TextAssetPostProcessor.cs

// Unity C# reference source
// Copyright (c) Unity Technologies. For terms of use, see
// https://unity3d.com/legal/licenses/Unity_Reference_Only_License

using System;
using UnityEngine;
using UnityEngine.TextCore.Text;


namespace UnityEditor.TextCore.Text
{
    /// <summary>
    /// Asset post processor used to handle text assets changes.
    /// This includes tracking of changes to textures used by sprite assets as well as font assets potentially getting updated outside of the Unity editor.
    /// </summary>
    internal class TextAssetPostProcessor : AssetPostprocessor
    {
        private static void OnPostprocessAllAssets(string[] importedAssets, string[] deletedAssets, string[] movedAssets, string[] movedFromAssetPaths)
        {
            bool textureImported = false;
            foreach (var asset in importedAssets)
            {
                Type assetType = AssetDatabase.GetMainAssetTypeAtPath(asset);
                if (assetType == typeof(FontAsset))
                {
                    FontAsset fontAsset = AssetDatabase.LoadAssetAtPath(asset, typeof(FontAsset)) as FontAsset;
                    // Only refresh font asset definition if font asset was previously initialized.
                    if (fontAsset != null && fontAsset.m_CharacterLookupDictionary != null)
                        TextEditorResourceManager.RegisterFontAssetForDefinitionRefresh(fontAsset);
                    continue;
                }

                if (assetType == typeof(Texture2D))
                    textureImported = true;

                if (assetType == typeof(Font))
                    EditorApplication.delayCall += () => UpdateFallbackFontReferences(asset);
            }

            // If textures were imported, issue callback to any potential text objects that might require updating.
            if (textureImported)
                TextEventManager.ON_SPRITE_ASSET_PROPERTY_CHANGED(true, null);
        }

        static void UpdateFallbackFontReferences(string fontPath)
        {
            TrueTypeFontImporter fontImporter = AssetImporter.GetAtPath(fontPath) as TrueTypeFontImporter;
            if (fontImporter != null)
                fontImporter.fontReferences = fontImporter.LookupFallbackFontReferences(fontImporter.fontNames);
        }
    }

    internal class TMP_FontAssetPostProcessor : AssetModificationProcessor
    {
        static AssetDeleteResult OnWillDeleteAsset(string path, RemoveAssetOptions opt)
        {
            if (AssetDatabase.GetMainAssetTypeAtPath(path) == typeof(FontAsset))
                TextResourceManager.RebuildFontAssetCache();

            return AssetDeleteResult.DidNotDelete;
        }
    }
}