Design Fundamentals of Stealth Gameplay in the Thief

  • Slides: 50
Download presentation
Design Fundamentals of Stealth Gameplay in the Thief series Randy Smith rsmith@ionstorm. com Design

Design Fundamentals of Stealth Gameplay in the Thief series Randy Smith rsmith@ionstorm. com Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Disclaimers • I didn’t design Thief’s gameplay » » Doug Church Marc Le. Blanc

Disclaimers • I didn’t design Thief’s gameplay » » Doug Church Marc Le. Blanc Tom Leonard Paul Neurath » » Tim Stellmach Greg Lo. Picollo Dorian Hart etc. • This is about open-ended stealth gameplay. Other games mentioned are being evaluated by this standard only. Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

What is stealth in Thief ? • Goal = move through space » Steal

What is stealth in Thief ? • Goal = move through space » Steal » Blackjack » etc. » Pick lock » Pick pocket • Failure = AI state becomes “alert” » Combat » Fleeing Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

How does the AI become alert? • The player has detectability » Visibility (light

How does the AI become alert? • The player has detectability » Visibility (light gem = feedback) » Audibility • The AI has senses » Seeing » Hearing • The overlap between player detectability and AI senses… » …is where the AI becomes alert or not » …is where stealth happens Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

What is this lecture about? • It is about stealth gameplay » » Player

What is this lecture about? • It is about stealth gameplay » » Player movement through space Player detectability AI Senses AI State • It is not about: » Goals (such as stealing) » Consequences (such as combat) Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Let’s design a stealth game! You are a thief in a medieval city. There

Let’s design a stealth game! You are a thief in a medieval city. There is a mansion in the distance, full of loot. A wall separates you from the mansion, and a guard patrols in front of the gate. A torch nearby spills light across the area. Do you: A) Wait until the guard has his back turned and run through the gate. B) Put out the torch with a water arrow. C) Sneak up on the guard through the shadows and blackjack him. Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

More stuff this lecture is about: • It is not about: » Stealth flavored

More stuff this lecture is about: • It is not about: » Stealth flavored gameplay » How gameplay is qualified (what makes stealth gameplay? ? ) » What is the definition of “open-ended” gameplay? » Discrete interaction • It is about: » Player expression » Analog interaction Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Major concepts for this lecture • Discrete Interaction Structures » Exemplified by Choose-Your-Own. Adventure

Major concepts for this lecture • Discrete Interaction Structures » Exemplified by Choose-Your-Own. Adventure books • Analog Interaction Structures » Exemplified (for the sake of this presentation) by Quake or other FPS Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Qualities of Discrete Interaction Structures • Finite, enumerable choices offered to the player. •

Qualities of Discrete Interaction Structures • Finite, enumerable choices offered to the player. • Player must choose one of the available options, not something in-between, not invent their own thing. • Designer must explicitly create all interaction for the player. • Should be called “Choose Someone Else’s Adventure” Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

What are Analog Interaction Structures? • Rough Definition: A collection of player -influenced, interacting

What are Analog Interaction Structures? • Rough Definition: A collection of player -influenced, interacting game systems • An abstract design tool for (de)constructing open-ended gameplay and analyzing relevant data • A “unified theory” of existing thought: » Simulation vs. Emulation » Player Tools » Partial Failure Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com » Feedback » etc.

What are analog interaction structures NOT ? • The only way to think about,

What are analog interaction structures NOT ? • The only way to think about, construct, or deconstruct any type of gameplay • Necessarily the most useful tool for the job • A ton of brand new thought Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

A Useful Metric • To what extent can the designer predict the player’s experiences?

A Useful Metric • To what extent can the designer predict the player’s experiences? » A lot, the player can not take any action the designer did not explicitly implement and intent Discrete Interaction » Not much, really, the player has nearinfinite ways to overcome the game’s challenges Analog Interaction Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Analog Expression: Player Movement in Quake • Data relating to player movement: » »

Analog Expression: Player Movement in Quake • Data relating to player movement: » » Player location (X, Y, Z) orientation (H, P) velocity vector acceleration vector • Player expression: » Accelerate in various directions » Look right, left, up, down, or combo » Some fancy movement (jump, duck, etc. ) Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

What makes it “analog”? • Hey, yea! There aren’t analog variables – so theoretically,

What makes it “analog”? • Hey, yea! There aren’t analog variables – so theoretically, all possible states are enumerable. • . . . but the player cannot “choose” their movement data. There is no “choice”. • Instead, the player uses movement tools to set or “express” their desired movement data. Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Player movement is relevant to Quake’s core gameplay • Player movement data is critical

Player movement is relevant to Quake’s core gameplay • Player movement data is critical to resolving combat from moment to moment: » Orientation is how you aim weapons » Movement is how you dodge, take cover, charge, etc. » These are examples of the player expressing “higher order concepts” Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

What else does Quake have? • For both Player and Enemies: » Movement »

What else does Quake have? • For both Player and Enemies: » Movement » Weapons that fire projectiles » Damage model (hit points) • Projectiles • A game world with physics simulation. » Collisions between player, terrain, projectiles. Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Components to Analog Interaction Structures • A game world that hosts interactions dictated by

Components to Analog Interaction Structures • A game world that hosts interactions dictated by simulations (in Quake, physics in the 3 D world) • Analog player expression (in Quake, player movement) • Analog/partial failure (in Quake, hit points) • Player tools to take arbitrary actions (in Quake, weapons that fire projectiles) Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Let’s talk about Thief already • Game world that hosts interactions dictated by simulations

Let’s talk about Thief already • Game world that hosts interactions dictated by simulations = 3 D world, similar to Quake » » Physics Line-of-sight (LOS) Lighting, light sources Sound propagation, noisy surfaces Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Analog Expression in Thief • Player movement » » Player location (X, Y, Z)

Analog Expression in Thief • Player movement » » Player location (X, Y, Z) orientation (H, P) velocity vector acceleration vector • Player movement expression » Accelerate in various directions » Look right, left, up, down, combo » Some fancy movement (jump, climb, etc. ) Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Higher Order Concepts in Expressing Stealth • Hide in shadows = move into a

Higher Order Concepts in Expressing Stealth • Hide in shadows = move into a dark part of the world • Move silently = avoid moving over loud surfaces, move slowly Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Quake with only 1 hit point • No partial / analog failure • A

Quake with only 1 hit point • No partial / analog failure • A lot of the data becomes much less relevant to resolving combat: » How damaging weapons are » Player’s emergent combat tactics when they are weak versus when they are healthy Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Stealth-related tools in Thief • Potions » Invisibility » Speed • Thrown tools »

Stealth-related tools in Thief • Potions » Invisibility » Speed • Thrown tools » Flashbomb • Arrows » Water arrow » Moss arrow » Noisemaker arrow Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Analog Interaction Structure chart = a data analysis tool • Useful for thinking about

Analog Interaction Structure chart = a data analysis tool • Useful for thinking about data: » What data the player has input into » How data flows from system to system and eventually leads to success or failure • Drawing the chart is as much art as science » Which data boxes? » How many arrows? » Draw the chart differently to analyze the data differently Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Feedback in Thief • AI State and AI Senses » Broadcast speech » Animations

Feedback in Thief • AI State and AI Senses » Broadcast speech » Animations » Behavior • Player Visibility / Audibility » Light gem » Listening • AI Movement » Player senses Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Level-building for Analog Interaction • Don’t create “scripts” » Don’t plan the player’s experiences

Level-building for Analog Interaction • Don’t create “scripts” » Don’t plan the player’s experiences for them. • Create “possibility spaces” » Populate the world with challenges » Populate the world with things that interact with the player’s tools, the simulations, manipulate the data flow » Avoid absolutes, embrace gradients Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com

Design new types of analog gameplay! • A game world that hosts interactions dictated

Design new types of analog gameplay! • A game world that hosts interactions dictated by simulations • Analog player expression • Analog failure • Player tools to take arbitrary actions Design Fundamentals of Stealth Gameplay in the Thief Series, rsmith@ionstorm. com