Generated lightmaps are removed on unity play

[monkeybrother_1]

I'm playing around with the lightmapper, but when I press play, all lightmaps are cleared. Is this correct beta behaviour or am I missing something?

[ChrisHekman]

Unity uses an object called LightingDataAsset to store its lightmaps. Regrettably unity does not expose the data in this object.
Ref: https://docs.unity3d.com/ScriptReferenc ... Asset.html https://docs.unity3d.com/Manual/LightmapSnapshot.html

In order to make them work in play mode you will need to set them via script at the start of your scene load.
Ref: https://docs.unity3d.com/ScriptReferenc ... pData.html
We are looking into making a script to do this for the user.

[monkeybrother_1]

Unity uses an object called LightingDataAsset to store its lightmaps. Regrettably unity does not expose the data in this object.
Ref: https://docs.unity3d.com/ScriptReferenc ... Asset.html https://docs.unity3d.com/Manual/LightmapSnapshot.html

In order to make them work in play mode you will need to set them via script at the start of your scene load.
Ref: https://docs.unity3d.com/ScriptReferenc ... pData.html
We are looking into making a script to do this for the user.

Ok. Do you have an example that shows how this could look in code?

[ChrisHekman]

Similar to this

Code: Select all

	void SetLightmaps( List<Texture2D> LightMaps, List<Texture2D> DirectionMaps)
	{
		LightmapData[] lightmapData= new LightmapData[LightMaps.Size];

			for(int i = 0; i < LightMaps.Size; i++)
			{
				lightmapData[i] = new LightmapData();
				lightmapData[i].lightmapColor = LightMaps[i];
				lightmapData[i].lightmapDir = DirectionalMaps[i];
			}

			LightmapSettings.lightmapsMode = LightmapsMode.CombinedDirectional;;
			LightmapSettings.lightmaps = lightmapData;	
	}

[OnlyVR]

How to bake the lightmaps? I can successfully render in PBR Viewport but "PBR Lightmapping" creates black PBRLightmap_N_LIGHT_DIRECTION.png and PBRLightmap_N_IRRADIANCE.exr files.
What am I missing ? Any special settings for camera etc?

My bad, I forgot to set my light as static.

[ChrisHekman]

My bad, I forgot to set my light as static.

I have run into that problem so many times.

[OnlyVR]

I've tried to use the script to assign the lightmaps in runtime mode but it doesn't work form. Actually my script is a little bit more complicated:

void Start () {

string m_Scene = SceneManager.GetActiveScene().name;
string m_pathLigtmap = "Assets/" + m_Scene + "/Octane/";

DirectoryInfo m_dir = new DirectoryInfo(m_pathLigtmap);
FileInfo[] fileInfoLightMaps = m_dir.GetFiles("*_BEAUTY_DENOISER_OUTPUT.exr");
FileInfo[] fileInfoDirectionalMaps = m_dir.GetFiles("*_LIGHT_DIRECTION.png");

LightmapData[] lightmapData = new LightmapData[fileInfoLightMaps.Length];

for (int i = 0; i < fileInfoLightMaps.Length; i++)
{
lightmapData = new LightmapData();
lightmapData.lightmapColor = (Texture2D)UnityEditor.AssetDatabase.LoadAssetAtPath(m_pathLigtmap + fileInfoLightMaps.Name, typeof(Texture2D));
lightmapData.lightmapDir = (Texture2D)UnityEditor.AssetDatabase.LoadAssetAtPath(m_pathLigtmap + fileInfoDirectionalMaps.Name, typeof(Texture2D));
}

LightmapSettings.lightmapsMode = LightmapsMode.CombinedDirectional; ;
LightmapSettings.lightmaps = lightmapData;
}

I can see the script correctly assigned the lightmapper, but in the game window there is no GI light.
Any idea?

[ChrisHekman]

I've tried to use the script to assign the lightmaps in runtime mode but it doesn't work form. Actually my script is a little bit more complicated:

void Start () {

string m_Scene = SceneManager.GetActiveScene().name;
string m_pathLigtmap = "Assets/" + m_Scene + "/Octane/";

DirectoryInfo m_dir = new DirectoryInfo(m_pathLigtmap);
FileInfo[] fileInfoLightMaps = m_dir.GetFiles("*_BEAUTY_DENOISER_OUTPUT.exr");
FileInfo[] fileInfoDirectionalMaps = m_dir.GetFiles("*_LIGHT_DIRECTION.png");

LightmapData[] lightmapData = new LightmapData[fileInfoLightMaps.Length];

for (int i = 0; i < fileInfoLightMaps.Length; i++)
{
lightmapData = new LightmapData();
lightmapData.lightmapColor = (Texture2D)UnityEditor.AssetDatabase.LoadAssetAtPath(m_pathLigtmap + fileInfoLightMaps.Name, typeof(Texture2D));
lightmapData.lightmapDir = (Texture2D)UnityEditor.AssetDatabase.LoadAssetAtPath(m_pathLigtmap + fileInfoDirectionalMaps.Name, typeof(Texture2D));
}

LightmapSettings.lightmapsMode = LightmapsMode.CombinedDirectional; ;
LightmapSettings.lightmaps = lightmapData;
}

I can see the script correctly assigned the lightmapper, but in the game window there is no GI light.
Any idea?

This looks correct.

Couple of possible issues
- "Baked Lightmap" atlas info was not saved to scene.
You can check this by selecting a static MeshRenderer. In the inspector check Lightmap Settings -> Baked Lightmap
If the atlas is 65535 that means it did not save its atlas info.

- Textures are not found by the assetdatabase and the lightmapsettings are filled by null textures

- Script start function is not called when going into play mode.


Additional comment
- "UnityEditor.AssetDatabase" is not useable from a standalone build of your game.
My advice would be to do the following:

Code: Select all

public Texture2D[] LightMaps;
public Texture2D[] DirectionalMaps;
void Start () {
...
}

And then fill those lists manually.

[markjackson]

Unity often resets certain settings when you hit "Play." Check if there are any options in the lighting settings or lightmapper that might prevent lightmaps from being cleared. If the problem persists, consider reporting it to the development team.