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In this tutorial, we will create a simple mod that globally replaces vanilla road trees with custom trees made by MrMaison. Like in Tutorial 1, we will use a loading hook, prefab collections and the ModTools scene explorer. You will also learn how to add settings to your mod. Step 1: Exploring and modifying network and tree prefabs with the ModTools scene explorer Before writing the actual mod, we will apply the replacement with the ModTools scene explorer. Just like buildings, networks and trees are defined as prefabs (NetInfo and TreeInfo, see Tutorial 1 Step 3). There are various way to find these prefabs in the ModTools scene explorer. The easiest way that works for vanilla and workshop assets is the ToolsController. "Tools" in Cities: Skylines allow you to interact with the game world. The most obvious tool is the bulldozer, but there are also tools for the placement of objects, zoning, transport line creation and camera control. For this tutorial, we will access the TreeTool and the NetTool, which hold a reference to the tree/network prefab you are placing. Select a tree you in the Landscaping panel. I chose the Royal Palm made by MrMaison. While the placement mode is enabled, open the ModTools scene explorer (CTRL + E). On the left, select Tool Controller > TreeTool. You will see the properties of the TreeTool on the right. The currently selected tree prefab is stored in the m_prefab property. Press the "Copy" button to copy the reference of the tree prefab to the ModTools clipboard (it does not copy the actual data, just the memory address of the prefab). Tip: For every prefab (prop, building, network, ...) there is also a "Preview" button that displays a model viewer, and more importantly, a "Plop" button that allows you to plop the asset. With this button, you can place assets which are not available in the panels of the game, like props or sub-buildings. Now, select a road with trees in the Roads panel. I chose the "Large Avenue with Grass" that was added by the MT update. Open the scene explorer and select Tool Controller > NetTool. On the right, expand the m_prefab property (the currently selected network prefab). You can now see the properties of the network prefab. The structure of a network prefab looks like this: NetInfo: Network Prefab ├ m_nodes[]: Array of objects defining meshes/textures for intersections ├ m_segments[]: Array of objects defining meshes/textures for segments ├ m_lanes[]: Array of NetInfo.Lane objects │ └ NetInfo.Lane: Defines a lane used by vehicles or pedestrians + prop/tree decoration │ ├ m_laneProps │ │ └ m_props[]: Array of prop items │ │ └ NetLaneProps.Prop: Like BuildingInfo.Prop, defines the position a prop/tree │ │ ├ m_prop/m_finalProp: The prop prefab │ │ ├ m_tree/m_finalTree: The tree prefab │ │ ├ m_probability: Probability that the prop/tree spawns │ │ ├ m_repeatDistance: Distance between two props/trees │ │ └ ... │ └ ... └ ... Expand the m_lanes array and search for the lane that contains the tree prop items you want to replace. In case of the "Large Avenue with Grass", navigate to m_lanes > m_lanes.[0] > m_laneProps > m_props > m_props.[4]: Click the "Paste" button on the right for the properties m_finalTree and m_tree. This will assign the custom tree prefab we copied earlier to the prop item: You will instantly see the result: The trees of all avenues in the city have been replaced. In the next steps, we will create a mod that automates the replacement. Step 2: Project Setup Create a new project named "RoadTreeReplacer" in VS2017, following Method 2 in Tutorial 0 (working with a text editor is still possible in this tutorial, but not recommended) Your IUserMod implementation should look like this: using ICities; namespace RoadTreeReplacer { public class RoadTreeReplacerMod : IUserMod { public string Name => "Road Tree Replacer"; public string Description => "Replaces the boring Oak roadside trees with MrMaison's creations"; } } Step 3: Loading Hook & Tree Replacement Logic Create a new file called RoadTreeReplacerLoading.cs in the Solution Explorer. This file will contain our ILoadingExtension implementation that is invoked by the game when a save is loaded (See Tutorial 1 Step 2). Like in the last tutorial, we will use the static PrefabCollection class to find our network and tree prefab. Add the following contents to the file: using UnityEngine; using ICities; namespace RoadTreeReplacer { public class RoadTreeReplacerLoading : LoadingExtensionBase { public override void OnLevelLoaded(LoadMode mode) { // Find the network NetInfo netPrefab = PrefabCollection<NetInfo>.FindLoaded("Avenue Large With Grass"); // Find the tree we want to use as a replacement TreeInfo treePrefab = PrefabCollection<TreeInfo>.FindLoaded("909448182.Royal Palm_Data"); // Check if both prefabs are loaded, cancel if not if (netPrefab == null) { Debug.LogError("RTR: The network could not be found"); return; } if (treePrefab == null) { Debug.LogError("RTR: The replacement tree could not be found"); return; } // cancel if lanes array is null (networks without lanes) if (netPrefab.m_lanes == null) return; // iterate through all lanes foreach (NetInfo.Lane lane in netPrefab.m_lanes) { // cancel if lane props array is null (networks without lanes) if (lane?.m_laneProps?.m_props == null) continue; // iterate through all lane props of that lane foreach (NetLaneProps.Prop laneProp in lane.m_laneProps.m_props) { if (laneProp == null) continue; // if the tree/finalTree field is set, replace it with our tree prefab if (laneProp.m_tree != null) { laneProp.m_tree = treePrefab; } if (laneProp.m_finalTree != null) { laneProp.m_finalTree = treePrefab; } } } Debug.Log("RTR: Replacement successful!"); } } } Tip: You can use the Debug.Log(...) method to add log entries to the output_log.txt. The log entries are also displayed in the ModTools console, which can be used for debugging your mod. Now compile the mod (F6). If there are any compilation errors, use the error list in VS2017 to locate and fix the error (View > Error List) When the compilation was successful, run the game. Enable the mod in content manager (if your mod does not show up, you probably forgot to setup the post build script). Now create or load a city. The tree replacement is now automated. You will also see the success message in the ModTools console: Before we proceed with the next step, we will move our replacement code to a separate ReplaceNetTrees method. We can call this method multiple times with a single line of code: using UnityEngine; using ICities; namespace RoadTreeReplacer { public class RoadTreeReplacerLoading : LoadingExtensionBase { public override void OnLevelLoaded(LoadMode mode) { ReplaceNetTrees("Avenue Large With Grass", "909448182.Royal Palm_Data"); ReplaceNetTrees("Medium Road Decoration Trees", "909448182.Royal Palm_Data"); } private void ReplaceNetTrees(string netName, string treeName) { NetInfo netPrefab = PrefabCollection<NetInfo>.FindLoaded(netName); TreeInfo treePrefab = PrefabCollection<TreeInfo>.FindLoaded(treeName); if (netPrefab == null) { Debug.LogError($"RTR: The network {netName} could not be found"); return; } if (treePrefab == null) { Debug.LogError($"RTR: The replacement tree {treeName} could not be found"); return; } if (netPrefab.m_lanes == null) return; foreach (NetInfo.Lane lane in netPrefab.m_lanes) { if (lane?.m_laneProps?.m_props == null) continue; foreach (NetLaneProps.Prop laneProp in lane.m_laneProps.m_props) { if (laneProp == null) continue; if (laneProp.m_tree != null) laneProp.m_tree = treePrefab; if (laneProp.m_finalTree != null) laneProp.m_finalTree = treePrefab; } } Debug.Log($"RTR: Replacement of tree in network {netName} successful!"); } } } Step 4: Adding Mod Settings Right now the functionality of the mod is fixed, there is no way to configure which trees are replaced. Adding settings to a mod is a difficult task. It will require 3 components: User interface with checkboxes or dropdown menus (using the settings API provided by CO, or a custom window) Data structure for the settings data (usually a C# class, or a set of key-value pairs) Serialization System (to .xml file, or save game) To keep it simple, we will only add a simple settings page with 3 dropdown options (Small Road Tree, Medium Road Tree, Large Road Tree), with a fixed number of trees to choose from (Default, Royal Palm, Weeping Silver Birch, River Red Gum Small). The settings will saved in a .xml file in the Cities: Skylines installation directory. The settings are global, that means the mod applies the same settings to all cities (in one of the next tutorials, I will show you how to save additional data in the save game). Serialization System Add a new file called Configuration.cs and paste this code. It is a very minimalistic serialization library that I've written some time ago. It does all the heavy lifting for you (loading and saving of .xml files, transformation from/to C# objects). It is not important to understand what happens internally, you just have to understand how to use it. The library provides a method to load your configuration data: YourConfiguration config = Configuration<YourConfiguration>.Load(); And to save it: Configuration<YourConfiguration>.Save(); You only have to provide the data class that defines the structure of the .xml file. Note: If you are using a Mac, you may have to add the System.Xml dependency to your project Data Structure Add a new class named RoadTreeReplacerConfiguration. This data class contains the string options we want to save: namespace RoadTreeReplacer { [ConfigurationPath("RoadTreeReplacer.xml")] public class RoadTreeReplacerConfiguration { public string SmallRoadTree { get; set; } = "909448182.Royal Palm_Data"; public string MediumRoadTree { get; set; } = "909448182.Royal Palm_Data"; public string LargeRoadTree { get; set; } = "909448182.Royal Palm_Data"; } } The [ConfigurationPath] attribute is read by the serialization library. The strings on the right are the default values used when a new configuration is created. User Interface Some time ago, CO added a simple settings API that allows you to create simple setting menus with a few lines of code. To use it, add a new method called OnSettingsUI to your IUserMod implementation: using System; using System.Collections.Generic; using ICities; namespace RoadTreeReplacer { public class RoadTreeReplacerMod : IUserMod { public string Name => "Road Tree Replacer"; public string Description => "Replaces the boring Oak roadside trees with MrMaison's creations"; // The strings displayed in the dropdown private static readonly string[] OptionLabels = { "Default", "Royal Palm", "Weeping Silver Birch", "River Red Gum" }; // The corresponding prefab names private static readonly string[] OptionValues = { "Tree2Variant", "909448182.Royal Palm_Data", "765126845.Weeping Silver Birch_Data", "742114726.River Red Gum small_Data" }; // Sets up a settings user interface public void OnSettingsUI(UIHelperBase helper) { // Load the configuration RoadTreeReplacerConfiguration config = Configuration<RoadTreeReplacerConfiguration>.Load(); // Small Roads int smallSelectedIndex = GetSelectedOptionIndex(config.SmallRoadTree); helper.AddDropdown("Small Road Tree", OptionLabels, smallSelectedIndex, sel => { // Change config value and save config config.SmallRoadTree = OptionValues[sel]; Configuration<RoadTreeReplacerConfiguration>.Save(); }); // Medium Roads int mediumSelectedIndex = GetSelectedOptionIndex(config.MediumRoadTree); helper.AddDropdown("Medium Road Tree", OptionLabels, mediumSelectedIndex, sel => { // Change config value and save config config.MediumRoadTree = OptionValues[sel]; Configuration<RoadTreeReplacerConfiguration>.Save(); }); // Large Roads int largeSelectedIndex = GetSelectedOptionIndex(config.LargeRoadTree); helper.AddDropdown("Large Road Tree", OptionLabels, largeSelectedIndex, sel => { // Change config value and save config config.LargeRoadTree = OptionValues[sel]; Configuration<RoadTreeReplacerConfiguration>.Save(); }); } // Returns the index number of the option that is currently selected private int GetSelectedOptionIndex(string value) { int index = Array.IndexOf(OptionValues, value); if (index < 0) index = 0; return index; } } } What happens here? Load the config data with the Load method provided by the library Get the index of the dropdown option that should be selected at first Add a dropdown option with label, options, selected index and a callback (called when selection is changed) (Repeat 2. and 3. for medium and large roads) The OptionLabels array contains the strings displayed in the dropdown menus. The other array, OptionValues, contains the internal names of the prefabs. The callback is a lamda function that takes the selected index (0-3). It saves the value that corresponds to the selected index in the configuration file. The game automatically creates a settings page for mods which are implementing the OnSettingsUI method. No further steps are needed. Tip: Other methods for UI element generation: AddButton(), AddCheckbox(), AddGroup(), AddSlider(), AddSpace(), AddTextfield() Step 5: Using the configuration values in our loading hook In the RoadTreeReplacerLoading class, replace the OnLevelLoaded method: public override void OnLevelLoaded(LoadMode mode) { // Load the configuration RoadTreeReplacerConfiguration config = Configuration<RoadTreeReplacerConfiguration>.Load(); ReplaceNetTrees("Basic Road Decoration Trees", config.SmallRoadTree); ReplaceNetTrees("Oneway Road Decoration Trees", config.SmallRoadTree); ReplaceNetTrees("Medium Road Decoration Trees", config.MediumRoadTree); ReplaceNetTrees("Avenue Large With Grass", config.MediumRoadTree); ReplaceNetTrees("Avenue Large With Buslanes Grass", config.MediumRoadTree); ReplaceNetTrees("Large Road Decoration Trees", config.LargeRoadTree); ReplaceNetTrees("Large Oneway Decoration Trees", config.LargeRoadTree); } This will replace the trees of all vanilla roads with the trees selected in the settings. And we are done! After changing the options for the first time, the settings are saved to .xml: Note: To apply the changed settings, you have to reload your city. Happy Coding! Download Source Next part:

In this tutorial, we will create a basic mod in two different ways: With a simple text editor, and with the Visual Studio IDE. Cities: Skylines uses the Unity Engine, which is based on Mono, an open source implementation of the .NET framework that runs on Windows, Mac and Linux. That means the same code can be used on all of these platforms. The .NET framework is comparable to Java. It's basically a set of libraries and a virtual machine that runs your .NET applications. C# is the most common programming language that can be used to create .NET applications and libraries. It's very similar to Java (just better!). After writing your mod in C#, you have to compile it to create machine readable code. Cities: Skylines comes with an integrated compiler. It works like this: [.cs files containing raw C# code] → [COMPILER] → [compiled .dll file] The .dll file is your compiled mod (what you usually download from the Workshop). Alternatively, your can use an external compiler like the one provided by Visual Studio (see Method 2). Method 1: Using Notepad, let the game compile First we will create a mod with the tools provided by the game. The game searches for mod source folders in the directory C:\Users\<YourName>\AppData\Local\Colossal Order\Cities_Skylines\Addons\Mods. In this folder, create a new directory named "FirstMod". Inside of the new directory, create another folder named "Source". That's the directory for the .cs files Open Notepad (or your favourite text editor) and enter this code: // Makes UnityEngine and Cities: Skylines API classes available for use using ICities; using UnityEngine; // the namespace makes the names of your classes unique. // Naming: You can just use the name of your mod, it doesn't really matter. Spaces are not allowed. namespace Tutorial { // This defines a class that implements IUserMod. // The class defines the name and description displayed in the content manager. // The game searches for these classes. Every working mod must contain one class implementing IUserMod. // Naming: Just append "Mod" to the name of your mod, like "NetworkSkins" -> "NetworkSkinsMod". Spaces are not allowed. public class MyFirstMod : IUserMod { // this defines the title of your mod displayed in content manager public string Name { get { return "My First Mod"; } } // this defines the description of your mod displayed in content manager public string Description { get { return "Hello World, this is my first mod!"; } } } } (Lines starting with "//" are comments. You can add your own or remove them without affecting anything.) Save the file in the "Source" directory. Name it FirstMod.cs (in the file type dropdown, select "All Files"). Now just start your game. The game compiles your mod on start up. You will find it in the content manager: You will also notice a new .dll file in your mod directory. That's your compiled mod: So far we didn't add functionality to the mod. It only spawns the item in content manager. The big problem of Notepad and the game compiler is that it is hard to find errors in your code. You will have to restart your game many times. That's where Visual Studio comes into play... Method 2: Using Visual Studio (recommended) Visual Studio is a specialized IDE for C#/.NET development. It helps you to find errors in your code, and it autocompletes code statements for you, and it compiles your mod much faster than the game. It is also a requirement for advanced modding techniques like detours. The following tutorials will be based on Visual Studio. First of all, download and install Visual Studio Community 2017 for free. Make sure that the .NET desktop development feature is checked. Also enable the individual component .NET Framework 3.5 development tools. Step 1: Project Setup Create a new project in VS2017: Select File > New > Project On the left, select Templates > Visual C# > Windows Classic Desktop Select "Class Library (.NET Framework)" In the top, select ".NET Framework 3.5" in the dropdown menu (Important!) In the bottom, enter "SecondMod" as the name and solution name. and choose a location for your project files (e.g. your desktop) Press OK Visual Studio will create a project that looks like this: On the right, you can see the Solution Explorer with a list of .cs files. Visual Studio created a file named Class1.cs to get us started. If you want, you can rename the .cs file to match your mod name (Right click in solution explorer > Rename). Step 2: Dependencies Before we continue, we have to set up two things in the project. You always have to do it when you create a new mod project: First, we will add the modding API (ICities), UnityEngine, ColossalFramework and the game assembly (Assembly-CSharp) as dependencies. In the solution explorer, right click the "References" item and select "Add reference..."). Now use the "Browse..." button in the bottom to select the following .dll files. The files are located in the folder: Steam\steamapps\common\Cities_Skylines\Cities_Data\Managed Step 3: Post Build Script Secondly, we will add a so-called post build script: It automatically puts the compiled dll file into the C:SL mod directory when you compile with Visual Studio: Right-click your project in the Solution Explorer and choose Properties Select Build Events on the left hand side of the property sheet Paste the following in the Post-build event command line: mkdir "%LOCALAPPDATA%\Colossal Order\Cities_Skylines\Addons\Mods\$(SolutionName)" del "%LOCALAPPDATA%\Colossal Order\Cities_Skylines\Addons\Mods\$(SolutionName)\$(TargetFileName)" xcopy /y "$(TargetPath)" "%LOCALAPPDATA%\Colossal Order\Cities_Skylines\Addons\Mods\$(SolutionName)" Step 4: Writing the Mod Now we are finally ready for the creation of the actual mod. Replace the contents of Class1.cs with this code: using ICities; using UnityEngine; namespace Tutorial { public class MySecondMod : IUserMod { public string Name { get { return "My Second Mod"; } } public string Description { get { return "I made this with VS2017"; } } } } Step 5: Compilation Press F6 (or Build > Build Solution) to compile the mod. The mod should appear in your mod directory. Now start the game and enjoy the listing of your useless mod in content manager Happy Coding! Next part:

In this tutorial, we will replicate the functionality of the "Make Historical" checkbox in SimCity 4 (stop building from leveling up). The mod will utilize the same interfaces as the Control Building Level Up mod. You will learn how to inspect and modify user interfaces with ModTools, how the info panels of the game work, how to add a checkbox to the UI, how to control building level up with the official API, how to get notified when a building is added/removed and how to serialize custom data in the savegame. Once again, we will use the loading and threading hooks provided by the API. Step 1: Project Setup Create a new project named "MakeHistorical" in VS2017, following Method 2 in Tutorial 0 (working with a text editor is still possible in this tutorial, but not recommended) Your IUserMod implementation should look like this: using ICities; namespace MakeHistorical { public class MakeHistoricalMod : IUserMod { public string Name => "Make Historical"; public string Description => "Prevents the level up of buildings"; } } Step 2: Data Storage with Serialization Hook Data Structure We will store the ids (ushort) of the historical building instances in the savegame. Like in Tutorial 2 Step 4, we will create a data class that holds our data: using System.Collections.Generic; namespace MakeHistorical { public class MakeHistoricalData { public List<ushort> HistoricalBuildingIds { get; set; } = new List<ushort>(); } } The game requires additional savegame data to be in byte[] (byte array) format (basically zeros and ones, very low level). Luckily, Colossal Order provides a few useful tools to convert data classes to byte arrays (package ColossalFramework.IO). To use these tools, our data class must implement the IDataContainer interface. Extend the class like this: using System.Collections.Generic; using System.Linq; using ColossalFramework.IO; namespace MakeHistorical { public class MakeHistoricalData : IDataContainer { // The key for our data in the savegame public const string DataId = "MakeHistorical"; // Version of data save format // This is important when you add new fields to MakeHistoricalData public const int DataVersion = 0; public List<ushort> HistoricalBuildingIds { get; set; } = new List<ushort>(); // This serializes the object (to bytes) public void Serialize(DataSerializer s) { // convert ushort list to int array int[] ids = HistoricalBuildingIds.Select(id => (int)id).ToArray(); s.WriteInt32Array(ids); } // This reads the object (from bytes) public void Deserialize(DataSerializer s) { int[] ids = s.ReadInt32Array(); // convert int array to ushort list HistoricalBuildingIds = ids.Select(id => (ushort)id).ToList(); } // Validates that all building ids are active public void AfterDeserialize(DataSerializer s) { if (!BuildingManager.exists) return; List<ushort> validatedBuildingIds = new List<ushort>(); Building[] buildingInstances = BuildingManager.instance.m_buildings.m_buffer; // itertate through all building ids, filter active ids foreach (ushort buildingId in HistoricalBuildingIds) { if (buildingInstances[buildingId].m_flags != Building.Flags.None) { validatedBuildingIds.Add(buildingId); } } HistoricalBuildingIds = validatedBuildingIds; } } } What happened? We added the constants DataId and DataVersion. We will use these in the next step We implemented the Serialize method: In this method, we convert our list of ushort numbers to an integer array (the serializer does not support ushort) and pass it to a DataSerializer, which converts our array to bytes. We implemented the Deserialize method, which does the opposite of Serialize We implemented AfterDeserialize, which validates that all deserialized building ids belong to buildings (important when the mod was disabled for some time, to keep the data clean) Serialization System Colossal Order provides a serialization hook for mods (ISerializableDataExtension/SerializableDataExtensionBase). This hook is invoked when the savegame data is loaded, and when the user presses the save button. The game also provides a storage interface (ISerializableData) that allows us to write byte arrays to savegame and read byte arrays from savegame. Combined with the data class and the byte array conversion tools provided by Colossal Order, we will use this hook to save our data. Add a new MakeHistoricalDataManager class: using ColossalFramework.IO; using ICities; using System.IO; using UnityEngine; namespace MakeHistorical { public class MakeHistoricalDataManager : SerializableDataExtensionBase { // The data object of our mod private MakeHistoricalData _data; public override void OnLoadData() { // Get bytes from savegame byte[] bytes = serializableDataManager.LoadData(MakeHistoricalData.DataId); if (bytes != null) { // Convert the bytes to MakeHistoricalData object using (var stream = new MemoryStream(bytes)) { _data = DataSerializer.Deserialize<MakeHistoricalData>(stream, DataSerializer.Mode.Memory); } Debug.LogFormat("Data loaded (Size in bytes: {0})", bytes.Length); } else { _data = new MakeHistoricalData(); Debug.Log("Data created"); } } public override void OnSaveData() { byte[] bytes; // Convert the MakeHistoricalData object to bytes using (var stream = new MemoryStream()) { DataSerializer.Serialize(stream, DataSerializer.Mode.Memory, MakeHistoricalData.DataVersion, _data); bytes = stream.ToArray(); } // Save bytes in savegame serializableDataManager.SaveData(MakeHistoricalData.DataId, bytes); Debug.LogFormat("Data saved (Size in bytes: {0})", bytes.Length); } } } What happens here? The _data property stores our mod data The OnLoadData method attempts to read the saved byte array from the savegame. If the array was found, it converts the bytes to a MakeHistoricalData object (our data structure). If no array was found, it creates a new MakeHistoricalData object (new city or mod enabled for the first time). The OnSaveData method converts the MakeHistoricalData object to bytes, then saves the bytes in the savegame. Tip: To understand how data versioning works, look at this example data manager. Singleton To make the data readable from other classes, we will make MakeHistoricalDataManager implement a simple singleton pattern. We willl also add a few methods to lookup, add and remove building ids: // Singleton getter public static MakeHistoricalDataManager Instance { get; private set; } public bool IsHistorical(ushort buildingId) { return _data.HistoricalBuildingIds.Contains(buildingId); } public void AddBuildingId(ushort buildingId) { if (_data.HistoricalBuildingIds.Contains(buildingId)) return; _data.HistoricalBuildingIds.Add(buildingId); Debug.Log($"Historical Building {buildingId} added"); } public void RemoveBuildingId(ushort buildingId) { if (!_data.HistoricalBuildingIds.Contains(buildingId)) return; _data.HistoricalBuildingIds.Remove(buildingId); Debug.Log($"Historical Building {buildingId} removed"); } public override void OnCreated(ISerializableData serializedData) { base.OnCreated(serializedData); Instance = this; // initialize singleton } public override void OnReleased() { Instance = null; // reset singleton } Now we can use a simple statement to check if a building is historical: bool h = MakeHistoricalDataManager.Instance.IsHistorical(1234); Final code of the MakeHistoricalDataManager class. Step 3: Removing destroyed buildings from the list We have to remove buildings from the list when they are buldozed. Luckily CO added a hook just for that (not documented in the wiki): using ICities; using UnityEngine; namespace MakeHistorical { public class MakeHistoricalBuildingMonitor : BuildingExtensionBase { public override void OnBuildingReleased(ushort id) { if (MakeHistoricalDataManager.Instance.IsHistorical(id)) { // Remove demolished/destroyed buildings from the list of historical buildings MakeHistoricalDataManager.Instance.RemoveBuildingId(id); } } } } Tip: With the IBuildingExtension/BuildingExtensionBase hook, you can also manipulate which buildings are spawned, and there are hooks for building creation and relocation. Step 4: Inspecting And Manipulating User Interfaces with ModTools and ILSpy Like in SimCity 4, we will add a "Make Historical" checkbox to the building info window: To do that, we have to find out how to access the info window programmatically. ModTools supports us with its "debug view". You can toggle it with CTRL + R. Then move your mouse over the info panel (so that the tint of the panel changes to green) and press CTRL + F: The UI window component is now displayed in the ModTools scene explorer. The class name of the element is ZonedBuildingWorldInfoPanel. In the scene explorer, we can change properties like the colour, size and position of the window. We can also look at the child UI elements (buttons, text labels). The position of the child elements is determined by the relativeLayout property. Noted values: Height: 321 Left Padding: 14 (based on the child element positions) Bottom Padding: 27 (based on the child element positions) Now that we know the class name, we can locate the class in ILSpy to find out how to access it programmatically: ZonedBuildingWorldInfoPanel is a subclass of WorldInfoPanel, which contains a static Show<>() method: // WorldInfoPanel (taken from ILSpy) public static void Show<TPanel>(Vector3 worldMousePosition, InstanceID instanceID) where TPanel : WorldInfoPanel { TPanel tPanel = UIView.library.Show<TPanel>(typeof(TPanel).Name, false); tPanel.SetTarget(worldMousePosition, instanceID); tPanel.component.opacity = 1f; } After further investigation (use ILSpy's "Analyze" feature), you will find a Get<>() method in UIView.library which returns the ZonedBuildingWorldInfoPanel instance: var panel = UIView.library.Get<ZonedBuildingWorldInfoPanel>(typeof(ZonedBuildingWorldInfoPanel).Name); Note: There is only one panel instance, which is just filled with the data of the currently selected building. The panel even exists when no building is selected, it's just hidden. Step 5: Adding a Checkbox to the Info Panel Finding the right property values for user interfaces is a finicky task, especially when you have to restart the game after every little change. Using the ModTools console, we can add and modify our checkbox while the game is running. Run this script in the ModTools console (F7): var panel = UIView.library.Get<ZonedBuildingWorldInfoPanel>(typeof(ZonedBuildingWorldInfoPanel).Name); var checkBox = panel.component.AddUIComponent<UICheckBox>(); checkBox.width = panel.component.width; checkBox.height = 20f; checkBox.clipChildren = true; UISprite sprite = checkBox.AddUIComponent<UISprite>(); sprite.spriteName = "ToggleBase"; sprite.size = new Vector2(16f, 16f); sprite.relativePosition = Vector3.zero; checkBox.checkedBoxObject = sprite.AddUIComponent<UISprite>(); ((UISprite)checkBox.checkedBoxObject).spriteName = "ToggleBaseFocused"; checkBox.checkedBoxObject.size = new Vector2(16f, 16f); checkBox.checkedBoxObject.relativePosition = Vector3.zero; checkBox.label = checkBox.AddUIComponent<UILabel>(); checkBox.label.text = " "; checkBox.label.textScale = 0.9f; checkBox.label.relativePosition = new Vector3(22f, 2f); checkBox.name = "MakeHistorical"; checkBox.text = "Make Historical"; This will add everything that is required for a checkbox, giving it the name "MakeHistorical". It is still in the wrong position: Tip: SamsamTS created a very useful utility class that allows you to create various UI elements. The code above was copied from that class. With ModTools, we can experiment with the position without restarting the game. Execute this code in the ModTools console: var panel = UIView.library.Get<ZonedBuildingWorldInfoPanel>(typeof(ZonedBuildingWorldInfoPanel).Name); var checkBox = panel.component.Find<UICheckBox>("MakeHistorical"); checkBox.relativePosition = new Vector3(14f, 164f + 130f + 5f); Result: Now we just have to increase the height of the window a little bit. Execute this code in the ModTools console: var panel = UIView.library.Get<ZonedBuildingWorldInfoPanel>(typeof(ZonedBuildingWorldInfoPanel).Name); panel.component.height = 321f + 5f + 20f; Result: Now, we will put the code we just executed with the console into the loading hook of our mod: using ColossalFramework.UI; using ICities; using UnityEngine; namespace MakeHistorical { public class MakeHistoricalLoading : LoadingExtensionBase { private UICheckBox _makeHistoricalCheckBox; public override void OnLevelLoaded(LoadMode mode) { if (_makeHistoricalCheckBox != null) return; ZonedBuildingWorldInfoPanel panel = UIView.library.Get<ZonedBuildingWorldInfoPanel>(typeof(ZonedBuildingWorldInfoPanel).Name); UICheckBox checkBox = panel.component.AddUIComponent<UICheckBox>(); checkBox.width = panel.component.width; checkBox.height = 20f; checkBox.clipChildren = true; UISprite sprite = checkBox.AddUIComponent<UISprite>(); sprite.spriteName = "ToggleBase"; sprite.size = new Vector2(16f, 16f); sprite.relativePosition = Vector3.zero; checkBox.checkedBoxObject = sprite.AddUIComponent<UISprite>(); ((UISprite)checkBox.checkedBoxObject).spriteName = "ToggleBaseFocused"; checkBox.checkedBoxObject.size = new Vector2(16f, 16f); checkBox.checkedBoxObject.relativePosition = Vector3.zero; checkBox.label = checkBox.AddUIComponent<UILabel>(); checkBox.label.text = " "; checkBox.label.textScale = 0.9f; checkBox.label.relativePosition = new Vector3(22f, 2f); checkBox.name = "MakeHistorical"; checkBox.text = "Make Historical"; checkBox.relativePosition = new Vector3(14f, 164f + 130f + 5f); panel.component.height = 321f + 5f + 16f; _makeHistoricalCheckBox = checkBox; } } } Compile the mod (F6). If there are any compilation errors, use the error list in VS2017 to locate and fix the error (View > Error List) When the compilation was successful, run the game. Enable the mod in content manager (if your mod does not show up, you probably forgot to setup the post build script). Now create or load a city, open the building info window for a growable building. Et voila: Step 6: Processing Checkbox Events To process checkbox events, we will add a delegate to the CheckedChange event: public override void OnLevelLoaded(LoadMode mode) { ... checkBox.eventCheckChanged += (component, check) => { ushort buildingId = WorldInfoPanel.GetCurrentInstanceID().Building; if (check) { MakeHistoricalDataManager.Instance.AddBuildingId(buildingId); } else { MakeHistoricalDataManager.Instance.RemoveBuildingId(buildingId); } }; } Clicking the checkbox now triggers the data manager: Step 7: Monitoring the ZonedBuildingWorldInfoPanel with a Threading Hook There is another problem: The checkbox is not updated when you select a building. We will use a threading hook to update the checkbox: using ColossalFramework.UI; using ICities; namespace MakeHistorical { public class MakeHistoricalPanelMonitor : ThreadingExtensionBase { private ZonedBuildingWorldInfoPanel _panel; private UICheckBox _makeHistoricalCheckBox; private ushort _lastBuildingId = 0; // called every frame public override void OnUpdate(float realTimeDelta, float simulationTimeDelta) { if (!FindComponents()) return; if (_panel.component.isVisible) { ushort buildingId = WorldInfoPanel.GetCurrentInstanceID().Building; if (_lastBuildingId != buildingId) { // display the right checkbox state _makeHistoricalCheckBox.isChecked = MakeHistoricalDataManager.Instance.IsHistorical(buildingId); _lastBuildingId = buildingId; } } else { _lastBuildingId = 0; } } private bool FindComponents() { if (_panel != null && _makeHistoricalCheckBox != null) return true; _panel = UIView.library.Get<ZonedBuildingWorldInfoPanel>(typeof(ZonedBuildingWorldInfoPanel).Name); if (_panel == null) return false; _makeHistoricalCheckBox = _panel.component.Find<UICheckBox>("MakeHistorical"); return _makeHistoricalCheckBox != null; } } } Step 8: Controlling Building Level Up It took quite some time to get to this point (UI and serialization are always very time consuming). The last missing piece is the ILevelUpExtension/LevelUpExtensionBase hook, which monitors and manipulates the level up behaviour of buildings. Probably the least complicated part of the mod: using ICities; namespace MakeHistorical { public class MakeHistoricalLevelUpMonitor : LevelUpExtensionBase { public override ResidentialLevelUp OnCalculateResidentialLevelUp(ResidentialLevelUp levelUp, int averageEducation, int landValue, ushort buildingID, Service service, SubService subService, Level currentLevel) { if (MakeHistoricalDataManager.Instance.IsHistorical(buildingID)) { levelUp.targetLevel = currentLevel; } return levelUp; } public override CommercialLevelUp OnCalculateCommercialLevelUp(CommercialLevelUp levelUp, int averageWealth, int landValue, ushort buildingID, Service service, SubService subService, Level currentLevel) { if (MakeHistoricalDataManager.Instance.IsHistorical(buildingID)) { levelUp.targetLevel = currentLevel; } return levelUp; } public override IndustrialLevelUp OnCalculateIndustrialLevelUp(IndustrialLevelUp levelUp, int averageEducation, int serviceScore, ushort buildingID, Service service, SubService subService, Level currentLevel) { if (MakeHistoricalDataManager.Instance.IsHistorical(buildingID)) { levelUp.targetLevel = currentLevel; } return levelUp; } public override OfficeLevelUp OnCalculateOfficeLevelUp(OfficeLevelUp levelUp, int averageEducation, int serviceScore, ushort buildingID, Service service, SubService subService, Level currentLevel) { if (MakeHistoricalDataManager.Instance.IsHistorical(buildingID)) { levelUp.targetLevel = currentLevel; } return levelUp; } } } The logic is very simple: When the building is historical, the target level is set to the current building level. And we are done! Buildings with the "Make Historical" checkbox enabled will no longer level up. The list of historical buildings is stored in the savegame. Happy Coding! Download Source

In this tutorial, we will create a simple mod that removes some of the ugly vanilla billboard props. You will learn how to work with loading hooks, prefab collections and the ModTools scene explorer. Step 1: Project Setup Create a new project named "CityBeautifier" in VS2017, following Method 2 in Tutorial 0 (working with a text editor is still possible in this tutorial, but not recommended) Your IUserMod implementation should look like this: using ICities; namespace CityBeautifier { public class CityBeautifierMod : IUserMod { public string Name => "City Beautifier"; public string Description => "Removes some ugly props"; } } Tip: The arrow syntax (=>) is a shorthand for the property syntax (get { return ...; }) used in the 0. tutorial. Both are equivalent. Step 2: Loading Hook The Mod API of Cities: Skylines contains various extension interfaces. You can create classes implementing these interfaces to hook into the game. The most important interface is ILoadingExtension. A class implementing this interface will get notified when the loading process begins and when it completes, and when a save is unloaded. Create a new file called CityBeautifierLoading.cs in the Solution Explorer. Add the following content to the file: using ColossalFramework.UI; using ICities; namespace CityBeautifier { public class CityBeautifierLoading : ILoadingExtension { // called when level loading begins public void OnCreated(ILoading loading) { } // called when level is loaded public void OnLevelLoaded(LoadMode mode) { // create dialog panel ExceptionPanel panel = UIView.library.ShowModal<ExceptionPanel>("ExceptionPanel"); // display a message for the user in the panel panel.SetMessage("City Beautifier", "The level is loaded!", false); } // called when unloading begins public void OnLevelUnloading() { } // called when unloading finished public void OnReleased() { } } } Tip: You can also extend the class LoadingExtensionBase. It allows you to override a single loading method instead of implementing all methods Now compile the mod (F6). If there are any compilation errors, use the error list in VS2017 to locate and fix the error (View > Error List) When the compilation was successful, run the game. Enable the mod in content manager (if your mod does not show up, you probably forgot to setup the post build script). Now create or load a city. You will see the dialog panel as soon as the loading screen disappears: Close the game (UI development requires a complete restart after every change) Step 3: Working with the Prefab Collection Our goal is the removal of various props which are attached to buildings. To do that, we have to access the collection of loaded buildings, more specifically building prefabs. Prefabs vs. Instances: Building prefabs are templates for building instances. That means when a building instance is spawned, it uses the properties, textures and models defined in the building prefab. Modifying the building prefab usually causes all building instances to change. There are also prefabs for trees, props, vehicles and networks. Prefab classes of the game always end with Info (e.g. BuildingInfo, PropInfo, ...). All building prefabs can be found in the PrefabCollection<BuildingInfo>. We will now learn how to cycle through all buildings in this collection. Replace the OnLevelLoadedMethod with this code, then compile the mod and run the game: public void OnLevelLoaded(LoadMode mode) { // total number of loaded building assets int buildingPrefabCount = PrefabCollection<BuildingInfo>.LoadedCount(); // create a message string for the user string message = "Number of building assets: " + buildingPrefabCount; // create dialog panel ExceptionPanel panel = UIView.library.ShowModal<ExceptionPanel>("ExceptionPanel"); // display the message in the panel panel.SetMessage("City Beautifier", message, false); } This will output the total number of loaded building prefabs: Now we will create a list of all building names, using a simple for loop. The LoadedCount() method returns the total number of prefabs. We can use the GetLoaded(uint) method to get the prefab objects, using a number in range 0 <= index < buildingPrefabCount: public void OnLevelLoaded(LoadMode mode) { int buildingPrefabCount = PrefabCollection<BuildingInfo>.LoadedCount(); string message = "Number of building assets: " + buildingPrefabCount; // append a list of building names to the message for(uint index = 0; index < buildingPrefabCount; index++) { // get the building asset with the given index from the collection BuildingInfo prefab = PrefabCollection<BuildingInfo>.GetLoaded(index); // append a separator and the name of the asset to the message message += ", "; message += prefab.name; } ExceptionPanel panel = UIView.library.ShowModal<ExceptionPanel>("ExceptionPanel"); panel.SetMessage("City Beautifier", message, false); } The output looks like this: We learned how to access the building prefabs. In the next step, we will use ModTools to dive deeper into the structure of BuildingInfo objects. Step 4: Exploring and modifying building prefabs with the ModTools scene explorer Subscribe to ModTools and enable the mod in content manager. Create or load a city and click on a building you want to inspect. Then use the "Find in Scene Explorer" button. I picked one of the commercial buildings that is decorated with ugly billboards: The properties displayed in the scene explorer belong to the building instance. Props are defined in the building prefab. Luckily the prefab can be found right at the top (expand the "Info" property). Scroll down and expand the "m_props" property. You will see a list of prop items: Expand the items of the list to find out more about the props. Here you can change properties like position, probability and angle. Find the prop you want to remove and set the probability to 0: The prop will disappear instantly. Repeat the step for all props you want remove. Create a list of all prop names, like this: Billboard_big_variation_02 Billboard_big_variation_04 neon-yakisoba-noodles neon-burned-bean-coffee neon-morellos Billboard_big_variation Billboard_big_variation_01 Problem: The changes you applied to the prefabs are not permanent because prefabs are loaded from game/.crp files when you load your city. In the next step, we will change the probability values programmatically, in the loading class of our mod. Step 5: Modify building props programmatically We will remove the panel/message used in Step 3. Instead, we will add another nested for loop to cycle through all prop items of every building prefab: public void OnLevelLoaded(LoadMode mode) { for(uint index = 0; index < PrefabCollection<BuildingInfo>.LoadedCount(); index++) { // get the building prefab with the given index from the collection BuildingInfo prefab = PrefabCollection<BuildingInfo>.GetLoaded(index); // skip prefabs without props if(prefab == null || prefab.m_props == null) continue; for (int propIndex = 0; propIndex < prefab.m_props.Length; propIndex++) { // get the prop item BuildingInfo.Prop propItem = prefab.m_props[propIndex]; // skip trees/undefined props etc. if (propItem.m_prop == null) continue; string propName = propItem.m_prop.name; // check if the prop name equals one of the banned props if (propName == "Billboard_big_variation" || propName == "Billboard_big_variation_01" || propName == "Billboard_big_variation_02" || propName == "Billboard_big_variation_04" || propName == "neon-yakisoba-noodles" || propName == "neon-burned-bean-coffee" || propName == "neon-morellos") { // set the probability to zero to hide the props propItem.m_probability = 0; } } } } The continue keyword is a control statement of the for loop. It skips the execution of the current iteration and moves along to the next iteration of the loop. Tip: Instead of using the equals operator (==), you can use the Contains method to detect all prop names containing a certain string: if (propName.Contains("Billboard_big") || propName.Contains("neon-")) { propItem.m_probability = 0; } The result (before-after): You can see that the mod removes the billboards from all buildings. We reached our goal! Happy Coding! Tip: You can also remove trees with the same technique: if (propItem.m_tree == null) continue; string treeName = propItem.m_tree.name; Tip: You can limit the replacement to buildings with a certain name, or buildings of certain zone type: for(uint index = 0; index < PrefabCollection<BuildingInfo>.LoadedCount(); index++) { BuildingInfo prefab = PrefabCollection<BuildingInfo>.GetLoaded(index); if(prefab == null || prefab.m_props == null) continue; // filter by name if(!prefab.name.Contains("Blockhouse")) continue; // filter by building/service type if (prefab.m_class.m_service != ItemClass.Service.Industrial) continue; // ... } Next part:

I found this to be very interesting. It features many interesting modeling techniques and blender shortcuts, even texture baking from different raw materials. The only thing that it does not teach is how to save space on the uv map, by overlaying similar faces, and how to make a LOD.

Today I inspected the zoning code of the game. It seems like the original plan of the developers were 8 cell deep zones. All of the data structures were made for that. That means it might be possible to increase the maximum growable size to 8x8! I'm currently trying to decrypt the decompiled code (which misses hints, comments and variable names). So far everything looks good, I understand what it does and which passages have to be changed. Here is a screenshot of a test: In the debug window you can see the output of a test script. It displays the "valid mask" of the zone block you see. A zone block has a max width of 8 cells and a max depth of 8 cells (though only 4 are being used). When you draw a pedestrian path on a cell, it is marked as "invalid" (0) as well as all cells behind it (that's why there are 5 zeros in a row).

Network Skins 2 is coming soon! It's a complete redevelopment of version 1 with a lot of new features and a brand new GUI developed by @TPB. Features (everything listed can be adjusted per none/segment): Road Tree replacement Streelight replacement Pillar replacement Pavement color Ground texture (concrete, gravel, ruined, none, this is the sidewalk on normal roads) Rail catenaries and wires Remove road decorations Remove zebra crossings There will also be an advanced mode that allows you to apply any kind of modification to network segments and props (like the addition of trees and lights to networks which don't have them, the removal of segment meshes, the addition or removal of any kind of prop. Preview of the new GUI (icons not final):

A few updates were released for NS2, including bug fixes and new functionality. It is now very stable and will soon replace NS1!

Click on "Show in scene explorer", expand "Info", expand "m_subBuildings", expand "m_buildingInfo" of one of the sub-buildings. In there you get "m_mesh" and "m_material" and you can dump them, maybe there is also a button to dump everything.

It can be modified and there are many ways to do so. I guess there is not that much interest.

Sorry for the late reply. The OutsideConnectionAI (a building) is sending out transfer offers, incoming and outgoing (one is export, one import). Buildings also sent out offers. When 2 offers are matching, a truck is spawned, then ModifyMaterialBuffer is called on the building, and the vehicle route is calculated. Then the vehicle goes to outside connection (on export) or to the building (on import).

Are you actually talking about AO or normal maps? Because you could use a normal map to add extra details.

Hey! One thing you might want to look at is MoveIt! Export/Import function. it also uses xml and places down large amounts of networks. I think regarding the terrain, 1081 is just the resolution it has and there is no way to make it more detailed. I guess you could just write your own extension methods that replicate LINQ. Not sure if it is possible to use it.

not sure what you mean. You can for sure export sub-building meshes and materials.

This is really cool!

After a lot of trial and error, I was able to add mesh animations to a building asset. I created a "Custom Animation Loader (CAL)" mod that loads these custom animations for your building assets! The animations are created in Blender (you can also preview them there), then imported into the Unity Editor, where the animation logic is created with a visual editor, then exported as Unity asset bundles. The bundles are then loaded by a mod and applied to a normal .crp asset on level load. The mod is now out on the workshop: https://steamcommunity.com/sharedfiles/filedetails/?id=1664509314 A first asset made by Quad: https://steamcommunity.com/sharedfiles/filedetails/?id=1664515690 Resources for asset creators: written guide made by Ronyx: http://cslmodding.info/mod/custom-animation-loader/ I created a video that shows the asset creation workflow. The mod is ready, you can the tutorial files on the STEX. It supports buildings with bone animations. Future Plans It seems like it is possible to animate all kinds of assets. Buildings, vehicles, props, citizens... Going further, it's also possible to add custom AIs that control the animation parameters, for things like boom barriers, drawbridges, crowds of people, floodgates, harbour cranes, buses with door animations and all that stuff. Animations can have complex logic and transitions and multiple different states. Animation and Bones in Blender: Animator Controller setup in Unity:

Ali, the creator of the market stalls, just told me that he used a kinect sensor to record motion captures.

It's a difficult topic that requires more investigation. I would say it's definitely possible, but not a beginner task. Looking at the source code with ILspy, especially the AI of the stadiums and the event manager.

Cool stuff! Maybe there are open source motion tracking files or something like that.

New week, new mod! This one allows you to increase the LOD render distance of trees, buildings and networks! Very nice in combination with Random Tree Rotation, or isometric view... It is much more advanced (further distance), much more performant and more configurable than the old LOD Toggler. https://steamcommunity.com/sharedfiles/filedetails/?id=1680642819

Decal render distance option is now available

Wow, those look excellent! The slopes are so smooth! Just a tip, you can hide the user interface by pressing the little camera button in the bottom right.

https://docs.google.com/spreadsheets/d/1mVFkj_7ij4FLzKs2QJaONNmb9Z-SRqUeG6xFGqEX1ew/view#gid=1838874458https://docs.google.com/spreadsheets/d/1mVFkj_7ij4FLzKs2QJaONNmb9Z-SRqUeG6xFGqEX1ew/view#gid=1838874458

Actually there is only one kind of "sick". When the "health" value I mentioned is too low (because you didn't build a hospital, because of pollution or garbage piles, because of high crime rate etc.), people get sick. I have now investigated a bit further. There are 3 types of problem icons that can appear above a building: DirtyWater Pollution Noise Then there is also the "Death" icon. These icons generally appear when no ambulance or hearse arrives within a certain time frame (32 or 64 building ticks). The icons become red ("Major problem") after 96 or 128 ticks. Are you sure that you are playing the game without mods? Do you have a deathcare system? When people get sick, there is also always a chance that they die. The algorithm works like this: The game calculates a "sickness chance" (0-100) and a "bad health" value (0-3) that depends on the "health" value (0-100) that I explained in my last post, as well as the healthcare availability: If the health value is <= 10: If "bad health" is below 3, increase by 1 and set the sickness chance to 15 Else if "bad health" is 3: If there is no healthcare coverage, set the sickness chance to 75 Else set the sickness chance to 50 If the health value is <= 25: Set the sickness chance to 10 and reset "bad health" to 0 Else set the sickness chance to 0 and reset "bad health" to 0 In the next step a random number (0-100) is generated. If the number is smaller than "sickness chance", the citizen becomes sick. After that, if the citizen became sick, another random number is generated and there is a 1/3 chance that a citizen dies. When the citizen died, there is a 50% chance that their body magically disappears (cannibals???), otherwise a hearse is called. The only chance for citizens to get well again is a hospital visit. When a citizen is sick but the healthcare coverage improved or the cause of the sickness has been eliminated (higher "health" value), there is no longer a chance that they die, but they will be sick until an ambulance arrives.

The code for citizen health can be found in a single method: ResidentAI.UpdateHealth Currently citizen health (1 to 100) is affected by: Age and education (children and seniors have a very high healthcare requirement) Garbage amount Noise Pollution (eco residential is more sensitive) Ground Pollution (eco residential is more sensitive) Crime Rate Water/Sewage availability Health service coverage Various city policies When the health level is below 50, there is a chance that a citizen slowly becomes sick (there are 4 levels of bad health/sickness) or dies (lower health level increases the chance significantly). If the health level is above 50, the citizen will live a happy life until he is between 240 and 255 ticks old. --- It must be noted that "bad health" and "sick" citizen will cause the display of a warning icon above their home, usually displaying the cause of the sickness. If you spend a lot on healthcare, cims don't get sick and there is zero chance of an early death. IMHO the current logic isn't that bad, maybe a bit idealistic. Don't forget that this is a game that is meant to be fun and easy to understand. Of course it is possible to edit or replace ResidentAI.UpdateHealth if we wanted to What I would like to see is some kind of pandemy mod where a virus spreads throughout your city. That would be an interesting challenge.