diff options
Diffstat (limited to 'hitable.go')
| -rw-r--r-- | hitable.go | 39 |
1 files changed, 20 insertions, 19 deletions
@@ -2,6 +2,7 @@ package main import "math" +// HitRecord contains data of a ray hiting a hitable type HitRecord struct { time float64 point Vec3D @@ -9,44 +10,44 @@ type HitRecord struct { material Material } +// Hitable is a physical volume a Ray can hit type Hitable interface { - Hit(ray Ray, t_min float64, t_max float64) HitRecord + Hit(ray Ray, tmin float64, tmax float64) HitRecord Normal(point Vec3D, ray Ray) Vec3D } +// HitableList ... type HitableList []Hitable -func (hitable_list HitableList) Hit(ray Ray, t_min float64, t_max float64) HitRecord { - closest_hit := HitRecord{T_MAX, Vec3D{}, Vec3D{}, nil} - for _, hitable := range hitable_list { - hit := hitable.Hit(ray, t_min, closest_hit.time) +// Hit finds the closest hit of all hitables +func (hitableList HitableList) Hit(ray Ray, tmin float64, tmax float64) HitRecord { + closestHit := HitRecord{TMax, Vec3D{}, Vec3D{}, nil} + for _, hitable := range hitableList { + hit := hitable.Hit(ray, tmin, closestHit.time) if hit.time > 0 { - closest_hit = hit + closestHit = hit } } - if closest_hit.time < T_MAX { - return closest_hit - } else { - return HitRecord{} + if closestHit.time < TMax { + return closestHit } + return HitRecord{} } +// Sphere ... type Sphere struct { center Vec3D radius float64 material Material } +// Normal ... func (sphere Sphere) Normal(point Vec3D, ray Ray) Vec3D { - out_normal := SubVec3D(point, sphere.center).Unit() - if DotProduct(ray.direction, out_normal) < 0.0 { - return out_normal - } else { - return out_normal.Invert() - } + return SubVec3D(point, sphere.center).Unit() } -func (sphere Sphere) Hit(ray Ray, t_min float64, t_max float64) HitRecord { +// Hit ... +func (sphere Sphere) Hit(ray Ray, tmin float64, tmax float64) HitRecord { oc := SubVec3D(ray.origin, sphere.center) a := DotProduct(ray.direction, ray.direction) b := 2.0 * DotProduct(oc, ray.direction) @@ -55,12 +56,12 @@ func (sphere Sphere) Hit(ray Ray, t_min float64, t_max float64) HitRecord { if discriminant > 0 { root := math.Sqrt(discriminant) time := (-b - root) / (2.0 * a) - if t_min < time && time < t_max { + if tmin < time && time < tmax { point := ray.PointAt(time) return HitRecord{time, point, sphere.Normal(point, ray), sphere.material} } time = (-b + root) / (2.0 * a) - if t_min < time && time < t_max { + if tmin < time && time < tmax { point := ray.PointAt(time) return HitRecord{time, point, sphere.Normal(point, ray), sphere.material} } |