Attunement Arena – Air Currents

Attunement’s Air Currents

Edit: Attunement Arena has since been renamed Attunement: Power of the Gods

A 3D Versus Elemental Brawler

Three Dimensional Math

The simplest math from the Orange Book (Realtime Collision Detection)

The simplest math from the Orange Book (Realtime Collision Detection)

In order to accomplish the gameplay goal here, I used Closest Point to Segment 3D math.

A step by step of the process is available here:

  1. This was accomplished by using a 3D problem simplified to 2 dimensions.
  2. For each segment of the air current, evaluate as follows.
  3. Evaluate the vectors for the start and end points of the line. We will call this line AB.
  4. Find the closest point on the AB line to the target. We will call this D.
  5. Evaluate the distance between the player and D. If this distance is greater than the player’s radius plus the radius of the current, we’re done.
  6. Evaluate the forces applied to the player and the input applied by the player. If either of these is too great, we want to stop so the player can leave or be knocked from a current.
  7. Create a vector that points along AB but points slightly towards the center of the current so the player can ‘settle in’ to enjoy the ride.
  8. If the player is at the start or end of the current, apply slightly different logic. Near A, behave normally. Near B, dont pull to the center of the current (or the end current can get frayed and fling you across it instead of behaving like a air spout)
  9. If the player is affected by the current, negate their current velocity and disable the effect of gravity upon them.
CODE: Air Current - Check Current Segment


The end result of the behavior is as follows:

An elementalist can enter a current from any point. If the player enters the current, they cease to fall and are ferried along the current from each segment to the next.

If a player inputs commands to their character to move, the force of the current is overridden allowing the player to fall or leave the current easily. Similarly, if the player is affected by any significant force (external forces are tracked and decay quickly), the current ceases to negate falling/current velocity, allowing the player to be thrown from the current.

The basis of this 3D math was provided by the amazing Orange Book: Realtime Collision Detection

Visual effect

This was done by using circular meshes emitted in the same direction.

Parts of the scripting set the particle velocity and lifetime based on the distance to the next node.

Game Implication

The gameplay implication of this is that it provides players a tool to quickly move around the game environment.

One of Attunement Arena’s design goals is to provide high degrees of player movement. A design problem that quickly emerges is the characters can move too fast for players to track what is going on.

A way to solve this issue is to reduce the base movement speed and to provide powerful and fast movement tools. The caveat is that the player won’t always be using the movement tools. This results in a contrast of movement speeds for the player, which make the faster movement feel more enjoyable. The additional benefit is that when a player is moving slower, they are a more vulnerable target allowing for depth of skill in the play-counterplay department.

Thank you for reading.

 

Post Edit: Check out more info on the Attunement: Power of the Gods blog.

Citation

Ericson, C. (2005). Realtime Collision Detection. San Francisco, CA: Elsevier.

Bun & Games – Bunny Heaven v1.06

BUNNY HEAVEN

Managed on Github

[Chrome Users: Webplayer support was recently removed from this browser. I am working to get a WebGL version for this project soon.]

[unity src=”935″]

There are two main controls: Movement (clicking or dragging) & Spacebark.

[You NEED Unity Webplayer to run this]

This image shows basic gameplay. Note the 60+ FPS & only 7 draw calls. Only one draw call is to display the bunnies.

This image shows ~500 animated bunnies. Note the 60+ FPS & only 7 draw calls. Only one draw call is to display the bunnies.

Let’s talk about Bunnies

About three weeks ago, I made a Bunny Heaven Dev Blog about a recent game jam project – Bunny Heaven.

It wasn’t much of a game. It had little interactivity. You could move a dog around chasing cute animated bunnies. The project’s merit is in how I misuse Unity’s default particle system to render 1000 adorable animated bunnies in one draw call.

Recently, work is renewing on this project! This blog post is a log of my thought process on how I utilize the particle system.

Bunny PArticles

From the bottom of Unity's Particle System inspector view.

From the bottom of Unity’s Particle System inspector view. (This image is slightly out of date.)

Unity’s default particle system allows for some limited animation options. You are limited to one material and forward playing animation at a constant rate.

This would simply not do. I had a very particular purpose in mind. I wanted to display a great quantity of bunnies to the screen at once. The most effective way to do this was to avoid GPU bottle-necking myself. Particle Systems typically involve very few draw calls as they let a single shader draw all the various particles.

This was the beginning of Bunny Particles.

From there, the bunnies needed to animate and move in different directions. I accomplished this with a technique I’m calling Epoch Locking

Epoch Locking

According to Google, an epoch is

“the beginning of a distinctive period in the history of someone or something“

In this instance, an epoch is the moment a particle is locked into in order for it to display an appropriate animation.

This is the origin of my term, Epoch Locking.

How to Epoch Lock

  1. Unity’s particle system animates linearly (according to the curve I have set in the image above).
  2. Unity’s particle system allows manual editing of individual particles.
  3. Unity’s manual particle access allows you to change the age of a particle.
  4. A material sprite sheet can contain frames of bunny animation, even different directions.
  5. By checking the direction particles are moving you can access the most appropriate animation to use. You can save the direction an individual particle is moving in a CPU side array.
  6. Finally, you can manually set the age of that particle to the appropriate time interval to display the animation appropriate for it’s current velocity.
    • If the age drops out of that appropriate epoch, you reset it to the beginning of that time period.
    • If the age is too young, you can set it to the beginning of the epoch.

An early mistake I made with my approach was using an incorrect size for the sprite sheet. It is ideal if the sprite sheet is pixel perfect, meaning that the pixels line up with the pixels of the sprite.

Additionally, I recommend about nailing down the formula appropriate for your epoch period calculation.

You’ll need both the min age and the max age for each individual particle based on how many times the animation will cycle and how many frames you will cycle it through. If the starting lifetime of a particle is high, and the particle cycles through the full animation sheet (even though we never let it), the animation will be faster. You will have to do math in order to achieve your preferred animation speed.

Finally, my current code:

BunnyParticleEpochLocking

If you want more rigorous look at how to Epoch Lock, check out Github – Bunny Heaven.

Modified Animation Rates

There is an unmentioned sub-topic within Epoch Locking here. What if we want different bunnies to animate at different rates?

For example, a bunny is quickly running away from the dog. It should animate more quickly than a bunny that is idly hopping along.

To accomplish this we need to adjust the remaining lifetime of particles each frame. We can modify their lifetime based on the magnitude of their velocity. When a particle is moving quickly, it will age more quickly. Faster aging means faster animation.

BunnyParticleAgeAdjustment

Not Quite an Idle Game

Bunny Heaven’s design is moving in the direction of an idle game.

In the most recent development, I added a point counter that will accrue as the player interacts with the game. The game will have no lose state and allow the player to purchase different ways to interact with the game. However, these new modes of play won’t give exponentially greater points, they will just allow the player more ways to have fun.

This portion will change depending on feedback, but the goal is a no-stress environment where you can interact at your leisure.

Closing Words

The most rewarding part of working on this has been handing my phone to people for them to say “This is stupid” and then proceed to play for another 3 minutes after they felt it wasn’t worth their time.

Forrest has expressed interest in publishing an early version of the game on the Google Play Store. The game would most likely be free and shareable.

 

Thank you for reading,

If you have any thoughts or comments, feel free to reach out!

Ataraxy – April 29th Build

April 29th Build V2.8

[Chrome Users: Webplayer support was recently removed from this browser. Due to this being an outdated build, I will focus on getting the up-to-date build working first.]

[unity src=”924″]

Use the full screen button ^

Submit Feedback
[contact-form-7 id=”789″ title=”Ataraxy Feedback!”]

Terrain Generation

This version introduces new life to the island generation. It improves my architecture for supporting more varied and interesting terrain.

Clusters

There are four types of cluster

  • Biome
    • Features floating islands of various materials randomly placed in one of three approaches
  • Rare
    • Hand-crafted islands with a theme or purpose in mind. In later versions, they will be far less common than normal biomes.
  • Boss
    • Will contain a powerful difficult enemy the player must overcome.
    • Denoted by a large red ‘warning’ zone around the cluster.
    • [Currently, no bosses are implemented.]
  • Landmark
    • Generated next to a normal biome cluster at an uncommon frequency.
    • Serve as visual anchors and to build visual interest.
    • [Currently there are only graybox landmarks.]

Island Generation

There are now three approaches for creating islands within a biome cluster.

  • Poisson Disk Sampling
    • The standard approach in previous versions.
  • Grid
    • A grid of islands with varying subdivisions & misalignment.
    • Creates simple horizontal battle areas.
  • Layered Poisson
    • Begins with standard Poisson approach and places duplicate islands above generated ones.
    • Increases vertical interest.

Cluster Inheritance

Clusters of islands now inherit attributes from their neighbors on generation.

  • Danger Level
    • Based on neighbors, influences how many encounters are within the cluster.
    • Higher danger level results in darker random materials.
  • Island Materials
    • Will not inherit materials from neighbors with harsh danger level differences.

UPCOMING DEVELOPMENT

  • Terrain Generation Improvements
    • Non-Graybox landmarks
    • Bridges?
    • Return of tilted platform?
    • More island generation approaches
  • Pathfinding bug fixes
  • Loot system revision
  • Bosses?

Thank you for reading and playing!

Unity WebPlayer Dead on Chrome: Moving Forward

Dear Unity Developers

If you did not know, the Unity WebPlayer plugin will no longer work by default for Chrome. Source

For better or worse, this change has happened and you can delve into why it happened elsewhere.

This post is about how you can get your content (portfolio pieces, projects, etc) back online.

This thread is about how you can get your portfolio pieces back and view-able on Chrome. If you’re old webplayers aren’t view-able on chrome, that can discourage people from testing your game or project out. We want to get that fixed.

RE-ENABLing NPAPI

It is possible to re-enable NPAPI (the old API that let the Unity Webplayer work on Chrome.)

You shouldn’t expect an end user to do this for obvious reasons: It requires your users to dig into hidden settings & enable things Chrome deliberately displays as dangerous and scary (because they are dangerous & scary.) Most users will immediately balk, leaving your content and possibly your webpage.

Take a look at the warnings at the top of the page where this option lies:

NPAPI

If you desire to re-enable this for your personal use, proceed as follows:

  1. Open Chrome
  2. Go to chrome://flags/
  3. Scroll & find ‘Enable NPAPI’

ZIP Distribution

A second plan of approach: a downloadable zip

This second option is still not ideal. Not everyone is willing to download a ZIP or RAR. Depending on the state of your website, chrome sometimes will go nuclear declaring malicious file warnings. You ultimately want to provide the path of least resistance to others if they are to test your game. Downloading takes time & trust that will dissuade some visitor.

To go about this approach:

  1. Set your Unity build settings to Mac or PC Standalone.
  2. Build your project.
  3. Zip your project up.
  4. Upload to Dropbox, Google Drive or distribute USBs by Carrier Pigeon.

WEBGL – The future?

A third option is to use Unity 5 & the new WebGL Preview build option.

In order to do this, you need to have Unity 5 installed. If you wish to continue using Unity 4 for development, you can maintain multiple installations of Unity on one computer. The downside is you will need to upgrade the project each time you want to build.

Upgrading Steps:

  1. Install Unity 5 (Unity Personal is free to most users)
  2. Backup your project or create a second project version.
  3. Upgrade your project to Unity 5.
  4. Pay attention to the upgrade progress for errors.
  5. Build to your previous project target
  6. Test your project.
  7. Fix any errors created from upgrading
  8. Prepare to build to the WebGL Preview target.

UPGRADE ISSUES

Upgrading older projects to Unity 5 comes with some small inconveniences in the form of upgrading errors or behavior changes.

I ran into several upgrading different projects but google turned up some easy answers. I’ll aim to keep this list updated with the non-project specific problems I find.

There might be some behavior changes within your project. Of the two projects I upgraded, I encountered some minor changes. Make sure to test your project!

BUILD SETTINGS

WebGLPreview

Once you get your project up and running with Unity 5, now comes the WebGL (Preview) steps.

  1. Select the ‘WebGL (Preview)’ option near the bottom of the Platform list.
  2. Click ‘Switch Platform’
  3. Click ‘Player Settings’ & confirm various typical settings
  4. Determine if you want a Development Build (read below)
  5. Determine what Optimization Level (read below)
  6. Click ‘Build’
  7. Select a target directory
  8. Click ‘Select Folder’
  9. Wait.
  10. Test your built WebGL version by opening the index.html in the target directory.
Development Build

If you plan on sharing your game, you don’t want to create a Development Build. It features non-minimized names & other inefficient approaches to allow for profiler use.

Optimization Level

Your choices here can be summed up like this:

The longer the build, the lower the file size and the lower the load times.

A small side project of mine (Cryomancer) went from 50MB to 30MB by going from Slow to Fast. (Disclaimer: I removed some unused audio, which Unity’s build pipeline should’ve stripped out anyway.)

I have yet to build Fastest (which apparently has the longest build times and should be done for final versions.)

User Faced File

If you’ve gotten this far, it means you have a built version or you’re waiting for it to finish.

I’ll take a moment to talk about the index.html. This index file can be modified and customized to contain things like game instructions, custom borders or even a link back to your website.

When you’re satisfied, hit build and pick a target directory!

You’ll get a different layout than the old WebPlayer html build page.

You will still have an ‘index.html’ that you can customize the contents for if you want to have stuff like game instructions, custom appearance or a link back to your website.

HOSTING

Finally, once you’re done you have a few options for hosting.

your webpage

You might be able to upload this straight to your website (maybe zip it locally, upload it and un-zip it there to speed things up).

This website is a custom wordpress install. I have yet to figure out how to directly embed WebGL Unity builds into posts or pages. If you know of a way or have advice, feel free to let me know.

DROPBOX

An alternative is hosting it on dropbox and providing a link on your webpage.

There is a great post on UnityAnswers that highlights how to do this.

An example link (which should be playable): Cryomancer WebGL on Dropbox

Finally, Facebook or other sites might put up warnings for this type of link, but that could be resolved as they get time to crawl the various pages.

Google Drive

For a Mini-Ludum a few months ago I managed to host a Unity Game on Dropbox. This was back in the days of WebPlayer, but it might be worth looking into.

If I get a chance to try this, I’ll update this post again.

CLOSING WORDS

I can’t speak for the WebGL build’s usability quite yet but it is online and I can link to it on my portfolio! I’ll aim to improve behaviors like full-screening, mouse locking & more in the coming weeks.

I hope that others find this useful.
If you have questions, comments or improvements to this process, feel free to reach out to me.

Ataraxy – April 7th Build

April 7th Build V2.6

[Chrome Users: Webplayer support was recently removed from this browser. Due to this being an outdated build, I will focus on getting the up-to-date build working first.]

[unity src=”877″]

Use the full screen button ^

Submit Feedback
[contact-form-7 id=”789″ title=”Ataraxy Feedback!”]

The past week and a half have been busy and chaotic.

Early Tutorial

Several iterations into the tutorial has provided a good basis for letting players experience the game.

Trying to introduce players to the individual elements of the greater game proves difficult.

This is a better current version as I move my focus back towards environment creation.

Incoming audio

As noted in a previous Dev Blog Post, I wrote an AudioManager for Alex Lobl to use when implementing audio. The AudioManager works as expected and soon the game will feature sound effects and music!

Modifier Fine Tuning

While not visible while playing, I fixed a number of bugs occurring behind the scenes with modifiers.

I tuned some numbers to give a better feel for pacing.

Finally, I provided myself editor controls to give specific enemies specific modifiers when hand crafting context. I used this extensively in the tutorial to have better control when teaching the game concepts.

UPCOMING DEVELOPMENT

  • Terrain Generation Improvements
    • Greater vertical interest
    • Bridges?
    • Return of tilted platforms?
    • Return of landmarks?
  • The all encompassing concept of Loot Orbs is going to be divided
    • Treasure Orbs – Gain a new item!
    • Healing Orbs – Keep yourself healthy!
    • Terrain Orbs – Creating more islands!
  • Treasure Orb tool tips to display which item they contain.
  • More Transmuter’s Kit alternate effects.
  •  Modifiers!
    • Non-numeric Modifiers are a consideration, gaining new weapons, movement patterns, attacks, etc.

 

Thank you for reading and playing!

Ataraxy – March 28th Build

March 28st Build V2.5

[Chrome Users: Webplayer support was recently removed from this browser. Due to this being an outdated build, I will focus on getting the up-to-date build working first.]

[unity src=”858″]

Use the full screen button ^

Submit Feedback
[contact-form-7 id=”789″ title=”Ataraxy Feedback!”]

 

A week of spring break let me get the main component of the Peril System working.

Check out last week’s post for bigger patch notes.

I’m eager to see how play-testing the new feature goes.

 

The Modifier UI is alongside the other enemy information.

The Modifier UI is alongside the other enemy information.

The Peril System

Enemies now gain modifiers which adjust their stats & combat prowess.

Overcoming with tough modifiers can create greater challenges.

When an enemy is slain, it grants a random modifier it has to other nearby enemies.

Modifiers are positive or negative in nature. An attentive player can dispatch enemies with negative modifiers to soften enemies up.

Gameplay Pacing

Pacing grows more important as the various systems come together. I’ve adjusted various values before doing full on balancing as many aspects are still in development.

  • Increased experience needed per player levelup
  • Reduced Loot Orb experience value
  • Enemies keep pace with the level of the player (for overall world toughening)
  • Reduced experience from Loot Orb

NEW ITEMS

Transmuter’s Kit – Primary activation transmutes internal bleeding into NOT internal bleeding.
As for the alternate activation, I don’t even know for certain. At very least, it will cost plenty of ammo and have a long cooldown.

Upcoming Development

  • Graybox Tutorial
  • Loot Orbs will be broken up into various items
    • Treasure Orbs – Gain a new item!
    • Healing Orbs – Keep yourself healthy!
    • Terrain Orbs – Creating more islands!
  • Treasure Orb tool tips to display which item they contain.
  • More Transmuter’s Kit alternate effects.
  • Modifiers!
    • Non-numeric Modifiers are a consideration, gaining new weapons, movement patterns, attacks, etc.

 

Thank you for reading and playing!

Ataraxy – March 21st Build

March 21st Build V2.3

[Chrome Users: Webplayer support was recently removed from this browser. Due to this being an outdated build, I will focus on getting the up-to-date build working first.]

[unity src=”838″]

Use the full screen button ^

Submit Feedback
[contact-form-7 id=”789″ title=”Ataraxy Feedback!”]

 

Progress has been moving along swiftly as a host of new features and items are coming together.

After a two week sprint, here are some details to report!

The revised player UI

The revised player UI

Improved UI

Throughout earlier play-tests I noticed several trends of player behavior related to the UI.

  • Failure to notice item inventory & item durability (previously in the bottom left)
  • Failure to notice enemy health & experience (previously in the top right)
  • Failure to notice own health & experience (previously top left)

So pretty much everything but the crosshair wasn’t working. This had to be fixed. The new version of the UI features a cursor-centric layout for own health & target information. The item bar was also centered. The individual items have been accented with colors to further convey the idea of item durability. The player’s XP bar was moved to the bottom of the screen in line with common conventions in MMOs.

As a final touch, the XP & HP bars for the player and enemies are now animated so they adjust over time.

 

New Items

Hemotick – This deadly insect spews a short ranged bloody haze. Feed it some of your blood and it will grow in power. Be careful or it just might kill you.

Glacial Sling – An enchanted sling for quickly launching icy arcing disks. A simple keyword explosively shatters the airborne disks.

Warp Staff – Teleport yourself with an explosive arrival. Teleport your enemies to separate them from the pack. Enemies that can’t be teleported are spatially torn, suffering substantial damage.

 

The Towermaster: "Get over here!"

The Towermaster: “Get over here!”

New enemies

Towermaster – An observant eye with an extending clutch. Keep moving or it pull you away from whatever you were doing. A disruptive enemy that thankfully can’t deal large amounts of damage.

Nullgard – A ground navigating soldier of the Blightmind. It safely advances behind a projectile-negating tower shield. It’s sole weakness is when it raises it’s shield to strike with it’s longsword.

 

Meet the Team

Alex Lobl will be joining the project as an Audio Engineer. He aims to bring life to Ataraxy’s weapons, enemies and events.

Henrique Chaltein will be assisting as a Gameplay Programmer. He assisted with the initial concept for the Grappling Hook & the Towermaster. He designed and implemented the Warp Staff.

 

Wasp visual revisited. Left facing bees coming soon!

Wasp visual revisited. Left facing bees coming soon!

GeneraL Polish

  • Health and experience bars are now animated to improve clarity.
  • Increased the strength of the Gravity Staff & Bounding Staff to make them more viable navigation options.
  • Adjusted weapon damage values.
  • Ire Wasps have a better visual effect to convey that they are an enemy.
  • Player can no longer grapple to melee projectiles. While fun it made no logistical sense. Don’t worry, this mechanic will return later!
  • Loot tokens have received a visual overhaul to better convey them as a reward.
  • Rocket flames have been visually improved.
  • Enemy death transfer particle has been visually improved.
  • GrimKeep body texture has been changed to allow players to distinguish between the different platforms.
  • New Grappling Tower terrain feature.
  • New rocks and hedges.
  • Ground navigating entities have improved pathfinding. Not perfect, but improved.
  • Web version scene bug fixes – mouse unlocking, pausing, etc.

Upcoming Development

  • Game Audio!
  • Enemy buffs as part of the Peril System.
  • More edge case improvements to enemy pathfinding.
  • Implementing the first boss
  • Game story overview – What is the player? What is the Blightmind?
  • The Transmuter’s Kit – Mainly usable to transmute internal bleeding into NOT internal bleeding. Secondary effect is a wild card, could be helpful, could make everything worse.
  • More weapons – A spear? A whip? A short sword? Unidentified potions? Provide feedback to help me decide!

Play-testing Tidbits

As a final section, I’ll note some of the things players enjoy or were surprised by.

  • Using the Grappling hook to grab a Beholder out of the sky.
  • Rocket Jumping!
  • Grappling Hooking a Top hat.
  • How new clusters arrive on scene.
  • Grappling Hook can grab tokens.
  • “BEES, LEAVE ME ALONE!”
  • Towermasters are jerks!
  • Super speed using the Bounding Staff.
  • Moon jumps with the Gravity Staff.
  • Tophats having odd pathing moments.
  • Flinging yourself with the Grappling Hook.
  • “Dude, the Towermaster grabbed my token!”
  • Using multiple mobility items together for high mobility.

 

Thank you for reading and playing!

Pacing in Ataraxy – The Peril System

The Peril System

Within Ataraxy, a world of floating islands, hostile forces and an adventuring player await. The player crosses the procedurally generated terrain facing enemies who gain dangerous Enhancements with the unnatural ability to grant their enhancements to their allies.

These enhancements are new capabilities, additional power, durability or even new tactic. The player is armed with the degrading weapons they claim from the spoils of their defeated foes.

How?

Enemies track how perilous they are. They have a Peril Level which represents how many times they have gained an Enhancement.

The Peril System is the opposite of a player leveling system.

In a player leveling system, the player progresses over a large length of time. They earn rewards for individual achievements and slowly gain new capabilities, power and options for strategic play.

In the Peril System, the enemy progresses over a short duration of time while earning Enhancements for commonly occurring events.

While the player can increase in level over the course of the game, enemies generally have less longevity. To make the Peril System matter, enemies must gain peril at an accelerated rate compared to player experience gain. Ideally, enemies should become more perilous, gaining Enhancements multiple times per encounter.

Things a player typically gains experience for

  • Completing quests
  • Slaying enemies
  • Finding items
  • Talking with NPCs

Things an enemy typically gains peril from

  • Being within a certain distance of the player
  • Damaging the player
  • Being damaged by the player
  • Healing allies
  • When the player runs away

Why?

The concept of pacing exists within all variety of media; movies, books, television, and games. Pacing is the slowly increasing tension within the unfolding dramatic actions. As a story is told, the stakes get higher and the individual actions grow in scale and importance. Pacing is critical to games. Many games are designed entirely around pacing – bosses are given multiple phases, regions are unlocked, spells become more powerful.

The goal of the Peril System is twofold.

  1. To create pacing by turning up the challenge over the duration of an encounter.
  2. To create game-play variety through different enhancement enemy combinations.

The goal is that players will find themselves in novel situations that are difficult to overcome.

Inspirations

World of Warcraft Council Encounters

You seek the secrets of Ulduar? Then take them!
World of Warcraft is the pinnacle of encounter design right alongside the Legend of Zelda. Many encounters share similar mechanics while having different interpretation or side mechanics. One of my favorite style of encounters is the Council Encounter. Typically they involve several bosses each with unique abilities that must be dealt with.

The design reference here is to a specific type of Council encounter. The specific side mechanic is when one of the bosses dies, they grant an ability or abilities to the remaining bosses. This serves to forward the pacing and growing challenge of the encounter as well as compensates for the now reduced difficulty rating with one boss felled.

My goal is to implement this style of mechanic within the general enemies in procedurally generated encounters. When the player approaches a group of enemies, the first few enemies they dispatch may be easy. However, the surviving enemies will grow more perilous after being ignored and watching their companions fall. These enemies will provide a greater challenge than the initial opponents resulting in a growing sense of challenge and suitable pacing.

Additionally, the peril system gives the player valuable decision making when the player can see how enemies will grow more powerful. For instance, if a player can see the benefits an enemy will grant to it allies they may prioritize their targets differently. Finally, with a variety of Peril Enhancements a great amount of challenge and replay-ability can naturally occur in Ataraxy.

Examples of this variant of Wow Council Encounter:

Paragons of the Klaxxi

You face the Paragons!
Paragons of the Klaxxi is one of the most complicated encounters in World of Warcraft from a player’s perspective as well as a design standpoint. I’ll run through some of the core factors.

  • There are nine paragon bosses. You have to kill all of them.
  • You fight three paragons at a time.
  • When one dies, the other two heal to full and another joins the fight.
  • The one that joins the fight is random.
  • Each paragon has different abilities. Some are more dangerous than others.
  • When you kill a paragon, the other two active paragons gain damage bonuses.
  • Each dead paragon can be utilized to give a single raid member a buff.
  • Certain paragon combinations have interactions with the ability they grant or abilities they have.

The fight is loved or hated by players for its incredible complexity and demand to play re-actively as opposed to memorizing a strict strategy.

There is no strict way to play this encounter given the random order element. From one engagement to the next, your raid’s strategy has to change. There are also decision making challenges about which paragon to kill at any given time (since you can’t kill two simultaneously). If you ignore a low priority paragon for too long they could become too much to handle and dismantle your raid.

Klaxxi Paragons teach a valuable design lesson about requiring mental consideration of the mechanics at play. My Peril System intends to make use of this on a much smaller scale with enemies that grant benefits to one another passively and on death. This combined with the varied natures of the enemies means that the player makes a meaningful decision when determining which enemy to kill.

Shadows of Mordor – The Nemesis system

Your Nemesis Awaits...
Shadows of Mordor was an unexpected surprise. It held a novel approach to hostile forces in a way that inspires player engagement and results in unique player stories.

The system functioned where under certain circumstances enemy Uruk’s could gain power, notoriety and the right to be tracked in a regional power chart. These enemies would gain or lose power depending on their interaction with the player and the player’s interaction with them.

Some examples for the player interacts with the Nemesis system

  • An Uruk fills in a power a power vacuum left by a killed nemesis
  • An Uruk that kills the player becomes more powerful.
  • Nemesis’s have strengths, weaknesses, and immunities the player can learn of.
  • A nemesis that survives an encounter can grow more powerful
  • The player can put a nemesis in a challenging situation which might weaken or strengthen them.

The Nemesis system does a fantastic job at creating longevity and player stories. The contrast my Peril system has with it is that the Nemesis is a long term system, where the benefits, interactions and challenges occur over long durations of play. My Peril system focuses on the empowerment of enemies within a single combat encounter, and the decisions the player makes when confronted with growing challenges.

In short, my idea is to apply the Nemesis system on a smaller scale to individual enemies within an encounter.

Final Words

There is no single game I have come across that approaches the idea of enemy empowerment over the course of an encounter in a non-scripted manner. In World of Warcraft’s there are many small mechanics such as enrage, or fleeing, but nothing with this degree of meat and focus.

This game began as a side project but I feel this system design is worth testing, so I will be working heavily on Ataraxy to bring the Peril System to life. I will be updating this post as my idea reaches further implementation.

The current version is still in testing for transferring Enhancements.

 

Thank you for reading,

-Jonathan Palmer

Random Platform Generation

This is the second post in a series about Ataraxy, a roguelike platform brawler. Here I will discuss some of the approach towards my Random floating island generation.

 

I started with the idea of island prefabs. I want to have variety in my islands later, so I wrote to randomly select an island prefab and then place, scale, tilt, and texture it. This was a sustainable long term approach.

Clusters – The world is made up of clusters which are located near each other. Each cluster is made up of N islands. Upon creation, a cluster instantiates islands in random orientations and positions into the world.

Other Notes

Cluster Attributes
The yellow, dark yellow and red lines are debug tools I use to evaluate parts of the cluster generation.

The yellow, dark yellow and red lines are debug tools I use to evaluate parts of the cluster generation.

As many of the characteristics of islands vary, a cluster’s parameters control the islands it creates. I found it beneficial to disable certain island initialization steps – texturing, scaling or rotation as it allowed individual clusters to feel distinct from one another. This is my first approach towards the idea of Biomes.

Later parameters such as island tilt ranges, island scale ranges and island perceived size for the Poisson Disk Sampling (smaller size means many islands overlapping one another) allow for greater variation between clusters.

This particular image showcases three different ranges in island generation. The top cluster has no random texturing or coloring, so the islands all maintain a bland template appearance. The other two islands are varied and colorful. Additionally, the top cluster islands are larger, less populated and further apart compared to the bottom two. (Last note: This image was added later after I got into the enemy path-finding components of terrain generation)

Upward ORientation

This is a pair of tips for randomly scaling and rotating the islands. In early runs, some of the scale ranges resulted in islands that appeared sideways in one dimension. This occurred when an islands X or Z scale was smaller than that island’s Y scale. While this isn’t a terrible flaw, I found it beneficial to always make the Y scale the smallest of the three, if X or Z was smaller, I simply swizzled the scales (totally an excuse to use the word swizzle).

The second tip was with the ranges of rotation I allowed. I didn’t want extreme tilting of the islands to where the CharacterController slid off of them, so I randomized the rotation between a min and maximum tilt (generally the same value). This parameter varies between clusters, so some clusters will be more tumultuous than others. As for the Y rotation, I allowed that to vary between 0 and 360, being as it didn’t matter which direction the island was facing.

March Edit: I have since disabled the random rotation of islands as it disrupts the way I can generate path nodes. I plan to re-enable random island tilting after I revise my approach to generating path nodes in a way that is not disrupted by Unity’s lackluster parent-child rotation.

Terrain Features

The environment needed to be adorned with various features to be more immersive and generate player interest. When encounter environments in nature, a meadow has an occasional tree or large rock. I wanted to place ruins, altars and checkpoints that would improve the environment as well as serve game-play purposes.

My initial approach was to give each island a small chance to spawn with a terrain feature from a group of features (checkpoints, altars with tokens, cosmetic details, etc.)

All of the objects on the platforms themselves are generated in the style of terrain features.

All of the objects on the platforms themselves are generated in the style of terrain features.

Some of the terrain features in this image: Early Wanderer (the white beaked, yellow pills with a black outline), token altar (bottom right with the yellow token), ruin (on the island north of the token), a light pillar (on the far back left light brown island).

Each terrain feature is placed on top of the island within the bounds of its edges. I evaluate the size of the terrain feature so that it wouldn’t hang off the edge of an island.

A downside came with terrain features, due to the way rotations are calculated in Unity between parent and child objects, it would skew my ability to place the features atop the island. For the time being I disabled the random rotation and will revisit it later.

While the current terrain features do not greatly improve the environment, they are a step in the right direction.

When I revisit and improve them, I seek to have different terrain features for different type of clusters and islands, creating the beginning of environmental biomes.

Melee Projectiles – the Solution to Hitscan

This is the first post in a series about Ataraxy, a roguelike platform brawler.

This content is the inspiration for creation of this series, so I will give some background on the project.

I had free time over Winter break between Graduate Semesters, so I decided to throw myself at a side project – a roguelike platform brawler.

The game world is made up of procedurally generated floating islands. You encounter enemies, gaining weapons and tools. You fight enemies that level up as you fight them, which creates natural pacing (Which I’ll no doubt discuss in a future post). Weapons fall into two general categories – ranged weapons and melee weapons. This is an in-depth description.

Common Approach to Melee weapons

A number of games (Team Fortress 2, Half Life) approach melee weapons by using hitscan – performing a single raycast or collision line forward. If this raycast hits an enemy, it deals damage or applies some other effect. This is usually the way games calculate instant velocity bullets. The difference between instant velocity bullet weapons and melee hitscan weapons is the latter usually has a short max distance before it stops checking.

This is not an ideal approach for a number of reasons. Consider a virtual axe, which has a shaft and a blade. If you were to swing the axe in TF2, you only have a boolean outcome for hitting or missing. This doesn’t allow you to consider if the player hit with the axe, the shaft or missed entirely.

I wanted a better approach than this.

I took a page out of Realm of the Mad God’s book. In that game, all of the enemies fire swaths of projectiles. Their implementation for melee weapons was a short-ranged projectile like a sword, dagger or club.

[embedyt]https://www.youtube.com/watch?v=9eIv1lk5Yzk[/embedyt]

Note the short range of this player’s attacks.

I mirrored this approach and I created a short-lived melee projectile, which I’ll call a slash.

I knew a slash would need a few points to render with. I have ‘firing points’ from around the player for different weapon starting positions – rocket launcher goes on the shoulder, machine gun goes at the waist, sword slashes are sideways, etc.

An in-game view of a sword slash. Simple but attractive when combined with a fade-out effect.

An in-game view of a sword slash. Simple but attractive when combined with a fade-out effect.

I created a box collider trigger volume (a standard way of handling  projectiles in Unity). I gave it a non-gravity affected rigidbody and a decent amount of drag so it wouldn’t travel very far.

Orienting the Collider

I oriented the box collider with the slash’s end points by using the two end points and the forward direction of the slash to find the up vector.

Within my Weapon base class, I have a method for setting up a melee projectile. It currently looks like this:

CODE: Setup Melee Projectile Parameters


This is set up so child weapons could replace this method if necessary. However, I made it generic enough that I haven’t had to replace it after implementing 4 different melee weapons. In order to use a weapon, you need to call the child’s UseWeapon function. This takes in target and fire point information. Each individual weapon’s version of UseWeapon handles differently and will until I can generalize further. Inside of the melee weapons, they configure the linePoints, lineWidth and specialVelocity if necessary while passing along certain information like the direction the projectile will move in.

A view of the editor showing a capture blade slash. Note how the slash is tilted slightly, this is based upon the two end points.

A view of the editor showing a capture blade slash. Note how the slash is tilted slightly, this is based upon the two end points.

In order to orient the Collider upwards, first we take the cross product of the two ends of our weapon strike. This gives us the direction of what is perpendicular to our line.

We then use Unity’s transform.LookAt() method to rotate the collider to orient it in the direction we’re firing. We use the the perpendicular direction to state what the projectile should consider to be ‘Up’. This results in tilting the collider to match the tilt of the two end points.

There is a final call to a method for Adjusting the projectile’s collider position. This usually means slightly moving the collider forward or backward to match the particular weapon’s visual component.

What is even better about the use of a special method for orienting the collider is that it could be overloaded in subclass weapons without changing SetMeleeProjectile.

CODE: Excerpt from Weapon.cs


Lastly, I set the alpha on the slash’s line renderer to fade over time (which aligns with the destruction of the melee projectile)

Closing Words

Alternatives

There are a great number of ways to solve this issue.

A common enough approach is the idea of a continuous hitscan, performing multiple hitscan checks to determine how long the target is hit and in what regions.

Multiple mini-projectiles can be used to see if an enemy is hit by different phases of a sword swing.

A rotational multi-projectile could model the different ways an enemy could be hit by a swinging blade (with a lower damage handle and a grazing tip)

These different approaches are usually fairly expensive and require deeper implementations.

Pros and Cons

The result of my current solution is a single projectile instantiation, box collider trigger, tag checks, a bit of vector math for rotation and finally rigidbody calculations. This approach can even be improved to suit multiple projectile creation in a particular formation as well as shape changing projectiles.

 

Thank you for reading, happy implementing!