Lua Extensions - DLL Plugin

[Null 45 3,018]

A DLL Plugin for SimCity 4 that extends the game's Lua system with new functions. This file is a dependency for plugins that use the new Lua script functions.

This DLL provides a number of functions for the game's Lua scripts. See null45_lua_extensions.lua for a list of the provided functions, and null45_lua_extensions_tests.lua for examples of their use.

It also re-enables the Lua error logging that Maxis disabled in the retail version of the game. Note that due to the way that the game loads plugin Lua scripts, the error messages only give the line number within the script unless the error occurs within a function.

Download: https://community.simtropolis.com/files/file/36925-lua-extensions-dll/

Source Code: https://github.com/0xC0000054/sc4-lua-extensions

System Requirements

• SimCity 4 version 641
• Windows 10 or later
• Microsoft Visual C++ 2022 x86 Redistribute

The plugin may work on Windows 7 or later, but I do not have the ability to test that.

Installation

1. Close SimCity 4.
2. Copy SC4LuaExtensions.dll, and SC4LuaExtensions.dat into the top-level of the Plugins folder in the SimCity 4 installation directory or Documents/SimCity 4 directory.
3. Start SimCity 4.

Troubleshooting

The plugin should write a SC4LuaExtensions.log file in the same folder as the plugin.
The log contains status information for the most recent run of the plugin.

If you would like to make voluntary contributions to support me in continuing to create more content for SimCity 4, I accept donations via PayPal: https://paypal.me/0xC0000054

Thanks to the few people who have donated to me.

[Kel9509 1,357]

Wow.  I was looking at the list of LUA functions in your example and those are really, really powerful.  I know that you already highlighted the ability to take screenshots, but there are others that are really cool and might actually be very useful for modders in the future.  Like the ability to construct a particular building lot at a specified place.  This could make for some interesting reward lots that are auto-built.  Heck, you could auto-plop a lot, growify it with the cheat code, and then take a screenshot to capture your reward.  That sounds incredible.

The ability to get department budget income and expenses is also very interesting.  I assume that those amounts are the same as included in the budget table (and updated the same way?).  I recall in my update to the Census Repository that certain numbers weren't updated until the 28th of the month and they never really aligned with what was shown in the budget window. I wonder if it'd be possible to iron that out now with this new LUA coding...  Hmm.

(As an aside, I'm still working off of my wife's old laptop and hence it's very difficult to mod.  My new computer is coming along nicely though and I'm waiting for the motherboard to arrive before putting it together, hopefully next month.  Damn tariffs messed everything up, and it doesn't help that I'm an idiot and decided to build a top of the line system after having an old one for nearly 15 years....).

[Null 45 3,018]

4 hours ago, Kel9509 said:

I assume that those amounts are the same as included in the budget table (and updated the same way?).

They are the same as the budget window.

4 hours ago, Kel9509 said:

My new computer is coming along nicely though and I'm waiting for the motherboard to arrive before putting it together, hopefully next month.  Damn tariffs messed everything up, and it doesn't help that I'm an idiot and decided to build a top of the line system after having an old one for nearly 15 years....

I am planning to build a new machine, but the tariffs and limited supply on components such as cases and GPUs is making that difficult.

[Null 45 3,018]

Release version 1.0.1, which has the following changes:

• Fixed a bug where sc4game.budget.get_department_total_expense and sc4game.budget.get_department_total_income returned a string.
• Removed the print function from null45_lua_extensions.lua, this re-definition was turning the built-in Lua print function into a no-op for plugin scripts.

[Null 45 3,018]

Release version 1.1.0, which adds  a dbpf table with functions to read cohort/exemplar properties and check if specific TGI values exist.

[Null 45 3,018]

Release version 1.1.1, which made a number of functions that take hexadecimal ids easier to use by letting them read hexadecimal strings in addition to numbers.

The fact that APIs required the hexadecimal strings to be converted to numbers with hex2dec was easy to miss. Using sc4game.budget.get_department_total_income as an example:

Old code:

return tostring(sc4game.budget.get_department_total_income(hex2dec('a2963983')))

New code:

return tostring(sc4game.budget.get_department_total_income('a2963983'))

[Lab Rat 12]

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