Tips and Constraints
The system of Spatial Reality Display (SR Display) has some special aspects compared to other systems, such as the eye-tracking system and rendering system. The system is not the same as simple PC standalone applications and more similar to VR applications. That's why there are some tips and constraints.
Minimize the latency for good user experience
The short latency is very important for good user experience.
We strongly recommend to turn off VSync to minimize the latency. However, turing VSync off causes the tearing problem. If you cannot accept the tearing problem, you need to turn VSync on.
We also recommend to use Forward Shading.
In the Edit menu, open the Project Settings.
Select the Rendering tab on the left and locate the Forward Shading category.
Enable Forward Shading.
You will be prompted to restart the editor where after the restart, you can begin using the Forward Renderer options and features.
Also, you should be careful for optimizing the performance of your contents to reduce the latency. Even if VSync is turned off and Forward Shading is used, if the performance load of your application is heavy, the latency will be long.
This is very similar to the performance optimization for VR contents.
Camera Actor is not needed
You don't need to place a Camera Actor on maps. You can place one but it won't work correctly since SRDisplay Manager Actor will overwrites it's location and rotation. Place a SRDisplay Manager Actor to determine which part of a map to be rendered on SR Display.
Only one SRDisplay Manager on a map works correctly.
Spatial Clipping has side effects on some lights and shadows
Spatial Clipping changes the projection matrix, so that the depth is changed. Due to this, some lights and shadows may not render as expected.
Illumination of a Spot Light Actor will cause block noise as shown in the following image. The problem goes away by not using Forward Shading, but it will lead to a significant performance problem. So, we recommend not using Spatial Clipping with a Spot Light Actor at a same time.
Dynamic Shadow casted to an Actor whose Mobility setting is Movable will not be rendered correctly. If you use Spatial Clipping and some Movable Actors, we recommend disabling Dynamic Shadow.