[Solved] 'DefaultTexturePlatform' is not valid with the current texture type 'Default' (Script)

A solution to use script the TextureImporter with a different format than dxt and RGBA32.

Change the default texture format to BC7 or any different format by script and unity editor does it's job without an error.

If you have an existing Texture2D changed by setpixel() or data[] and want to save and reload. I can recommended to use the following simple code.

using System.IO; is required to use File.xxxxxx

Code (CSharp):

1. byte[] bytes = mytex2D.EncodeToTGA();
2. var filepath_relative = "MyNewTexture/" + FName + ".tga";     /// ... path to .../Assets/MyNewTexture/
3. var path = Application.dataPath + "/" + filepath_relative;    /// ... Application.dataPath includes "...../Assets"
4. File.WriteAllBytes(path, bytes);
5.  
6. /// ... Tell unity to add this file. Otherwise it does not show up and its not accessible
7. AssetDatabase.ImportAsset("Assets" + filepath_relative);
8.  

Change the compression format from dxt and re-import again.

Code (CSharp):

1. TextureImporter textureImporter = (TextureImporter)TextureImporter.GetAtPath("Assets" + filepath_relative);
2. textureImporter.maxTextureSize = 4096;
3. textureImporter.textureType = TextureImporterType.Default;
4. textureImporter.textureShape = TextureImporterShape.Texture2D;
5. textureImporter.textureCompression = TextureImporterCompression.Uncompressed;
6. textureImporter.crunchedCompression = false;
7. textureImporter.compressionQuality = 0;
8. textureImporter.mipmapEnabled = true;
9. textureImporter.sRGBTexture = true;
10. textureImporter.isReadable = true;
11.  
12. TextureImporterPlatformSettings platform = new TextureImporterPlatformSettings();
13. platform.name = "Standalone";       // ... important
14. platform.overridden = true;        // ... important
15. platform.format = TextureImporterFormat.BC7;
16. platform.textureCompression = TextureImporterCompression.Compressed;
17. platform.compressionQuality = 0;
18. platform.maxTextureSize = 4096;
19.                  
20. textureImporter.SetPlatformTextureSettings(platform);
21.  
22. textureImporter.SaveAndReimport();
23. AssetDatabase.Refresh();