A simple example

To begin, let's take a look at a simple example that draws two intersecting rectangles, one of which has alpha transparency. We'll explore how this works in more detail in later examples.

  def drawfun
    context = Gdk.cairo_create(@window.window.not_nil!)
    context.set_source_rgb(1, 0, 0)
    context.rectangle(10, 10, 50, 50)
    context.fill
    context.set_source_rgba(0, 0, 1, 0.5)
    context.rectangle(30, 30, 50, 50)
    context.fill

  end

This example looks like this: