P3D background refresh issue

if it persists on a specific computer try update graphic card driver?
and check again.

some info might see by adding

void mysysinfo() {
  println( "System     : " + System.getProperty("os.name") + "  " + System.getProperty("os.version") + "  " + System.getProperty("os.arch") );
  println( "JAVA       : " + System.getProperty("java.home")  + " rev: " +javaVersionName);
  //println( "\n" + isGL() + "\n" );
  println("OPENGL_VENDOR: " + PGraphicsOpenGL.OPENGL_VENDOR+" OPENGL_RENDERER: " + PGraphicsOpenGL.OPENGL_RENDERER+" OPENGL_VERSION: " + PGraphicsOpenGL.OPENGL_VERSION+" GLSL_VERSION: " + PGraphicsOpenGL.GLSL_VERSION);
  println( "user.home  : " + System.getProperty("user.home") );
  println( "user.dir   : " + System.getProperty("user.dir") );
  println( "sketchPath : " + sketchPath() );
  println( "dataPath   : " + dataPath("") );
  println( "dataFile   : " + dataFile("") );
}

void keyPressed() {
  if ( key == 'i' ) mysysinfo();
}