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<h3>Functions</h3>

<p>The draw_target() function makes it easy to draw many distinct targets.

Each call to draw_target() specifies the position, size, and number of

rings for each target.</p>

<p><a href="http://processing.org/learning/basics/functions.html">Original Processing.org Example: Functions</a><br>

<div class="learning-demo"><script type="application/processing">

void setup()

size(200, 200);

background(51);

noStroke();

smooth();

noLoop();

void draw()

draw_target(68, 34, 200, 10);

draw_target(152, 16, 100, 3);

draw_target(100, 144, 80, 5);

void draw_target(int xloc, int yloc, int size, int num)

float grayvalues = 255/num;

float steps = size/num;

for(int i=0; i<num; i++) {

fill(i*grayvalues);

ellipse(xloc, yloc, size-i*steps, size-i*steps);

}

</script><canvas width="200" height="200"></canvas></div></p>

<div style="height:0px;width:0px;overflow:hidden;"></div>

<div class="code"><pre name="code" class="processing">// All Examples Written by Casey Reas</a> and Ben Fry</a>

// unless otherwise stated.

void setup()

{

size(200, 200);

background(51);

noStroke();

smooth();

noLoop();

}

void draw()

{

draw_target(68, 34, 200, 10);

draw_target(152, 16, 100, 3);

draw_target(100, 144, 80, 5);

}

void draw_target(int xloc, int yloc, int size, int num)

{

float grayvalues = 255/num;

float steps = size/num;

for(int i=0; i&lt;num; i++) {

fill(i*grayvalues);

ellipse(xloc, yloc, size-i*steps, size-i*steps);

}

}</pre></div>