Yes, attach to custom shader slot. In Maya, we will have a handy script for you to use.
For user_ibl_rect, apply a texture, and the light will be sampled according to the importance of light at each position in the texture. For example, if you like making a card with nice big spot in the rectangle, for product lighting. Or for VFX, if you capture actual rendered detail of complex distant geometry that you want to simplify into card from a certain position.
Training and Special Projects, NVIDIA ARC
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