Previously, with no level loaded in the main editor, and no assets loaded
in the EMotionFX editor, the AnimGraph viewport would only update at 15fps,
even on a 64 core machine.
Digging into this with Pix, I found that EMotionFX's UI would only get
updated for every other call to the ComponentApplication tick.
The Editor's QApplication instance controls how the
`ComponentApplication::OnTick` method is called. This is done in the
`maybeProcessIdle()` method. Generally, I found callstacks like this:
```
EditorQtApplication::maybeProcessIdle()
CCryEditApp::OnIdle()
CCryEditApp::IdleProcessing()
CGameEngine::Update() # ~2.2ms
PhysX::Update() # ~1.8ms
EMotionFX::Update() # ~0.2ms
calls QWidget::update() on all the widgets that change per
frame, only puts update events on the event queue, doesn't
paint anything
AZ::ComponentApplication::TickSystem() # ~25ms
renders the frame with Atom # ~24ms
```
The `maybeProcessIdle()` method is invoked by a QTimer, with a timeout
that changes depending on the application state. If the Editor is in
game mode, it used a timeout of 0, which essentially forced the game to
run at as high an fps as possible. If the Editor application has focus,
it used a timeout of 1ms, asking for the idle processing to happen at
1000 fps. Otherwise, it used a timeout of 10ms, asking for idle
processing at 100 fps.
Those fps targets are not realistic. What happened in this case is that
while the PhysX system was being updated, while the previous
`maybeProcessIdle()` call was still processing, the idle processing
timer would timeout again, and place a timer event on Qt's event queue,
before anything else had a chance to do anything. Only afterward would
EMotionFX's MainWindow::OnTick would be invoked, placing paint events on
Qt's event queue.
The fix for this is to use a single shot timer at the end of each
`maybeProcessIdle()` call. This ensures that any events that are
enqueued during the `maybeProcessIdle()` call are processed prior to the
next call to `maybeProcessIdle()`.
Signed-off-by: Chris Burel <burelc@amazon.com>
* Final update copyright headers to reference license files at the repo root
Signed-off-by: spham <spham@amazon.com>
* Fix copyright validator unit tests to support the stale O3DE header scenario
Signed-off-by: spham <spham@amazon.com>
Chris Burel
Chris Galvan
Yaakuro
Guthrie Adams
Steve Pham
Dayo Lawal
Esteban Papp