      var x = -r,
        y = 0,
        err = 2 - 2 * r;
      do {
        g.setPixel(xm - x, ym + y);
        g.setPixel(xm - y, ym - x);
        g.setPixel(xm + x, ym - y);
        g.setPixel(xm + y, ym + x);
        r = err;
        if (r <= y) err += ++y * 2 + 1;
        if (r > x || err > y) err += ++x * 2 + 1;
      } while (x < 0);
}

The 'spikes' come from the optimized algorithm that can handle ellipses and circles incl. fill (4 auf einen Streich).

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