def check_valid(self):
if self.color is None and self.texture is None:
xmlr.on_error("Material has neither a color nor texture.")
def check_valid(self):
if self.color is None and self.texture is None:
xmlr.on_error("Material has neither a color nor texture")
def check_valid(self):
if self.color is None and self.texture is None and not Material.error_already_displayed:
Material.error_already_displayed = True
xmlr.on_error("Material has neither a color nor texture\n")