func (me *Frustum) HasSphere(pos, center *unum.Vec3, radius, zNear, zFar float64) (fullyInside, intersect bool) {
if radius == 0 {
fullyInside, intersect = me.HasPoint(pos, center, zNear, zFar), false
return
}
var axPos, z, d float64
cp := center.Sub(pos)
if axPos = cp.Dot(&me.Axes.Z); axPos > zFar+radius || axPos < zNear-radius {
return
}
if axPos > zFar-radius || axPos < zNear+radius {
intersect = true
}
z, d = axPos*me.tanRadHalfAspect, me.sphereFactor.X*radius
if axPos = cp.Dot(&me.Axes.X); axPos > z+d || axPos < -z-d {
intersect = false
return
}
if axPos > z-d || axPos < -z+d {
intersect = true
}
z, d = z/me.aspectRatio, me.sphereFactor.Y*radius
if axPos = cp.Dot(&me.Axes.Y); axPos > z+d || axPos < -z-d {
intersect = false
return
}
if axPos > z-d || axPos < -z+d {
intersect = true
}
fullyInside = !intersect
return
}
func (me *FrustumPlane) setFrom(p1, p2, p3 *unum.Vec3) {
var v3 unum.Vec3
v3.SetFromCrossOf(p3.Sub(p2), p1.Sub(p2))
v3.Normalize()
me.SetFromVec3(&v3)
me.W = -v3.Dot(p2)
}
func (me *Frustum) HasPoint(pos, point *unum.Vec3, zNear, zFar float64) bool {
var axisPos float64
pp := point.Sub(pos)
if axisPos = pp.Dot(&me.Axes.Z); axisPos > zFar || axisPos < zNear {
return false
}
halfHeight := axisPos * me.tanRadHalf
if axisPos = pp.Dot(&me.Axes.Y); -halfHeight > axisPos || axisPos > halfHeight {
return false
}
halfWidth := halfHeight * me.aspectRatio
if axisPos = pp.Dot(&me.Axes.X); -halfWidth > axisPos || axisPos > halfWidth {
return false
}
return true
}