Update 18 of the Houdini Engine for Unreal Plugin.

The plugin is now linked to Houdini 19.5.640 / HAPI 5.0.7.

Source and binaries are included for:
UE4.27, UE5.1, and UE5.2 on Windows. and Mac OS.

Changes:

• Added support for Unreal Engine 5.2

• Various updates to the source code and includes to fix compile issues when building the plugin with no-pch/non-unity builds of UE5.2.

• Added the ability to set a custom $HOME directory in the plugin settings.
  It is then used by HAPI, but also Houdini/Session Sync when using the "Open In" commands.
  This is helpful when having HE under source control, as it allows custom nodes to be detected properly.

• Tags can now be modified via generic attributes on any type of actors, not just Landscapes.
  When modifying tags on actors, it is possible to modify the component tags by naming the attribute "unreal_uproperty_ComponentTagsXXXX".

• Inputs now have a "rebuild" button next to the input type combobox, that allows you to force update/resend the input's objects.

• Handles now display their name and type on the editor viewport.

• Added support for Data Layers in Unreal 5.2 and later.

• Added support for Material instances in landscapes.

• Improved removal of existing foliage when baking. Only the instances baked by Houdini will be removed.

• Fixed wrong transform being set for landscapes when using the old input system.

• Fixed an issue where cooked landscapes would be deleted correctly.

• Update Landscape imported in Unreal to work better with World Partitioned Levels.
  Support for World Composition removed in Unreal 5 versions of the plugin.

• Stopped foliage removal dirtying all Instanced Foliage Actors in a scene

• Fixed an issue World Partition Landscapes would be offset if partially loaded in Unreal.

• Fixed incorrect material assignment when using instancers.

• It is now possible to use/mix both material override attributes (unreal_materialX)
  and material instance attributes (unreal_material_instanceX) with instancers.

• Fixed Houdini Asset Component properites not serializing correctly.

• Fixed bug that caused incorrect vertex colors/alpha on imported Static Meshes.

• Fixed bug that caused incorrect vertex colors overrides on Static Mesh Components.

• Fixed an issue that caused mesh socket scale to be ignored when attachingActors.
  We now force the relative scale of the attached Actors to the scaledefined on the sockets.

• Fixed potential crash with Toggle parameters and the PDG asset link.

• Fixed an issue when importing BP as reference:
  We were only importing the BP's component as reference, not the BP itself.

• Ported attribute transfer optimizations from Unreal 5.0 to Unreal 4.26 & 4.27

• Fixed default object path parameters on OBJ HDA (lookatpath, lookupobjpath..) arent incorrectly considered as inputs anymore.

• Fixed crash when using the new input system with UE5.2.

• Fixed incorrect drawing of tabs parameters in UE5.

• Fixed unnecessary error logs with input and parameter detail, physical materials.

• Fixed unnecessary invalid session error logs when fetching license type beforestarting the session.

• Fixed issues that caused transform handles to not handle rotations properly.

• Fixed an issue that caused incorrect values being used when manually enteringscale/rotation for handles in the details panel.

• Fixed generated material instances not always being properly baked for instancers.

• Removed the "Update Input Landscape" feature as it was non longer needed/used.
  Please use Landscape Edit Layers instead.

• Fixed a regression that caused a crash when using geometry inputs.