Consolidate watch face fonts to 2 hours per font file with pure BMP East Asian fullwidth ideographs

Author: alexvanyo

wear-watchface-wff-resources/build.gradle.kts

@@ -108,17 +108,23 @@ private data class ConsolidatedHourGroup(
 )
 
 private val consolidatedHourGroups = listOf(
-    ConsolidatedHourGroup("hours_00_02", listOf("00", "01", "02")),
-    ConsolidatedHourGroup("hours_03_05", listOf("03", "04", "05")),
-    ConsolidatedHourGroup("hours_06_08", listOf("06", "07", "08")),
-    ConsolidatedHourGroup("hours_09_11", listOf("09", "10", "11")),
-    ConsolidatedHourGroup("hours_12_14", listOf("12", "13", "14")),
-    ConsolidatedHourGroup("hours_15_17", listOf("15", "16", "17")),
-    ConsolidatedHourGroup("hours_18_20", listOf("18", "19", "20")),
-    ConsolidatedHourGroup("hours_21_23", listOf("21", "22", "23")),
-    ConsolidatedHourGroup("hours_1_3", listOf("_1", "_2", "_3")),
-    ConsolidatedHourGroup("hours_4_6", listOf("_4", "_5", "_6")),
-    ConsolidatedHourGroup("hours_7_9", listOf("_7", "_8", "_9")),
+    ConsolidatedHourGroup("hours_00_01", listOf("00", "01")),
+    ConsolidatedHourGroup("hours_02_03", listOf("02", "03")),
+    ConsolidatedHourGroup("hours_04_05", listOf("04", "05")),
+    ConsolidatedHourGroup("hours_06_07", listOf("06", "07")),
+    ConsolidatedHourGroup("hours_08_09", listOf("08", "09")),
+    ConsolidatedHourGroup("hours_10_11", listOf("10", "11")),
+    ConsolidatedHourGroup("hours_12_13", listOf("12", "13")),
+    ConsolidatedHourGroup("hours_14_15", listOf("14", "15")),
+    ConsolidatedHourGroup("hours_16_17", listOf("16", "17")),
+    ConsolidatedHourGroup("hours_18_19", listOf("18", "19")),
+    ConsolidatedHourGroup("hours_20_21", listOf("20", "21")),
+    ConsolidatedHourGroup("hours_22_23", listOf("22", "23")),
+    ConsolidatedHourGroup("hours_1_2", listOf("_1", "_2")),
+    ConsolidatedHourGroup("hours_3_4", listOf("_3", "_4")),
+    ConsolidatedHourGroup("hours_5_6", listOf("_5", "_6")),
+    ConsolidatedHourGroup("hours_7_8", listOf("_7", "_8")),
+    ConsolidatedHourGroup("hours_9", listOf("_9")),
 )
 
 androidComponents {

wear-watchface-wff-resources/scripts/build_consolidated_hour_otf.py

@@ -43,34 +43,20 @@
 MAX_SUBROUTINES_PER_FONT = 1239
 
 
-def get_safe_bmp_codepoints():
+def get_safe_codepoints():
     """
-    Generates 54,000 safe East Asian Fullwidth/ideographic BMP codepoints:
+    Generates 36,000 pure East Asian Fullwidth (W) ideographs in the BMP (Plane 0):
     - Hour 0: CJK Unified Ideographs (0x4E00..0x944F, 18,000 characters)
     - Hour 1: Hangul Syllables + CJK Ext A + Yi (0xAC00.., 18,000 characters)
-    - Hour 2: PUA + Remaining CJK + Non-combining LTR BMP (18,000 characters)
+    Every character is 100% fullwidth square cell, strictly LTR, non-combining,
+    and natively supported by Android's Format 4 BMP cmap.
     """
     h0 = list(range(0x4E00, 0x4E00 + 18000))
     h1 = (list(range(0xAC00, 0xD7A4)) + list(range(0x3400, 0x4DC0)) + list(range(0xA000, 0xA490)))[:18000]
+    return h0 + h1
 
-    h2_filtered = []
-    for cp in list(range(0x0100, 0x0590)) + list(range(0x0900, 0xD800)) + list(range(0xE000, 0xFFFD)):
-        c = chr(cp)
-        cat = unicodedata.category(c)
-        bidi = unicodedata.bidirectional(c)
-        if cat in ("Mn", "Mc", "Me", "Cf", "Cc", "Cs", "Zl", "Zp", "Zs"):
-            continue
-        if bidi not in ("L", "ON", "EN"):
-            continue
-        if c in ("<", ">", "&", '"', "'"):
-            continue
-        if cp not in h0 and cp not in h1 and cp not in h2_filtered:
-            h2_filtered.append(cp)
-    h2 = h2_filtered[:18000]
-    return h0 + h1 + h2
 
-
-SAFE_BMP_CODEPOINTS = get_safe_bmp_codepoints()
+SAFE_CODEPOINTS = get_safe_codepoints()
 
 
 def parse_minute_data(file_path: str):
@@ -197,7 +183,7 @@ def build_consolidated_font(
         for gen in range(GENERATIONS_PER_MINUTE):
             canonical_idx = gen_map[gen]
             glyph_name = f"c_{hour_prefix}_{minute:02d}_{canonical_idx}"
-            cmap[SAFE_BMP_CODEPOINTS[base_frame_idx + gen]] = glyph_name
+            cmap[SAFE_CODEPOINTS[base_frame_idx + gen]] = glyph_name
 
         for canonical_idx, instances in glyph_instances.items():
             glyph_name = f"c_{hour_prefix}_{minute:02d}_{canonical_idx}"