"The Processing language was originally created at MIT as part of the Media lab and Aesthetics and Computation group. They needed a way to bridge the gap between software developers, artists, data visualizers, etc., and to do so in a way that allowed new programmers (or non-programmers) to do complex visual work easily. Processing was built using Java, and can be thought of as a simplified Java, with a simplified Java API for drawing and graphics." (source)
And so it is - with some little tricks.
First, Processing should get initialized in the html page like this
A Processing instance will be created, it can get accessed via Amber in this way:
processing := <Processing.instances>.
After fetching this instance, it can be used like any other Smalltalk Object:
processing background: 224.
processing line: centerX y: centerY dX: myDX dY: myDY.
I converted the clock-example to Amber, you can find it in the Example-section of my Amber Git repo. And maybe soon in the "official" Amber-Examples.