Physical world is our abstract playground for physical simulations.

Let be the new world!

Adds a body to the world.

worldWithFloor =
    add planeBody world

Check the Physics.Body module for possible bodies.

Set the standard gravity, e.g.:

planetEarth =
    setGravity { x = 0, y = 0, z = -9.80665 } world

Simulate the world, given the number of milliseconds since the last frame.

Call this function on a message from the onAnimationFrame subscription.

Get all bodies from the world.

Use this to convert bodies into visual representation, e.g. WebGL entities.

Find the closest intersection of a ray against all the bodies in the world.

The Raycast result includes the intersected body, intersection point and normal vector on the face, expressed within the local body coordinate system.

Keep bodies that satisfy the test.

Apply a function to every body in the world.

Configure constraints between pairs of bodies. Constraints allow to limit the freedom of movement of two bodies with relation to each other.

Check the Physics.Constraint module for possible constraints.

worldWithACar : World { part : String }
worldWithACar =
    constrain
        (\b1 b2 ->
            case ( (Body.getData b1).part, (Body.getData b2).part ) of
                ( "wheel1", "base" ) ->
                    [ hingeConstraint1 ]


                ( "wheel2", "base" ) ->
                    [ hingeConstraint2 ]


                ( "wheel3", "base" ) ->
                    [ hingeConstraint3 ]


                ( "wheel4", "base" ) ->
                    [ hingeConstraint4 ]


                _ ->
                    []
        )
        worldWithCarParts

Note that this example only works for a single car, otherwise it would connect wheels of one car with the base of another another. You might want to use constrainIf to apply constraints on a subset of bodies.

constrain =
    constrainIf (always True)

Configure constraints for a subset of bodies that satisfy the test.

For the above example we can tag each part of a car with the carId, and preselect parts of a single car with:

constrainCar carId =
    constrainIf (\body -> (Body.getData body).carId == carId)