Tomas Slancik

vinay472341
I have a alembic car animation

if your car in alembic has animated transform ( is not just deforming geo ) you can use Alembic Xform Object to extract that transform from your alembic file directly and parent camera to it

this is likely an oversight on MPM Source
since setting Emission Type to Once also freezes the animation that's then being sampled internally
so if you want to avoid unlocking the MPM Source or transferring animation yourself afterwards you can do:

- set Emission Type to: Continuous
- set Activation to: $FF==detail("CONTAINER", "startframe", 0)

olivierth
I tried to replicate all settings but my buttons don't show up. The only difference I found is the "Use Menu" (under the Menu tab).

yes, that's one gotcha of Button Strip, it has to have the menu enabled and then the buttons in Button Strip are the entries in the menu
and the menu type defines whether you can select only a single option (Replace) or allowed to select multiple ( Toggle )

since menu is compulsory the menu checkbox is grayed out, but there seems to be a bug that the parameter still cares whether the checkbox is enabled or not

if you create Button Strip parm directly then the menu will be enabled
however if you created parameter of any other type and then changed it to Button Strip (which is likely what happened) then the menu is likely unchecked

so just change it to Int, enable Menu and change back to Button Strip
or create Button Strip to begin with