Game Development

You can reason about the game loop, frame timing and 2D coordinate spaces well enough to move a sprite predictably.

1. 1The game loopYou can name the three phases of a game loop and say what belongs in each.10m25xp
2. 2Delta time and frame independenceYou can scale movement by delta time so speed is identical at 30 and 144 frames per second.11m28xp
3. 3Fixed timestep versus variable timestepYou can decide which systems run on a fixed physics tick and which run per rendered frame.11m28xp
4. 4Screen space versus world spaceYou can convert a point between screen coordinates and world coordinates.10m25xp
5. 5Transforms, local space and parentingYou can predict a child object's world position from its parent's transform.11m28xp
6. 6Vector maths you actually needYou can add, scale, normalise and measure vectors to control direction and speed separately.12m30xp
7. 7Dot and cross products in 2DYou can use the dot product to test facing and the 2D cross product to test turn direction.11m28xp
8. 8Interpolation and easingYou can move a value smoothly toward a target using interpolation with frame-rate correct damping.11m28xp
9. 9Randomness and seedsYou can use a seeded random generator so a run can be reproduced for debugging.9m23xp
10. 10Debug drawing and overlaysYou can render collision shapes, velocities and state labels on top of the game to diagnose behaviour.9m23xp
11. 11Reading frame timeYou can read a frame time graph and distinguish a low average frame rate from an intermittent spike.10m25xp

You can read input from multiple devices and translate it into responsive, forgiving character control.

1. 1Polling input versus input eventsYou can choose between polling a held key and reacting to a discrete press event.10m25xp
2. 2Action maps instead of raw keysYou can route physical inputs through named actions so devices can be remapped.10m25xp
3. 3Normalising input into a directionYou can turn discrete and analog inputs into one direction vector with consistent magnitude.9m23xp
4. 4Analog sticks and deadzonesYou can apply a deadzone and response curve to a stick so idle drift disappears without losing precision.10m25xp
5. 5Input bufferingYou can buffer a pressed action for a few frames so slightly early presses still register.11m28xp
6. 6Coyote time and forgiveness windowsYou can allow a jump shortly after leaving a ledge and explain why it improves feel.10m25xp
7. 7Input latency sourcesYou can list where latency accumulates between a button press and a visible response.10m25xp
8. 8Kinematic versus dynamic bodiesYou can choose between engine-driven physics and directly scripted motion for a character.11m28xp
9. 9Acceleration, friction and top speedYou can tune acceleration, deceleration and maximum speed to hit a target control feel.12m30xp
10. 10Gravity and jump arc tuningYou can derive jump velocity from a desired height and shape the arc with asymmetric gravity.12m30xp
11. 11Assembling a character controllerYou can order grounding, input, velocity integration and collision resolution correctly within one update.12m30xp

You can detect overlaps between 2D shapes and resolve them into believable movement against level geometry.

1. 1Axis-aligned bounding box overlapYou can test two axis-aligned rectangles for overlap on both axes.10m25xp
2. 2Circle and capsule collisionYou can test circles against circles and boxes using squared distance comparisons.10m25xp
3. 3Rotated shapes and the separating axis ideaYou can explain how a separating axis proves two convex shapes do not overlap.12m30xp
4. 4Broad phase and narrow phaseYou can reduce pair checks with a spatial partition before running exact tests.11m28xp
5. 5Collision layers and masksYou can configure which categories of object can collide with which.10m25xp
6. 6Resolving penetrationYou can push overlapping bodies apart along the minimum translation vector.11m28xp
7. 7Swept collision and tunnellingYou can prevent a fast object from passing through thin geometry within one step.12m30xp
8. 8Raycasts and shapecastsYou can cast a ray to query geometry for line of sight, ground checks and hit scanning.11m28xp
9. 9Slopes and one-way platformsYou can walk a character up a slope without launching it and pass upward through one-way platforms.12m30xp
10. 10Hitboxes, hurtboxes and combat framingYou can separate the shape that deals damage from the shape that receives it and time them per animation frame.11m28xp
11. 11Tilemap collisionYou can resolve movement against a tile grid using tile lookups instead of per-tile colliders.11m28xp

You can structure game objects, their state machines and their communication so behaviour stays predictable as the game grows.

1. 1Scenes, nodes and reusable prefabsYou can package an object with its children and settings into a reusable unit and instance it.10m25xp
2. 2Composition over deep inheritanceYou can express a behaviour as an attachable component rather than a new subclass.11m28xp
3. 3Spawning, despawning and lifecycle hooksYou can initialise and tear down an entity so no dangling references remain.10m25xp
4. 4Object poolingYou can reuse instances from a pool and reset their state fully on reuse.11m28xp
5. 5Finite state machines for behaviourYou can model a character's states and transitions so only one state is active at a time.12m30xp
6. 6Hierarchical and pushdown statesYou can nest states or stack them so a temporary state can return to what came before.11m28xp
7. 7Signals, events and direct referencesYou can choose between a direct call and an event when connecting two systems.11m28xp
8. 8System update orderYou can define an explicit update order so cross-system reads see consistent data.11m28xp
9. 9Data-driven tuning valuesYou can externalise gameplay constants into data so they can be iterated without code changes.10m25xp
10. 10Saving and loading game stateYou can serialise the minimal authoritative state and restore it without duplicating entities.11m28xp
11. 11Simple enemy AI with states and steeringYou can build a patrol, detect and chase behaviour with hysteresis on detection.12m30xp

You can render sprites correctly and drive animation from gameplay state with proper layering and cameras.

1. 1Sprites, pivots and pixel alignmentYou can set a sprite's pivot so rotation and flipping happen around the intended point.10m25xp
2. 2Texture atlases and draw callsYou can pack sprites into an atlas and explain how it reduces draw calls.10m25xp
3. 3Draw order, layers and z-sortingYou can control which sprites draw on top using layers and sort keys.10m25xp
4. 4Frame-based sprite animationYou can play a frame sequence at a set rate independent of frame rate.10m25xp
5. 5Driving animation from gameplay stateYou can select an animation clip from the character's state rather than triggering clips from input.11m28xp
6. 6Animation events and frame dataYou can trigger gameplay effects on specific animation frames.10m25xp
7. 7Tweens and procedural squashYou can animate a transform property over time with a tween and chain it into a sequence.10m25xp
8. 8Particle systemsYou can configure emission rate, lifetime and velocity spread for a readable effect.10m25xp
9. 9Camera follow and dampingYou can follow the player with smoothing and a deadzone so small movements do not move the camera.11m28xp
10. 10Screen shake and impact effectsYou can add decaying screen shake as an offset that does not corrupt camera state.10m25xp
11. 11Parallax layersYou can scroll background layers at fractional camera speed to imply depth.9m23xp
12. 12Resolution, aspect ratio and pixel-perfect scalingYou can pick a scaling strategy that keeps art crisp across window sizes.10m25xp

You can layer feedback, audio and pacing so the same mechanics feel dramatically better to play.

1. 1HitstopYou can pause simulation briefly on impact to sell weight without breaking timers.10m25xp
2. 2Layering feedback channelsYou can stack visual, audio and haptic feedback on one event and check each channel's contribution.11m28xp
3. 3Readability and telegraphingYou can give a threat a distinct wind-up so a reacting player can respond fairly.11m28xp
4. 4Sound effects, buses and mixingYou can route sounds to buses and set levels so critical cues stay audible.10m25xp
5. 5Music states and transitionsYou can switch music between game states without an audible cut.10m25xp
6. 6Difficulty pacingYou can sequence encounters so each introduces one new demand before combining them.11m28xp
7. 7Teaching without textYou can design a first encounter that teaches a mechanic through safe, guided practice.10m25xp
8. 8HUD layout and anchoringYou can anchor UI elements so the layout survives different resolutions and safe areas.10m25xp
9. 9Menus, focus and pauseYou can build a menu that is fully navigable by keyboard and gamepad and pauses gameplay correctly.10m25xp
10. 10Accessibility optionsYou can add options that make the game playable without relying on one sense or reaction speed.10m25xp
11. 11Instrumenting playtestsYou can record where players die, stall and quit, then act on the resulting data.10m25xp

You can build levels and progression systems that hold the core loop together across a whole game.

1. 1Authoring levels with tilemapsYou can lay out a level on a tile grid with separate visual and collision layers.10m25xp
2. 2Design metricsYou can derive maximum jump distance and height and size level geometry against them.11m28xp
3. 3Encounter compositionYou can combine enemy types and terrain so an encounter poses one clear question.11m28xp
4. 4Checkpoints and failure costYou can place checkpoints so the retry loop stays short after a death.10m25xp
5. 5Gating and ability-based progressionYou can gate an area behind an ability so the player learns before being tested.10m25xp
6. 6Reward economiesYou can balance a currency's income against its costs so upgrades stay meaningful.11m28xp
7. 7Procedural level generationYou can generate a connected layout from rules and validate that it is completable.12m30xp
8. 8Difficulty modes and assistsYou can expose assist options that widen the audience without forking level design.10m25xp
9. 9Content pipeline and iteration speedYou can shorten the loop between changing a level and playing it.10m25xp
10. 10Reviewing the core loop end to endYou can trace one full play session and identify which system breaks the loop first.12m30xp

You can profile a build, fix the dominant cost and produce a release that runs on target hardware.

1. 1Finding whether you are CPU or GPU boundYou can determine which side of the pipeline limits frame time before optimising.11m28xp
2. 2Allocations and collection spikesYou can find per-frame allocations and remove them from hot paths.11m28xp
3. 3Overdraw and fill rateYou can identify layered transparent geometry as a fill cost and reduce it.10m25xp
4. 4Asset budgets and import settingsYou can set texture and audio import settings to meet a memory budget.10m25xp
5. 5Loading, streaming and hiding hitchesYou can load a level asynchronously so the game does not freeze during transitions.10m25xp
6. 6Determinism and replay recordingYou can record inputs and replay them to reproduce a bug exactly.11m28xp
7. 7Debug versus release buildsYou can produce a release build and explain which checks and symbols were removed.9m23xp
8. 8Targeting platform constraintsYou can adapt input, resolution and performance targets to a specific platform.10m25xp
9. 9Crash reporting and telemetryYou can capture a crash report from a player build and read the stack back to source.9m23xp
10. 10Scoping with a vertical sliceYou can define a vertical slice that proves the core loop before content production begins.10m25xp