As part of an application I have created and am in the process of seeing if I can implement the code that I have created as an Unreal PCG plugin, a major part of that application is the ability to utilise HLSL compute shader code to modify or assign values to a value attribute of a one dimensional hexagonal close packed (HCP) grid.
Observing that there are many similarities in what I have done in my virtual worlds application to the Unreal Engine PCG plugin (very similar in fact), I took the chance that there is a HLSL editor and compiler ability somewhere in the PCG plugin and did a search on google and found this tutorial “Unreal Engine 5.5-Compute Shaders with PCG introduction.”
for UE 5.5 of which I have a copy but never used.
What I found was that this custom HLSL node exists in Unreal engine 5.7.1, but that the ability to enter and edit hlsl code and compile it so as to modify point attribute data as in this tutorial is not available. Since I am writing a PCG plugin and have successfully created a couple of PCG nodes integrating my code into it, I took the liberty to follow the trail of this custom HLSL PCG node and found that the problem seems to be that the code to edit/compile HLSL is disabled because of a
#if WITH_EDITORONLY_DATA
plugin UPROPERTY definitions
#endif
What ! This is not present in the UE 5.5 code that I then had a look at
Tracing backwards I found that there is this pre compile code in a CoreMiscDefines.h file
#ifndef WITH_EDITORONLY_DATA
#if !PLATFORM_CAN_SUPPORT_EDITORONLY_DATA || UE_SERVER || PLATFORM_IOS
#define WITH_EDITORONLY_DATA 0
#else
#define WITH_EDITORONLY_DATA 1
#endif
#endif
of which there further exits in a WindowsPlatform.h file
#define PLATFORM_CAN_SUPPORT_EDITORONLY_DATA 1
which disables the ability to create hlsl compute shader code and compile it on a windows platform.
My question is why is this the case?
Is there some development of these custom hlsl compute shader nodes that is in the works for a future release, or are there major bugs that need fixing?
Or is this disabled as a coding error that can be remedied by a simple assignment of
#define PLATFORM_CAN_SUPPORT_EDITORONLY_DATA 0
and recompiling the Unreal Engine?
Or is there an editor or other setting within the UE that needs to be initialised to be able to use this custom HLSL node to create and compile hlsl in a compute shader ?
For me, this is a core feature of the application I have developed and to have it in the PCG Unreal Engine plugin as was demonstrated in the tutorial above is a must have feature.
To have this information before I get the temptation to start duplicating and editing this custom hlsl pcg node would be advantageous. No good to use this node if there are existing problems that need to be addressed.
Thanks and appreciate in advance for any answers that can be provided.