gistfile1.java

import java.awt.Color
import groovy.swing.SwingBuilder
import griffon.builder.gfx.GfxBuilder
import griffon.builder.gfx.swing.GfxPanel

def gfx = new GfxBuilder()
def node = gfx.group {
  antialias true
  ellipse(cx: 150, cy: 150, rx: 100, ry: 50, f: Color.WHITE)
  ellipse(cx: 150, cy: 150, rx: 100, ry: 50, o: 0.5f) {
    radialGradient(fx:50, fy: 50, /*r: 50,*/ fit: true) {
      stop(offset: 0.0f, c: Color.WHITE)
      stop(offset: 0.5f, c: Color.YELLOW)
      stop(offset: 1.0f, c: Color.RED)
      transforms {
        rotate(a: 15, x: 150, y: 150)
      }
    }
  }
}

new SwingBuilder().edt {
  frame(title: "Bouncing Ball", size: [300,300], visible: true) {
    panel(new GfxPanel(), node:node)
  }
}