Game Developer
Game math and physics questions
157 questions on Game math and physics for game developers, easiest first.
Easy 51
- Is the enemy in front of the playereasy
- Faster diagonal movementeasy
- Where to apply physics forceseasy
- Collecting a coineasy
- Checking if the player is groundedeasy
- Value returned by Lerpeasy
- Length of a 2D vectoreasy
- Sine of 90 is not 1easy
- Two boxes overlappingeasy
- Local vs world positioneasy
- Bullets hitting their shootereasy
- Switching from idle to runeasy
- What a surface normal iseasy
- Kinematic rigidbodyeasy
- Do two boxes overlap?easy
- OnTriggerEnter never fireseasy
- Player walks through wallseasy
- Ghost passes through wallseasy
- Getting what a raycast hiteasy
- Direction from enemy to playereasy
- Distance between two pointseasy
- Cheaper range checkseasy
- Normalising a zero vectoreasy
- Speed after fallingeasy
- What a unit vector iseasy
- 90 degrees in radianseasy
- Angle of a direction vectoreasy
- Multiplying by the identity matrixeasy
- Directions ignore translationeasy
- How high a jump goeseasy
- Acceleration from a forceeasy
- Scaling a velocity vectoreasy
- Momentum of a moving carteasy
- Rotating a point by 90 degreeseasy
- Two circles touchingeasy
- Broad phase and narrow phaseeasy
- Why resting bodies sleepeasy
- Stopping enemies hitting each othereasy
- Box slides too easilyeasy
- Easing a fade in and outeasy
- Walk and run in betweeneasy
- Characters collapse on deatheasy
- Physics joint for a dooreasy
- Where a Bezier curve passeseasy
- Steering towards a targeteasy
- Continuous detection on everythingeasy
- Collider for a chaireasy
- Value of an ease-out curveeasy
- Footstep sounds in timeeasy
- Shortest turn between headingseasy
- Where skinning usually runseasy
Medium 61
- Is the target on the left or rightmedium
- Why quaternions for rotationmedium
- Fixed timestep with an accumulatormedium
- Camera smoothing changes with FPSmedium
- Fast projectile passes through wallsmedium
- Rotate turns the wrong waymedium
- Raycast ignores the Ground layermedium
- Feet slide during the walkmedium
- Feet floating on stairsmedium
- Spiky random terrainmedium
- Rotation reads back as 350medium
- FixedUpdate calls at 25 FPSmedium
- Fast ball passes through a thin wallmedium
- Feet slide during walkmedium
- Disabling a collision shape on hitmedium
- Ball does not bounce on the floormedium
- Attack plays again by itselfmedium
- Footstep sound in sync with the footmedium
- Smooth walk-to-runmedium
- Speed along a slopemedium
- Bouncing a ball off a wallmedium
- Sliding along a wallmedium
- Normal of a trianglemedium
- Area from a cross productmedium
- Angle from the dot productmedium
- Cheap inverse of a rotationmedium
- Lighting inverted after scalingmedium
- Quaternion for a 90 degree turnmedium
- Order of quaternion multiplicationmedium
- Rotation slowly distorts the meshmedium
- Same Euler angles, different posemedium
- Nlerp or slerpmedium
- Camera flips when looking straight downmedium
- One explicit Euler stepmedium
- Why update velocity firstmedium
- Time a grenade spends in the airmedium
- Launch angle for the longest throwmedium
- Energy at double speedmedium
- Damping that ignores frame ratemedium
- Ray hits a spheremedium
- Ray hits the ground planemedium
- How deep a ball sinksmedium
- Separating axis theoremmedium
- Shapes GJK can testmedium
- Choosing a grid cell sizemedium
- Impulse for a bouncemedium
- Heavy box on a light box jittersmedium
- Tall stacks wobble and fallmedium
- Physics objects stutter on 144 Hzmedium
- A camera path through set pointsmedium
- Midpoint of a quadratic Beziermedium
- Train speeds up on curvesmedium
- Agents overshoot the targetmedium
- Solving an arm to reach a pointmedium
- Breathing on top of any posemedium
- Shoot while runningmedium
- Characters snag on edgesmedium
- Spinning a windmill with physicsmedium
- Rules behind flocking birdsmedium
- Swing time of a hanging lampmedium
- How deep a floating crate sitsmedium
Hard 45
- Order of a TRS matrixhard
- Flickering distant surfaceshard
- Game slows to a crawl after a hitchhard
- Slerp spins the long way roundhard
- Angle between vectors is NaNhard
- Two hundred animated charactershard
- Checking collisions among 5,000 objectshard
- Bullets skip through thin enemieshard
- Clustered objects in a spatial structurehard
- Stiff springs explodehard
- Replays differ on another devicehard
- Slow motion makes physics choppyhard
- Physics player jitters on a high-refresh screenhard
- Off-screen enemy never attackshard
- Hit point in the object's own spacehard
- World matrix of a childhard
- Rotating a vector by a quaternionhard
- Critical damping for a camera springhard
- Spring bounce ratehard
- Stiff spring explodeshard
- Why Verlet for cloth and ropeshard
- Head-on hit of equal ballshard
- Two carts stick togetherhard
- Torque from a push on a doorhard
- Long rods turn slowlyhard
- Force at a point makes it spinhard
- Speed at the rim of a wheelhard
- Applying spin to an orientationhard
- Height of the next bouncehard
- What GJK tests about the originhard
- Time of impact for a moving ballhard
- Why sweep-and-prune is fasthard
- Box rocks on a flat floorhard
- What warm starting doeshard
- Objects bounce out of overlapshard
- Friction limit on a slopehard
- Rotated body spins wronglyhard
- Spinning bodies gain energyhard
- Ghost collisions from speculative CCDhard
- Hands drift after compressionhard
- Twisted wrists collapsehard
- Root motion and the physics capsulehard
- Stiffness in position-based clothhard
- How motion matching picks poseshard
- Skydiver top speedhard