MRTK3 Errors On MRTK2 to MRTK3 Migration

Question

I have been migrating my repo from MRTK2 to MRTK3 and some of the steps have not been clear. Are the MRTK 2.8.3 packages necessary for MRTK3 to work?

My process has been as follows:

• delete previous MRTK 2.8.3 packages from the package manager
• import MRTK3 packages from the Mixed Reality Feature Tool
• open Unity

if I open Unity and don't bring in the dependencies when Unity asks, then I get a ton of errors from missing references from MRTK2 (see image below), but if I do bring in the dependencies I get errors of overlap scripts between MRTK2 and MRTK3 like for the NonNativeKeyboard.

I can't find any documentation on this from MSFT, can anyone help?

Answer 1

Please note a key point is that MRTK3 is not a drop-in replacement for MRTK2.

The '3' in MRTK3 is not a version number. It's an indicator of the generation of the underlying architecture, with HoloToolkit being generation one and MRTK v2.x being generation two.

The architecture of MRTK3 is different from MRTK2. There isn't a 1:1 class mapping from MRTK2 to MRTK3, so errors are expected where you reference MRTK2 classes that aren't in MRTK3. For more details, please see MRTK3 documentation.

The next step after "open Unity" is to go through and address the errors. There is a concept mapping to help identify replacement features at Migration guide from MRTK2 to MRTK3.