LGUI Stat
LGUI provide some stat info for quike performance check: Stat->Advanced->LGUI and Stat->Advanced->LTween:
When it is on, the stat info will show:
There are 4 main items that you should check first, they contains almost all LGUI's cost: Hud RHIRender， Canvas Update, EventSystem, UpdateLayoutInterface.
All cost of LGUI Renderer in render thread, contains render mode of ScreenSpaceOverlay and WorldSpace-LGUIRenderer. Not contains WorldSpace-UERenderer, because in WorldSpace-UERenderer mode, LGUI just generate render data (mesh, material) and leave them for UE to render it as normal scene object.
PostProcess_BackgroundBlur
Render cost of UIBackgroundBlur component.
PostProcess_BackgroundPixelate
Render cost of UIBackgroundPixelate component.
LGUIMesh CreateSceneProxy
This happens when LGUIMeshComponent is creating SceneProxy.
LGUIMesh CreateMeshSection
This happens when LGUIMeshComponent's SceneProxy is creating mesh section, means LGUI is rebuilding drawcall.
All cost of LGUI Renderer in game thread, no matter what render mode it is. In game thread, LGUI generate mesh & texture atlas & material & other render resource.
Canvas BatachDrawcall
LGUICanvas do sort depth, calculate overlap, and batch drawcall.
UIGeometry TransformVertices
LGUI will collect all created geometry, and transform it's vertices & normals & tangents from UI element's local space to LGUICanvas's local space.
UIBatchGeometryRenderable GeometryModifier
GeometryModifier (UIEffectXXX, include TextAnimation) update render geometry in game thread.
UIPostProcessRenderable UpdateGeometry
UIPostProcessRenderable (UIBackgroundBlur & UIBackgroundPixelate) update render geometry in game thread.
Update all layout object which inherit interface ILGUILayoutInterface, such as UIHorizontalLayout, UIVerticalLayout, UIText...
UILayout HorizontalRebuildLayout
UIHorizontalLayout calculation.
UILayout VerticalRebuildLayout
UIVerticalLayout calculation.
UILayout GridRebuildLayout
UIGridLayout calculation.
All cost of LGUI's EventSystem in game thread. LGUI will use ray and do raycast, execute event on hit object.
LGUILifeCycleBehaviour Start
LGUILifeCycleBehaviour Update
All cost of LGUILifeCycleBehaviour's Update function in game thread.