Abstract: This disclosure provides a method for generating an optimal tree for rendering or streaming a 3D model. The method includes: obtaining a complete tree of a 3D model; obtaining a quality value of a node of the complete tree of the 3D model; obtaining a visibility value of the node of the complete tree of the 3D model; determining an optimal tree of the 3D model based on the complete tree, the quality value, and the visibility value; and rendering the 3D model based on the optimal tree.

Abstract: Provided is a light emitting device including: a substrate; a light emitting diode chip; and a phosphor layer. The phosphor layer includes a first cover part and a second cover part; the first cover part is disposed on the top surface of the light emitting diode chip, and the second cover part covers the surface of the substrate at the peripheral area of the light emitting diode chip. Further, there is a height difference between the top surface of the second cover part and the top surface of the first cover part; the top surface of the second cover part is at a position lower than that of the top surface of the first cover part.