Does "painting with books" mean adding poetry to painting or using calligraphy skills in painting?

Personally, it is mainly about the skills of calligraphy in painting creation. Modern celebrities include Zheng Banqiao and Wu Changshuo. The former uses the brushwork of official script to draw bamboo, while the latter uses the method of writing stone drums to draw branches. Great painters used to write well, but now this tradition has been lost.