Method update

src/main/java/trace/physics/PhysicsSystem.kt:102–133

        })
    }

    fun update(delta: Float) {
        var timeStep = delta / 1000f
        if (timeStep > 0.2) {
            System.err.println(" warning: large timestep :" + timeStep)
            timeStep = 0.2f
        } else if (timeStep < 1e-8) {
            timeStep = 1 / 30f;
        }

        val velocityIterations = 6
        val positionIterations = 3

        world.step(timeStep, velocityIterations, positionIterations)

        allPhysicsLines.forEach {
            it.physicsToFLine()
        }

        contacts.retainAll {
            if (it.tick == TICK) {
                fire<List<field.linalg.Vec2>>(it.A, onContactStart, it.points)
                fire<List<field.linalg.Vec2>>(it.B, onContactStart, it.points)
            }
            if (it.terminated != -1L) {
                fire(it.A, onContactEnd)
                fire(it.B, onContactEnd)
                false
            }
            true
        }
        TICK++
    }