The main problem with giving tyMesher native motion blur support, is that it has to happen at a baseObject level...so as soon as you add modifiers on top (a very common thing to do with tyMeshers), all my hard work to get moblur working will go out the window because renderers query the evaluated (collapsed) object, not the baseObject. So I really see no point in putting in the effort to add it directly.
Really it's the renderers that need to all support a common Mesh velocity channel to store moblur vectors, which would survive the stack. 3dsmax 2020 implemented a channel like that, but I don't know how many renderers have adopted it yet.
However, there is a workaround currently that will allow you to get moblur on tyMesher blobmeshes. It's somewhat annoying to do but it should give you the result you want.
1) In your source tyFlow, use a Custom Properties operator to store your particle velocity to a custom data channel (in continuous mode).
2) Use a Mapping operator in continuous mode to save that channel data to map channel 20.
3) Create your tyMesher blobmesh (enable "inherit UVWs")...then add whatever modifiers you want, etc.
4) Create a new empty tyFlow.
4) Add an Export Particles operator to the empty flow and add the tyMesher to the additional geometry rollout, then cache it.
5) Render that cache with VRay.
tyCache and tyFlow send VRay deformation blur data through map channel 20, so by baking it into your blobmesh and rendering a cache of it, you can send the data to VRay. Alternatively you could assign those velocity vectors to any map channel you like, render a pass with Vertex Colors enabled, and then use that pass to add the blur in post.
The next build has a "mapping from velocity" setting in the Mapping operator, so you can skip the Custom Properties step.
Really it's the renderers that need to all support a common Mesh velocity channel to store moblur vectors, which would survive the stack. 3dsmax 2020 implemented a channel like that, but I don't know how many renderers have adopted it yet.
However, there is a workaround currently that will allow you to get moblur on tyMesher blobmeshes. It's somewhat annoying to do but it should give you the result you want.
1) In your source tyFlow, use a Custom Properties operator to store your particle velocity to a custom data channel (in continuous mode).
2) Use a Mapping operator in continuous mode to save that channel data to map channel 20.
3) Create your tyMesher blobmesh (enable "inherit UVWs")...then add whatever modifiers you want, etc.
4) Create a new empty tyFlow.
4) Add an Export Particles operator to the empty flow and add the tyMesher to the additional geometry rollout, then cache it.
5) Render that cache with VRay.
tyCache and tyFlow send VRay deformation blur data through map channel 20, so by baking it into your blobmesh and rendering a cache of it, you can send the data to VRay. Alternatively you could assign those velocity vectors to any map channel you like, render a pass with Vertex Colors enabled, and then use that pass to add the blur in post.
The next build has a "mapping from velocity" setting in the Mapping operator, so you can skip the Custom Properties step.