Fix custom font fallback rendering

src/main/java/meteordevelopment/meteorclient/renderer/Fonts.java

@@ -17,6 +17,8 @@
 import meteordevelopment.meteorclient.utils.render.FontUtils;
 
 import java.io.File;
+import java.io.IOException;
+import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
@@ -25,6 +27,23 @@
 
 public class Fonts {
     public static final String[] BUILTIN_FONTS = {"JetBrains Mono", "Comfortaa", "Tw Cen MT", "Pixelation"};
+    private static final String[] FALLBACK_FONT_FAMILIES = {
+        "Noto Sans SC",
+        "Microsoft YaHei",
+        "Microsoft YaHei UI",
+        "DengXian",
+        "SimHei",
+        "SimSun",
+        "KaiTi",
+        "Microsoft JhengHei",
+        "Malgun Gothic",
+        "Yu Gothic",
+        "MS Gothic",
+        "Source Han Sans SC",
+        "WenQuanYi Zen Hei",
+        "PingFang SC",
+        "Hiragino Sans GB"
+    };
 
     public static String DEFAULT_FONT_FAMILY;
     public static FontFace DEFAULT_FONT;
@@ -90,4 +109,57 @@ public static FontFamily getFamily(String name) {
 
         return null;
     }
+
+    public static List<FontFace> getFallbackFonts(FontFace primary) {
+        List<FontFace> fonts = new ArrayList<>();
+
+        for (String familyName : FALLBACK_FONT_FAMILIES) {
+            FontFace font = getFallbackFont(familyName, primary);
+            if (font != null) {
+                fonts.add(font);
+                break;
+            }
+        }
+
+        return fonts;
+    }
+
+    public static List<ByteBuffer> readFontBuffers(FontFace primary) throws IOException {
+        List<ByteBuffer> buffers = new ArrayList<>();
+        buffers.add(primary.readToDirectByteBuffer());
+
+        for (FontFace fallbackFont : getFallbackFonts(primary)) {
+            try {
+                buffers.add(fallbackFont.readToDirectByteBuffer());
+            } catch (IOException e) {
+                MeteorClient.LOG.warn("Failed to load fallback font: {}", fallbackFont, e);
+            }
+        }
+
+        return buffers;
+    }
+
+    private static FontFace getFallbackFont(String familyName, FontFace primary) {
+        FontFamily family = getFamily(familyName);
+
+        if (family == null) {
+            String needle = familyName.toLowerCase();
+
+            for (FontFamily fontFamily : FONT_FAMILIES) {
+                if (fontFamily.getName().toLowerCase().contains(needle)) {
+                    family = fontFamily;
+                    break;
+                }
+            }
+        }
+
+        if (family == null) return null;
+
+        for (FontInfo.Type type : FontInfo.Type.values()) {
+            FontFace font = family.get(type);
+            if (font != null && !font.info.equals(primary.info)) return font;
+        }
+
+        return null;
+    }
 }

src/main/java/meteordevelopment/meteorclient/renderer/text/CustomTextRenderer.java

@@ -5,6 +5,7 @@
 
 package meteordevelopment.meteorclient.renderer.text;
 
+import meteordevelopment.meteorclient.renderer.Fonts;
 import meteordevelopment.meteorclient.renderer.MeshBuilder;
 import meteordevelopment.meteorclient.renderer.MeshRenderer;
 import meteordevelopment.meteorclient.renderer.MeteorRenderPipelines;
@@ -13,6 +14,7 @@
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
+import java.util.List;
 
 public class CustomTextRenderer implements TextRenderer {
     public static final Color SHADOW_COLOR = new Color(60, 60, 60, 180);
@@ -32,11 +34,11 @@ public class CustomTextRenderer implements TextRenderer {
     public CustomTextRenderer(FontFace fontFace) throws IOException {
         this.fontFace = fontFace;
 
-        ByteBuffer buffer = fontFace.readToDirectByteBuffer();
+        List<ByteBuffer> buffers = Fonts.readFontBuffers(fontFace);
 
         fonts = new Font[5];
         for (int i = 0; i < fonts.length; i++) {
-            fonts[i] = new Font(buffer, (int) Math.round(27 * ((i * 0.5) + 1)));
+            fonts[i] = new Font(buffers, (int) Math.round(27 * ((i * 0.5) + 1)));
         }
     }
 
@@ -120,6 +122,7 @@ public void end() {
 
         if (!scaleOnly) {
             mesh.end();
+            font.uploadPendingGlyphs();
 
             MeshRenderer.begin()
                 .attachments(Minecraft.getInstance().getMainRenderTarget())