Using hot reload with CoherentUIGT installed as a game plugin

Hot reload via the IDE is only possible with CoherentUIGT installed as an engine plugin. Attempts to use hot reload via the IDE (e.g. Visual Studio on Windows) with CoherentUIGT installed as a game plugin will fail due to a known bug in UE4 where it tries to hot reload game plugins even though they haven't been modified. Epic are aware of the issue but haven't given any estimates on when a fix can be expected. As an alternative, you can use hot reload via the Unreal Editor when using CoherentUIGT as a game plugin.

UE4 on Mac

UE4 is crashing on Mac version 10.12 (Sierra) or lower with integrated video card due to driver bug. Possible solution is to upgrade to newer version of Mac, for example 10.13 (High Sierra).

Missing input for in-world views using Vulkan rendering

Input for in-world views requires getting the mesh data from the GPU, but the Vulkan API does not support this yet, so instead the plugin have to access the CPU data if it is available.

To have a working input for in-world views using Vulkan, "Allow CPU Access" option should be enabled in the static mesh settings of the meshes, used for the in-world views.

Asserting input for in-world views using DirectX12 rendering in UE4.23

Input for in-world views requires getting the mesh data from the GPU, but after UE4.23.0 users can hit assert in FD3D12DynamicRHI::LockBuffer using DirectX12.

The issue has already been reported to Epic Games. The fix is expected to be present in the UE4.23.1 release.

This issue can be resolved by reverting the if statement inside the FD3D12ResourceLocation::AsStandAlone function as it was in UE4.22.3.