Processors have Delay built in for all channels. Some set the distance automatically in the Room Calibration/Correction Software, but I have found those to not be accurate and generally works better to manually set the Delays.
This PDF may help guide you in your venture for placement:
https://www.dolby.com/siteassets/technologies/dolby-atmos/atmos-installation-guidelines-121318_r3.1.pdf
This PDF may help guide you in your venture for placement:
https://www.dolby.com/siteassets/technologies/dolby-atmos/atmos-installation-guidelines-121318_r3.1.pdf