There was once an artist named Wen Tong, famous for his bamboo paintings. Many people sought his artwork.
People wondered about his skill. Wen Tong loved bamboo deeply and cultivated various kinds around his home. Regardless of season or weather, he would observe the bamboo forest, studying its growth.
He meticulously observed the bamboo poles' dimensions and the leaves' shapes and colors. Whenever he discovered something new, he would return to his study and sketch his mental images. Over time, the images of bamboo in different seasons, weather, and moments became deeply imprinted in his mind.
Whenever he stood before paper with a brush, various forms of bamboo instantly came to him. Thus, he always painted with confidence and ease, and his bamboo looked remarkably lifelike.
When praised, he modestly said he merely transferred the bamboo images from his mind onto paper.
The phrase "having the images of bamboo ready in one's bosom" means having well-prepared plans before undertaking a task to ensure success. It also signifies being calm and composed when handling matters.