NPCs, Items, Enemies, Quest Debugger

I’ve been hard at work the last couple of weeks, finally making serious inroads into the real meat of the quest system. Here’s a quick diary of my progress since last post. If you follow me on Twitter, you’ve already seen most of this, although there’s a new video at the end you might enjoy.

In the last post, I talked about using buildings as quest sites. This has allowed me to start work on placing NPCs, items, and enemies as part of quests, and to support branching quest execution based on where player is in world.

When a named NPC is reserved by quest system, Daggerfall Unity handles all the book-keeping to move that NPC to the quest site. I tested this out using King Gothryd at first. Once the new quest site is determined and Gothryd is reserved, scene builders will no longer deploy him at the usual home location – unless the quest specifies the atHome flag at time of NPC reservation. In screenshot below, Gothryd has already left for the quest site.

 

The quest system then generates a SiteLink between target Place and Person resources. When the player visits the target location, scene builders need to place Gothryd at that location. Here’s Gothryd at the end of his journey.

 

I wanted to take a short break from NPCs and moved onto items briefly. There’s a few different ways Daggerfall uses Item resources in quests. They might added directly to your inventory, placed in a dungeon, or used as a permanent reward. Different quest conditions will also trigger based on whether player is carrying a certain item or not. I still have a lot to do here, but have made a start on the first case – adding an item directly to player inventory. The parchment with a green background below is the first real quest item in Daggerfall Unity. Specifically, it’s the letter from Brisienna.

 

At this point the quest engine is getting advanced enough that I need more detail on what’s happening under the hood at any time. I put together a quest debugger that shows the various Task and Timer states for a running quest. I plan to make this capable of step-through execution in the short term. The debugger shows which tasks are active/inactive and which timers are pending/running/complete. After setting this up, I could finally resolve many bugs in execution flow. I also added proper support for persist-until tasks, global variable links, and rearming tasks designed to switch on and off.

 

I’m pleased to say the quest system is all coming together rather quickly now. There’s still a huge amount of work to do, but most of the hard problems have been solved now and I’m just building out action support and fixing bugs. Here’s a little video of the current state of the quest system. Some of the early quests are working nicely now.

As a bonus, this video also shows the new skill tracking and player levelling by Allofich. Yep, it’s possible to level-up in Daggerfall Unity now thanks to his efforts. Great work Allofich!

Quest Buildings And PcAt Condition

Now that buildings and NPCs can be identified in the game world, I can finally start linking together parts of quest system to world. The clearest starting point is quest buildings, as a majority of quests in Daggerfall will send player to a building somewhere in the world.

If you’ve been following my progress on quest system for a while, you already know a lot of technical progress has been made on the back-end. Without forcing you to recap on past articles, here’s a brief summary of quest system in its current state:

  • Quest scripts are generated by Template v1.11 by Donald Tipton. This has long been the go-to solution for adding new quests to classic Daggerfall. By adopting this scripting format, it becomes possible to compile scripts between both Daggerfall and Daggerfall Unity for testing. And it means anyone with experience writing quests for Daggerfall can already write quests for Daggerfall Unity.
  • Daggerfall Unity has a JIT quest compiler which builds quest scripts at runtime. This means you can edit, start, and stop quests without once closing the game. This will be even more useful once the Quest Inspector UI is ready.
  • The QuestMachine execution environment runs compiled quests like small virtual machines inside your game session. It interfaces with the world and does all the necessary housekeeping for running quests.
  • Quests are made up of resources (Place, Person, Item, etc.) and Actions (perform some task). Some actions are also conditional (do task when condition is true). Almost all of Daggerfall’s high-level gameplay is driven by the quest system. Even some things you might not expect (such as Lysandus screaming VENGEANCE! at night) are accomplished by quests.

 

When adding building selection to game, one of my first problems was how do I locate the building in whatever town player is in. Daggerfall Unity doesn’t have wandering NPCs to mark buildings on your map quite yet. Not a problem for named buildings like taverns and shops because these are visible on the automap, but what about some random residence in town? How do I get the player there for testing?

The solution I landed on was to add a simple quest compass on the HUD. This will show the direction, name, and distance to target door. Fortunately, I already track building entrances in the world. What’s needed is to build a set of marker positions based on active quests. I start by just adding a test sphere on quest target doors.

 

That blob above sits perfectly on the door to my quest building. Now I need to show that as text and distance. The HUD text overlay below align with doors in camera space and show distance to multiple targets.

 

And finally the building name. This marker can direct quest developers straight to all active quest sites in their current location. Of course, anyone will be able to turn this on from the quest inspector UI if they would like a quest compass. I’m almost certainly going to expand this system out for quest items in dungeons and other targets in the future.

 

I can now enable the quest journal, something Lypyl implemented perfectly some time back. I wire up the keybinds and UI to allow player to open quest journal, and find logged quest information sitting there as expected.

 

What you can’t easily see above is that some text macro support has been added as well. For example, %pcn resolves to player’s full character name, _buildingSymbol_ expands to building name, __buildingSymbol_ expands to location name, and ____buildingSymbol_ expands to region name. This is all part of the text engine inside Daggerfall I’ve had to reimplement in Daggerfall Unity.

With local building support out of the way, the next step is remote buildings elsewhere in the same region. This involves a bit more work, but in a few hours it’s possible to send player anywhere in the game world.

 

The final piece is to implement PcAt conditional action, which detects when player has entered target building and does something. In this test quest, I just display a popup and end the quest.

 

This is an important milestone for questing in Daggerfall Unity. It means a lot of the hard groundwork has been completed and the real work, the stuff visible to the player, can commence. This is a huge relief for me because I can finally show off my progress in a meaningful way with screenshots and videos. As important as all the code back-end is to outcome, its been very difficult to show progress which sometimes makes it feel like nothing is happening.

To celebrate visible progress, here’s the first video of Daggerfall Unity’s fledgling quest system in action.

 

For more frequent updates on Daggerfall Unity, follow me on Twitter @gav_clayton.

Identifying Buildings And NPCs

In my last post, I talked about the “Place” quest resource and merging map-level data down to block-level. The next step from here is to propagate this information to scene-level where the player ultimately lives. I decided to tackle this along with a start on Daggerfall’s interaction modes, i.e. Steal, Grab, Info, Talk which are by default bound to keys F1-F4. What I’m most interested in here is the ability to perform an info click directly on a building to discover its name.

First step was to quickly implement the mode switch itself. Key-kinds were already in place inside the InputManager class, all I needed were a few more lines of code to track which mode player was in and a new HUD label to present switch to user. After several minutes it was possible to flip between the 4 interaction modes.

 

Next, I needed a way of detecting when player clicks on a building. I already track player clicks in PlayerActivate class, and can detect clicks on static scenery and doors, but not on the building model itself. I go to work looking for an efficient way to manage this. Each Daggerfall model contains a radius value stating the overall size from its centre point. This seemed like a good place to start, so I overlay the radius as a sphere collider on test buildings.

 

Keep in mind that I’m not storing individual building models at scene level, the entire block of buildings above is combined into one large model. This is more efficient for rendering and results in fewer draw calls to the graphics card. So I don’t know which building player has clicked on – I just know they’ve clicked a combined block model and I need to resolve that back to a specific building. The sphere colliders would do the job, but they unfortunately suffer from a lot of overlap. Depending on where player is standing and where they clicked on the building, it’s possible for that target point to be inside two or three different building spheres. There are ways of handling this of course, but I decided to go with box colliders instead that will tightly wrap Daggerfall’s little box houses.

Before I can implement boxes, I had to go right back to the procedural mesh builders that extract data from ARCH3D.BSA (Daggerfall’s 3D model archive). During the vertex conversion process, I added some tracking for minimum and maximum vertex positions from origin to get the overall size of models in X, Y, Z space. Because the models are being constructed procedurally, and I have to process that information anyway, this step adds almost no overhead to the job of loading models at runtime. I now have what I need to construct a tight bounding box around any model effectively for free.

Then I just had to pass that information to scene builders. The end result looks like this.

 

Every building now has a nice crisp bounding box trigger collider. While this is great to visualise the bounds, I’m not happy with adding so many GameObjects to scene. A large city like Daggerfall will add around 800+ new collider GameObjects. If a few large cities are in the world at once, then it’s very possible that 2000-3000 colliders would be added to scene, the majority of which will never be used. Not ideal from an optimisation point of view.

To work around this, I used the same solution I came up with for doors. I store the box information for every building on the block GameObject itself using component DaggerfallStaticBuildings. This is just a small amount of raw data stored on each block. When the player clicks on a block in scene level, a single box trigger is instantiated and tested for each of the buildings in that block, usually no more than 5-14 buildings. The world-space point of impact for hit ray is tested against known buildings in that block (and only those buildings). If a hit point intersects with a known building trigger in world space, then everything we need to know about that building from scene layout time is returned to PlayerActivate.

The end result is zero new collider objects in the scene and only a small amount of overhead for storing building data and testing hits, which happens only when the player clicks on a city block. The net result has practically no performance impact and still fits nicely hand in glove with Unity’s physics setup. With all of that in place, player can finally make info clicks on buildings in scene.

While I was working on this, I decided to add shop quality text. When the player enters a shop in Daggerfall, the overall quality level is presented to player as a popup. Each shop has a quality value between 1 and 20 with a total of 5 different quality popups. I’ve long assumed it was just qualityValue/4 to get the popup, but testing proved otherwise. Daggerfall weights the quality text a bit more in the mid-range that the extreme low or high ends. After checking shops in Daggerfall city and Gothway Garden, I think I have the weightings worked out. Anyway, It’s something that can be easily tweaked later if needed. Now when player enters a shop, the quality text will popup like in classic.

 

Because the popup actually prevents player from entering building until they click a second time, I added a quick INI option to present quality text to HUD instead, with a configurable delay. With this option configured in INI (ShopQualityPresentation=1), you can enter every building with a single click and watch the quality text scroll off HUD. You can also set ShopQualityPresentation=2 just to turn off quality text completely.

 

While I was on a roll with the whole info setup, I made a start on identifying static NPCs. These are the flat people standing around inside buildings and interior environments like Daggerfall Castle. This will be critical to dialogue as part of questing system eventually, so might as well break some ground for later. The first part of this was simple, just detecting when player clicks on an NPC.

 

Yep, that’s an NPC alright. Exactly how an NPC is detected had to evolve a little over the process of getting this initial text in place. I previously did this by detecting if the billboard had a faction and a gender – something I assumed only NPC billboards would have. This turned out not to be the case and there are plenty of factionless NPCs standing around. Also, the NPCs in building interiors had a different metadata setup to NPCs in dungeons. Just like Daggerfall to use two different data structures for effectively similar things. I ultimately determined NPC status by the texture archive flat belonged to. There are a small range of NPC-specific texture archives and this served better than faction to determine if player has clicked an NPC or not. In the process of doing all this, I actually gained some better understanding of a particular bitfield and found a new gender bit assigned to NPC records.

Before I can identify an NPC properly, I need to use their faction information. An NPC with faction type=4 is an individual NPC which means their name comes directly from faction data. Other NPCs just get a random name generated based on their gender. So before diving any farther down this rabbit hole, I have to implement factions for the player.

I had written faction file reader around a year ago, but this just reads the initial database from FACTION.TXT in game data. In Daggerfall, this initial faction data is assigned to player character at time of creation and persists with player all through their adventuring career. Every interaction can raise or lower their standing with a particular group. To start tracking faction data properly, and to make this information available to NPC info clicks, I added the PersistentFactionData class to player entity. This class represents the player’s current standing with all factions and provides basic lookup functionality. This has already been wired up to save/load system, so when you save a game in future builds, your faction data will be saved as well. This is also an important milestone for the questing system.

With faction data on the player, we can identify individual NPCs like King Gothryd and Queen Aubk-i.

 

But it means that group-based NPCs don’t resolve properly by faction alone.

 

These NPCs need to have a random name based on gender. Thankfully I’ve already written the random name generators, as these were required for building names and elsewhere. The only thing I’m missing is the correct seed value to generate the exact NPC name that Daggerfall uses. For anyone unfamiliar with random generators, the same seed value will always output the same result. Unfortunately, I wasn’t able to find the seed value Daggerfall was using to name NPCs. You’d think this would be obvious like it was for buildings, but sadly not. I decided that one random name is probably as good as any other for these non-essential NPCs and just used their record offset as a seed value. This means they will always have the same persistent name generated each time, it just won’t be the same name as in classic. If the correct seed value is ever located, I can just feed this into the generator instead and the correct name will pop out. Until then, it probably doesn’t really matter. Say hello to random NPC Alabyval Coppersmith.

 

At the end of this little coding adventure, all of the following has fallen into place:

  • Change activation mode between Steal, Grab, Info, Talk.
  • Identify buildings and static NPCs.
  • Shop quality text is now displayed when entering a shop.
  • Faction data now exists on player entity and persists with your save games.
  • The foundation for checking NPCs in scene are ready for “Person” quest resource.
  • The raw data needed for “Place” quest resource now in scene.

With all that done, I can go back to working on “Place” resource and “pc at” condition for quest system. You can see what a rabbit-hole this whole quest setup is. It touches on so many different parts of gameplay that sometimes I need to go in a different direction for a while before I can loop back and progress on what I’m trying to build. But it all adds up, and every tiny step brings us closer to real gameplay.

For more frequent updates on Daggerfall Unity, follow me on Twitter @gav_clayton.

Questing: Place Resource

I’ve decided to go in a slightly different direction regarding dev articles about quest system from now on. Instead of the traditional numbered sequence split into a few parts, I will post more about what I’m working on in the moment. There are two reasons for this. First, questing is a huge subject that resists being neatly split into a progressive narrative like items or streaming terrain. I often have to cross back and forth between related systems. Second, it gets a bit daunting trying to construct that narrative from such fragmented work. The end result is that I’m posting less and feeling more weight on my shoulders every time I try to construct a post. Just how do I describe to everyone I spent weeks working on research without a satisfying answer to a particular problem?

My solution is to tear the band-aid off and just post something. I’m slowly learning that many people enjoy the development process itself, including the potential for frustration and dead ends. Those outcomes aren’t particularly enjoyable for me when they happen, but maybe I can turn them into something positive and entertain my readers. This should result in more posts but they will often be shorter (which in itself might be a good thing). This post probably won’t be shorter, but it is my first in a while. 🙂

So here’s what I’ve been working through lately…

In a QBN section, Daggerfall quests defines resources that kind of glue the whole shebang together. They define places in the world, people to visit, timers, items, and enemies. Basically all the world-stuff player will contact to unroll that quest’s execution. A high-priority resource is Place, which defines locations the player must use in the quest, like a dungeon, shop, or residence. Here are some examples.

Place _mondung_ remote dungeon9
Place _house_ local house2
Place _inn_ local tavern
Place _palace_ remote palace
Place PiratesHold permanent PirateerHold1

To deconstruct the above: Place tells the compiler this is a place resource; _symbol_ is the name of that place for the compiler to reference; remote/local/permanent is where to select that place from; and the final bit is site which tells quest engine what type of place to select. The site code is actually a reference to a places data table which defines the parameters for these site types. I won’t go into these in much detail, just keep in mind they define what kind of building or dungeon to select.

Let’s use “local tavern” for now. This means find a random tavern within the same town as where player received quest. If this was “remote tavern”, we’d select a random tavern from another town in the same region. The site code “tavern” is then looked up in the places data table and the parameters tell us this is building type 15 (0x0F).

Now the quest engine knows it needs a tavern (building type 15) and it should select from the map player is currently in. Fortunately, Daggerfall keeps a handy list of buildings for every map definition in MAPS.BSA. This gives us information like the building name seed, faction, quality (“rusty relics” through “incense burning”), and best of all building type. Great! We already know we need a tavern, and it’s trivial to select taverns from this list of buildings and grab one at random. Now we have our quest location… well, almost.

A Daggerfall city is made up of geomorph-like blocks – up to 8×8 blocks for really big cities. They are like puzzle pieces laid out on a grid. Here’s the block layout for the City of Daggerfall, you might recognise this from Daggerfall Modelling.

 

Every block also carries a list of buildings it contains, sharing the same data structure as MAPS.BSA – with a few differences. One key difference is that a few of the values present at map level (e.g. name seed) are not present at block level. The reason for this is obvious when you consider how often blocks are reused across locations. If the name seed was stored in block data, our tavern would have the same name in every location that block is used. Thus the name seed is carried at map level and merged down to block level as needed. Same goes for the block texturing, which changes based on climate. Put together, this all makes blocks somewhat polymorphic in that they can take different forms depending on the location they belong to.

Back to our tavern which we found in building list at map level, how then do we map this to the actual physical building at block level? Besides other jobs like setting the correct names on automap, this is needed to determine correct physical location of quest buildings in the world. This is where some of my troubles started.

At time of writing, it is unknown exactly how Daggerfall links building data at map level down to building data at block level. To compound my problems, only a subset of buildings are represented at map level. A large city like Daggerfall will have many more physical buildings than listed for that location in MAPS.BSA. Even in small locations where the totals match, the individual building type counts don’t always match. For example, map data might define 6x House1 and 4x House2, while block data will contain 5x House1 and 5x House2. There doesn’t seem to be any consistent way to link these two sets of data together. If this were a relational database, I would expect a stable primary and foreign key matching on both sides. But not only does a key not seem to exist between them, the totals cannot be trusted to line up between map and block buildings.

Despite this, I have been able to make some good progress. I discovered that named buildings (taverns, stores, guilds, etc.) are always in the same order in the map building data as the block layout data. Couple this with the building name seed discussed a while back, it’s possible to merge down named buildings without much trouble. This is also needed for the automap like below. Credit goes to Nystul for the excellent automap implementation.

 

When it comes to generic premises like House1/House2, things become more difficult. I can’t depend on an exact match between building type distribution, and can’t find a way these could possibly be linked in a stable manner. Both Lypyl and myself have been through the binary data in great detail. Despite finding a few other interesting leads, we have not found a satisfying answer to the question of mapping non-named buildings from map level to block level.

After many frustrating weeks of searching, I’ve more or less come to the conclusion that it really doesn’t matter. The only buildings that need to be mapped 1:1 are named buildings, and I already have a working solution for this. When it comes to generic premises (which are selected randomly anyway) it should not matter which House1 or House2, etc. Daggerfall Unity selects for a quest. As long as the end behaviour closely matches that of Daggerfall by selecting a building of the correct type, I’m basically free to implement this in a manner suitable for Daggerfall Unity.

In hindsight, the apparent lack of stable linking between map and block data could account for some quirks in Daggerfall itself. For example, it’s not uncommon to find a tavern which Daggerfall thinks is a residence. And only about half the buildings in most towns can be entered anyway (“this house has nothing of value”). My feeling now is that when a location is loaded, Daggerfall simply distributes map building data amongst block buildings using some kind of algorithm where named buildings are populated first and generic buildings are distributed to best effort. As long as named buildings are handled (they are), and other buildings are selected randomly (they seem to be), then I can at least reproduce this behaviour in a way that feels exactly the same to the player. My solution might not be exactly what Daggerfall is doing, but it’s likely very close.

So that’s where I’m at right now – working through implementation of Place resource, selecting locations in the world, and ensuring this maps to physical environment correctly. During this process, I’ve added some fun bits along the way such as the flavour text when entering a dungeon area outdoors. This text is based on dungeon type and reads from strings in Daggerfall’s text database using the same variations.

The other side of a Place resource is the “pc at” condition which tests if player is at a Place or not. This is highly intertwined with Place resource handling so I’m likely to bounce back and forth between these two for a while until I’m happy.

That’s all for now. Rather than go through a long delay between posts again, I’ll try to post as regularly as possible with updates on what I’m working on at the time. Even if the post is short, I’ll try to put in some details of the development process for you to read.

If you enjoy this sort of post, please let me know! Feedback helps me work out what people enjoy reading and hopefully write better posts in the future. Thank you for reading, everyone. 🙂

It Lives!

With some back-end and core actions out of the way, it was incredibly satisfying to watch the quest system spring into life today. The two bootstrap quests are now launched with a new character. They don’t do much more than popup messages right now, but everything starts somewhere.

The work from here is “just” building out all the remaining actions and conditions for quest scripting. I say “just” because it’s still a huge amount of work. But it’s finally starting to feel like I’m getting somewhere!

If this doesn’t look like an awful lot of progress for a few months work, remember it’s a black triangle milestone. This is a pioneer of more interesting stuff to come.

Questing Part 3 – Anatomy of a Task

Example custom quest action created for this post

The quest system back-end is coming along. I’m sad it’s not further along by now, but life has a way of disrupting plans. The important thing is I’m still making progress and have some good stuff to share today.

In this post, I will dissect tasks along with their conditions and actions, which together form the meat of a quest. There’s a great deal of technical content ahead, I want this post to be a kind of primer for contributors to quest system. My apologies to those of you who don’t enjoy code-heavy updates.

Before getting started, please have a quick skim through Donald Tipton’s excellent documentation for his Template v1.11 quest compiler/decompiler. As discussed in Questing Part 1: Source, these source files are also used by Daggerfall Unity’s quest parser so we have common ground with classic. This even allows quest source to be shared back and forth with classic for testing. I’ve actually rolled back some of my ideas from that first post and will use Template source files directly as-is without any changes. This might have to change in time but right now I’m aiming for total parity.

If you’d like to see some real quest source, you’ll find all of Daggerfall’s decompiled quests in the StreamingAssets/Quests directory (link to GitHub, ignore .meta files). But today we’re just zooming in on tasks and actions to see how these are handled by Daggerfall Unity.

 

Tasks

Daggerfall quests have four distinct forms of tasks (so far). All of the examples below are from the quest _BRISIEN.

Standard – This is a basic task which does not start unless explicitly triggered somehow. The task name (e.g. _invitepc_) is also a boolean symbol which can be queried to see if task has been triggered (i.e. is active). The lines under the task header are the conditions and actions making up that task.

_invitepc_ task:
	start timer _remindpc_ 
	give pc _letter1_ notify 1026 
	create npc at _dirtypit_ 
	place npc ladyBrisienna at _dirtypit_ 

Repeating – These tasks execute continuously until the symbol they reference (the boolean state of another task or variable name) is triggered. In below case, the task will persist until _exitstarter_ is triggered. Repeating tasks appear to be triggered automatically at startup.

until _exitstarter_ performed:
	start quest 999 999 
	start quest 977 977 
	start timer _invitepc_ 
	remove log step 0

Variable – A variable is really a kind of task with trigger state only. Trigger state may be set/unset by other tasks.

variable _exitstarter_

Headless – Every quest must have a single headless task. This is the entry point to be executed automatically at quest start-up. Unlike other tasks, a headless task does not have a symbol to query trigger state. It just executes to bootstrap the rest of quest. This is the entry point of _BRISIEN:

--	Quest start-up:
	log 1010 step 0 
	pc at PiratesHold set _exitstarter_ 
	say 1025 

At time of writing, Daggerfall Unity will parse through quest source to instantiate tasks and try to match component actions to a registered template (more on this below).

 

Conditions

Other than being triggered at startup or by other tasks and clock time-outs, a task can have one or more conditions that might cause it to be triggered. For example, if player is in a specific place at a certain time (e.g. Daggerfall at night) then some action can be performed (e.g. play the “vengeance” effect). This makes it possible to chain together tasks which trigger on and off based on the trigger state of other tasks.

I won’t go much into conditions right now as they have not been implemented yet. I’ve just barely stubbed out a bit of starting code that will be replaced later. If you like, you can read more about quest conditions here.

 

Actions

A quest action is a bit of text that does something. This is usually a single thing like playing a sound, displaying a message, or starting another task. Don’t think of actions like a normal programming command though. They aren’t necessarily run and done (although they might be). Try to think of actions as components attached to a task in a similar way that Unity components are attached to a GameObject. This isn’t a perfect analogy, but its a start. Like GameObjects in Unity, tasks can switch on and off and their component actions perform bits of work over time.

Actions are a great way for contributors to help build out the quest system. There are many different kinds of actions, some will be very simple others very complex.

 

Building Actions

So how does an action go from a line of text to actually doing something in the game? The rest of this post will cover the fundamentals and show a real working example of a custom action… in action.

The bones of every action begins with the ActionTemplate class, an abstract implementation of IQuestAction interface. All actions must inherit from ActionTemplate and implement the required parts of IQuestAction. This ensures that every action template has a few key features:

  • Pattern – A regex string used to pair a line of source text with this action. Two actions cannot have the same match pattern.
  • Test – Checks if provided source string matches the regex pattern expected for this action.
  • Create – An action template is special in that it can also factory (i.e. generate) a new instance of itself with default settings. This allows the QuestMachine which hosts active quests to hold a list of self-replicating action templates that can be instantiated as required.
  • GetSaveData – Gets a data packet from action live state. This will be passed on to JSON serialization system when saving a game.
  • ResoreSaveData – Sends a data packet to action from serialized state. This will be used to restore action state when loading a game.
  • Update – Called by the task owning this action. Allows the action to do work every frame as needed.

To show all of this working, I wrote an example called JuggleAction which simulates the player juggling some number of objects with a percent chance to drop one. Click here for the full source code and I’ll break it down below. Let’s start with the pattern:

public override string Pattern
{
    get { return @"juggle (?<numberOfThings>\d+) (?<thingName>\w+) every (?<interval>\d+) seconds drop (?<dropPercent>\d+)%"; }
}

This is just a basic regex match string that looks for a pattern like “juggle 5 apples every 2 seconds drop 40%”. Everything the action needs to execute is contained in the pattern. Sometimes an action might take different forms and the pattern string must cover these variants also.

The parser uses Test to find a registered action template with pattern matching source. When a match is found, the JuggleAction template will factory a new instance of itself with default settings by way of Create.

public override IQuestAction Create(string source, Quest parentQuest)
{
    // Source must match pattern
    Match match = Test(source);
    if (!match.Success)
        return null;

    // Factory new action and set default data as needed
    JuggleAction action = new JuggleAction(parentQuest);
    action.thingName = match.Groups["thingName"].Value;
    action.thingsRemaining = Parser.ParseInt(match.Groups["numberOfThings"].Value);
    action.interval = Parser.ParseInt(match.Groups["interval"].Value);
    action.dropPercent = Parser.ParseInt(match.Groups["dropPercent"].Value);

    return action;
}

You’ll notice the action parameters are exposed directly by the Match class returned by Test. This makes it easy to read out the values involved. At this time, our new action is ready and is added to a collection stored in the Task object. During quest runtime, the task will call Update on each action to do the work required. Here it just counts off time and if still holding any objects, calls the Juggle() method. Note that we’re using Time.realtimeSinceStartup instead of Time.deltaTime. The reason for this is that QuestMachine ticks at a slower rate than Unity (currently 10 times per second). So we need to measure time without using something that only changes frame-to-frame.

public override void Update(Task caller)
{
    // Increment timer
    if (Time.realtimeSinceStartup < nextTick)
        return;

    // Juggle 'em if you got 'em
    if (thingsRemaining > 0)
    {
        Juggle();
    }

    // Update timer
    nextTick = Time.realtimeSinceStartup + interval;
}

Below is the Juggle() method for completeness. It just spits out some notification text to HUD and randomly decrements object count until none are remaining.

private void Juggle()
{
    // Juggle current things
    DaggerfallUI.AddHUDText(string.Format("Juggling {0} {1}...", thingsRemaining, thingName));

    // We might drop something!
    int roll = Random.Range(1, 101);
    if (roll < dropPercent)
    {
        thingsRemaining--;
        DaggerfallUI.AddHUDText("Oops, I dropped one!");
    }

    // Give up if we've dropped everything
    if (thingsRemaining == 0)
    {
        DaggerfallUI.AddHUDText(string.Format("Dropped all the {0}. I give up!", thingName));
        return;
    }
}

I won’t touch on GetSaveData and RestoreSaveData yet as quest state serialization has a ways to go. You can check the full source of JuggleAction linked above for an example implementation.

You might recall I said something about registering new actions with QuestMachine. This might change later, but right now our action class JuggleAction is registered in QuestMachine from RegisterActionTemplates() like below. The template is only being used as a factory so it doesn’t need to pass in an owning quest at construction.

RegisterAction(new JuggleAction(null));

Registering the action template allows the quest machine to find it (using Test) and factory a new instance from the template.

Now that we have an action and registered it to quest machine, we actually need a quest that uses this action for real. I created a cut-down quest just for this example called __DEMO01.

- Minimal example quest used to demonstrate how to script custom actions

Quest: _BASIC01

QRC:

- No text resources

QBN:

- Headless entry point with custom action
juggle 5 apples every 2 seconds drop 40%

All that remains is to instantiate the quest itself. I will add a console command soon for this, but in the meantime I’m calling the following bit of code from StartGameBehaviour.

GameManager.Instance.QuestMachine.InstantiateQuest("__DEMO01");

This loads our custom quest into the quest machine and starts executing supported actions, which right now is just the demo quest and juggle action. When starting a game, this will be the output:

 

Next Steps

For now, I will continue to work on the quest machine, parser, and related frameworks. My immediate next step will be to get the full tutorial quest working along with some foundation conditions and actions, and a few supporting user interfaces (quest log, quest debugger UI).

I would like to invite the more experienced contributors to review the quest source documentation in more detail and see if any actions might fall into their range of interest. I would also love some help with quest resources other than tasks (e.g. Place, Item, Foe, Person, etc.). I’ve stubbed out the Clock resource as a starting point. If there is something you would like to work with, please start a conversation on the forums and let’s see where it takes us.

If you have any questions or would like to dicuss this post in more detail, please don’t hesitate to find me on the forums!

 

For more frequent updates on Daggerfall Unity, follow me on Twitter @gav_clayton.

Back To Work 2017

Hey everyone, belated happy new year for 2017!

I’m back to work after taking a few weeks off. Now things have settled down, I’m also back to working on Daggerfall Unity’s quest system. You can expect a blog post for part 3 of this series soon.

Quests are the beating heart of Daggerfall, everything from the tutorial to vengeance! are powered by quests, and this will be my main focus in 2017 until things are working well enough to move onto spells and effects. With a bit of help from others this will come together at a reasonable speed. Just to manage expectations, you won’t see a fully-formed quest system arise out of nothing – things will continue to be built in small stages. But barring any major setbacks, you should be able to launch quests for testing with the quest debugger by March-ish. I can’t promise every part of quests will operate (in fact, I guarantee it won’t) but it should be enough for testers to sink their teeth into and iterative development will continue from there.

Speaking of help, I’m also looking forward to seeing what contributors and modders do in 2017. I think last quarter saw the most number of new contributors since Daggerfall Unity began in August 2015. This is really exciting for me because it confirms opening source from the beginning was the right choice. There will probably come a point where the project will be taken further by others (and probably faster) than I could take it by myself. If things keep heading the way they did in 2016, this should be a big year for Daggerfall Unity.

 

December 2016 Test Build

Hello everyone! This will be my last post for 2016. It’s been a great year for Daggerfall Unity with solid updates across the board. I was hoping to have basic quest support in by now, but sadly not everything goes to plan. This will return as a priority early in 2017 so watch this space!

One thing that always amazes me is the quality of work this community is willing to put back into Daggerfall Unity. It’s always a pleasure to find a new pull request on git from someone willing to contribute their personal time to make this project even better. So this post is going to focus almost exclusively on contributions from community members. It’s time for kudos and credits all around, and you’ll see very little of me this post.

 

Texture & Mesh Replacement

This feature began with Uncanny_Valley and has lately been updated and maintained by TheLacus. It allows for runtime injection of new textures and meshes into Daggerfall Unity’s scene builders, setting the stage for updated models, higher resolution materials, and improvements to Daggerfall’s vanilla UI. It’s still early days but the potential is incredible. Here’s a few screenshots of new assets by community members.

 

At time of writing, mesh and texture replacements aren’t quite ready for download. But now support for this is baked into the core, you should start seeing community-created packs in the near future. You can read more about mesh and texture replacement in this thread on the forums.

 

Early Bow Combat

New contributor electrorobobody added basic bow combat to the lineup of supported weapon animation. No counting arrows yet, and you’ll need to roll a new character for your free silver bow, but it’s awesome to finally burn down enemies with ranged kiting. Looking forward to bows becoming a strong part of the game in future.

 

Save & Load Weather

Daggerfall Unity added basic weather events a while back, but they would not be saved and loaded with your games. Thanks to midopa, the current state of weather will be saved and loaded. This will only get better once correct weather events are wired up based on climate and season.

 

Enemy Steering

Another epic update by midopa. He added a little steering to enemy AI to prevent enemies from stacking on top of small creatures like rats. As hilarious as this problem could be, it’s good to see a workable solution for this bug. It’s still possible for enemies to slightly stack in edge cases, but the problem is much improved and they will no longer ride around on each other (imagine skeletons surfing rats and rat-rat-rat stacks).

 

Potion Recipes

The perennial InconsolableCellist returned with some amazing updates for us. Credit goes completely to him for working out potion recipe format and integrating with Daggerfall Unity. This also means potion recipes will display properly in inventory, and they’re even usable to see the individual ingredients. This is really important ground-work for a bunch of other things down the line.

 

Books

I wrote the initial book reader UI ages ago, but InconsolableCellist wrapped it up along with random book drops in loot, correct tooltips, and all-round awesomeness. Books currently exhibit the same formatting problems as classic (because it’s the same book data). That’s something yet to be fixed.

 

Exterior Automap

Nystul has done it again with the perfect companion UI to his dungeon and interior automap. Yep, exterior automaps are now a thing! It even supports proper tagging of buildings, zoom, and rotation. As always, I’m completely blown away by how complete this is right from the start. It’s still waiting on full building name integration and building identification in scene, but that will come. For now, all the buildings are tagged by type. Go explore!

 

Spotlight: Allofich

I can’t give Allofich high enough praise. He has worked incredibly hard tuning up different areas of Daggerfall Unity to make it more true to the original. He fixed a wide range of UI problems, identified sound effects, linked sounds to their correct actions, fixed clothing and item problems, and so on. Check out his full list of commits here. It’s hard to show these off properly in screenshot form because the changes are either subtle improvements or related to audio, but below is one of the UIs he has cleaned up. Note the poor texture joins in the “before” image (circled). Huge props to Allofich for his work!

 

Thanks To: AnKor

OK this is embarrassing. I was looking everywhere for the animations used when player was riding horse or cart. These turned out to be in the overlooked CFA image file format. Somehow, I had completely disregarded these files which are a format holdover from Arena. Yep, I’m only human. Fortunately, AnKor pointed this out on the forums and I was able to implement CFA support in no time. Now we have this:


It’s only a short jump from here to having these transport options in the game.

 

Thanks To: Testers

I also want to send out a huge thanks to all the amazing people who tested Daggerfall Unity in 2016 and reported the bugs and problems you found. There are simply too many people to list, but you know who you are. You’re on the forums, and Twitter, and Reddit, and sending me emails. You guys rock!

 

Bugs and Problems

Yep, we got ’em! Any large update like this will bring its fair share of new bugs. If you come across a bug during tests and would like to report it, please lodge this in the Bug Reports forum. Don’t forget to read the Guidelines to help you provide the best information to developers.

Contributors, please keep an eye on the Bug Reports forum for anything that might fall into your wheelhouse.

 

Where To Download?

You can always download the latest version of Daggerfall Unity from the Live Builds page. If this is your first time downloading Daggerfall Unity, welcome! Other information on Live Builds page should also help you get started. If you have any troubles, or just want to discuss updates, please go to the December 2016 Test Builds Updated thread on forums.

 

That’s it for 2016! Thank you everyone for visiting and all your kind words of support. Here’s wishing you all a very Merry Christmas and Happy New Year, and all the best for 2017!

 

For more frequent updates on Daggerfall Unity, follow me on Twitter @gav_clayton.

Questing Part 2 – Compiling

In the first part of this series, I discussed how I’ll be using source files output by Tipton’s Template v1.11 for quests in Daggerfall Unity. If you’d like to check these out in full, the quest source files are already on GitHub. Follow this link to view them (ignore the .meta files).

Some interesting quest files to investigate are:

  • _BRISIEN.txt – This is the quest that launches when player starts in Privateer’s Hold. It sets the whole story arc in motion and starts timers for delivering letters that prompt player to visit Lady Brisienna. Failing to visit Lady B in time is ultimately a failure condition of main quest.
  • S0000999.txt – Starts when you leave Privateer’s Hold. Delivers letters from Prince Lhotun and Morgiah and sets key global variables.
  • S0000977.txt – Also starts when leaving Privateer’s Hold. Sets up regular ghost and wraith spawns in Daggerfall and plays the VENGEANCE! sound.
  • TUTOR.txt – Is the tutorial quest started when selecting Yes to the prompt at start of game.

As another interesting tidbit, longtime players may have noticed the initial journal entry that begins with…

"I am on a mission from the emperor to investigate
the shade of King Lysandus. His spirit has been
haunting the city of Daggerfall. The emperor
himself has charged me with the duty of laying
his ghost to rest."

…will stick around in your log forever. Even after you’ve completed the game, this first journal entry will remain. As part of researching the quest system a while back, I looked into why this was happening and found the above journal entry is added twice and removed only once. The below image sums it up visually. You may have already seen this when I posted it to Twitter back in September.

 

questlogmessagestuck

So the quest system in Daggerfall is quite powerful. It’s responsible for adding and removing journal text, starting timers, delivering letters, spawning enemies, playing sounds, setting global variables, moving NPCs, and a slew of other functions. At first blush it can appear a lot like a full programming language, but it’s only superficially so. The structure is actually more like a complex INI file, or even a kind of markup file. Everything is neatly categorized into its own section and execution flow generally only happens in a few different ways. Most commonly are at startup, when a timer ends, and due to a variable or condition changing state.

Thus despite the initial similarity to a programming language, the quest source is really just a collection of defined objects with some very basic scripting functions. Most of these functions revolve around spawning something, starting something, playing something, or changing something. Complex enough to get the job done, but don’t feel like you need to be a programming expert to create new quests in the future. Using Tipton’s Template v1.11, you could even start creating quests in classic Daggerfall now and later port them into Daggerfall Unity.

Likewise, the job of compiling the quest source back into Daggerfall Unity is not that difficult. It’s going to have some challenges, but nothing on the scale of building a real compiler, something I thought I’d be facing at the outset. The problem is largely just splitting source file up into correct parts and handing that source off to classes designed to support that part. For example, messages will go to a Message class, timers will go to a Timer class, etc. When serializing live quests as part of save games, the QuestMachine will save/load JSON state for each live quest along with the global variables for the current game.

To help Daggerfall Unity re-compile Template’s source output, I’m going to make some minor changes to the expected source files. I’m trying to keep these changes to an absolute minimum.

First change is for the quest header to be uncommented in source file. For example, _BRISIEN has the following header. The dash ‘-‘ prefix starts a comment.

-- StartsBy: letter
-- Questee: anyone
-- Repute: 0
-- QuestId: 0

This reason this can be commented out is that Template is designed to re-compile quests back into the original QBN/QRC format. When commented out, Template will just use the information already in the quest QBN data. However, Daggerfall Unity relies entirely on the quest source and will need the above uncommented to:

StartsBy: letter
Questee: anyone
Repute: 0
QuestId: 0

This way the information can be parsed back into the quest data at compile time.

The second change is that I would like an explicit startup task, rather than an implicit startup after the QBN object definitions (like Person, Clock, etc.). Currently the startup task looks like this:

-- Quest start-up:
log 1010 step 0 
pc at PiratesHold set _exitstarter_ 
say 1025 

I would like to change this to:

startup:
log 1010 step 0 
pc at PiratesHold set _exitstarter_ 
say 1025 

This makes the startup task an explicit task object to be executed when quest begins. This is already the current behaviour, but I think this change makes the task clearer to identify for both quest creators (even without a comment) and for my compiler. I could definitely get away without this change, but I prefer the explicitness to the current setup.

And of course, the above is subject to change as the quest system matures. If I learned anything from rolling out items, the feature will probably look different again by the time it’s mostly complete. Daggerfall Unity is not just a game remake, it’s an ongoing research project into the guts of Daggerfall. That adds a few twists outside of normal gamedev process, and I just need to roll with it.

One of the upcoming features not shown yet is the quest debugger currently in development. Hopefully, I will have something to show on this by part 3. The quest debugger will be used to manually start new quests, terminate and restart executing quests, and inspect state of global variables and quest objects. It’s a big UI that will continue to grow as development progresses. Should turn out to be quite useful though.

 

For more frequent updates on Daggerfall Unity, follow me on Twitter @gav_clayton.

Questing Part 1 – Source

With items and loot more or less finished, it’s time to place my sights on the next big feature group. I had originally planned to work on spells and effects in the 0.4 cycle, but also had quests in mind as an equally important feature. So back in July, I used a Twitter poll to sample what the community wanted priority on. The answer came firmly in preference for quests over spells.

Fast forward a couple months: 0.3 stable is now tagged on Live Builds page and I’ve started work on the quest system in earnest. This post is the first in a series documenting the journey from raw bytes to a working feature.

When adding a big new feature, there’s always a technical planning stage before commencement. I need to understand which of Daggerfall’s binary files are involved in the feature, learn how much is already known about those files (sometimes a lot, sometimes almost nothing), map out the additional details I need to know before I can re-implement that feature, and finally start cutting some code.

Sometimes it takes a few iterations, as writing code to pull apart the binaries is itself a journey where new information is learned. I don’t know what I don’t know, and often that new information results in a new iteration with better understanding. There’s basically a research-implement-compare loop going at all times throughout development of Daggerfall Unity. It can be a bit draining.

Items for example needed considerable research to bridge the gap between “enough knowledge to make an item editor” and “enough knowledge to fully implement items in a new engine”. Believe me, there’s a huge amount of work needed between having a file spec with lots of unknowns and building a completely functional equivalent. Most of my time is spent somewhere in that gap.

So when starting quests, I set out to learn everything I could about the binary formats and the work others had done before me. I was pleasantly surprised to learn:

  • Quests are among the most well-understood formats, thanks to the work of several early Daggerfall hackers (notably Donald Tipton and Dave Humphrey).
  • Tools exist to edit live quests, but more importantly decompile the QRC and QBN files to a human-readable source file (thanks to Template v1.11 by Tipton).
  • Early Daggerfall modders already had a good understanding of creating quests for Daggerfall – there’s an established process.
  • Quest files are one of the few cleanly decoupled things in Daggerfall. Unlike items which have template data hard-coded in the executable, quests are nicely self-contained.

With the above in mind, it was no longer necessary for me write a quest decompiler from scratch, design a new file format, decouple quest data, or chase half a dozen other time sinks. I can almost go directly to implementation. Almost. But first I need quest data in a usable form.

For the first step, I’m using Template v1.11, which you can find on UESP. This tool can decompile all the QRC (quest text) and QBN (quest programming) files to a single easy-to-read text file. So the information goes from raw binary data to the following (snippet from starting quest _BRISIEN).

QBN:
Item _letter1_ letter used 1020
Item _letter2_ letter used 1021
Item stopMainQuest letter used 1022

Person ladyBrisienna face 1 named Lady_Brisienna anyInfo 1012 rumors 1013

Place PiratesHold permanent PirateerHold1
Place _dirtypit_ remote tavern

Clock _invitepc_ 7.00:00 14.00:00
Clock _remindpc_ 30.00:00 0 flag 1 range 0 1
Clock _pcfailed_ 14.00:00 0 flag 1 range 0 1
Clock _oneday_ 1.00:00 0 flag 1 range 0 1
Clock _nowwhat_ 29.09:00 0 flag 1 range 0 1

-- Quest start-up:
 log 1010 step 0 
 pc at PiratesHold set _exitstarter_ 
 say 1025

That can still look a bit daunting if you’re not comfortable with programming concepts, but the source format generated by Template v1.11 is generally very easy to read and understand – more like a complex INI file than a real programming language. It’s so good that I’ve decided to adopt Template’s output as the source data for quests in Daggerfall Unity. You won’t need to recompile quest source back to QBN/QRC, rather you will use the source directly in Daggerfall Unity where it will be compiled at runtime by the quest system.

This means the de facto standard for creating Daggerfall quests will remain essentially the same in Daggerfall Unity (with some minor differences I’ll discuss later). If you’ve ever created a quest for Daggerfall, or even seriously looked into it, then you already have the skills to create quests in Daggerfall Unity. If you’re new to Daggerfall quests then you can learn from existing quests and read Template’s excellent documentation. Just as I don’t need to start from scratch, neither do you.

I will need to change the format slightly for unique needs on my side, but I aim to keep my input format as close as possible to Template’s output format. There’s also the need to emulate support for every single condition and action in Daggerfall Unity to behave similarly to Daggerfall given the same quest source. That will probably be an ongoing process all the way through to 1.0. But we need to start somewhere, and this is a great starting point.

The next article in series will look at parsing quest source files and how quests will be executed inside Daggerfall Unity.

 

For more frequent updates on Daggerfall Unity, follow me on Twitter @gav_clayton.

Tutorial – Cloning from GitHub

If you’re interested in developing mods or contributing to Daggerfall Unity, you’ll first need to clone the project from GitHub. This light tutorial goes through the basic process of cloning Daggerfall Unity using GitHub for Desktop and opening with a fresh Unity install. There are many other ways to clone from git, but this is probably the simplest if you’re new to Unity or open source repositories.

After cloning the project, I go for a quick run through Privateer’s Hold to check everything is working normally.

Standalone Builds Update

After launching Live Builds a week ago, I’ve been very happy with the ability to push out small incremental changes. Besides the streamlined build process and less of a wait time, it also means I’m not overwhelmed with bugs every release. I can now tackle large problems fast and keep track of smaller problems for when I have the time.

This ability to turnaround builds so quickly has lead me to rethink the standalone builds (for now) and continue with the leaner, more agile cloud build process. I will revisit the standalone builds later in Daggerfall Unity’s life cycle. Here’s a summary of how to get Daggerfall Unity moving forwards:

  • GitHub always has the most recent code for developers.
  • The Live Builds page always has the most recent builds, and links for getting Daggerfall.
  • I will start to tag specific live builds as “Stable”. This means that everything implemented so far is generally working as expected.
  • I will restore the Daggerfall Tools for Unity pages as soon as possible, including updated tutorials.

If you were waiting for the convenience of a standalone build, I apologise for changing my plans. Daggerfall Unity is very much a living thing, both in terms of development and community, and can take up a large amount of my personal time. Anything that saves me time I can put back into gameplay, or spend with my family, is extremely valuable to me.

The good news is that pointing Daggerfall Unity to your game files has never been easier. The setup helper introduced with version 0.2 makes it very easy to get up and running, and you only need to download the game files once.

The first 0.3 stable build will be tagged soon. Lootable monsters just went into the latest live build and is with testers now. I only have the Rest and Keybind UIs to go and I’ve hit all the feature milestones planned for this release.