Is there anyway to run a command if MPC opens a particular media type?

So I can get my projector to switch into 3D mode by issuing a HTTP command, I was wondering is there anyway to get MPC to issue a command when it opens a particular media type. Or create a new media type say .mkv3d that would allow this?

First of all, you need to select MadVR as the video renderer in the options of MPC. That should be able to turn on 3D mode automatically in Windows. Maybe that is already enough for your projector to respond to.

Executing a command is possible too. In MadVR settings, click on "rendering" and then "create profile group". Select "stereo 3d" (or anything else, doesn't matter). As you can see the profile has a command line option. Create two profiles, on for 3d and one for 2d.

In the profile group use this for "profile auto select rules":

Code:

if (3d) "profile_3d"
else "profile_2d"