Questions tagged [physics-engine]
Software for simulating physics like collisions, forces, mass, joints, motion etc. Examples of physics engines are PhysX, Havok, Bullet and ODE.
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How are deltatime overshoots typically dealt with--or are they dealt with at all?
So I was implementing deltatime adjustment into a game when I thought of this problem. Consider a control case, with no adjustment for framerate:
Here, our character jumps up to a max height of 12.5 ...
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Should physics substepping include the entire update or only collision resolution + constraint resolving?
I'm working on a simple physics simulation and I want to use substeps to improve stability. I’m unsure whether I should apply substeps to the entire physics update or just to collision resolution.
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Best way to sync PhysicalObj to player headset position?
I’m in the process of designing a threejs-based webxr engine for simple VR games. Right now, I’m working on implementing physics with cannon-es, but I’m struggling to figure out how to sync the player’...
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How to conserve momentum in Unity?
I tend to use a lot of 2D physics based (rigid-body based) character movement in Unity, and despite lots of tweaking, I can never seem to use conservation of momentum.
I’d have to manually program in ...
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How to properly handle ball movement in a soccer game?
I'm building a soccer game (or trying), and currently running into a problem when trying to achieve the desired pass/shot.
For projectile motion, it's fine, but trying to predict rolling movement is ...
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Toxiclibs softbody physics issue with jittering under weight
hopefully this is alright to post here. I'm learning to code and working on a thing (actually trying to reproduce this https://www.instagram.com/juhani.halkomaki/reel/DGFpqfCNgZe/ )
I have created a ...
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The problem with the impulses in my physics engine
I have been analyzing the topic of creating a physics engine for a long time, at first I did it in a simple way, without thinking about real physics, then I began to do it on the basis of Verle ...
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Custom Physics Engine::Impulse Based Contact Resolver::Facing Object crawling issue when doing Box vs Box Collision
I am trying to implement basic stable 3d physics engine, I was able to get collision phase working with SAT but when I am applying impulses on box vs box contact points, I face a crawling issue. ...
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How to Replace Unity's Default Physics Engine (PhysX) with Mujoco?
I am working on a robotics simulation application in Unity. I want to replace the default physics engine, PhysX, with Mujoco. My goal is to enable a toggle within the Unity application to switch ...
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Momentum on a Kinematic Character Controller Does Not Work with Jolt 3D
After a long time, I’ve finally figured out how to add momentum to my Kinematic Character Controller in Godot 4.
Before: https://youtu.be/sPl-uA7OZ0Y
After: https://youtu.be/JvywZp5sQc8
In other words,...
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How do large physics based games (space engineers) deal with coordinates
I have recently been looking into physics engines and low level computing. At some point id like to make my own engine down the road.
Something I can't seem to find an aswer for is how physics based ...
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Ball not bouncing infinitely with perfect elastic collision settings
I'm trying to create a ball that exhibits perfect elastic collisions, meaning it should bounce infinitely without losing energy.
Here's what I've done so far:
Set the ball's restitution to 1
Set ...
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Applying impulses simultaneously at each contact point or sequentially?
I'm coding a 2d physics engine in python, and I'm struggling to understand the right way to implement collision resolution when there are multiple contact points.
Consider a very simple collision case ...
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Discretised Physics in Voxel Space
In most physics-based voxel games (like Teardown), there is usually an object-space voxel grid for each object, but no corresponding world-space grid. This means that a voxelized object can be ...
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Friction effect occasionally not applied
I'm developing a racket-ball behavior, the expected behavior is similar to a realistic tennis racket and ball, meaning both velocity and ang. velocity should be precisely applied when the ball "...
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Circle to Polygon & Circle to Circle Velocity Resolution
I am working a 2d physics engine.
Polygon to polygon collision and velocity resolution works without issue, but I am struggling to get working circle to circle and circle to polygon velocity working ...
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How to choose the normal for collision?
Here two objects collide and I use impulse to calculate the velocity after the collision.
But because there are two objects, there are two normals. Calculating impulse only requires one normal.
My ...
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Game Physics Engine : Euler integration : why body under gravity is not covering 9.8 meters/second?
I am working on very basic physics engine and I used euler interation which works like below,
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JBullet - Shoving around objects
Sometimes in video games the players can walk up to certain objects for example boxes and barrels and shove them around.
How can I recreate this system? What function do I have to use to apply force ...
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Is it possible to create an actual working physics-based ball bearing in Roblox engine?
Will it allow for making actual wheels, gears and roller coasters?
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Why do we need two constraints to calculate the friction impulse?
Why do we need two constraints to calculate friction force?
$$
\begin{align}
K_{fric_1} &= J_{fric_1}M^{-1}J^T_{fric_1} \\
&=(-u^T_1 -(r_1 \times u_1)^T u^T_1 )(r_2 \times u_1)^T) \\
K_{...
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How to implement soft-body blobs that don't pass through one another
I am learning about soft-body implementations in Unity recently, and I stumbled upon the game Blob Merge 3D.
It is quite an interesting implementation because the blobs do not overlap one another and ...
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Swept AABB for 3d collisions
https://www.gamedev.net/tutorials/programming/general-and-gameplay-programming/swept-aabb-collision-detection-and-response-r3084/
So I was following the tutorial above to implement swept aabb for ...
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Forced based physics engine
Most physics engines appear to use impulse based formulations.
Is it possible to use a forced based formulation instead with things like repulsive forces for contact constraints be defined by ...
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Identifying the wall of impact during BSP traversal
I'm building a 2D BSP based physics game and am having trouble implementing what might seem like an easy feature. I'm using Gamemaker as the basis for this project.
Basic Info and Point of Impact ...
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Should a free roaming camera movement be controlled by the physics engine (for smooth movement)?
I have a hobby engine (for fun and research) with a free roaming camera implementation that works by modifying the PositionComponent and ...
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Why doesn't multi-constraint work in this case?
The situation is as follows:
There are two objects and there are 3 constraints between the two objects.
$$
\dot{C}=(\vec{V}_{rel_a} - \vec{V}_{rel_b}) \cdot normalize(\vec{p_{a}} - \vec{p_{b}})
$$
&...
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How to rotate body in server-side physics without imparting angular velocity?
I'm developing a 2D cloud-based MMO using WebSocket and have struggled a lot to get proper working physics on the server side. I'm using Next.js for the client and currently Node.js for the server.
I ...
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Units in Unity?
I have read that in Unity 1 cube of size 1x1x1 and scale 1x1x1 is representing a cube in real life of 1mx1mx1m.
Now, the only setting I find, where I can input anything related to Units is gravity, ...
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Can Box2D be configured to conserve total energy of the system?
What I want
I want a physics engine that can support a few dozen balls and polygon objects interacting with each other in a closed environment. It needs to support objects rotating after collision. It ...
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How do you resolve continuous collision in a multi body system?
I've been trying to figure this out for weeks but every resource only provides answers for a single body. As far as I can tell for a single body you
Find the time of impact
Step up to that time
...
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Dynamic bodies falling onto static body tunnel through each other or fail to bounce
I have a problem with Box2D when 2 dynamic bodies fall onto a static body located below when their restitution is non-zero. They tunnel through each other instead of a rigid elastic bounce.
If I treat ...
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How to update the version of Box2D used in AndEngine?
I need help to use an updated Box2D library where the current version is > 2.3.0. I am unable to find a compatible library and do not know how to compile one for use with the Java Native Interface (...
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How to stop player when they hit an axis aligned bounding box?
I'm in the process of creating a game using electron and HTML5. It's going to be a pretty basic story-based platformer, but I'm ...
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Why is my Moon not orbiting Earth in my physics demo
I am in the midst of making a gravitational body demo for my physics engine. For the demo, I am trying to simulate both all the inner planets' (Mercury-Venus-Earth-Mars) orbits around the sun, as ...
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Is it advantageous if the conflict resolution for a 3d game is fake?
The game is you are a monster trainer in "3D" (I am going with WildPet(WP) for the game and the monsters). In battle with one other WP, you give the WildPets commands which can be tactical ...
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Why do physic engines apply force fully linear, despite adding torque
I checked how the applyForce function on rigid bodies in 3 different physic engines work (cannon.js, matter.js, PhysicsJS) and it seems that this is the common way ...
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Moving player inside of moving spaceship?
INTRO:
I am trying to achieve a spaceship that flies through space and the pilot can get out of their seat and walk around the ship and place physics objects in it while the ship is moving, rotating, ...
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Configurable Joint rotation doesn't seem to respect mass difference
The Problem
I've run into a physics issue in my Unity project, and have put together a simple example scene to illustrate it. Hopefully someone will be able to tell me if I'm doing something wrong.
In ...
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What can I set in rigid body and collidable objects to ensure that the angle after collision is larger?
I have a rigid body with sphere shape attached and a static collidable box. When sphere hits the box at an angle, for some reason, the angle that it bounces off from is really small: https://imgpile....
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In physics engines, what are the differences between moving an object with transform.translate and using RigidBody related functions like AddTorque?
I'm trying to recreate the ball maze puzzle game from Breath of the Wild with Unity. This is what I currently managed to make:
As you can see, it's not nearly as smooth and I feel like I lack the ...
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Unrealistic billiard ball movement
So, I have this problem, even when I apply a small amount of force, the balls seem to get pushed away easily. Here's how they should behave (GIF from 8 ball pool game):
And here's how I have it :
...
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character movment and physics on 2d game
I'm developing a client/server multiplayer game. in server side i need prevent players cross map objects like walls also i need prevent player go inside each others, instead want to slide them along ...
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Simulating a small world with Box2D
I would like to use Box2D to simulate a small world, with entity sizes around 1cm (0.01m), some smaller than that.
Box2D's FAQ says twice:
Your moving objects should be between 0.1 - 10 meters.
You ...
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Should delta be applied to every change per frame ? (e.g. acceleration, deceleration, jump, etc.?)
I have written a game based on another game's original physics. I have all the constants the original game used in the Sega Megadrive. For example:
...
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How could I move an object, while respecting the gravity and other related physics in Unity?
How could I move an object, while respecting the gravity and other related physics in Unity?
I tried using the following approach:
...
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In games physics engines, what is "tunneling", also known as the "bullet through paper problem"?
I have recently had an issue where sometimes a collision would not be detected. Someone told me that maybe I had an tunneling issue.
In the context of game development using physics, what is tunneling?...
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How to avoid CollisionShape2D bouncing which prevents Area2D detection?
Consider the player with a rectangular CollisionShape2D:
and a round enemy with a CollisionShape2D and a little bigger ...
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Difference between _process(delta) and _physics_process(delta)?
The documentation is pointing one main difference, this is the concept of being synced or not with the physics engine, so the delta parameter has more chance to be ...
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What is causing my wheel collider's raycast to fail?
I'm making custom car suspension(Custom wheelcollider etc), now I encountered a problem where if car gets dropped from a certain height, raycast will fail to detect collision and wheels intersect with ...
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