The use of line and form in this painting guides your eyes directly to the center of the piece, which happens to be Jesus Christ, making this a closed composition with a linear perspective. The uses of triangles in this painting lead you to concentrate on key points in the painting. The disciples are in groups of three, with Judas being recognized as the fourth disciple from the left grasping a bag (possibly with silver, as the story suggests). Jesus Christ himself is in a pose that resembles a triangle. A rhythm is used here with the repetition of triangles. I can't really tell much about da Vinci's use of chiaroscuro because of the amount of punishment and restoration that this painting has received over the years. What can be told is that da Vinci probably placed the head of Judas in a shadowy area for a good reason.
Leonardo da Vinci's The Last Supper has been hailed as the greatest example of one point perspective ever