scene

type AABB struct {
	Min, Max vecmath.Vec3dA
}

type FloatColor struct {
	R, G, B float32
}

type LightSource struct {
	Position          vecmath.Vec3d
	Diffuse, Specular FloatColor
}

type Material struct {
	Ambient      FloatColor
	Diffuse      FloatColor
	Specular     FloatColor
	Specularity  float32
	Reflectivity float32
	Transparency float32

	RefractionIndex float32
}

type Plane struct {
	TraceableBase

	DistanceToOrigin float32
	PlaneNormal      vecmath.Vec3d

	// Due to the plane being infinite, it's impossible (or rather, it's
	// pointless) to determine its bounding box. So we allow specifying one
	// instead.
	AssignedBounds AABB
}

type Ray struct {
	Origin    vecmath.Vec3d
	Direction vecmath.Vec3d
}

type Sphere struct {
	TraceableBase

	SphereIntersectionInfo
}

type SphereIntersectionInfo struct {
	Pos    vecmath.Vec3d
	Radius float32
}

type Traceable interface {

	// Do we intersect ray? If so, return distance from ray origin to
	// point of intersection
	CheckIntersection(ray *Ray) (bool, float32)

	// Surface normal at given intersection point
	Normal(intersection *vecmath.Vec3d) vecmath.Vec3d

	Material() *Material

	Bounds() AABB
}

type TraceableBase struct {
	ObjectMaterial Material
}