physics

package
v0.2.0 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Mar 10, 2023 License: BSD-2-Clause Imports: 15 Imported by: 1

Documentation

Overview

Package collision implements collision related algorithms and data structures.

Package physics implements a basic physics engine. WARNING: This package is experimental and incomplete!

Index

Constants

View Source 
const (
	BeginContactEvent = "physics.BeginContactEvent"
	EndContactEvent   = "physics.EndContactEvent"
	CollisionEv       = "physics.Collision"
)

Variables

This section is empty.

Functions

func ShowContact 

func ShowContact(scene *core.Node, contact *collision.Contact)

func ShowPenAxis 

func ShowPenAxis(scene *core.Node, axis *math32.Vector3)

func ShowWorldFace 

func ShowWorldFace(scene *core.Node, face []math32.Vector3, color *math32.Color)

Types

type AttractorForceField 

type AttractorForceField struct {
	// contains filtered or unexported fields
}

AttractorForceField is a force field where all forces point to a single point. The force strength changes with the inverse distance squared. This can be used to model planetary attractions.

func NewAttractorForceField 

func NewAttractorForceField(position *math32.Vector3, mass float32) *AttractorForceField

NewAttractorForceField creates and returns a pointer to a new AttractorForceField.

func (*AttractorForceField) ForceAt 

func (pa *AttractorForceField) ForceAt(pos *math32.Vector3) math32.Vector3

ForceAt satisfies the ForceField interface and returns the force at the specified position.

func (*AttractorForceField) Mass 

func (pa *AttractorForceField) Mass() float32

Mass returns the mass of the AttractorForceField.

func (*AttractorForceField) Position 

func (pa *AttractorForceField) Position() *math32.Vector3

Position returns the position of the AttractorForceField.

func (*AttractorForceField) SetMass 

func (pa *AttractorForceField) SetMass(newMass float32)

SetMass sets the mass of the AttractorForceField.

func (*AttractorForceField) SetPosition 

func (pa *AttractorForceField) SetPosition(newPosition *math32.Vector3)

SetPosition sets the position of the AttractorForceField.

type Broadphase 

type Broadphase struct{}

Broadphase is the base class for broadphase implementations.

func NewBroadphase 

func NewBroadphase() *Broadphase

NewBroadphase creates and returns a pointer to a new Broadphase.

func (*Broadphase) FindCollisionPairs 

func (b *Broadphase) FindCollisionPairs(objects []*object.Body) []CollisionPair

FindCollisionPairs (naive implementation)

func (*Broadphase) NeedTest 

func (b *Broadphase) NeedTest(bodyA, bodyB *object.Body) bool

type CollideEvent 

type CollideEvent struct {
	// contains filtered or unexported fields
}

type CollisionPair 

type CollisionPair struct {
	BodyA *object.Body
	BodyB *object.Body
}

CollisionPair is a pair of bodies that may be colliding.

type ConstantForceField 

type ConstantForceField struct {
	// contains filtered or unexported fields
}

ConstantForceField is a constant force field. It can be used to simulate surface gravity.

func NewConstantForceField 

func NewConstantForceField(force *math32.Vector3) *ConstantForceField

NewConstantForceField creates and returns a pointer to a new ConstantForceField.

func (*ConstantForceField) Force 

func (g *ConstantForceField) Force() *math32.Vector3

Force returns the force of the force field.

func (*ConstantForceField) ForceAt 

func (g *ConstantForceField) ForceAt(pos *math32.Vector3) math32.Vector3

ForceAt satisfies the ForceField interface and returns the force at the specified position.

func (*ConstantForceField) SetForce 

func (g *ConstantForceField) SetForce(newDirection *math32.Vector3)

SetForce sets the force of the force field.

type ContactEvent 

type ContactEvent struct {
	// contains filtered or unexported fields
}

TODO AddBodyEvent, RemoveBodyEvent

type ContactMaterial 

type ContactMaterial struct {
	// contains filtered or unexported fields
}

func NewContactMaterial 

func NewContactMaterial() *ContactMaterial

type DebugHelper 

type DebugHelper struct {
}

This file contains helpful infrastructure for debugging physics

type ForceField 

type ForceField interface {
	ForceAt(pos *math32.Vector3) math32.Vector3
}

ForceField represents a force field. A force is defined for every point.

type Material 

type Material struct {
	// contains filtered or unexported fields
}

type Narrowphase 

type Narrowphase struct {
	// contains filtered or unexported fields
}

Narrowphase

func NewNarrowphase 

func NewNarrowphase(simulation *Simulation) *Narrowphase

NewNarrowphase creates and returns a pointer to a new Narrowphase.

func (*Narrowphase) ConvexConvex 

func (n *Narrowphase) ConvexConvex(bodyA, bodyB *object.Body, convexA, convexB *shape.ConvexHull, posA, posB *math32.Vector3, quatA, quatB *math32.Quaternion) ([]*equation.Contact, []*equation.Friction)

ConvexConvex implements collision detection and contact resolution between two convex hulls.

func (*Narrowphase) GenerateEquations 

func (n *Narrowphase) GenerateEquations(pairs []CollisionPair) ([]*equation.Contact, []*equation.Friction)

GenerateEquations is the Narrowphase entry point.

func (*Narrowphase) PlaneConvex 

func (n *Narrowphase) PlaneConvex(bodyA, bodyB *object.Body, planeA *shape.Plane, convexB *shape.ConvexHull, posA, posB *math32.Vector3, quatA, quatB *math32.Quaternion) ([]*equation.Contact, []*equation.Friction)

TODO

func (*Narrowphase) ResolveCollision 

func (n *Narrowphase) ResolveCollision(bodyA, bodyB *object.Body) ([]*equation.Contact, []*equation.Friction)

ResolveCollision figures out which implementation of collision detection and contact resolution to use depending on the shapes involved.

func (*Narrowphase) SphereConvex 

func (n *Narrowphase) SphereConvex(bodyA, bodyB *object.Body, sphereA *shape.Sphere, convexB *shape.ConvexHull, posA, posB *math32.Vector3, quatA, quatB *math32.Quaternion) ([]*equation.Contact, []*equation.Friction)

TODO The second half of this method is untested!!!

func (*Narrowphase) SpherePlane 

func (n *Narrowphase) SpherePlane(bodyA, bodyB *object.Body, sphereA *shape.Sphere, planeB *shape.Plane, posA, posB *math32.Vector3, quatA, quatB *math32.Quaternion) ([]*equation.Contact, []*equation.Friction)

SpherePlane resolves the collision between a sphere and a plane analytically.

func (*Narrowphase) SphereSphere 

func (n *Narrowphase) SphereSphere(bodyA, bodyB *object.Body, sphereA, sphereB *shape.Sphere, posA, posB *math32.Vector3, quatA, quatB *math32.Quaternion) ([]*equation.Contact, []*equation.Friction)

SphereSphere resolves the collision between two spheres analytically.

type RepellerForceField 

type RepellerForceField struct {
	// contains filtered or unexported fields
}

RepellerForceField is a force field where all forces point away from a single point. The force strength changes with the inverse distance squared.

func NewRepellerForceField 

func NewRepellerForceField(position *math32.Vector3, mass float32) *RepellerForceField

NewRepellerForceField creates and returns a pointer to a new RepellerForceField.

func (*RepellerForceField) ForceAt 

func (pr *RepellerForceField) ForceAt(pos *math32.Vector3) math32.Vector3

ForceAt satisfies the ForceField interface and returns the force at the specified position.

func (*RepellerForceField) Mass 

func (pr *RepellerForceField) Mass() float32

Mass returns the mass of the RepellerForceField.

func (*RepellerForceField) Position 

func (pr *RepellerForceField) Position() *math32.Vector3

Position returns the position of the RepellerForceField.

func (*RepellerForceField) SetMass 

func (pr *RepellerForceField) SetMass(newMass float32)

SetMass sets the mass of the RepellerForceField.

func (*RepellerForceField) SetPosition 

func (pr *RepellerForceField) SetPosition(newPosition *math32.Vector3)

SetPosition sets the position of the RepellerForceField.

type Simulation 

type Simulation struct {
	// contains filtered or unexported fields
}

Simulation represents a physics simulation.

func NewSimulation 

func NewSimulation(scene *core.Node) *Simulation

NewSimulation creates and returns a pointer to a new physics simulation.

func (*Simulation) AddBody 

func (s *Simulation) AddBody(body *object.Body, name string)

AddBody adds a body to the simulation.

func (*Simulation) AddConstraint 

func (s *Simulation) AddConstraint(c constraint.IConstraint)

AddConstraint adds a constraint to the simulation.

func (*Simulation) AddContactMaterial 

func (s *Simulation) AddContactMaterial(cmat *ContactMaterial)

Adds a contact material to the simulation

func (*Simulation) AddForceField 

func (s *Simulation) AddForceField(ff ForceField)

AddForceField adds a force field to the simulation.

func (*Simulation) AddMaterial 

func (s *Simulation) AddMaterial(mat *Material)

func (*Simulation) ApplySolution 

func (s *Simulation) ApplySolution(sol *solver.Solution)

ApplySolution applies the specified solution to the bodies under simulation. The solution is a set of linear and angular velocity deltas for each body. This method alters the solution arrays.

func (*Simulation) Bodies 

func (s *Simulation) Bodies() []*object.Body

Bodies returns the slice of bodies under simulation. The slice may contain nil values!

func (*Simulation) ClearForces 

func (s *Simulation) ClearForces()

ClearForces sets all body forces in the world to zero.

func (*Simulation) GetContactMaterial 

func (s *Simulation) GetContactMaterial(bodyA, bodyB *object.Body) *ContactMaterial

GetContactMaterial returns the contact material between the specified bodies.

func (*Simulation) Paused 

func (s *Simulation) Paused() bool

Paused returns the paused state of the simulation.

func (*Simulation) RemoveBody 

func (s *Simulation) RemoveBody(body *object.Body) bool

RemoveBody removes the specified body from the simulation. Returns true if found, false otherwise.

func (*Simulation) RemoveConstraint 

func (s *Simulation) RemoveConstraint(c constraint.IConstraint)

func (*Simulation) RemoveForceField 

func (s *Simulation) RemoveForceField(ff ForceField) bool

RemoveForceField removes the specified force field from the simulation. Returns true if found, false otherwise.

func (*Simulation) RemoveMaterial 

func (s *Simulation) RemoveMaterial(mat *Material)

func (*Simulation) Scene 

func (s *Simulation) Scene() *core.Node

func (*Simulation) SetPaused 

func (s *Simulation) SetPaused(state bool)

SetPaused sets the paused state of the simulation.

func (*Simulation) Step 

func (s *Simulation) Step(frameDelta float32)

func (*Simulation) StepPlus 

func (s *Simulation) StepPlus(frameDelta float32, timeSinceLastCalled float32, maxSubSteps int)

Step steps the simulation. maxSubSteps should be 10 by default

Source Files

View all Source files

Directories

Path Synopsis
Package constraint implements physics constraints.
 Package constraint implements physics constraints.
Package equation implements SPOOK equations based on the 2007 PhD thesis of Claude Lacoursière titled "Ghosts and Machines: Regularized Variational Methods for Interactive Simulations of Multibodies with Dry Frictional Contacts"
 Package equation implements SPOOK equations based on the 2007 PhD thesis of Claude Lacoursière titled "Ghosts and Machines: Regularized Variational Methods for Interactive Simulations of Multibodies with Dry Frictional Contacts"
Package physics implements a basic physics engine.
 Package physics implements a basic physics engine.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.