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willnodewillnode
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The Physics Library 🍎
Converted to C++ (not guaranteed to work by this point, atleast it's free from compiler error and warns)
1 parent 55ce1ac commit 55f7209

33 files changed

+3446
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‎source/CMakeLists.txt

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@@ -50,6 +50,53 @@ set(forth_visualizer_srcs
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visualizer/WireVisualizer.h
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)
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set(forth_physics_broadphase_srcs
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physics/broadphase/BroadPhase.cpp
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physics/broadphase/BroadPhase.h
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physics/broadphase/DynamicTree.cpp
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physics/broadphase/DynamicTree.h
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)
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set(forth_physics_collision_srcs
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physics/collision/Algorithm.cpp
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physics/collision/Algorithm.h
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physics/collision/Box.cpp
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physics/collision/Box.h
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physics/collision/Capsule.cpp
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physics/collision/Capsule.h
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physics/collision/Collide.cpp
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physics/collision/Collide.h
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physics/collision/Convex.h
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physics/collision/Shape.cpp
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physics/collision/Shape.h
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physics/collision/Sphere.cpp
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physics/collision/Sphere.h
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)
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set(forth_physics_dynamics_srcs
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physics/dynamics/Body.cpp
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physics/dynamics/Body.h
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physics/dynamics/Contact.cpp
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physics/dynamics/Contact.h
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physics/dynamics/ContactManager.cpp
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physics/dynamics/ContactManager.h
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physics/dynamics/ContactSolver.cpp
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physics/dynamics/ContactSolver.h
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physics/dynamics/Island.cpp
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physics/dynamics/Island.h
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physics/dynamics/RaycastHit4.h
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physics/dynamics/Scene.cpp
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physics/dynamics/Scene.h
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)
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set(forth_physics_srcs
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physics/Common.cpp
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physics/Common.h
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${forth_physics_broadphase_srcs}
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${forth_physics_collision_srcs}
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${forth_physics_dynamics_srcs}
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)
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add_library(forth_static
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../include/forth.h
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forth.h
@@ -58,6 +105,7 @@ add_library(forth_static
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${forth_math_srcs}
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${forth_rendering_srcs}
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${forth_visualizer_srcs}
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${forth_physics_srcs}
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)
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set_target_properties(forth_static PROPERTIES LINKER_LANGUAGE CXX)

‎source/physics/Common.cpp

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#include "Common.h"
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#include "collision/Shape.h"
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namespace Forth
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{
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namespace Physics
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{
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Vector4 Common::GRAVITY = Vector4(0, -9.8f, 0, 0);
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Bounds4 Common::SIM_RANGE = Bounds4(Vector4(-1000), Vector4(1000));
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int Common::ITERATIONS = 15;
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bool Common::ALLOW_SLEEP = true;
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bool Common::ENABLE_FRICTION = true;
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float Common::SLEEP_LINEAR = 0.01f;
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float Common::SLEEP_ANGULAR = (2 / 180.f) * PI;
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float Common::SLEEP_TIME = 0.5f;
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float Common::BAUMGARTE = 0.2f;
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float Common::PENETRATION_SLOP = 0.02f;
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float Common::MAX_DT = 0.02f;
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float Common::DefMixRestitution(Shape* A, Shape* B)
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{
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return A->restitution > B->restitution ? A->restitution : B->restitution;
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}
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float Common::DefMixFriction(Shape* A, Shape* B)
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{
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return (A->friction + B->friction) * 0.5f;
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}
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static Common::ShapeMixCB MixRestitution = Common::DefMixRestitution;
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static Common::ShapeMixCB MixFriction = Common::DefMixFriction;
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} // namespace Physics
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} // namespace Forth

‎source/physics/Common.h

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#pragma once
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#include "../extras/Utils.h"
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#include "../math/Bounds4.h"
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#include "../math/math.h"
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#include "../math/Matrix4.h"
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#include "../math/Plane4.h"
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#include "../math/Ray4.h"
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#include "../math/Transform4.h"
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#include "../math/Vector4.h"
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#include "../math/Tensor4.h"
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#include <vector>
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#include <stack>
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#include <map>
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#include <algorithm>
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namespace Forth
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{
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namespace Physics
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{
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/// Common constant for physics simulation
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struct Common
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{
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/// <summary>
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/// Default gravity for all simulations.
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/// This parameter can be dynamically adjusted.
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/// </summary>
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static Vector4 GRAVITY;
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/// <summary>
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/// Simulation range helps to avoid wasted time computation of computing
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/// Objects that out of range (e.g. object keeps falling down).
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/// The object is deactivated once becomes so.
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/// </summary>
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static Bounds4 SIM_RANGE;
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/// <summary>
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/// Constant collision solving iteration.
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/// Higher values are more realistic, yet more expensive.
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/// Default is 15, can be put between 5 to 20
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/// </summary>
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static int ITERATIONS;
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/// <summary>
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/// Enables or disables rigid body sleeping.
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/// It's an important optimization on every physics engine.
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/// It's recommended to leave this on.
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/// </summary>
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static bool ALLOW_SLEEP;
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/// <summary>
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/// When two objects lay on each other should the simulator simulate friction?
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/// It's recommended to leave this on.
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/// </summary>
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static bool ENABLE_FRICTION;
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/// <summary>
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/// Constant maximum multi contact count. Don't change.
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/// </summary>
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const static int MULTICONTACT_COUNT = 16;
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/// <summary>
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/// Maximum allowed linear velocity that makes a rigidbody sleeps (Default is 0.01)
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/// </summary>
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static float SLEEP_LINEAR;
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/// <summary>
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/// Maximum allowed angular velocity that makes a rigidbody sleeps (Default is 2 deg)
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/// </summary>
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static float SLEEP_ANGULAR;
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/// <summary>
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/// Simulator don't make rigidbody sleeps instantly.
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/// They have a chance by given time to awake by itself. (Default is 0.5)
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/// </summary>
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static float SLEEP_TIME;
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/// <summary>
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/// How fast the collision must be resolved? (Default is 0.2)
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/// </summary>
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static float BAUMGARTE;
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/// <summary>
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/// Offset of allowed contact depth before kicked out by the solver.
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/// Allow very small number to avoid jitter. (Default is 0.05)
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/// </summary>
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static float PENETRATION_SLOP;
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/// <summary>
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/// Maximum allowed delta time. This prevents objects bypassing
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/// each other because of too large delta time. (Default is 0.02)
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/// </summary>
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static float MAX_DT;
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typedef float(*ShapeMixCB)(class Shape*, class Shape*);
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static ShapeMixCB MixRestitution;
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static ShapeMixCB MixFriction;
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/// <summary>
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/// Restitution (bounce) mixing. Default is max
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/// </summary>
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static float DefMixRestitution(class Shape* A, class Shape* B);
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/// <summary>
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/// Friction (slide) mixing. Default is average
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/// </summary>
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static float DefMixFriction(class Shape* A, class Shape* B);
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};
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} // namespace Physics
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} // namespace Forth

‎source/physics/broadphase/BroadPhase.cpp

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#include "BroadPhase.h"
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#include "../dynamics/ContactManager.h"
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namespace Forth
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{
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namespace Physics
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{
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BroadPhase::BroadPhase(ContactManager* manager)
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{
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Manager = manager;
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PairBuffer = ::std::vector<ContactPair>();
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MoveBuffer = ::std::vector<int>();
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}
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void BroadPhase::InsertShape(Shape* shape, const Bounds4 &aabb)
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{
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int id = Tree.Insert(aabb, shape);
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shape->broadPhaseIndex = id;
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BufferMove(id);
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}
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void BroadPhase::RemoveShape(Shape* shape)
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{
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Tree.Remove(shape->broadPhaseIndex);
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}
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// Generates the contact list.
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void BroadPhase::UpdatePairs()
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{
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PairBuffer.clear();
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// Query the tree with all moving boxs
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for (size_t i = 0; i < MoveBuffer.size(); ++i)
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{
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CurrentIndex = MoveBuffer[i];
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Tree.Query(this, Tree.GetFatAABB(CurrentIndex));
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}
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// Reset the move buffer
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MoveBuffer.clear();
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for (size_t i = 0; i < PairBuffer.size(); ++i)
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{
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// Add contact to manager
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ContactPair pair = PairBuffer[i];
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Manager->AddContact(Tree.GetShape(pair.A), Tree.GetShape(pair.B));
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}
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}
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void BroadPhase::Update(int id, Bounds4 aabb)
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{
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if (Tree.Update(id, aabb))
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BufferMove(id);
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}
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bool BroadPhase::TestOverlap(int A, int B)
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{
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return IsIntersecting(Tree.GetFatAABB(A), Tree.GetFatAABB(B));
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}
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void BroadPhase::BufferMove(int id)
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{
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MoveBuffer.push_back(id);
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}
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void BroadPhase::TreeCallback(int index)
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{
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// Cannot collide with self
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if (index == CurrentIndex)
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return;
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int iA = Min(index, CurrentIndex);
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int iB = Max(index, CurrentIndex);
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PairBuffer.push_back({ iA, iB });
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}
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} // namespace Physics
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} // namespace Forth

‎source/physics/broadphase/BroadPhase.h

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#pragma once
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#include "../Common.h"
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#include "DynamicTree.h"
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namespace Forth
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{
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namespace Physics
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{
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struct ContactPair
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{
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int A;
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int B;
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};
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class BroadPhase : public ITreeCallback
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{
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public:
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BroadPhase() {}
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BroadPhase(class ContactManager *manager);
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void InsertShape(Shape *shape, const Bounds4 &aabb);
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void RemoveShape(Shape *shape);
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// Generates the contact list.
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void UpdatePairs();
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void Update(int id, Bounds4 aabb);
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bool TestOverlap(int A, int B);
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class ContactManager *Manager;
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::std::vector<ContactPair> PairBuffer;
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::std::vector<int> MoveBuffer;
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DynamicTree Tree = DynamicTree();
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int CurrentIndex;
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void BufferMove(int id);
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void TreeCallback(int index);
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};
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} // namespace Physics
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} // namespace Forth

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