站长说的很对,补充一下: )o</gt )
Normal Vector cEjdImAzU
The Normal Vector is a vector in 3D space that is used to orient the projection p-r%MnT
plane for the irradiance map. The plane is defined to be perpendicular to the PB67?d~
Normal Vector, and the irradiance incident on the selected surface is projected g
Pj0H&,.
onto this plane. When the map is displayed, the normal vector is pointing toward #
pB:LPEsK
you.
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Up Vector 1 "7#|=1/
The Up Vector is a vector in 3D space that is used to orient the projection plane v@uaf=x-
for the irradiance map. The plane is defined so that the Up Vector is parallel to the qg{<&V7fE
vertical side of the plane. The irradiance incident on the selected surface is Sw@,<4S
projected onto this plane. When the map is displayed, the up vector will point H8]^f=
toward the top of the screen.