sc4-park-and-ride-ordinance

A DLL Plugin for SimCity 4 that adds a Park and Ride ordinance to the game.

The ordinance allows the Park & Ride mode of the SimCity 4 traffic simulator to be enabled or disabled in-game. When the ordinance is enabled cars will be prevented from reaching their destinations, which requires Sims to use other forms of transit.

The mod automatically adjusts Travel type can reach destination property in the traffic simulator tuning exemplar. The second Boolean value of that property controls whether cars can reach their destination. See the Network Addon Mod Park and Ride documentation for more details on this property.

Technical Details

The mod works by loading the traffic simulator tuning exemplar and modifying the copy of the exemplar that the game temporarily caches in-memory. The DLL then sends a message to the traffic simulator that makes it read the new values from the cached exemplar.

System Requirements

• Windows 10 or later

The plugin may work on Windows 7 or later with the Microsoft Visual C++ 2022 x86 Redistribute installed, but I do not have the ability to test that.

Troubleshooting

The plugin should write a SC4ParknRideOrdinance.log file in the same folder as the plugin.
The log contains status information for the most recent run of the plugin.

License

This project is licensed under the terms of the MIT License.
See LICENSE.txt for more information.

3rd party code

gzcom-dll Located in the vendor folder, MIT License.
Windows Implementation Library MIT License

Source Code

Prerequisites

• Visual Studio 2022

Building the plugin

• Open the solution in the src folder
• Update the post build events to copy the build output to you SimCity 4 application plugins folder.
• Build the solution

Debugging the plugin

Visual Studio can be configured to launch SimCity 4 on the Debugging page of the project properties. I configured the debugger to launch the game in a window with the following command line:
-intro:off -CPUcount:1 -w -CustomResolution:enabled -r1920x1080x32

You may need to adjust the resolution for your screen.

Source Code Layout

ParknRideOrdinanceDllDirector.cpp is the main plugin file. It handles the setup that SC4 requires to load a DLL, and adding the ordinance into the game.

ParknRideOrdinance.h defines the methods that the ordinance overrides for its custom behavior.
ParknRideOrdinance.cpp provides the implementation for the methods that the ordinance overrides.

OrdinanceBase.cpp is the base class for ParknRideOrdinance. It handles the common logic for a custom ordinance. OrdinancePropertyHolder.cpp provides the game with a list of effects that should be applied when the ordinance is enabled. The effects can include Mayor Rating boosts, Demand boosts, etc.