Updated on 22nd Apr 2021

Limitations and Problems

Current Limitations

  • Normal Influence does not work on Forward Shading and Mobile. (Impossible to support, requires G-Buffer)
  • The Blend Mode Additive with Scene Color does not work on Forward Shading and Mobile. (Impossible to support, requires G-Buffer)
  • The Simple Light Painter does not work without Mobile HDR. (Requires SceneDepth)

Known Problems

  • Bugs related to the Vulkan RHI
    Reason: It has been reported that the SLP does not work as expected in Vulkan Forward Rendering. After testing it was discovered that different results and errors will appear on different machines. It is not clear what the cause of this problem is. (It's really weird to be honest.)
    These bugs are not limited to Forward Rendering and also happen in Deferred Rendering. Please report any additional Info you find about this on the Discord Server.

  • The SLP Editor Widget does not update the Light Meshes
    Reason: There is a small chance that the Editor Widget stops updating the Light Painter Meshes and Materials. This mostly happens when switching between Playing/Simulating and quitting the Game. This can be fixed by simply closing the Editor Widget and reopening again.

  • The performance in the Editor drops extremely with lots (100+) of Light Painters on Screen
    Reason: The Light Painters use a "Material Billboard" Component of UE4 which causes these Frame Drops. This ONLY happens in the Editor and will never be experienced in a shipped product.

  • Using the Light Painters on Mobile will result in a Crash.
    Reason: The GI System uses a Render Target, with automatic Mip Map generation, which causes UE4 to crash on Mobile. Disabling the automatic Mip Map generation will get rid of the Crash, but with decreased Quality and Accuracy in the GI Colors.

    ✅ FIXED in Version 1.1: The SLP does not use automatic Mip Map generation anymore and instead has a custom HLSL Shader to replace that.

Information about Mobile Support

There are still some issues with the GI System that make it impossible to support Mobile by default, but it is on the To-Do List and will hopefully be delivered in a future update.
✅ The Simple Light Painter now supports Mobile Platforms with Version 1.1!