Color Gradients 1-6

clrGrad_1_6.pde

color green = 0x3f00ff00; 
color red = 0x3fff0000;

float centerXStart = 256;
float centerYStart = 128;
float centerXStop = 128;
float centerYStop = 64;
float innerDiam = 32; 
float outerDiam = 512;
float detail = 30;

size(512, 256);
noStroke();
background(0xffffffff);

for (float i = outerDiam, step; i >= innerDiam; i -= detail) {
  step = (i - innerDiam) / (outerDiam - innerDiam);
  fill(lerpColor(green, red, step));
  ellipse(lerp(centerXStart, centerXStop, step), 
    lerp(centerYStart, centerYStop, step), i, i);
}