Premiere Pro + AE Plugin SDK: Premiere doesn't support PF_WindowUnion->PF_ItemWindowInfo->port_rect

Premiere Pro doesn't support the same layout for the PF_EventExtra structure when invoking plugins based on the AE SDK to handle events in teh Layer or Comp windows.

In After Effects, by virtue of uncommenting a macro in the SDK headers, plugins can access the context-specific PF_WindowUnion when processing events for the Layer and Comp windows. Crucially, this gives a plugin access to the PF_ItemWindowInfo->portRect member, the only sanctioned method to know the current viewport coordinates.

In Premiere Pro, if a plugin attempts to access that same structure, it is clearly filled with the wrong information, suggesting that the PF_USE_NEW_WINDOW_UNION is indeed After Effects-only.

Lacking this vital piece of information, plugins in Premiere Pro are forced to use a rather unorthodox approach. When handling a draw event, the PF_DrawEventInfo->update_rect member appears to containt coordinates for the viewport, which need to be cached and reused when processing mouse input. This is not ideal since it requires sharing state between drawing and event processing. It relies on the assumption that the update_rect is indeed always set to the entire viewport, something that isn't mentioned or guaranteed by the SDK. Lastly, it creates yet another situation where plugins have to be coded very different for two apps that presumptively share the same SDK.

Expected results:

Make Premiere Pro support the same PF_ItemWindowInfo structure. Get rid of that PF_USE_NEW_WINDOW_UNION macro that magically unlocks this SDK feature just in AE. Instead, document which version of your apps support it, specifically what version of Premiere Pro will begin supporting the same union to give plugins clean access to the current viewport.