// 2D Collision functions

package coll

import (

"github.com/setanarut/v"

)

const (

Epsilon float64 = 1e-8

Padding float64 = 0.005

)

// Hit holds the information about a collision or contact event.

type Hit struct {

// The normal vector of the hit.

Normal v.Vec

// 1. The time (0.0 to 1.0) along the movement path for moving objects.

//

// 2. Penetration depth for overlap tests

Data float64

}

// Resets the zero values.

func (h *Hit) Reset() {

*h = Hit{} // Reinitializes all fields of the struct to their zero values (nil, 0, false, etc.).

}

// SegmentNormal returns surface normal of the segment.

func SegmentNormal(pointA, pointB v.Vec) (normal v.Vec) {

d := pointB.Sub(pointA)

if d.IsZero() {

return

}

return v.Vec{X: d.Y, Y: -d.X}.Unit()

}