Hey DEV! 👋 Last week I shared an update on my open-world space sim _Sirius_ (on reddit KadmiumTech), built on my custom **Aether Framework** in Unreal Engine 5. Aether leverages UE5's Network Prediction Plugin (NPP) and Large World Coordinates (LWC) to handle deterministic 6DOF space physics. One of the trickiest mechanics in space games is **Relative Docking** —landing a small, agile fighter onto a massive, fast-moving capital carrier without physics jitter or netcode desync. Here is a deep dive into four specific physics bugs I encountered and how I solved them in C++! This is still work in progress and needs some adjustmends but the core works. ## ### 1. Jittery Rotation on Moving Carriers **The Problem:** Whenever a ship entered a relative movement zone, rotational smoothing was completely bypassed. Every micro-rotation of the carrier hit the player's ship as a harsh, frame-by-frame stutter. Additionally, the camera aim director was running post-physics, creating a phase shift between camera, mesh, and physics state. **The Solution:** I synchronized the Aim Director updates directly with netcode prediction ticks and re-enabled rotational smoothing for relative zones in `AetherMovementComponent.cpp`. Rotation offsets are now smoothly interpolated toward `Identity` using `FQuat::Slerp`. // AetherMovementComponent.cpp - FinalizeSmoothingFrame() if (Sync->bIsRelative && Sync->ZoneID > 0) { if (UAetherGravitySubsystem* Subsystem = GetGravitySubsystem()) { FTransform ParentTransform; if (Subsystem->GetZoneTransform(Sync->ZoneID, ParentTransform)) { TargetLocation = ParentTransform.TransformPosition(TargetLocation); TargetRotation = ParentTransform.TransformRotation(TargetRotation); } } // Smoothly interpolate translation and rotation offsets back to identity SmoothingTranslationOffset = FMath::VInterpTo(SmoothingTranslationOffset, FVector::ZeroVector, DeltaTime, 15.0f); SmoothingRotationOffset = FQuat::Slerp(SmoothingRotationOffset, FQuat::Identity, FMath::Clamp(DeltaTime * 15.0f, 0.0f, 1.0f)); VisualComponent->SetWorldLocationAndRotation( TargetLocation + SmoothingTranslationOffset, (SmoothingRotationOffset * TargetRotation).GetNormalized() ); return; } ### 2. Violently Oscillating / "Sticky" Landing Gear **The Problem:** Landing gear suspension forces were calculated using raw spring velocity multiplied by friction and mass—missing delta-time scaling and impulse limits. Pressing into the ground created an unscaled force that catapulted the ship into space in an violent feedback loop. **The Solution:** In `AetherLandingGearSim.cpp`, damping forces are now properly scaled by mass, frequency, and time step, with impulses clamped against maximum allowed Gs. I also isolated the "Sticky" (magnetic) landing gear behavior to apply a controlled, downward force vector. // AetherLandingGearSim.cpp - Step() const float ActiveStiffness = ScaledStiffness * ProgressiveMultiplier; const float ActiveDamping = (AxisVelocity < 0.0f) ? (ScaledDamping * 0.2f) : ScaledDamping; // Calculate spring force and clamp max impulses to prevent violent bounce-backs float SpringForce = (Compression * ActiveStiffness) - (AxisVelocity * ActiveDamping); SpringForce = FMath::Clamp(SpringForce, 0.0f, (MassPerGear * 980.0f) * Gear.MaxSuspensionGs); FVector CurrentGearForce = GearUpDir * SpringForce; // Separate magnetic ground attraction force if (Gear.GearMode == EAetherLandingGearMode::Sticky && Compression > 0.001f) { const float AdhesionForce = MassPerGear * 980.0f * 1.5f; CurrentGearForce -= GearUpDir * AdhesionForce; } ### 3. Rolling 90° Caused Unwanted Sideways Drift **The Problem:** The aerodynamic lift vector calculation contained a matrix transformation flaw that simplified to applying lift straight up against world gravity, regardless of ship orientation. Rolling 90° put the wings vertical, but lift kept pushing world-up, producing unintended lateral drift. **The Solution:** Lift must always evaluate relative to the ship’s **local Up axis** (`Sync->Rotation.GetAxisZ()`). In `AetherAeroSim.cpp`, the lift force vector is now computed directly along the local roof vector and scaled by atmospheric density. // AetherAeroSim.cpp - Step() if (EnvDensity > 0.001f) { const FQuat InvShipRot = Sync->Rotation.Inverse(); const FVector BodyVel = InvShipRot.RotateVector(Sync->LinearVelocity); const float ForwardSpeed = FMath::Max(0.0f, BodyVel.X); const float InvMaxLiftSpeed = 1.0f / FMath::Max(1.0f, Aux->MaxSpeed * Aux->OptimalLiftSpeedRatio); const float LiftAlpha = FMath::Clamp(ForwardSpeed * InvMaxLiftSpeed, 0.0f, 1.0f); // FIX: Get local ship up direction instead of world up! const FVector ShipUpDir = Sync->Rotation.GetAxisZ(); const float GravityMag = LocalGravity.IsNearlyZero() ? 980.0f : LocalGravity.Size(); // Apply aerodynamic lift aligned with local ship orientation Sync->LinearVelocity += ShipUpDir * (LiftAlpha * GravityMag * EnvDensity * DeltaSeconds); } ### 4. Loss of Inherited Speed When Exiting Moving Carriers **The Problem:** When exiting a carrier, zone transition logic calculated inherited world velocity correctly (e.g., combining 2,000 cm/s ship speed + 55,000 cm/s carrier speed). However, on the exact same frame, the velocity was clamped against the ship's standalone engine `MaxSpeed` (e.g., 5,000 cm/s), causing the ship to instantly lose over 90% of its momentum. **The Solution:** I removed the hard top-speed clamp during world-zone handshakes in `FAetherSpaceUtils::ProcessZoneHandshake`. Instead, excess momentum bleeds off dynamically over time (`Dynamic Bleed`) inside `AetherAeroSim.cpp`. // AetherAeroSim.cpp - Step() const float SpeedSq = Sync->LinearVelocity.SizeSquared(); const float MaxSpeedSq = FMath::Square(EffectiveMaxSpeed); // Exponentially bleed off excess inherited velocity instead of hard-clamping if (SpeedSq > MaxSpeedSq) { const float CurrentSpeed = FMath::Sqrt(SpeedSq); const float ExcessSpeed = CurrentSpeed - EffectiveMaxSpeed; const float DynamicBleed = Aux->DynamicBleedBase + (ExcessSpeed * Aux->DynamicBleedFactor); const float NewSpeed = EffectiveMaxSpeed + (ExcessSpeed * FMath::Exp(-DynamicBleed * DeltaSeconds)); Sync->LinearVelocity *= (NewSpeed / CurrentSpeed); } ### Key Takeaway Developing networked physics for space games requires strict separation of local and world reference frames. By dividing the simulation tick into modular sub-simulations (Kinematics -> Aerodynamics -> Landing Gear -> Collision) within UE5's Network Prediction Plugin, we can guarantee deterministic simulation across server and client views. Have you worked with relative physics frames or NPP in Unreal Engine 5? I’d love to hear your thoughts or questions in the comments below!

DFRobot annonce la disponibilité en précommande du seeMote Cap, un module de suivi spatial 6DoF pour les développeurs d’applications visionOS, au prix de 229 dollars. Les premières livraisons sont prévues fin septembre 2026. Ce dispositif se fixe sur des outils existants (tournevis, instruments médicaux, modèles pédagogiques, etc.) pour capturer leurs mouvements en temps réel, facilitant ainsi la création de prototypes d’applications spatiales sans nécessiter de contrôleur dédié. DFRobot fournit des ressources ouvertes (fichiers de référence, modèles 3D, exemples de code et SDK Swift) via son wiki pour aider les développeurs à intégrer le module, compatible avec l’API Spatial Accessory d’Apple. Les cas d’usage incluent la formation industrielle, la simulation médicale, l’éducation pratique et l’évaluation des compétences.

<div class="markdown"><p>DFRobot annonce la disponibilité en précommande du <em>seeMote Cap</em>, un module de suivi spatial 6DoF pour les développeurs d’applications visionOS, au prix de 229 dollars. Les premières livraisons sont prévues fin septembre 2026. Ce dispositif se fixe sur des outils existants (tournevis, instruments médicaux, modèles pédagogiques, etc.) pour capturer leurs mouvements en temps réel, facilitant ainsi la création de prototypes d’applications spatiales sans nécessiter de contrôleur dédié. DFRobot fournit des ressources ouvertes (fichiers de référence, modèles 3D, exemples de code et SDK Swift) via son wiki pour aider les développeurs à intégrer le module, compatible avec l’API <em>Spatial Accessory</em> d’Apple. Les cas d’usage incluent la formation industrielle, la simulation médicale, l’éducation pratique et l’évaluation des compétences.</p></div> <br>— <a href="https://www.augmented-reality.fr/laveille/shaare/P-vvWg" title="Permalink">Permalink</a>

Blackstar Ranger is a high-octane and immersive first-person space shooter. From the seat of your advanced fighter, you will complete contracts for BLACKSTAR, the most esteemed Private Military Faction in the solar system. With 6DOF capability, you will battle threats throughout the system.

Jouer à Titanfall 2 en Réalité Virtuelle, c'est enfin possible ! On teste ensemble la toute première version alpha du mod VR pour le chef-d'œuvre de Respawn Entertainment. Glissades, wall-run, combats nerveux et surtout… prise de contrôle d'un Titan en 6DOF. Même s'il s'agit encore d'une version tr

Step-by-step breakdown of a PS5 DualSense-controlled 6DOF robotic arm project using Raspberry Pi 5 for Bluetooth input processing and Arduino Nano for servo con

South Korean startup Soulart has launched the Soulart Station, a markerless full-body motion tracker for VR, VTubing, and motion capture. The device uses a Time-of-Flight (ToF) sensor and an onboard Neural Processing Unit (NPU) to capture 3D point cloud data and process motion tracking on the device. By running machine learning models locally, it avoids expensive PC-side GPU computation or cloud processing, delivering 23-joint 6DoF motion data with a claimed ML latency under 10 milliseconds. Soulart Station specifications: SoC – TBD; They only mention Onboard dual-core NPU and built-in graphics processor Fully on-device processing (no PC GPU or cloud required; only motion data is transmitted for privacy) Connectivity – Wi-Fi Sensors Custom Time-of-Flight (ToF) module (940 nm IR) 4K RGB + NIR cameras Tracking Method – Markerless 3D scan + on-device ML pose (no wearables, suits, or pucks required) Point cloud – ~300,000 points (millimeter-scale) with sub-1% error Scan Rate [...] The post Soulart Station – A markerless full-body motion tracker for VR and VTubers (Crowdfunding) appeared first on CNX Software - Embedded Systems News.

The soundtrack for Overload, the ultimate 6DOF action game.

174.99 €

Snap's CEO demoed the soon-to-launch Specs standalone true AR glasses live on stage, including an official Harry Potter experience from HBO.