def imprime(self):
        printer = QPrinter(QPrinter.HighResolution)
        printer.setPageSize(QPrinter.A4)
        printer.setColorMode(QPrinter.Color)
        printer.setCreator("Dieu")
        printer.setDocName("ma belle image")
        printer.setOutputFileName("image.pdf")

        dialog = QPrintDialog(printer, self)
        ret = dialog.exec_()
        if ret != QDialog.Accepted:
            return

        painter = QPainter()
        self.export_to_pages(painter, printer)

    def export_to_pages(self, painter, printer):
        """ export_to_pages: export the scene on painter with a number of pages
        """
        w = printer.pageRect().width()
        h = printer.pageRect().height()
        numPage = int(round(self.ui.vue.scene.height() / h))
        painter.begin(printer)
        for page in range(0, numPage):
            self.ui.vue.scene.render(painter, QRectF(0, 0, w, h), QRectF(0, h * page, w, h))
            if page < numPage-1:
               printer.newPage()
        painter.end()