My custom viewport has a rotation of 90 degrees moving to UE 5.6

Hello,

Everything is said in the title. In our project, we created a map system displayed in a custom viewport created this way:

`TSharedRef SWMViewport::MakeEditorViewportClient()
{
//Instantiate the Viewport Client with a WorldManager Scene
FWMScene* newScene = new FWMScene(SharedThis(this));
newScene->Populate();

LevelViewportClient = MakeShared(newScene, SharedThis(this));

//Client Settings
//FIntPoint viewportOrigin, viewportSize;
LevelViewportClient->SetCameraSpeedScalar(8);
LevelViewportClient->ViewportType = LVT_OrthoXY;
LevelViewportClient->SetViewMode(EViewModeIndex::VMI_Unlit);
FVector vDefaultCenter = UProjectionUtils::GetWorldOrigin(false);
if ( vDefaultCenter.X == 0. && vDefaultCenter.Y == 0.) // no world origin, show all the globe
LevelViewportClient->SetOrthoZoom(31000000000.);
else
LevelViewportClient->SetOrthoZoom(100000000.);
LevelViewportClient->OverrideFarClipPlane(FAR_CLIP_PLANE);

LevelViewportClient->SetShowBounds(true);

return LevelViewportClient.ToSharedRef();
}`It was working well so far up to Unreal 5.5:

[Image Removed]

but moving to Unreal 5.6, we met this result which seems consistent but with a global rotation of 90 degrees:

[Image Removed]

Would you have any idea of what could have triggered this issue, a new parameter of the viewport to set in Unreal 5.6, a default value that could have changed somewhere? On our side, there is not a lot of changes for this version switch.

Any help will be welcome, thank you,

Philippe

Hi [mention removed]​,

Unreal Engine is undergoing several changes in version 5.6, one of which involves a transition toward a Left-Up-Forward (LUF) coordinate system. As part of this shift, some viewport behaviors, like the orthographic view orientation you mentioned are starting to reflect this new system.

Tim Sweeney(Epic CEO) provided more context about this change here: https://x.com/TimSweeneyEpic/status/1930678660098408669

This change is part of Epic’s roadmap, the goal is to align Unreal Engine with more standard 3D conventions. Epic has started introducing helper C++ functions to ease the transition.

If needed, I can reach out to Epic to check whether there’s any way to customize or override the new axis behavior in the editor views. That said, since this change will affect future engine versions as well, I’d recommend beginning to adapt to the new orientation as there might be more systems being affected by this change.

Best,

Joan

Hi Joan,

Ho! I missed that information! I guess I will have to adapt my code.

Thank you for your answer and the link,

Philippe