站长说的很对,补充一下: D 77$aCt
Normal Vector of'H]IZ
The Normal Vector is a vector in 3D space that is used to orient the projection N_p^DP
plane for the irradiance map. The plane is defined to be perpendicular to the Gw#z:gX2
Normal Vector, and the irradiance incident on the selected surface is projected S-79uo
onto this plane. When the map is displayed, the normal vector is pointing toward Pa{bkr
you. aW#^@||B
Up Vector {~V_6wY g
The Up Vector is a vector in 3D space that is used to orient the projection plane PI)uBA;
for the irradiance map. The plane is defined so that the Up Vector is parallel to the C9j5Pd5q1L
vertical side of the plane. The irradiance incident on the selected surface is \,G19o}`Es
projected onto this plane. When the map is displayed, the up vector will point +WvW#wpH
toward the top of the screen.