站长说的很对,补充一下: ,G?WAOy,
Normal Vector YWO)HsjP
The Normal Vector is a vector in 3D space that is used to orient the projection
B Qxs~
plane for the irradiance map. The plane is defined to be perpendicular to the Zaf:fsj>
Normal Vector, and the irradiance incident on the selected surface is projected ~[nSXnPO
onto this plane. When the map is displayed, the normal vector is pointing toward ?ri?GmI|
you. LxSpctiNx
Up Vector 9ZsVy
The Up Vector is a vector in 3D space that is used to orient the projection plane ,K"U>&
for the irradiance map. The plane is defined so that the Up Vector is parallel to the W/bQd)Jvk
vertical side of the plane. The irradiance incident on the selected surface is :zke %Yx
projected onto this plane. When the map is displayed, the up vector will point 4-y:/8
toward the top of the screen.