did roblox remove physics solver

by Mack Haag IV 9 min read
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Before PGS physics, Roblox used a faster but more inaccurate solver known as spring physics, which as of March 4, 2019, has been completely removed in favor of the newer PGS physics solver. Contents 1 Released solvers 1.1 Spring physics 1.2 Projected Gauss-Seidel 1.3 Comparison of spring physics and PGS physics 2 Unreleased solvers

We are switching all Roblox games, regardless of current solver setting, to the PGS physics solver on Monday, March 4th, 2019.Feb 26, 2019

Full Answer

What is the best physics solver for Roblox?

Released solvers 1 Spring physics. Spring physics was the first physics engine to be in use by Roblox, and is used to be used in most games. 2 Projected Gauss-Seidel. Projected Gauss-Seidel physics, or PGS physics, is a more reliable but more costly physics solver released in summer of 2015. 3 Comparison of spring physics and PGS physics. ...

What physics engine does Roblox use?

Before PGS physics, ROBLOX used a faster but more inaccurate solver known as spring physics, which as of March 4, 2019, has been completely removed in favor of the newer PGS physics solver. As of September 2015, two different physics engines are available to use, spring physics and PGS physics.

Should Roblox remove PGS physics solver?

Since PGSPhysicsSolver was released, many of those Robloxians, mostly people from the car community protested Roblox that they should remove PGS so the famed SS chassis, made by SecondLogic could work properly again. The symptoms include The chassis breaks often.

How does Roblox physics work?

It takes into account how parts are connected with joints and how they collide with each other so that everything moves in a physically realistic way (as seen in this physics demonstration). The original solver in ROBLOX computes how joints and collisions work using extremely stiff spring equations.

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Does Roblox have a physics engine?

The PhysicsSettings is a singleton class, which lets developers view debugging features in Roblox's physics engine. It can be found under the Physics tab in Roblox Studio's settings menu.

Are Roblox physics good?

0:134:01The Best Roblox Physics Game - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd i'm not gonna lie it's probably one of the best best physics games i've seen in a long time theMoreAnd i'm not gonna lie it's probably one of the best best physics games i've seen in a long time the game is called destruction physics this game is by quinn quinoa yeah this person.

How does Roblox physics work?

The physics engine is responsible for determining how parts move in a ROBLOX game. It takes into account how parts are connected with joints and how they collide with each other so that everything moves in a physically realistic way (as seen in this physics demonstration).

What is a PGS solver?

What is the PGS Solver? The PGS Solver is Roblox's state of the art physics solver which offers a range of simulation capabilities not available in Roblox's legacy solver. Note, the PGS solver is currently the default physics solver used by Roblox.

How do you get physics on Roblox?

0:1311:15How to Use PhysicsService | Roblox Advanced Tutorials - YouTubeYouTubeStart of suggested clipEnd of suggested clipSo now we want to create a collision group and when a collision group is it's pretty much how youMoreSo now we want to create a collision group and when a collision group is it's pretty much how you add shoes. It's pretty much kind of like a table like you insert objects into the table.

How do you make a physics engine?

5:037:37Designing a Physics Engine in 5 minutes - YouTubeYouTubeStart of suggested clipEnd of suggested clipWe can split objects into collision object and rigid body structs we'll make a rigidbody inheritMoreWe can split objects into collision object and rigid body structs we'll make a rigidbody inherit from collision objects to reuse the collider properties and allow us to store both types easily.

How do I use Vectorforce?

1:1210:23How to use VectorForces in Roblox Studio (& Anti-Gravity Effect)YouTubeStart of suggested clipEnd of suggested clipAnd the way you create a vector force is go to model then to create. Then go to vector force so hereMoreAnd the way you create a vector force is go to model then to create. Then go to vector force so here i have this little green thing this is your attachment.

Is there a limit in Roblox Studio?

There's not really a limit to how many parts can be in a game, although of course if you add too many parts to a game, it can impact performance. Roblox BaseParts are optimized and are more efficient to use, so you can get away with using a lot of these types of parts.

What is BodyGyro Roblox?

The BodyGyro object applies a torque (rotational force) on a BasePart such that it maintains a constant angular displacement, or orientation. This allows for the creation of parts that point in a certain direction, as if a real gyroscope were acting upon it.

What are physics engine in games?

A physics engine is computer software that provides an approximate simulation of certain physical systems, such as rigid body dynamics (including collision detection), soft body dynamics, and fluid dynamics, of use in the domains of computer graphics, video games and film (CGI).

Is Dynablocks still available?

[1]. The domain dynablocks.com was registered by Jim Stevens on December 12, 2003. [2]The name was later scrapped in favor of Roblox in early 2004[3]. Until late 2020, dynablocks.com, dynablox.com, and dynablock.com were all used as redirects to roblox.com.

What was the first video game with a physics engine?

One of the earliest examples of dynamic, multidimensional physics calculations being made in a video game is, of course, Atari's Pong and its several smaller predecessors.

Who made interactive physics?

David BaszuckiInteractive Physics was a physics simulation created in 1989 by Knowledge Revolution, which was founded by David Baszucki, the same man behind Roblox.

What is the architecture of our solver?

The architecture of our solver follows the idea of Guendelman-Bridson-Fedkiw, where the velocity and position stepping are separated by the constraint resolution. Our time sequencing is:

What is Roblox engine?

The Roblox engine uses analytical methods to compute the dynamic response of constraints, as opposed to penalty methods that were used before. Analytics methods were initially introduced in Baraff 1989, where they are used to treat both equality and non-equality constraints in a consistent manner.

How to iron out high mass ratio issues in equality constraints?

Additionally, high mass ratio issues in equality constraints are ironed out by preconditioning the PGS using the sparse LDL decomposition of the constraint matrix of equality constraints. Dense submatrices of the constraint matrix are sparsified using a method we call Body Splitting. This is similar to the LDL decomposition used in Baraff 1996, but allows more general mechanical systems, and solves the system in constraint space. For more information, you can see my GDC 2020 presentation.

How are LCPs solved?

The LCPs are solved using a PGS / Impulse Solver popularized by Catto 2005 (also see Catto 2009 ). This method is iterative and considers each individual constraints in sequence and resolves it independently. Over many iterations, and in ideal conditions, the system converges to a global solution.

What is the best book for rigid body simulation?

An excellent reference for rigid body simulation is the book Erleben 2005 that was recently made freely available. You can find online lectures about physics-based animation, a blog by Nilson Souto on building a physics engine, a very good GDC presentation by Erin Catto on modern solver methods, and forums like the Bullet Physics Forum and GameDev which are excellent places to ask questions.

What is frictionless contact?

The frictionless contacts are modeled using a linear complementarity problem (LCP) as described in Baraff 1994. Friction is added as a non-linear projection onto the friction cone, interleaved with the iterations of the Projected Gauss-Seidel.

How does the Physics Engine work?

The main idea of the physics engine is to discretize the motion using time-stepping. The equations of motion of constrained and unconstrained rigid bodies are very difficult to integrate directly and accurately. The discretization subdivides the motion into small time increments, where the equations are simplified and linearized making it possible to solve them approximately. This means that during each time step the motion of the relevant parts of rigid bodies that are involved in a constraint is linearly approximated.

What is physics in Roblox?

Physics are part of the physics engine on Roblox . The original physics engine was considered a very realistic engine by the staff members, but has been questioned due to the amount of fails and inaccuracies with the engines. In 2013, there was an articulated physics engine being worked on but was stopped because of it being slow and not solving collisions, and in mid 2015, a new collisions system was released first known as experimental physics but is now known as PGS physics. Before PGS physics, Roblox used a faster but more inaccurate solver known as spring physics, which as of March 4, 2019, has been completely removed in favor of the newer PGS physics solver.

Why was the solver canceled?

However, according to Zeuxcg, the solver was canceled because it was an extremely slow solver and did not solve for collisions between moving parts.

What is articulated physics?

The articulated physics solver was being worked on in late 2013. It allowed for extremely complex joints, allowing for extremely complex machines without the person needing to do a lot of CFrame math with welds known as inverse kinematics .

When did Roblox remove spring physics?

Before PGS physics, Roblox used a faster but more inaccurate solver known as spring physics, which as of March 4, 2019 , has been completely removed in favor of the newer PGS physics solver.

What is spring physics?

Spring physics was the first physics engine to be in use by Roblox, and is used to be used in most games. It is a faster engine for physics, but has a lot more give for things like collisions, which allows parts to go a little bit inside of other parts, allowing more bend. However, the engine is a lot more unreliable when used with a lot of physics.

Why do mechanisms fail less?

Mechanisms fail less due to less give or bending.

Is spring physics out?

As of March 2019, spring physics has been phased out entirely in favor of PGS physics.

What is the physics engine in Roblox?

The physics engine is responsible for determining how parts move in a ROBLOX game. It takes into account how parts are connected with joints and how they collide with each other so that everything moves in a physically realistic way (as seen in this physics demonstration).

How does a PGS solver work?

On the other hand, the PGS solver uses a system of equations representing all the parts, joints and collisions and solves the entire set of equations together.

How much of Roblox is using the PGS solver?

Today, nearly 75% of Roblox game play time is using the new solver. With nearly full-time focus on extending and optimizing the new solver technology, now is the time to work together to get all games using the PGS solver!

Why are my wheels tilting in Roblox?

The wheels were tilting due to bending at the hinge joint, an expected artifact of the spring-based legacy solver. I noticed similar flexing, or joint sponginess, when I tried to build heavy doors, unbalanced rotors, and cars driving aggressively over obstacles. I simply could not get the precision I needed from the spring solver for the types of models I wanted to build. Experiences like this, both from within Roblox and across our entire developer community, fueled our desire to develop the next-generation solver with much better joint precision, performance, and extensibility.

What is PGS solver?

In 2015 we moved forward on new solver research and development, and later that year released the PGS solver, which employs an innovative formulation specifically designed to accurately simulate models with joints and collisions. In other words, joints no longer separate or bend during simulation, even under very high force and torque conditions.

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Implementing The Laws of Physics

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The main objective of a physics engine is to simulate the motion of bodies in a virtual environment. In our physics engine, we care about bodies that are rigid, that collide and have constraints with each other. A physics engine is organized into two phases: collision detection and solving. Collision detection finds intersection…
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Taking Small Steps

  • The main idea of the physics engine is to discretize the motion using time-stepping. The equations of motion of constrained and unconstrained rigid bodies are very difficult to integrate directly and accurately. The discretization subdivides the motion into small time increments, where the equations are simplified and linearizedmaking it possible to solve them approximately…
See more on blog.roblox.com

Solving

  • Having linearized the equations of motion for a time step, we end up needing to solve a linear system or linear complementarity problem (LCP). These systems can be arbitrarily large and can still be quite expensive to solve exactly. Again the trick is to find an approximate solution using a faster method. A modern method to approximately solve an LCP with good convergence propert…
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Mitigation Strategies

  • A solver has two major sources of inaccuracies: time-stepping and iterative solving (there is also floating point drift but it’s minor compared to the first two). These inaccuracies introduce errors in the simulation causing it to drift from the correct path. Some of this drift is tolerable like slightly different velocities or energy loss, but some are not like instabilities, large energy gains or disloc…
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Getting More Details

  • Traditionally there are two mathematical models for articulated mechanisms: there are reduced coordinate methods spearheaded by Featherstone, that parametrize the degrees of freedom at each joint, and there are full coordinate methods that use a Lagrangian formulation. We use the second formulation as it is less restrictive and requires much simpler mathematics and implem…
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in Conclusion

  • The field of game physics simulation presents many interesting problems that are both exciting and challenging. There are opportunities to learn a substantial amount of cool mathematics and physics and to use modern optimizations techniques. It’s an area of game development that tightly marries mathematics, physics and software engineering. Even if Roblox has a good rigid …
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