I have reviewed each change carefully, but it is a large change and I could have missed something! Here is a summary of the types of changes in this CL:
* Made nullptr checks consistent (the plurality of the changes are of this type)
* Completed switch statements (IE, switch did not explicitly handle default case, but had unhandled enum entries - this is the second most popular type of fix)
* Removed unused variables
* Removed redundant initializations
* WidgetNavigationCustomization.cpp was fixed by the owner
* integers converted to floats where result was stored in a float
* Removed redundent null checks (e.g. before delete statements)
* Renamed variables to prevent non-obvious shadowing
* Fixed use of bitwise & when checking for equality to an enum entry (which is often 0)
* Fixes for some copy paste errors (e.g. FoliageEdMode.cpp)
[CL 2498053 by Dan Oconnor in Main branch]
- The entire editor can now be compiled using Clang on Windows. It also runs (as long as you use the MSVC linker.)
- Use UEBuildWindows.bCompileWithClang=true to help test Clang support
- Most UE4 programs can now be compiled using Clang on Windows, and linked using the Clang linker on Windows
- Many C++ syntax fixes to resolve Clang errors and warnings when on Windows
- Clang on Windows now supports PCH files properly (but not "shared" PCHs, yet.)
- Hacked the DirectX XAudio2 headers slightly to work around a macro pasting bug in Clang
[CL 2494439 by Mike Fricker in Main branch]
* Multicast delegate Add* calls now return FDelegateHandles, and Remove* calls are now all deprecated, except for a new Remove function which takes a FDelegateHandle.
* New FConsoleManager::RegisterConsoleVariableSink_Handle and UnregisterConsoleVariableSink_Handle functions which work in terms of FConsoleVariableSinkHandle.
* Timer calls which don't take FTimerHandles are deprecated.
* FTicker::AddTicker now returns an FDelegateHandle and is removed by an overloaded Remove function.
* DEFINE_ONLINE_DELEGATE* macros now define _Handle variants of the Add/Remove functions which return/take handles.
* Various other handle-based registration changes.
* Some unity build fixes.
* Some simplification of delegate code.
* Fixes for lots of existing code to use handle-based registration and unregistration.
#codereview robert.manuszewski
[CL 2400883 by Steve Robb in Main branch]
UETOOL-213 - Minimize Slate FString -> FText conversion (remove SLATE_TEXT_ATTRIBUTE)
This fixes any editor/engine specific code that was passing text to Slate as FString rather than FText.
[CL 2399803 by Jamie Dale in Main branch]
Introduces the concept of "Active Ticking" to allow Slate to go to sleep when there is no need to update the UI.
While asleep, Slate will skip the Tick & Paint pass for that frame entirely.
- There are TWO ways to "wake" Slate and cause a Tick/Paint pass:
1. Provide some sort of input (mouse movement, clicks, and key presses). Slate will always tick when the user is active.
- Therefore, if the logic in a given widget's Tick is only relevant in response to user action, there is no need to register an active tick.
2. Register an Active Tick. Currently this is an all-or-nothing situation, so if a single active tick needs to execute, all of Slate will be ticked.
- The purpose of an Active Tick is to allow a widget to "drive" Slate and guarantee a Tick/Paint pass in the absence of any user action.
- Examples include animation, async operations that update periodically, progress updates, loading bars, etc.
- An empty active tick is registered for viewports when they are real-time, so game project widgets are unaffected by this change and should continue to work as before.
- An Active Tick is registered by creating an FWidgetActiveTickDelegate and passing it to SWidget::RegisterActiveTick()
- There are THREE ways to unregister an active tick:
1. Return EActiveTickReturnType::StopTicking from the active tick function
2. Pass the FActiveTickHandle returned by RegisterActiveTick() to SWidget::UnregisterActiveTick()
3. Destroy the widget responsible for the active tick
- Sleeping is currently disabled, can be enabled with Slate.AllowSlateToSleep cvar
- There is currently a little buffer time during which Slate continues to tick following any input. Long-term, this is planned to be removed.
- The duration of the buffer can be adjusted using Slate.SleepBufferPostInput cvar (defaults to 1.0f)
- The FCurveSequence API has been updated to work with the active tick system
- Playing a curve sequence now requires that you pass the widget being animated by the sequence
- The active tick will automatically be registered on behalf of the widget and unregister when the sequence is complete
- GetLerpLooping() has been removed. Instead, pass true as the second param to Play() to indicate that the animation will loop. This causes the active tick to be registered indefinitely until paused or jumped to the start/end.
[CL 2391669 by Dan Hertzka in Main branch]
