- allows platform extensions to determine whether it is available
#jira UE-204162
#rnx
#rb Chris.Babcock, Devin.Doucette
[CL 31120967 by david harvey in ue5-main branch]
Significant refactor of RHI command list management and submission, and RHI breadcrumbs / RenderGraph (RDG) scopes, to allow for parallel translation of most RHI command lists.
See individual changelists in //UE5/Dev-ParallelRendering for details. A summary of the changes is as follows:
This work's primary goal was to allow as many RHI command lists as possible to be parallel translated, to make more efficient use of many-core systems. To achieve this:
- The submission code paths for the immediate and parallel RHI command lists have been merged into a single function: FRHICommandListExecutor::Submit().
- A "dispatch thread" (which is simply a series of chained task graph tasks) is used to decide which command lists are batched together in a single parallel translate job.
- Individual command lists can disable parallel translate, which forces them to be executed on the RHI thread. This happens automatically if an RHI command list performs an operation that is not thread safe (e.g. buffer lock, or low-level resource transition).
One of the primary blockers for parallel translation was the RHI breadcrumb system, and the way RDG builds scopes. This was also refactored to remove these limitations:
- RDG could only push/pop events on the immediate command list, which resulted in parallel and immediate work being interleaved, breaking any opportunity for parallelism.
- Platform RHI implementations of breadcrumbs (e.g. in D3D12 RHI) was not correct across multiple RHI contexts. Push/pop operations aren't necessarily balanced within any one RHI context given that RDG builds "parallel pass sets" containing arbitrary ranges of renderer passes.
A summary of the new RHI breadcrumb system is as follows:
- A tree of breadcrumb nodes is built by the render thread and RDG. Each node contains the node name, and pointers to the parent and next nodes. When fully built, the nodes form a depth-first linked list which is used for traversing the tree for GPU crash debugging.
- The memory for breadcrumb nodes is provided by ref-counted allocator objects. These allocators are pipelined through the RHI, allowing the platform RHI implementation to extend their lifetime for GPU crash debugging purposes.
- RHIPushEvent / RHIPopEvent have been removed, replaced with RHIBeginBreadcrumbGPU / RHIEndBreadcrumbGPU. Platform RHIs implement these functions to perform GPU immediate writes using the unique ID of each node, for tracking GPU progress.
- Format string arguments are captured by-value to remove the cost of string formatting while building the breadcrumb tree. String formatting only occurs when the actual formatted string is required (e.g. during GPU crash breadcrumb stack traversal, or when calling platform GPU profiling APIs).
RenderGraph scopes have been simplified:
- The separate scope trees / arrays of ops have been combined. There is now a single tree of RDG scopes containing all types.
- Each RDG pass holds a pointer to the scope it was created under.
- BeginCPU / EndCPU is called on each RDG scope as the various RDG threads enter / exit them. This allows us to mark-up each worker thread with the relevant Unreal Insights scopes.
Other changes include:
- Fixes for bugs uncovered when parallel translate was enabled.
- Adjusted platform affinities necessary due to the new layout of thread tasks in the renderer.
- Refactored RHI draw call stats to better fit the new pipeline design.
#rb jeannoe.morissette, zach.bethel
#jira UE-139543
[CL 30973133 by Luke Thatcher in ue5-main branch]
Deprecated CONSTEXPR, PLATFORM_COMPILER_HAS_DECLTYPE_AUTO, PLATFORM_COMPILER_HAS_FOLD_EXPRESSIONS and UE_NORETURN.
Made UE_NODISCARD mandatory (not yet deprecated as fixup is needed).
#rb devin.doucette
[CL 30617451 by steve robb in ue5-main branch]
[FYI] keaton.stewart
Original CL Desc
-----------------------------------------------------------------
[Backout] - CL26221679 [Main CIS Issue] Errors in Incremental FortniteServer Linux and Incremental Compile Monolithics - Linux
[FYI] Josh.Adams
Original CL Desc
-----------------------------------------------------------------
- Very super early support for VisionOS (requires Xcode 15 beta2 or later).
- THIS IS NOT USABLE YET - WORK IN PROGRESS!
- It builds, links with IOS libs (warnings, not errors), can cook and it boots in Simulator, but is dying in MetalRHI
- UnrealTargetPlatform.VisionOS is currently defined in Engine code, it is not pulled out like would be correct for a full true platform extension
- Refactored a lot of Build.cs files to use UnrealPlatformGroup.IOS/Apple instead of individual platform checks, to make VisionOS integration simpler
#rb zack.neyland
[CL 26226852 by josh adams in ue5-main branch]
#fyi Josh.Adams
#jira FORT-626566 (edited)
Original CL Desc
-----------------------------------------------------------------
- Very super early support for VisionOS (requires Xcode 15 beta2 or later).
- THIS IS NOT USABLE YET - WORK IN PROGRESS!
- It builds, links with IOS libs (warnings, not errors), can cook and it boots in Simulator, but is dying in MetalRHI
- UnrealTargetPlatform.VisionOS is currently defined in Engine code, it is not pulled out like would be correct for a full true platform extension
- Refactored a lot of Build.cs files to use UnrealPlatformGroup.IOS/Apple instead of individual platform checks, to make VisionOS integration simpler
#rb zack.neyland
[CL 26223564 by keaton stewart in ue5-main branch]
- THIS IS NOT USABLE YET - WORK IN PROGRESS!
- It builds, links with IOS libs (warnings, not errors), can cook and it boots in Simulator, but is dying in MetalRHI
- UnrealTargetPlatform.VisionOS is currently defined in Engine code, it is not pulled out like would be correct for a full true platform extension
- Refactored a lot of Build.cs files to use UnrealPlatformGroup.IOS/Apple instead of individual platform checks, to make VisionOS integration simpler
#rb zack.neyland
[CL 26221679 by Josh Adams in ue5-main branch]
This is because currently QueueAsyncCommandListSubmit() only supports command lists with their own local contexts for parallel translation. When parallel translation is not used, these commands need to be replayed on the immediate context, but bypass mode would create a local context and translate commands into it, and this context is never finalized and submitted.
Also removed PLATFORM_RHITHREAD_DEFAULT_BYPASS, since bypass should be off by default on all platforms. Using this assumption, the Bypass() methods return compile-time constants in test and shipping builds, so all the bypass code can be compiled out.
#jira UE-185658
#rnx
#rb Luke.Thatcher
[CL 26052694 by mihnea balta in ue5-main branch]
- Marked RHI modules with an [RHIModule] C# attribute, so UBT can determine how many RHIs are being included in the build via standard module references.
- Refactored the "fixed RHI class" macros to automatically de-virtualize RHI command calls. WITH_FIXED_RHI_CLASS is always defined to 1 if there's only a single RHI module included in the build.
Unified "-rhivalidation" command line switch handling.
#rb mihnea.balta
#preflight 64247bb8c42c7fd1cb5fc582
[CL 24869066 by Luke Thatcher in ue5-main branch]
Add the argument to many but not all callsites.
#jira FORT-578919
#rnx
#rb Devin.Doucette
#preflight 6414ca9d691c5ebc15b30410
[CL 24696053 by Matt Peters in ue5-main branch]
- Implemented logic for setting allowed screen orientations on iOS.
- Added possibility to set allowed screen orientation to SCREEN_ORIENTATION_SENSOR on Android so that the screen orientation can be unlocked to adjust itself according to the sensor.
- Exposed PortraitSensor, LandscapeSensor and FullSensor screen orientations in blueprint library.
#RB Chris.Babcock Adam.Kinge
#ROBOMERGE-AUTHOR: bernard.lambert
#ROBOMERGE-SOURCE: CL 21219114 via CL 21219129 via CL 21219137 via CL 21219139 via CL 21219150
#ROBOMERGE-BOT: UE5 (Release-Engine-Staging -> Main) (v972-20964824)
[CL 21224334 by bernard lambert in ue5-main branch]
[FYI] bernard.lambert
Original CL Desc
-----------------------------------------------------------------
- Added functions to get and set allowed screen orientations through the PlatformMisc class.
- Implemented logic for setting allowed screen orientations on iOS.
- Added possibility to set allowed screen orientation to SCREEN_ORIENTATION_SENSOR on Android so that the screen orientation can be unlocked to adjust itself according to the sensor.
- Exposed PortraitSensor, LandscapeSensor and FullSensor screen orientations in blueprint library.
#ROBOMERGE-AUTHOR: nat.parkinson
#ROBOMERGE-SOURCE: CL 21197038 via CL 21197050 via CL 21197054 via CL 21197064 via CL 21197075
#ROBOMERGE-BOT: UE5 (Release-Engine-Staging -> Main) (v972-20964824)
[CL 21197499 by nat parkinson in ue5-main branch]
- Implemented logic for setting allowed screen orientations on iOS.
- Added possibility to set allowed screen orientation to SCREEN_ORIENTATION_SENSOR on Android so that the screen orientation can be unlocked to adjust itself according to the sensor.
- Exposed PortraitSensor, LandscapeSensor and FullSensor screen orientations in blueprint library.
#ROBOMERGE-AUTHOR: bernard.lambert
#ROBOMERGE-SOURCE: CL 21196825 via CL 21196834 via CL 21196849 via CL 21196861 via CL 21196876
#ROBOMERGE-BOT: UE5 (Release-Engine-Staging -> Main) (v972-20964824)
[CL 21197495 by bernard lambert in ue5-main branch]
