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Advanced video game physics techniques have evolved from simple gravity simulations to complex, real-time calculations that emulate the physical world, enhancing immersion and enabling emergent gameplay. These techniques often blend theoretical physics with optimized, approximate algorithms (e.g., using Verlet integration) to maintain high frame rates while delivering realistic interactions.

Here are the key advanced video games physics techniques currently in use:

1. Advanced Collision Detection and Resolution

• Continuous Collision Detection (CCD): Unlike traditional discrete methods that may miss fast-moving objects, CCD calculates potential collisions over time, ensuring high-speed projectiles or fast-moving objects do not pass through walls, a crucial feature for shooters.
• Broad-Phase and Narrow-Phase Optimization: To handle large environments, engines use broad-phase techniques (e.g., Spatial Partitioning, Bounding Volume Hierarchies) to quickly filter out objects that are far apart, followed by narrow-phase, detailed checks only for close objects.
• Separating Axis Theorem (SAT): A mathematical approach to check for collisions between convex shapes, determining if they overlap by checking for a separating axis. 

2. Simulation Types and Techniques

• Finite Element Method (FEM): Used for highly accurate simulation of deformable objects, breaking them into small pieces to calculate structural integrity, stress, and deformation under force.
• Soft-Body Dynamics: Simulates non-rigid, deformable materials like jelly, rubber, or cloth. These methods often involve particle systems, where individual sections of an object are simulated.
• Fluid Dynamics and Particle Systems: Real-time simulations of liquids, gases, smoke, and fire using particle systems. Modern techniques are moving towards high-resolution fluid simulation that allows for interactive, flowing, and splashing water.
• Constraint Solvers: Instead of just calculating forces, constraints (like hinges, ropes, or joints) are solved iteratively (e.g., using relaxation techniques like Gauss-Seidel) to keep objects attached or rigid. 

3. Procedural and Character Physics

• Ragdoll Physics: A form of procedural animation that replaces static death animations with a realistic, physics-driven simulation of a character's skeleton collapsing and reacting to the environment.
• Inverse Kinematics (IK): A procedural technique to compute the proper orientation of a character's limbs (e.g., feet placing correctly on uneven terrain) based on their interaction with the environment.
• Destruction Physics: Real-time, in-game fracturing of objects (e.g., shattering glass or breaking wooden beams) based on the force and angle of impact. 

4. Optimization and Performance

• GPU Accelerated Physics: Moving physics calculations from the CPU to the GPU (e.g., Nvidia PhysX) allows for thousands of particles or complex soft-body simulations to run in real-time without bottlenecking the main processor.
• Verlet Integration: A numerical integration method that is highly stable and used to calculate the positions of particles in a system, particularly in cloth and ragdoll simulations.
• Memory Pooling: Frequently re-using objects (like bullets or debris) to reduce the overhead of creating and destroying objects during intense action. 

5. Future Trends

• Deep Learning for Physics: Integrating AI into physics engines to predict or approximate complex simulations in real-time, resulting in more adaptive and personalized interactions.
• Quantum Physics Simulations: Early research into incorporating quantum mechanics concepts like entanglement and uncertainty for unique gameplay mechanics. 

These techniques are implemented through specialized engines like Havok, PhysX, Bullet, and native tools in Unreal Engine or Unity.