站长说的很对,补充一下: S+(-k0
Normal Vector uCNi&.
The Normal Vector is a vector in 3D space that is used to orient the projection VZArdXTP
plane for the irradiance map. The plane is defined to be perpendicular to the m2"~.iM8
Normal Vector, and the irradiance incident on the selected surface is projected 7Z<ba^r}
onto this plane. When the map is displayed, the normal vector is pointing toward kMLWF
you. As7Y4w* +
Up Vector Lk|%2XGO&
The Up Vector is a vector in 3D space that is used to orient the projection plane 5 J9,/M0
for the irradiance map. The plane is defined so that the Up Vector is parallel to the r8E)GBH-|
vertical side of the plane. The irradiance incident on the selected surface is *^&2L,w
projected onto this plane. When the map is displayed, the up vector will point 4U;6 2 jq
toward the top of the screen.