code: public function toOptionArray() {
          $options = array();
          $options[] = array(
              'value'=> 'aoe_templatehints/renderer_comment',
              'label'=> Mage::helper('aoe_templatehints')->__('Comments')
          );
          $options[] = array(
              'value'=> 'aoe_templatehints/renderer_opentip',
              'label'=> Mage::helper('aoe_templatehints')->__('Popups')
          );
          $options[] = array(
              'value'=> 'aoe_templatehints/renderer_tipOnly',
              'label'=> Mage::helper('aoe_templatehints')->__('Popups (border initially invisible)')
          );
  
          Mage::dispatchEvent('aoetemplatehints_hintrenderer_options', array('options' => &$options));
  
          return $options;
      }
docs: Get option array
  
  @return array