Changes to texture get discarded

Unity Engine
1

Hi, I’m modifying a lightmap. All the changes are shown correctly in the game view and in the editor, however if I open the lightmap image in Photoshop, all the changes are gone. If I reimport the lightmaps, all the changes are also gone.

Here’s my code:

List <Color[]> lightmapsPixels = new List<Color[]>();

//Get all lightmap pixels
for (int i = 0; i < lightmapsList.Count; i++) {
	Texture2D lightmapTexture = LightmapSettings.lightmaps[i].lightmapFar;
	Helper.SetTextureImporterFormat(lightmapTexture, TextureImporterFormat.AutomaticTruecolor, true);   //Make the texture truecolor and readable
	lightmapsPixels.Add( lightmapTexture.GetPixels() );
}

... do the changes to lightmapsPixels data...

for (int i = 0; i < lightmapsPixels.Count; i++) {
	Texture2D lightmapTexture = LightmapSettings.lightmaps[i].lightmapFar;
	lightmapTexture.SetPixels( lightmapsPixels[i] );
	lightmapTexture.Apply();
	LightmapSettings.lightmaps[i].lightmapFar = lightmapTexture;
}

What am I doing wrong? Why aren’t my changes kept in the actual lightmap files?

Thanks!

2

Is it possible, that unity can only import EXR files, but it cannot save changes to them?