The Future of SC4 Modding: The Matter of Digital vs. Disc, and Windows vs. macOS in the DLL Era

This is a repost of a thread I started over at Simtropolis.

There are currently several different versions of SimCity 4 Deluxe out in the wild, including the various digital editions (i.e., GOG, Steam, and the now-patched EA App version), the original disc version, and the Steam and App Store versions of Aspyr’s macOS port of the game.

As one may have noticed while scrolling the STEX in the past three months, a once uncommon, “Holy Grail” type of mod has begun to appear with some frequency: DLL mods.  DLL mods are capable of modifying aspects of the game that have been previously off-limits to SC4 modders over the past 20 years.  The two best-known DLL mods prior to this point are, of course, the SC4 Extra Cheats DLL, a file Buggi was authorized to release from the original developers at Maxis, and simmaster07’s revolutionary SC4Fix, which fixed two of the most notorious bugs with the game in a modded environment: the Puzzle Piece vs. Transit-Enabled Lot CTD, and the Prop Pox.

Thanks to the efforts of those continuing simmaster07’s line of work, namely Null 45 and memo, these sorts of revolutions are about to become more commonplace, bringing with them everything from improved game stability on modern systems, to long-requested new features and quality-of-life (QoL) improvements.  Null 45 has already released over a dozen DLL mods on the STEX since November, one of the most recent of which allows more Building Styles.  While I can’t reveal too much at this point in time, I will note that DLL files will become important components of major SC4 mods in the very near future.  Suffice to say, we’re entering a very exciting time in the SC4 modding community.

There is, however, one caveat with this development: these new DLL mods will only work with Version 1.1.641 digital editions of the game on the Windows platform, while the older Windows disc versions and the Aspyr macOS port (in all its guises) will not be supported.

To those users who are running those versions, this almost certainly comes as a grave disappointment.  There are, however, technical reasons that pose essentially insurmountable barriers toward bringing this new and exciting DLL-based functionality to those versions of the game, and effectively render them “legacy versions” of SC4:

• Back in December 2017, simmaster07 had produced a mod known as SC4MacInjector, which provided a means for DLL-based mods to be converted into .so files and run in the macOS port via injection.  Unfortunately, the changes that Apple made in macOS Catalina (10.15) effectively broke SC4MacInjector permanently, forcing simmaster07 to discontinue it in June 2020.  With Apple moving to discontinue x86 architecture support in the near future, SC4MacInjector’s days were likely numbered either way.
• With regards to the Windows disc-based versions of SC4, Microsoft’s removal of the secdrv.sys driver from Windows 10 effectively broke the SafeDisc copy protection system that EA used, thereby preventing the disc version from running (at least without complicated or legally questionable workarounds).  The fact that the disc versions’ hardcoded aspects are also differently-structured (and encrypted) complicates the prospects of providing support for it to the point of practical impossibility.

For those of you running the Aspyr macOS port, unfortunately, Apple’s constant drastic changes to macOS and their entire hardware architecture have taken that version of the game out of the running.  The only option to play on Mac with these new developments is some form of dual-booting and/or WINE with a digital copy of the Windows version of the game (which can readily be made to run on Linux).  If you happen to be playing on the Steam version, you have access to the Windows version at no additional cost, since SC4 is a SteamPlay title.  Unfortunately, with the App Store version, there is no such crossplay option available, and one will have to purchase a new copy.

In order for these developments to work directly with the Mac version, Aspyr would need to patch the game, preferably allow direct reading of .so files (the Mac equivalent of DLL files) without code injection or running afoul of Apple’s “Hardened Runtime” feature.  Given that Aspyr, while updating their port to deal with Apple’s myriad drastic mandatory architecture changes over the years, has refrained from even issuing an equivalent of the 20-year-old 1.1.638/EP1 patch for the Mac port, or the almost-as-old 1.1.640/BAT nightlighting patch–the odds are even longer that they would do this.

For those on the disc on Windows, acquiring a legal Version 1.1.641 digital copy is the only way to get this functionality.  Redeeming your CD Key with EA (via the EA App–EA Help can assist with this if one encounters difficulties) is one way to get one without having to buy the game again.  The other option is to wait for the GOG edition to go on sale (typical sale price is US$4.99)–since GOG’s digital edition is DRM-free, it’ll be more “yours” than the disc version ever could be, as evidenced by the disc’s old DRM/copy protection scheme thwarting its use on newer versions of Windows.  (And acquiring some sort of pirated/”cracked” version is, of course, a violation of community rules, including ST Guidelines, Section 5(a).)

Again, in short:

Version 1.1.641 Windows Digital Copies – Supported

Version 1.1.640 and earlier Windows Disc Copies – Not Supported (but CD Key may be redeemable for free Version 1.1.641 digital copy with EA)

macOS Port on Steam – Not Supported (but SteamPlay offers free Windows Version 1.1.641 digital copy with Steam for dual-boot/WINE use)

macOS Port on App Store – Not Supported (no option for compatible free replacement, purchase new copy)

All Other Versions – Not Supported (no option for compatible free replacement, purchase new copy)

Pirated/”Cracked” Copies – Not Supported, and in violation of community rules (i.e., ST Guidelines, Section 5(a).)

-Tarkus