Fg-optional-arabic.bin

# Write header + body with open(output_bin_path, 'wb') as out: out.write(magic) out.write(struct.pack('<I', version)) out.write(struct.pack('<I', rule_count)) out.write(struct.pack('<I', 16)) # offset to body (after header) out.write(body)

# Prepare header magic = b'FGOA' version = data['version'] rules = data['optional_features'] rule_count = len(rules)

# Hypothetical compiler hb-compile-features -f optional-arabic.txt -o fg-optional-arabic.bin 4.1 Loading in a C/C++ Application #include <stdio.h> #include <stdint.h> typedef struct uint32_t magic; uint32_t version; uint32_t rule_count; uint32_t body_offset; FGHeader; fg-optional-arabic.bin

print(f"Generated output_bin_path with rule_count rules") If this file is intended for a specific engine, use its tooling:

FGHeader* load_fg_optional(const char* path) FILE* f = fopen(path, "rb"); if (!f) return NULL; FGHeader* hdr = malloc(sizeof(FGHeader)); fread(hdr, sizeof(FGHeader), 1, f); if (hdr->magic != 0x414F4746) // 'FGOA' in little-endian free(hdr); fclose(f); return NULL; # Write header + body with open(output_bin_path, 'wb')

body.append(rule.get('priority', 50))

// ... load rule table from body_offset fclose(f); return hdr; 'wb') as out: out.write(magic) out.write(struct.pack('&lt

def parse_header(self): self.magic = self.data[:4] self.version = int.from_bytes(self.data[4:8], 'little') self.rule_count = int.from_bytes(self.data[8:12], 'little') # ... parse rules When shaping Arabic text, after mandatory shaping, apply optional rules:

# Write each rule as: input_len (1B), inputs (4B each), output_len (1B), outputs (4B each), priority (1B) for rule in rules: inputs = rule['input'] outputs = rule['output'] if isinstance(rule['output'], list) else [rule['output']]

# Buffer for body body = bytearray()

body.append(len(inputs)) for ch in inputs: body.extend(struct.pack('<I', ch)) # Unicode codepoint