Add script to generate decompressed baseROM

tools/generate_decompressed_rom.py

@@ -0,0 +1,123 @@
+#!/usr/bin/env python3
+
+from typing import BinaryIO
+import gzip
+import io
+import shutil
+
+next_available_free_space = 0x2000000
+
+overlays = [
+    {
+        "name": "global_asm",
+        "codeROMAddress": 0x113F0,
+        "dataROMAddress": 0xC29D4,
+        "dataCompressedSize": 0x949C, # - 8 for length without gzip footer
+        # Note: These byte arrays should not contain the gzip footer
+        # codeCompressedData: [], // Will be written to ROM
+        # dataCompressedData: [], // Will be written to ROM directly after .code, regardless of the original .data address
+    },
+    {
+        "name": "menu",
+        "codeROMAddress": 0xCBE70,
+        "dataROMAddress": 0xD4554,
+        "dataCompressedSize": 0x5A2, # - 8 for length without gzip footer
+    },
+    {
+        "name": "multiplayer",
+        "codeROMAddress": 0xD4B00,
+        "dataROMAddress": 0xD69F8,
+        "dataCompressedSize": 0xFB, # - 8 for length without gzip footer
+    },
+    {
+        "name": "minecart",
+        "codeROMAddress": 0xD6B00,
+        "dataROMAddress": 0xD98A0,
+        "dataCompressedSize": 0x197, # - 8 for length without gzip footer
+    },
+    {
+        "name": "bonus",
+        "codeROMAddress": 0xD9A40,
+        "dataROMAddress": 0xDF346,
+        "dataCompressedSize": 0x2AB, # - 8 for length without gzip footer
+    },
+    {
+        "name": "race",
+        "codeROMAddress": 0xDF600,
+        "dataROMAddress": 0xE649A,
+        "dataCompressedSize": 0x2DB, # - 8 for length without gzip footer
+    },
+    {
+        "name": "critter",
+        "codeROMAddress": 0xE6780,
+        "dataROMAddress": 0xE9D17,
+        "dataCompressedSize": 0x38C, # - 8 for length without gzip footer
+    },
+    {
+        "name": "boss",
+        "codeROMAddress": 0xEA0B0,
+        "dataROMAddress": 0xF388F,
+        "dataCompressedSize": 0x90A, # - 8 for length without gzip footer
+    },
+    {
+        "name": "arcade",
+        "codeROMAddress": 0xF41A0,
+        "dataROMAddress": 0xFB42C,
+        "dataCompressedSize": 0x1EC4, # - 8 for length without gzip footer
+    },
+    {
+        "name": "jetpac",
+        "codeROMAddress": 0xFD2F0,
+        "dataROMAddress": 0x1010FD,
+        "dataCompressedSize": 0x936, # - 8 for length without gzip footer
+    },
+]
+
+def readAndDecompressOverlays(fr : BinaryIO):
+    for x in overlays:
+        x["codeCompressedSize"] = x["dataROMAddress"] - x["codeROMAddress"]
+        fr.seek(x["codeROMAddress"], io.SEEK_SET)
+        print(f"    - Read {x['name']}.code compressed from {hex(fr.tell())}")
+        x["codeCompressedData"] = fr.read(x['codeCompressedSize'])
+        x["codeDecompressedData"] = gzip.decompress(x["codeCompressedData"])
+        print(f"    - Read {x['name']}.data compressed from {hex(fr.tell())}")
+        x["dataCompressedData"] = fr.read(x['dataCompressedSize'])
+        x["dataDecompressedData"] = gzip.decompress(x["dataCompressedData"])
+
+def alignHex10(fr: BinaryIO):
+    # Get the current position
+    current_position = fr.tell()
+
+    # Calculate the offset to the desired alignment
+    alignment = 0x10
+    offset = alignment - (current_position % alignment)
+
+    # Adjust the position by seeking with the offset
+    if abs(offset) < alignment:
+        fr.seek(offset, io.SEEK_CUR)
+
+    return fr.tell()
+
+def writeDecompressedOverlaysToROM(fr : BinaryIO):
+    fr.seek(next_available_free_space, io.SEEK_SET)
+    for x in overlays:
+        decompressedCodeStart = alignHex10(fr)
+        fr.write(x["codeDecompressedData"])
+        print(f"    - Wrote {x['name']}.code to {hex(decompressedCodeStart)}")
+        decompressedDataStart = alignHex10(fr)
+        fr.write(x["dataDecompressedData"])
+        print(f"    - Wrote {x['name']}.data to {hex(decompressedDataStart)}")
+
+# Make a copy of the baseROM to be used as the decompressed baseROM
+shutil.copyfile('baserom.us.z64', 'baserom.us.decompressed.z64')
+
+# Open the decompressed ROM
+with open('baserom.us.decompressed.z64', "r+b") as fh:
+    # Decompress all code and data segments
+    print("[1 / 2] Decompressing overlays...")
+    readAndDecompressOverlays(fh)
+
+    # Concatenate the decompressed segments onto the end of the ROM file, align by 0x10 bytes
+    print("[2 / 2] Writing decompressed overlays...")
+    writeDecompressedOverlaysToROM(fh)
+    print("Decompressed ROM created.")