Being a recent "switcher" from being stereotypical PC user, when I started using my MacBook Pro in recent months I found some things missing in OSX that I was used to in Window's laptops ... one thing being a presentation power mode so that the MacBook Pro screen wouldn't dim and black out without any mouse activity. To be honest I wasn't using it for doing presentations, but I was watching a show on
Hulu. It was irritating when the screen would keep on blacking out during an exciting scene.
Finally I figured out how to set the MBP to have a "presentation" power mode. In System Preferences, click on "Energy Saver". When set to settings for "Battery", set Optimization to "Custom". Set sleep options to an hour or never. Under Options uncheck "slightly dim the display when using this power source". Also uncheck the next option, too, for auto reducing brightness.
Then the next time you want to watch Hulu or actually do a presentation, click on the battery icon in the upper right hand corner of the screen and set the Power Mode to "Custom".
Perhaps there was an easier way to set an MBP to presentation power mode. But I never found it. This worked for me.