Help with Opacity(Transparency)

[glv]

Hello,

I experimented a little!

Example code:

function setup() 
  {
  createCanvas(750, 200);
  }

function draw() 
  {
  background(255); // Try backgrounds other than white and see what happens.
  
  textAlign(CENTER, CENTER);
  textSize(48);
  
  blendMode(BLEND);  // Default
  
  // Text behind circle  
  fill(0);
  text("25", 150, 100)
  fill(255, 0, 0);
  circle(150, 100, 70);
  
  // Text on top of circle  
  fill(255, 0, 0);
  circle(300, 100, 70);
  fill(0);
  text("25", 300, 100)
  
  fill(0);
  text("25", 450, 100)
  fill(255, 0, 0, 64);  //75% transparency with white background
  circle(450, 100, 70);
  
  blendMode(DARKEST);
  smooth();
  fill(0);
  text("25", 600, 100)
  fill(255, 0, 0, 128);
  circle(600, 100, 70);    
  }

:)