Merge "Use variable definition for variable font family" into main

3 files changed, 82 insertions, 6 deletions

diff --git a/graphics/java/android/graphics/FontListParser.java b/graphics/java/android/graphics/FontListParser.java
index 674246acafef..735bc180c015 100644
--- a/graphics/java/android/graphics/FontListParser.java
+++ b/graphics/java/android/graphics/FontListParser.java
@@ -16,6 +16,10 @@
 
 package android.graphics;
 
+import static android.graphics.fonts.FontFamily.Builder.VARIABLE_FONT_FAMILY_TYPE_NONE;
+import static android.graphics.fonts.FontFamily.Builder.VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ITAL;
+import static android.graphics.fonts.FontFamily.Builder.VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ONLY;
+import static android.graphics.fonts.FontFamily.Builder.VARIABLE_FONT_FAMILY_TYPE_TWO_FONTS_WGHT;
 import static android.text.FontConfig.NamedFamilyList;
 
 import android.annotation.NonNull;
@@ -28,6 +32,7 @@ import android.os.Build;
 import android.os.LocaleList;
 import android.text.FontConfig;
 import android.util.ArraySet;
+import android.util.Log;
 import android.util.Xml;
 
 import org.xmlpull.v1.XmlPullParser;
@@ -256,6 +261,7 @@ public class FontListParser {
         final String lang = parser.getAttributeValue("", "lang");
         final String variant = parser.getAttributeValue(null, "variant");
         final String ignore = parser.getAttributeValue(null, "ignore");
+        final String varFamilyTypeStr = parser.getAttributeValue(null, "varFamilyType");
         final List<FontConfig.Font> fonts = new ArrayList<>();
         while (keepReading(parser)) {
             if (parser.getEventType() != XmlPullParser.START_TAG) continue;
@@ -278,12 +284,45 @@ public class FontListParser {
                 intVariant = FontConfig.FontFamily.VARIANT_ELEGANT;
             }
         }
+        int varFamilyType = VARIABLE_FONT_FAMILY_TYPE_NONE;
+        if (varFamilyTypeStr != null) {
+            varFamilyType = Integer.parseInt(varFamilyTypeStr);
+            if (varFamilyType <= -1 || varFamilyType > 3) {
+                Log.e(TAG, "Error: unexpected varFamilyType value: " + varFamilyTypeStr);
+                varFamilyType = VARIABLE_FONT_FAMILY_TYPE_NONE;
+            }
+
+            // validation but don't read font content for performance reasons.
+            switch (varFamilyType) {
+                case VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ONLY:
+                    if (fonts.size() != 1) {
+                        Log.e(TAG, "Error: Single font support wght axis, but two or more fonts are"
+                                + " included in the font family.");
+                        varFamilyType = VARIABLE_FONT_FAMILY_TYPE_NONE;
+                    }
+                    break;
+                case VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ITAL:
+                    if (fonts.size() != 1) {
+                        Log.e(TAG, "Error: Single font support both ital and wght axes, but two or"
+                                + " more fonts are included in the font family.");
+                        varFamilyType = VARIABLE_FONT_FAMILY_TYPE_NONE;
+                    }
+                    break;
+                case VARIABLE_FONT_FAMILY_TYPE_TWO_FONTS_WGHT:
+                    if (fonts.size() != 2) {
+                        Log.e(TAG, "Error: two fonts that support wght axis, but one or three or"
+                                + " more fonts are included in the font family.");
+                        varFamilyType = VARIABLE_FONT_FAMILY_TYPE_NONE;
+                    }
+            }
+        }
 
         boolean skip = (ignore != null && (ignore.equals("true") || ignore.equals("1")));
         if (skip || fonts.isEmpty()) {
             return null;
         }
-        return new FontConfig.FontFamily(fonts, LocaleList.forLanguageTags(lang), intVariant);
+        return new FontConfig.FontFamily(fonts, LocaleList.forLanguageTags(lang), intVariant,
+                varFamilyType);
     }
 
     private static void throwIfAttributeExists(String attrName, XmlPullParser parser) {
diff --git a/graphics/java/android/graphics/fonts/FontFamily.java b/graphics/java/android/graphics/fonts/FontFamily.java
index 5e4110590325..4c753565eb5b 100644
--- a/graphics/java/android/graphics/fonts/FontFamily.java
+++ b/graphics/java/android/graphics/fonts/FontFamily.java
@@ -18,7 +18,10 @@ package android.graphics.fonts;
 
 import static com.android.text.flags.Flags.FLAG_DEPRECATE_FONTS_XML;
 
+import static java.lang.annotation.RetentionPolicy.SOURCE;
+
 import android.annotation.FlaggedApi;
+import android.annotation.IntDef;
 import android.annotation.IntRange;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
@@ -32,6 +35,7 @@ import dalvik.annotation.optimization.FastNative;
 
 import libcore.util.NativeAllocationRegistry;
 
+import java.lang.annotation.Retention;
 import java.util.ArrayList;
 import java.util.Set;
 
@@ -184,32 +188,59 @@ public final class FontFamily {
         }
 
         /**
+         * A special variable font family type that indicates `analyzeAndResolveVariableType` could
+         * not be identified the variable font family type.
+         *
          * @see #buildVariableFamily()
          * @hide
          */
         public static final int VARIABLE_FONT_FAMILY_TYPE_UNKNOWN = -1;
 
         /**
+         * A variable font family type that indicates no variable font family can be used.
+         *
+         * The font family is used as bundle of static fonts.
          * @see #buildVariableFamily()
          * @hide
          */
         public static final int VARIABLE_FONT_FAMILY_TYPE_NONE = 0;
         /**
+         * A variable font family type that indicates single font file can be used for multiple
+         * weight. For the italic style, fake italic may be applied.
+         *
          * @see #buildVariableFamily()
          * @hide
          */
         public static final int VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ONLY = 1;
         /**
+         * A variable font family type that indicates single font file can be used for multiple
+         * weight and italic.
+         *
          * @see #buildVariableFamily()
          * @hide
          */
         public static final int VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ITAL = 2;
         /**
+         * A variable font family type that indicates two font files are included in the family:
+         * one can be used for upright with various weights, the other one can be used for italic
+         * with various weights.
+         *
          * @see #buildVariableFamily()
          * @hide
          */
         public static final int VARIABLE_FONT_FAMILY_TYPE_TWO_FONTS_WGHT = 3;
 
+        /** @hide */
+        @Retention(SOURCE)
+        @IntDef(prefix = { "VARIABLE_FONT_FAMILY_TYPE_" }, value = {
+                VARIABLE_FONT_FAMILY_TYPE_UNKNOWN,
+                VARIABLE_FONT_FAMILY_TYPE_NONE,
+                VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ONLY,
+                VARIABLE_FONT_FAMILY_TYPE_SINGLE_FONT_WGHT_ITAL,
+                VARIABLE_FONT_FAMILY_TYPE_TWO_FONTS_WGHT
+        })
+        public @interface VariableFontFamilyType {}
+
         /**
          * The registered italic axis used for adjusting requested style.
          * https://learn.microsoft.com/en-us/typography/opentype/spec/dvaraxistag_ital
@@ -222,7 +253,9 @@ public final class FontFamily {
          */
         private static final int TAG_wght = 0x77676874;  // w(0x77), g(0x67), h(0x68), t(0x74)
 
-        private static int analyzeAndResolveVariableType(ArrayList<Font> fonts) {
+        /** @hide */
+        public static @VariableFontFamilyType int analyzeAndResolveVariableType(
+                ArrayList<Font> fonts) {
             if (fonts.size() > 2) {
                 return VARIABLE_FONT_FAMILY_TYPE_UNKNOWN;
             }
diff --git a/graphics/java/android/graphics/fonts/SystemFonts.java b/graphics/java/android/graphics/fonts/SystemFonts.java
index 9810022abfed..d4e35b30c8d0 100644
--- a/graphics/java/android/graphics/fonts/SystemFonts.java
+++ b/graphics/java/android/graphics/fonts/SystemFonts.java
@@ -121,7 +121,8 @@ public final class SystemFonts {
 
 
         final FontFamily defaultFamily = defaultFonts.isEmpty() ? null : createFontFamily(
-                defaultFonts, languageTags, variant, false, cache);
+                defaultFonts, languageTags, variant, xmlFamily.getVariableFontFamilyType(), false,
+                cache);
         // Insert family into fallback map.
         for (int i = 0; i < fallbackMap.size(); i++) {
             final String name = fallbackMap.keyAt(i);
@@ -138,8 +139,8 @@ public final class SystemFonts {
                     familyListSet.familyList.add(defaultFamily);
                 }
             } else {
-                final FontFamily family = createFontFamily(fallback, languageTags, variant, false,
-                        cache);
+                final FontFamily family = createFontFamily(fallback, languageTags, variant,
+                        xmlFamily.getVariableFontFamilyType(), false, cache);
                 if (family != null) {
                     familyListSet.familyList.add(family);
                 } else if (defaultFamily != null) {
@@ -155,6 +156,7 @@ public final class SystemFonts {
             @NonNull List<FontConfig.Font> fonts,
             @NonNull String languageTags,
             @FontConfig.FontFamily.Variant int variant,
+            int varFamilyType,
             boolean isDefaultFallback,
             @NonNull Map<String, ByteBuffer> cache) {
         if (fonts.size() == 0) {
@@ -196,7 +198,7 @@ public final class SystemFonts {
             }
         }
         return b == null ? null : b.build(languageTags, variant, false /* isCustomFallback */,
-                isDefaultFallback, FontFamily.Builder.VARIABLE_FONT_FAMILY_TYPE_NONE);
+                isDefaultFallback, varFamilyType);
     }
 
     private static void appendNamedFamilyList(@NonNull FontConfig.NamedFamilyList namedFamilyList,
@@ -210,6 +212,7 @@ public final class SystemFonts {
             final FontFamily family = createFontFamily(
                     xmlFamily.getFontList(),
                     xmlFamily.getLocaleList().toLanguageTags(), xmlFamily.getVariant(),
+                    xmlFamily.getVariableFontFamilyType(),
                     true, // named family is always default
                     bufferCache);
             if (family == null) {
@@ -291,6 +294,7 @@ public final class SystemFonts {
             int configVersion
     ) {
         try {
+            Log.i(TAG, "Loading font config from " + fontsXml);
             return FontListParser.parse(fontsXml, systemFontDir, oemXml, productFontDir,
                                                 updatableFontMap, lastModifiedDate, configVersion);
         } catch (IOException e) {