package geo import "fmt" type Box struct { TopLeft *Point Width float64 Height float64 } func NewBox(tl *Point, width, height float64) *Box { return &Box{ TopLeft: tl, Width: width, Height: height, } } func (b *Box) Copy() *Box { if b == nil { return nil } return NewBox(b.TopLeft.Copy(), b.Width, b.Height) } func (b *Box) Center() *Point { return NewPoint(b.TopLeft.X+b.Width/2, b.TopLeft.Y+b.Height/2) } func (b *Box) Intersections(s Segment) []*Point { pts := []*Point{} tl := b.TopLeft tr := NewPoint(tl.X+b.Width, tl.Y) br := NewPoint(tr.X, tr.Y+b.Height) bl := NewPoint(tl.X, br.Y) if p := IntersectionPoint(s.Start, s.End, tl, tr); p != nil { pts = append(pts, p) } if p := IntersectionPoint(s.Start, s.End, tr, br); p != nil { pts = append(pts, p) } if p := IntersectionPoint(s.Start, s.End, br, bl); p != nil { pts = append(pts, p) } if p := IntersectionPoint(s.Start, s.End, bl, tl); p != nil { pts = append(pts, p) } return pts } func (b *Box) ToString() string { if b == nil { return "" } return fmt.Sprintf("{TopLeft: %s, Width: %.0f, Height: %.0f}", b.TopLeft.ToString(), b.Width, b.Height) }