Contents

• Introduction
  • Sample 0 A.D. Class Experience
  • Lesson Background
  • Learning Outcomes
  • Requirements
    • 0 A.D.: Basic Installation
    • 0 A.D.: Advanced Installation and Setup Notes
    • Image Editing Software (GIMP or other)
• What is 0 A.D.?
  • A Scholarship-aware Community Endeavor
  • Linguistic Practice and Contribution
• Customizing 0 A.D. for Educational Use
  • Automatically Installing Community Gameplay Modifications
    • Two Recommended Mods
      • Manual Mod Installation
  • Next Steps with Community Mods
• Importing Geographic Data to Create Historical Scenarios
  • 1. Choose a Scenario
  • 2. Find a Topographic Map
  • 3. Modify the Topographic Map Image
  • 4. Import the Topographic Map Image into Atlas
  • 5. Add, Adjust, and Smoothen the Terrain’s Features
  • 6. Add Flora and Fauna to the Terrain
  • 7. Add Scenario-specific Features
  • 8. Save the scenario, and distribute it.
  • 9. Play the scenario.
• Beyond? Join the Community, Build a Modification from Scratch, and More
  • Endnotes

Introduction

0 A.D.: Empires Ascendant is a cross-platform, scholarship-aware, and fully free and open source singleplayer and multiplayer historical real-time strategy (RTS) computer game of ancient civilization building and warfare making that has been under continuous development since 2001. 0 A.D. stands alone as an entirely customizable digital game that is built with real ancient history as one of its guiding principles. It even includes reconstructed, pre-modern languages in both written and spoken forms. 0 A.D. is an ideal software platform for team-based history and language instruction.

In this intermediate-level Programming Historian lesson, I presume some experience with installing software and playing computer games. As you progress, you will learn how to use the hackable sandbox that is 0 A.D. to help you teach history and languages. Since your students will need some onboarding with 0 A.D., it is advisable to implement the ideas that are contained in this tutorial during contexts in which you and your students are able to learn side-by-side.

This tutorial should be fitting for you if you are a secondary or postsecondary instructor of materials connected with any of the following topics related to the pre-modern world, as well as for anyone looking to integrate gaming into your adult education:

• classics and/or ancient history
• biblical studies
• medieval studies
• ancient archaeology
• ancient languages

In the example that I have assembled for this tutorial, I recreate one of Julius Caesar’s famous battles during the Gallic Wars. Yet, you may choose to follow the tutorial to build a special scenario for your own class from a variety of ancient civilizations across Eurasia, Africa, and the Americas.

Sample 0 A.D. Class Experience

After starting a new game, in the role of an ancient civilization’s controller, you and your few starting units, who are humbly in the early Village Phase of development with few technologies available, find yourselves isolated from the rest of the world. The game puts you in a position where you are unable to interact with anything beyond the small parcel of land that you control until you have sent scouts to explore beyond your territory. You must scramble to gather resources for building houses, farms, and barracks, as well as food, using the technologies that the civilization that you have chosen actually possessed in antiquity.

Gradually, you coordinate with your allies – this computer game, 0 A.D, is best enjoyed in multiplayer modes – to build a sophisticated trade network, advancing first to the Town Phase and then, eventually, the mighty City Phase. By researching historically accurate technologies and constructing many true-to-life buildings, your civilization becomes capable of creating an ever more sophisticated economy and ever more capable war machine. Each civilization has its own realistic economic and militaristic advantages and disadvantages that you must collaboratively exploit with your allies in order to defeat your enemies, ultimately achieving shared control over the entire geographic region.

While you progress toward the goal of regional control, you learn a great deal about the economies, militaries, and languages of the civilizations that are part of your match – possibly even more than you would learn with the same amount of time spent doing traditional classwork.

Lesson Background

For the last two weeks of the spring semester of 2023, I brought 0 A.D. into my own university-level Classical and New Testament Greek class. My objective was to use the game as a tool for team building, historical study, and linguistic practice. This tutorial is based on that androgogical trial, as well as my hundreds of hours of first-hand experience interacting with the software.

As Sylvester Arnab, Samantha Clarke, and Luca Morini write in their 2019 article “Co‑Creativity through Play and Game Design Thinking,” “students discover the importance of elements such as empathy, purpose, meaning, art, creativity, and teamwork in their [game-based] learning regardless of the specific disciplines they are pursuing.”¹ If creativity is found at the intersection of apparently disconnected subjects, then it would be challenging to think of a more creative partner for secondary or postsecondary education than cooperative real-time strategy (RTS) gaming design and gameplay.

Learning Outcomes

By the end of this tutorial, you will learn:

• what the 0 A.D. community project is, how to use its documentation, and why it may be said that the game that the project team produces is well-rooted in history and linguistics
• the basic methods with which you might use 0 A.D. inside a history or language class for productive group study
• the simple customization options that are available for 0 A.D.’s use in the classroom, including community-made gameplay modifications
• how to build your own realistic historical scenario by importing real-world topography and crafting a playable scene atop it
• how to begin drafting your own stand-alone 0 A.D. gameplay modification

Requirements

This Programming Historian tutorial is structured so that you only need to have basic familiarity with real-time strategy (RTS) gaming and image editing in order to complete it. For advanced work based on later portions of the tutorial, some familiarity with computer coding would be helpful. Yet, no programming knowledge is required for the tutorial as a whole.

0 A.D.’s complete user interface (UI) is available in many modern languages, including all four of the Programming Historian’s (English, Spanish, French, and Portuguese), and its gameplay features several ancient languages, such as Latin and Classical Greek.

0 A.D.: Basic Installation

0 A.D. is accessible by community members on every major desktop operating system (OS).² For Apple MacOS or Microsoft Windows, the best place to find an installable package is on the 0 A.D. website’s Download page. For a libre Unix-like OS (such as GNU/Linux or a *BSD), the best place to find an installable package of the game is the OS’s own package repository.

0 A.D.: Advanced Installation and Setup Notes

Per the official minimum hardware requirements for 0 A.D., the game should run on a majority of 32-bit or 64-bit x86 computer systems that are in operation for home and/or office use today, and the game is able to be compiled on ARM.³

Users of Unix-like OSes may elect to compile the game from source.

For multiplayer testing and/or gameplay, whether over a Local Area Network (LAN) or the Wide Area Network (WAN, “Internet”), it is best practice to have all players on wired network connections (rather than wireless/WiFi). Doing so reduces the risk of packet drops causing game stutters and/or crashes. If students should be using laptop computers rather than desktop machines (e.g. in a computer lab), simple USB to RJ-45 (“Ethernet”) adapters can faciliate easy wired networking. Otherwise, if the wireless network itself is stable, wireless networking may suffice (I have fallen back on this arrangement with students successfully myself).

Image Editing Software (GIMP or other)

In this lesson, you will learn to use the free and open source GNU Image Manipulation Program (GIMP) to model the image editing necessary to prepare real-world topographical data for import into 0 A.D. If you already know how to use another image editing program (such as Adobe Photoshop), then you ought to use that instead, replacing the lesson’s steps for working in GIMP with the equivalents in the program of your choosing.

Like 0 A.D., GIMP is available for every major desktop OS. For Apple MacOS or Microsoft Windows, the best place to find an installable package is on the official GIMP website’s Downloads page. For a libre Unix-like OS (such as GNU/Linux or a *BSD), the officially recommended way to install GIMP is via the OS’s own package repository.

GIMP has modest hardware requirements (lower than 0 A.D.).[^4]

What is 0 A.D.?

The 0 A.D. project was formed by the partnership of at least three computer gaming communities who were separately making gameplay modifications (mods) for Ensemble Studios’ famous Age of Empires (1997) and Age of Empires II (1999) RTS games. Age of Empires II in particular was instrumental in defining the multiplayer RTS genre, serving as a standby of LAN parties for many years and frequenting many major publications’ lists of the best/greatest video games of all time. Modifying this title, such as by incorporating new civilizations, has been popular from its launch.

Through interactions on the long-running Age of Kings Heaven Forums, a discussion zone for fans of the Age of Empires games, the members of the three communities decided to collaborate to create a wholly new game that would be historically and strategically richer than they had found to be possible by modifying the Age of Empires titles.

One of the three founding groups was called Wildfire Studios. The three teams decided to adopt the name “Wildfire Games” for the umbrella organization that they formed together circa 2002. Wildfire Games now oversees not only the [Rome at War])(https://wildfiregames.com/raw/) overhaul modification for Age of Empires II: The Age of Kings that was the claim to fame of the original Wildfire Studios, but also Pyrogenesis, the built-from-scratch game engine behind 0 A.D., as well as the 0 A.D. project as a whole.

Since the 0 A.D. project was founded by gameplay modifiers, modification always has been a normal part of the playerbase’s engagement with it. Yet, it was not until 2009 that the project leaders decided to make the game’s source code public under libre licenses. Opening the source code seems to have allowed the project to progress at a more efficient pace than it had in its earliest years. Furthermore, that decision has made possible both the large number of mods that are available for 0 A.D. and 0 A.D.’s rare status as a completely cross-platform game in which eight persons can play together seamlessly across eight different desktop computers.

As of May 2025, the current stable release of the base game, labeled “Alpha 27” because it is the 27th alpha version of an ever-in-development software project, features multiple ancient civilizations. All of those civilizations have believable architecture, attire, technologies, military techniques, and heroes –- plus, as much as possible, restored pronunciation of their original languages. The current list of playable civilizations is as follows (ordered alphabetically): Achaemenids, Athenians, Britons, Carthaginians, Gauls, Hans, Iberian Tribes, Macedonians, Mauryans, Ptolemies, Republican Romans, Seleucids, and Spartans.

A Scholarship-aware Community Endeavor

In a 2006 interview with Jason Adams of gamedev.net, the 0 A.D. project’s Paul Basar, designated in the interview notes as a member of the “History Department” of Wildfire Games, said the following about his team’s attention to historicity:

[Historical] accuracy is of the highest priority, with all weapons, helmets, armor, and shields to be of historical provenance. Literally dozens if not hundreds of historically accurate armor and weapon props have been modeled and textured, with more to come. Buildings are designed according to the style and appearance of their historical counterparts. Even the sound effects of construction have been made unique for each civilization to show the varied materials used by each people. Unit types are given in their original language, as close as can be determined … Each soldier, woman, priest, and trader is given an original personal name from his or her culture. Naval warfare has also been rigorously researched and planned by Ken Wood, our chief designer, promising one of the best historical naval combat experiences yet seen in an RTS. This is only a small sampling of the effort going into historical accuracy in 0 AD.

As the Wikipedia article about 0 A.D. says, “the historical accuracy of the game elements has been the highest development priority.” The name “0 A.D.,” however, seems to serve as a reminder that, while the game has many true-to-life elements, it is still a game. The Han Dynasty and the Spartan Empire, for example, never were at war with each other, nor did their two civilizations overlap temporally. Yet, the point with 0 A.D. is not historicity in terms of the gameplay of specific civilizations being pitted against each other but, rather, historicity about each civilization itself. The Spartans have been designed as a playable civilization with many militaristic, economic, domestic, cultural, and religious trappings from their peak as the Spartan Empire, and the Hans have been recreated in the same way. The game might be understood best as an imagined clashing of multiple real civilizations that were of prominence between circa 500 BCE and 500 CE. “0 A.D.” is the year that never was, a historically fictional nexus between civilizations and events that really were.

An example of the game’s balance between authentic historicity and engaging mechanics is the interoperation of the three main classes of human units: female citizens, citizen soldiers, and champions. As explained in the Game Manual, female citizens are the “driving force of your economy.” They specialize in gathering resources, especially food, and they are effective builders. They can attack invading units, but they are quickly outmatched in combat even by the weakest citizen soldiers. Citizen soldiers may gather resources, build, and/or fight. They have bonuses for collecting wood, metal, and stone. They are stronger than female citizens in combat, and they are able to lay the foundations for some military structures that female citizens cannot, but they also require more available resources to train (create). Furthermore, they are outmatched in combat by the third class of units, that is, champions. Champions are professional soldiers. They are the most expensive units to train, and they are incapable of gathering resources or building. Deploying them requires a deeply established economy, normally operated by a balanced mixture of female citizens and citizen soldiers. Obviously, there never has been a time in human history in which roles have been so clear cut. Yet, the facts that different sets of people play different roles inside a civilization and that the units themselves are designed with attention to history leave real fodder for class instruction.

Linguistic Practice and Contribution

If you are teaching an ancient or modern language, arguably the most effective means by which you and your students may aid the 0 A.D. project is by working to improve the game’s languages, whether by serving as editors for a language that is already present or by adding a new one.

Not all of 0 A.D.’s civilizations have yet had persons volunteer to make audio recordings of their units speaking restored versions of their respective ancient languages. The Audio Voice List in the Wildfire Games Wiki is the correct place to learn about what new translations for in-game units are needed, as well as to find up-to-date directions on how to submit them. As of May 2025, the three ancient languages that are already implemented as intended are Late Egyptian, Ancient Greek (both Attic and Koine), and (Classical) Latin. Meanwhile, there are open calls for Sanskrit and Old Persian, and the project’s leaders have place holders for (Old) Welsh and/or Anglo-Saxon, (Classical) Hebrew, and Basque.

Wayfire Games also relies entirely on community translators for the ancient and modern languages of its user interface (UI). In the official Transifex page for 0 A.D., there are (as of May 2025) over 48,000 word strings in the default (American) English language, and the project managers have a list of 122 languages (and counting, since proposals for new languages are normally accepted) at every stage of translation, from fully finished (100%) to not yet started (0%). Any university-level language class could have as a project working to contribute to any language, ancient or modern, for the UI.

Playing the game with the UI set to the language that the class is learning and/or with civilizations who are entirely crafted in that language probably would be the most enjoyable way to do linguistic practice together as a class.

Combining translation work with gameplay could make a compelling learning scenario. For example, students learning Latin might work toward bringing the half-finished Latin translation of the UI to completion for one portion of a class period, and then play as the Romans (who have finished in-game Latin) for another. Thus, they would be engaging Latin by writing it (tactilely), reading it (visually), and hearing it (aurally), as well as (presumably) by speaking it aloud (orally) with each other and the instructor.⁴

Customizing 0 A.D. for Educational Use

One aspect of 0 A.D. that makes it compelling for educational use is that the game itself is fully customizable. Here, I introduce you to three of the main ways to transform the game into a customized tool for your own didactic purposes, from simplest to most challenging: finding and installing community gameplay modifications; importing real-world geographic data to create a realistic historical scenario using Atlas, the game’s built-in terrain and scenario editor; and building a modification from scratch.

Automatically Installing Community Gameplay Modifications

The easiest way to customize 0 A.D. for your class is to make use of prepackaged community gameplay modifications (mods). At any point in time, you may find dozens to hundreds of mods hosted at various places on the Web that are compatible with the most recent game release. Since 0 A.D. was founded by game modifiers (modders), the game has been built from scratch in such a way that installing and using those mods is straightforward.

In fact, 0 A.D. comes with a built-in mod installer with click-to-install community mods that the game’s makers have verified for safety and uploaded to mod.io’s 0 A.D. set.

After launching the game, from the main menu, click “Settings,” then “Mod Selection.”

Next, click “Download Mods” (on the bottom task bar). and then click “Accept” (for mod.io’s Terms of Service) to be greeted with the full list.

Then, click on a mod, and click “Download.”

To enable the mod(s) that you desire to use, click on each one in the top menu of available mods, and then click “Enable” on the bottom task bar.

Finally, click “Save and Restart” to relaunch the game with the mod(s) of your choosing ready for use.

Two Recommended Mods

Two regularly updated, featureful mods that are available in the game’s built-in mod.io menu and that might be of particular interest to you as a reader of the Programming Historian are Community Maps 2 and Delenda Est.

Community Maps 2 adds a large, curated set of high quality gameplay terrains that their various makers have shared publicly. It is my opinion that every 0 A.D. installation should have Community Maps 2, since it adds diversity to the base game without changing its mechanics.

Delenda Est brings major additions to the civilizations and gameplay of the base game, all oriented toward historical realism and depth of strategizing. Among many other new features, Delenda Est includes a novel fourth phase called the “Empire Phase,” multiple new civilizations (as of the time of publication, these include Imperial Romans, Scythians, Suebian Germans, Syracusans, Thebans, Xiongnu, Yamatai Japanese, and Zapotecs), many options for a special start-of-game hero for each civilization that yield different bonuses, enslavement of foreign peoples, cultic worship, majorly reworked economics (including two new resources, Glory and Coin, to accompany the base game’s original four of Wood, Food, Metal, and Stone), and expanded technological trees for every civilization from the base game.

While I have many good things to write about Delenda Est, I only recommend that you bring it into your classroom if you are able to schedule multiple hours for learning gameplay mechanics. The base game, as a real-time strategy game, has a modest but non-negligible learning curve, and Delenda Est introduces a steeper one. Further, Delenda Est is only suited for multiplayer use, since AI (computer) players are not programmed to handle its special mechanics.

Manual Mod Installation

Installing a prepackaged mod outside 0 A.D.’s built-in mod.io menu (e.g. downloaded directly from a repository on GitHub) is trivial by design. With a mod downloaded as a .pyromod (custom Pyrogensis package) or .zip file, you may either right click the mod file and select “Open with 0 A.D.” or perform the same task at the command line with pyrogenesis [file].pyromod or pyrogenesis [file].zip. Enable the mod inside the same in-game “Mod Selection” menu that you use with mods installed via the built-in mod.io menu.

Alternatively, you could move the entire mod folder into */mods yourself, without having the game engine handle the installation, but you must make sure that the mod’s parent folder and .zip that it contains have the exact same name as what is listed in the mod’s mod.json file.

To install the mod manually, locate the correct folder for inserting mods in the game’s installation directory, specifically */mods. The Wiki currently specifies the Windows folder as C:\Users\{name_of_user}\Documents\My Games\0ad\mods\, the MacOS folder as ~/Library/Application Support/0ad/mods/, and the default Unix-like OS folder as ~/.local/share/0ad/mods/. Copy and paste the mod’s parent folder (the entire mod) into that folder. Enable the mod inside the in-game “Mod Selection” menu.

For more information, here are the 0 A.D. Wiki’s official directions for manual mod installation.

Next Steps with Community Mods

I recommend that you start by installing and enabling Community Maps 2 via the game’s built-in mod.io-linked installation menu and trying some of its lovely terrains while you become familiar with the base game. Then, move to Delenda Est or another vetted mod available via mod.io that you might like to try in your own teaching context.

Millenium A.D., for example, which is focused on the ninth and tenth centuries CE, has tens of thousands of downloads. As of May 2025, it is more of a work-in-progress than Delenda Est, but it already has playable iterations of the Anglo-Saxons, Byzantines, Carolingians, Norse, Rus, and Ummayads. There are many other mods even in the mod.io curated set that add new civilizations and/or other features that might be relevant for your classroom.

Importing Geographic Data to Create Historical Scenarios

As a teacher of history, you might wish to create fully custom historical scenarios in 0 A.D. to showcase for your classes, or you might wish to have your students make such scenarios themselves as class projects. For the most immersive experience possible, it is best to import real-world geographic data into the videogame.⁵ While you work through the steps outlined below, I recommend that you have the official Atlas Manual in the Wildfire Games Wiki open in case you should desire additional information about how to use Atlas, 0 A.D.’s built-in terrain and scenario editor.

Also, as a preparatory note, whenever you click “Save” (or “Save As”) inside Atlas, make sure that you always choose Atlas’s option for a scenario – not a skirmish (nor a tutorial).

Scenarios have predefined civilizations, teams, units, and so on while allowing full multiplayer gameplay.

1. Choose a Scenario

The ideal historical scenario for recreation in 0 A.D. would be a battle between two or more civilizations that are available either in the base game or via a mod that took place in a location with sufficient geological diversity for intriguing gameplay.

If you are a Classicist teaching a history class, then you might choose one of the critical battles from the Gallic Wars. Late Republican Romans are in the base game, and early Imperial Romans are in the Delenda Est mod. Gauls and Britons are both in the base game, too.

The definitive Battle of Bibracte took place about sixteen miles south of the actual historical Bibracte hilltop Gallic fort, which is now known as Mont Beuvray.⁶ Beuvray is in a strip of hillcountry with hundreds of meters of elevational changes, and the surrounding area contains rich forests, open fields, and both rivers and streams. Julius Caesar’s victory at Bibracte was crucial to his eventual triumph over Gaul.

In this lesson, you will learn to make a simple recreation of the Battle of Bibracte.

2. Find a Topographic Map

Although there are many databases of topographies online, topographic-map.com is well suited for your use case because it exclusively makes use of open access data, possesses detailed topographies of (nearly) everywhere around the globe, and presents topographies in a color-coded format that is easy to modify for importation into Atlas.

Visit topographic-map.com, use the master search tool to find the topography that you would like to import, and select a (roughly) square area around the region that you require – with a bit of extra space on all sides to spare – using your operating system’s screenshot or snipping tool. In order to have room for adjustments, aim for roughly 1024x1024 pixels (a more-or-less square shape between, say, 512x512 and 2048x2048).

To feature the diverse landscape of the region surrounding Mont Beuvray, and to capture that the combat in the Battle of Bibracte actually took place some 25 kilometers south of the key Gallic oppidum (fortified settlement), I purposefully take a screenshot that includes a larger area.

3. Modify the Topographic Map Image

Per the “Heightmap Import” section of the Atlas Manual in the Wildfire Games Wiki, the final image must be a grayscale .png that is a perfect square with power of 2 dimensions. The brightness of a particular part of an image determines its elevation, with relative darkness corresponding to lower elevation and relative lightness corresponding to higher elevation.

The hightmap importer in Atlas takes the image file as-is without any import time options, so it is important to modify the image to be as close to ideal for Atlas as possible prior to importing. Your objective is to minimize the amount of tuning that you will need to do after the import with Atlas’s terrain tools.

Each of the following power of 2 dimensions corresponds with an in-game terrain size that is explained in more detail (here) in the source code: 128x128 (Tiny), 192x192 (Small), 256x256 (Normal), 320x320 (Medium), 384x384 (Large), 448x448 (Very Large), and 512x512 (Giant). I view the Large (384x384) and Very Large (448x448) sizes to be ideal for full 8-player matches, which probably makes them the best for most classroom usage situations (contrary to Giant, which requires loading so many resources that it can cause game slowdowns). At the same time, smaller sized terrains require (much) less work in Atlas to make realistic.

Since I am purposefully making a recreation of a large-scale battle that had tens of thousands of warring men on a geographically diverse parcel of land, I will make my terrain inside a 512x512 pixel square, that is, the right size to be imported as a Giant terrain in Atlas.

The final version of the terrain in-game will be a perfect circle from inside your square with a diameter the same as the length of one of the square’s sides (e.g. 512 pixels), and some space just inside the perimeter of that circle will not be usable in-game.

There are many workflows by which you could specify the image size and convert the image to grayscale. In GIMP, I recommend this simple one that is likely to remain viable through future software updates:⁷

• From the menu (top bar), click “File” -> “New,” and type the square value of your choosing (e.g. Width = 512 px and Height = 512 px), then click “OK.”
• Click “File” -> “Open as Layer,” and select your unedited topographic map image.
• Click “Layer” -> “Scale,” and, leaving the proportions locked (the chain icon connected), type the desired width or height value (e.g. my width is 911 px and height is 814 px, so I type “512” next to Height, which makes the Width value 573 automatically) and click “Scale.”
• With the Toolbox open (click “Windows” -> “Toolbox”), click the four-way icon (or tap “M” on your keyboard) to select the “Move” tool, and move the layer so that the relevant geographic details are where you would like them to be in the final circular in-game terrain. Then, click “Layer” -> “Layer to Image Size” to remove everything outside the correct image dimensions from the layer.
• Click “Select” -> “None.”
• Click “Image” -> “Mode” -> “Grayscale.”
• Click “File” -> “Save a copy” to save a version of the image file upon which you can fallback at any time.

At this point, you have a correctly sized image that you theoretically could export as a grayscale .png file for import into Atlas, but it is most probable that it has harsh edges and stark contrasts that would yield a terrain with unplayably (and unrealistically) sharp rises and falls of elevation. Plus, if you selected topographic data in which areas with higher elevation appear darker rather than lighter when converted to grayscale (as is what happens with images from topographic-map.com), then many areas will be imported with elevational changes that are the opposite of what they should be.

First, regardless of your specific terrain choice, you will need to smooth the image’s internal rough edges by introducing blur. In GIMP, do the following: Click “Filters” -> “Blur” -> “Gaussian Blur.” Set the Size X and Size Y values to between 2.00 and 6.00, probably about 3.50 to start. The image should be distorted enough that it lacks any rigid edges but not so distorted that its features are unrecognizable. Favor distortion over clarity.

Second, if you have a topographic map image in which areas of elevated terrain appear as darker rather than lighter, then you should rectify the issue by inverting the colors of those specific regions. Here is one way to achieve this in GIMP:

• Click “Select” -> “By Color,” and click on the relevant color to invert. You might need to click multiple times; GIMP compounds the selection automatically. (GIMP also allows undoing individual steps within compounded selections with CTRL+Z or “Edit” -> “Undo.”)
• Click “Colors” -> “Brightness-Contrast,” and increase both values until the terrain that should be lighter (elevated) is in fact lighter.
• For my specific image, the edges of the mountainous terrain have steep dark spots after this. I blur their edges manually with the “Smudge” tool (after clicking the pointing finger in the Toolbox or tapping “S” on my keyboard). I also add just a few drops of white paint (using the “Paint” tool, which is available by clicking the paintbrush icon in the Toolbox or tapping “P” on my keyboard) to the area in the north with especially higher peaks, including Mont Beuvray itself.

Here is the final version of my image inside GIMP after doing all of these steps. I click “File” -> “Export,” and I type “beauvray.png” as the name before unselecting all .png filetype export options (to make a simple file), choosing “16bpc GRAYA” for 16-bit grayscale with alpha, and turning off compression (setting the value to 0) in order to have the highest quality export possible.

After clicking “Export,” we are ready to advance to the next step, that is, actually importing the heightmap into Atlas.

4. Import the Topographic Map Image into Atlas

Now that you have chosen a historical scenario to recreate, found a topographic map to import, and edited the topographic map image, importing your topography into Atlas will be easy:

First, Open 0 A.D.

From the main menu, click “Scenario Editor” to launch Atlas. When asked “Would you like to quit 0 A.D. and open the Scenario Editor?”, click “Yes.”

• Inside Atlas, click “File” -> “Open Heightmap,” and select the topographic map image that you have edited.

Here is how mine looks:

The source image could have used a bit more blurring to reduce the harshness (the flat areas ought to be flatter, and the mountains ought to have less steep cliffs), as well as more contrast so that the mountains are actually at a noticeably higher altitude than the surrounding flatlands. After quickly reopening my saved backup in GIMP and making both of those changes (per step 3), this is the result:

5. Add, Adjust, and Smoothen the Terrain’s Features

Before doing anything else to your terrain in Atlas, you ought to add water to it, perform a general landscape smoothing, and adjust its other core (elevational) features. These three tasks lay the foundation for everything else that you will place in your gameplay scenario.

Here is how you add water to the terrain. From the main menu, click the sun-shaped icon for “Environment” settings. Then, drag the “Water height” slider until there is about the right amount of water in the terrain’s points of low elevation (where there ought to be water).

To smooth the terrain, click the plain green icon for “Terrain” settings. Then, click “Smooth,” and adjust the size of the tool to about 20 (leaving the strength at about 10), and work around the map as needed (left clicking on the areas for correction and dragging the cursor over them).

Here is how my terrain looks after adding water and performing an initial smoothing:

The other adjustments that you will need to perform at this stage will depend upon your terrain. Experiment with the different terrain tools, keeping sizes of the modifiers small (and backup copies of the terrain saved) until you reach your desired result.

For my sample, I have used the “Flatten,” “Modify,” and “Smooth” terrain adjustment tools only for a few minutes. Also, I have added a few rocky biomes to the northern mountains. Biomes are found on the bottom task bar in Atlas.

This is my result:

6. Add Flora and Fauna to the Terrain

Now that you have your terrain’s core features in place, it is time for you to add flora and fauna. Your objective should not be to effect a pebble-for-pebble and bird-for-bird depiction of the real-world equivalent but, rather, to capture its overall character and, more importantly, special features that matter for the historical scenario.

In Atlas, you will place all flora and fauna with the the “Object” tool, which has a person-shaped icon. Flora and fauna are categorized as units belonging to Gaia (Mother Earth). For a full list, then, filter by “gaia” (lowercase) in the top search bar.

Mont Beuvray has a blend of deciduous and coniferous vegitation. Although the surrounding flatlands are all open fields today, they probably were forested in antiquity. Accordingly, I start adding decidious and coniferous trees throughout the terrain.

I do the same with deer and other wildlife native to the woodlands of central France.

Make sure to add all four of the game’s resources – wood, stone, metal, and food – to your terrain, whether or not the real-world equivalent actually possesses all four of those resources. Without them, the scenario will not be playable. Wood may be found in gaia/tree/, stone in gaia/rock/, and metal in gaia/ore/. For food, you may add any huntable animal, berry bushes, or fruit trees; browse through Gaia’s flora and fauna for food options that make sense for your terrain.

7. Add Scenario-specific Features

Next, you need to add scenario-specific features to your terrain, that is, the units, structures, and everything else that will make the historical scenario actually playable.

Most importantly, each civilization ought to start either with a civic center (which defines the civilization’s starting territory while allowing the creation of female citizens and basic citizen soldiers) or sufficient resources to build a civic center (typically, as of Alpha 27, 500 Wood, 500 Stone, and 500 Metal – but it is important to check the requirements for each specific civilization inside a specific game version), as well as at least 1 unit capable of resource gathering and building.

Customarily, in addition to a civic center (sorted by “[civilization]/civil” in the Object tool), each civilization starts with two or three female citizens for gathering resources and building; two or three citizen soldiers for gathering resources, building, and (if needed) doing early game military defense; and a cavalryman who may serve as a scout to explore the terrain. Remember that each in-game unit can represent tens, hundreds, or even thousands of real-world counterparts.

For the Battle of Bibracte, I need to setup two civilizations: the Romans and the Gauls. For simplicity’s sake, I have one player assigned per civilization (two total). I place the Gallic fortress on Mont Beuvray itself and a smaller Roman encampment in a field by the main river to the south, but I give considerably more starting resources to the Romans than to the Gauls.

Everything that I need to setup a game for two players with the correct civilizations and resources is located in the “Player” tab, whose icon looks like a small human face. First, I click that tab. Then, I set the number of players to 2. Finally, I set Player 1 on Team 1 as the Gauls with the name “Helvetii” and relatively low starting resources and Player 2 on Team 2 as the Romans with the name “Caesar’s Legions” and relatively high starting resources:

Next, I switch to the “Object” tab, and on the bottom of the screen, I click “Player 2” to make Player 2, the Roman civilization’s manager, the owner of the units. I add a Roman Castra (Army Camp, a specialty structure) in the south, which is less advanced than a civic center but allows the creation of citizen soldiers and some siege weapons. I also place a proper civic center, mainly so that the Romans actually control their own starting territory. I set a few citizen soldiers and a cavalryman, all filtered by “rome” in the “Object” tab’s search bar:

After switching the Player to Player 1 on the bottom of the screen (inside the “Object” tab), I create a Gallic Fortress atop Mont Beuvray, and I place some Gallic infantry javelineers (citizen soldiers) and female citizens.

To rotate units while placing them, keep the left mouse button pressed and move it up or down. You also may adjust the rotation and/or location of any placed unit by clicking the four-way directional icon in Atlas and then clicking on the unit whose rotation and/or location you wish to change.

What you might do with these tools will depend on your specific scenario, but the basic steps will be the same

8. Save the scenario, and distribute it.

Having finished crafting the historical scenario, it is time to save it for distribution. First, click the gear-shaped icon to switch to the “Map” tab. Next, enter a name for the scenario, as well as a short (1-2 sentence) description.

Finally, click “File” -> “Save,” and type an easy-to-remember file name. Do not change any information under the “Random Map” area, since you are not making a Random Map. Custom scenarios are automatically saved in the game’s default “mod” folder (see above), specifically /0ad/mods/user/maps/scenarios/.

To distribute the scenario, share the scenario’s .xml and .pmp files (two files) from that location with each person whom you would like to play with you, instructing each person to place those two files in her/his /0ad/mods/user/maps/scenarios/ folder. (If the folder “maps” and sub-folder “scenarios” do not exist, create them before pasting the files.)

9. Play the scenario.

You may now play your custom historical scenario as either a singleplayer or multiplayer game. If this is the first time that you have setup a game in 0 A.D., I recommend that you read the “Setting up a game” article in the Wildfire Games Wiki. For classroom usage, the “Hosting / Joining a Multiplayer game” sub-section will be most important.

For my example, I will host a multiplayer game from a computer running FreeBSD and join it from a computer running OpenBSD. (The steps will be the same for you regardless of what desktop operating systems you are using.) After copying the scenario’s two files into the correct directory on the second machine, I return to the hosting machine. Then, I open 0 A.D. and click “Multiplayer” -> “Host Game.” I choose “Map Type” as “Scenario” and click the filter “All Maps” before selecting “Bibracte.” I join from the second machine by typing the host machine’s local IP address, and this is the result:

After “Roman Ruffian” (Player 2) clicks “I’m ready,” “Gallic Guy” (Player 1, the host) clicks “Start Game,” and the match begins:

Enjoy playful creativity in the classroom with a free and open source computer game.

Beyond? Join the Community, Build a Modification from Scratch, and More

The most advanced way to incorporate 0 A.D. into the classroom is to build a gameplay modification (mod) from scratch. You, the instructor, might wish to bring a wholly new civilization into the game. You might like to make a custom hero for one of the base game’s civilizations. You might assign mod making as a class project. Regardless of what you should decide to do, at the level of building a new mod for a game that is designed to be modifiable, your possibilities are only limited by the the Pyrogenesis game engine’s own limits. The Modding Guide states:

0 A.D. has been designed from the beginning for ease of modding. Not just art and sound, but also the code which makes the game come to life. All the textures, 3D models, animations, sounds, fonts, and scenarios found in the game are packaged into “mods” (modifications). Additionally, a large amount of the game’s logic (written in JavaScript) is packaged in mods.

I already have written about the two best sources of documentation for building a 0 A.D. mod from scratch: the official Wildfire Games Wiki and the Wildfire Games Forums. You should begin by reading the “0 A.D. Modding Guide” and “0 A.D. Mod Layout” entries in the Wiki, which themselves are cross-linked with information about what belongs where, which values change what settings, what sorts of 3D objects may be imported into the game, and more. The Game Modification Forum has many active members who are eager to assist each other. As long as you have attempted to find an answer to your question or solution to your problem yourself, and you have documented the steps that you have taken toward that end, you are likely to receive a helpful answer there.

The Portuguese language (Brazilian) Youtube channel “Ágora 0AD” also has a superb “How to Mod” series, and you may find other information scattered throughout the Web. Yet, since the 0 A.D. project only progresses by end-user upstreaming, I recommend that you use and contribute back to the Wiki and the Forums, thinking of them as both the ultimate sources of truth for 0 A.D. modding and the final destinations for what you might uncover through your work on your modding activities.

If you should have an idea for a new gameplay modification, read the Modding Guide and Mod Layout pages in the Wiki. Then, outline a plan for the mod before starting to work on it.

The 0 A.D. project points to the superiority of free and open source software over proprietary software for education. With a large playerbase whose members are devoted to realism, realism is more likely to be actualized than in, say, a traditionally corporate-backed game project. Further, 0 A.D.: Empires Ascendant is fully customizable – even able to be overhauled – for educational use. Limitless learning is better than limited learning.

Endnotes