Buddha Shakyamuni and two Bodhisattvas:                 Maitreya and Manjushri

In the very center of the painting it glorifies the image of Shakyamuni and two great bodhisattvas Maitreya and Manjushri.

"Shakyamuni is the Buddha of our historical period. To understand the omnipresence of his icon in Tibetan culture, we must understand what "Buddha" (T. sangs-rgyas) means to the believers. A Buddha is a being -both human and divine, either male or female-who has "awakened" (sangs) from the sleep of ignorance and has purified all evil, a being who has "expanded" (rgyas) limitlessly the power of his or her compassion and accomplished all goodness. A Buddha is a form of life that has achieved the highest evolutionary perfection possible. He or she is perfect wisdom (the experience of the exact nature of reality) and perfect compassion (the embodiment of the will to others' happiness). Buddhahood transcends suffering and death and incorporates the perfected abilities to experience and communicate happiness to all living beings.

from "Wisdom and Compassion"  the Sacred art of Tibet