README
¶
gotrace
gotrace is a Golang implementation of Peter Shirley's excellent books on raytracing.
I used it as a way to better understand Go interfaces. Being more familiar with object-oriented languages, I wondered how polymorphism behaviour could be implemented without inheritance. Turns out it is pretty awesome !
Pros
- Strong concurrency primitives. Using weighted semaphores is a very intuitive way to create a workgroup.
- Interfaces feels like more natural way to provide polymorphism behaviour at runtime, compared to inheritance.
- Awesome self-documentation
Cons
- No operator overloading
corner := lookFrom.Sub(u.Scale(width * focusDist)).Sub(v.Scale(height * focusDist)).Sub(w.Scale(focusDist))
would have been clearer as
corner := lookfrom - u*width*focusDist - v*height*focusDist - w*focusDist
- No forward declarations
Actor needs to know about Shape, Material and Ray, but Shape also has to know about Ray, so they can't live in different packages without having to add unecessary complexity, because Go doesn't support forward declarations and can't resolve "circular" dependencies.
Credits
Documentation
¶
Overview ¶
Package gotrace is a simple raytracer inspired by Peter Shirley's books.
package main
import "github.com/teobouvard/gotrace"
func main() {
scene := gotrace.BookScene()
scene.Render(400, -1, 500, 50)
}
Index ¶
- Variables
- type Actor
- type Bbox
- type Box
- type Camera
- type CheckerTexture
- type Collection
- type ConstantTexture
- type Dielectric
- type DiffuseLight
- type FlipFace
- type Fog
- type Geometry
- type HitRecord
- type Image
- type Index
- type Isotropic
- type Lambertian
- type Marble
- type Material
- type Metal
- type MovingSphere
- type Noise
- type Ray
- type RectXY
- type RectXZ
- type RectYZ
- type RotateY
- type Scene
- type Sphere
- type Texture
- type Translate
- type Vec3
- func (u Vec3) Add(v Vec3) Vec3
- func (u Vec3) AsArray() [3]float64
- func (u Vec3) Cross(v Vec3) Vec3
- func (u Vec3) Div(t float64) Vec3
- func (u Vec3) Dot(v Vec3) float64
- func (u Vec3) GetColor(samples int) color.RGBA
- func (u Vec3) Mul(v Vec3) Vec3
- func (u Vec3) Neg() Vec3
- func (u Vec3) Norm() float64
- func (u Vec3) Reflect(n Vec3) Vec3
- func (u Vec3) Refract(n Vec3, nRatio float64) (bool, Vec3)
- func (u Vec3) Scale(t float64) Vec3
- func (u Vec3) SquareNorm() float64
- func (u Vec3) Sub(v Vec3) Vec3
- func (u Vec3) Unit() Vec3
Constants ¶
This section is empty.
Variables ¶
var ( BLACK = Vec3{0, 0, 0} WHITE = Vec3{1, 1, 1} RED = Vec3{1, 0, 0} GREEN = Vec3{0, 1, 0} BLUE = Vec3{0, 0, 1} )
Colors
Functions ¶
This section is empty.
Types ¶
type Actor ¶
type Actor struct {
// contains filtered or unexported fields
}
Actor is an object on the scene having a shape and a material
type Bbox ¶
Bbox is a bounding box of a geometry
type Box ¶ added in v0.2.0
type Box struct {
// contains filtered or unexported fields
}
Box is a cube
type Camera ¶
type Camera struct {
AspectRatio float64
// contains filtered or unexported fields
}
A Camera is the eye through which the the scene is observed
type CheckerTexture ¶
type CheckerTexture struct {
// contains filtered or unexported fields
}
CheckerTexture is a checkboard-like texture
type Collection ¶
type Collection []Actor
A Collection is a group of Actors
func (*Collection) Add ¶
func (c *Collection) Add(actors ...Actor)
Add appends new Actors to the collection
func (Collection) Bound ¶
func (c Collection) Bound(tMin float64, tMax float64) (bool, *Bbox)
Bound computes the bounding box of a Collection
func (Collection) Comparator ¶
func (c Collection) Comparator(startTime, endTime float64, axis int) func(i, j int) bool
Comparator returns a comparison function of objects in the collection along the given axis. Used for Index sorting.
type ConstantTexture ¶
type ConstantTexture struct {
// contains filtered or unexported fields
}
ConstantTexture is a uniform texture with a single color
type Dielectric ¶
type Dielectric struct {
// contains filtered or unexported fields
}
Dielectric is a glass-like material
type DiffuseLight ¶ added in v0.2.0
type DiffuseLight struct {
// contains filtered or unexported fields
}
DiffuseLight is a light-emitting material
type FlipFace ¶ added in v0.2.0
type FlipFace struct {
// contains filtered or unexported fields
}
FlipFace is a geometry wrapper for flipping the front face of the wrapped geometry
type Fog ¶ added in v0.2.0
type Fog struct {
// contains filtered or unexported fields
}
Fog is a volumetric medium
type Geometry ¶
type Geometry interface {
Hit(ray Ray, tMin float64, tMax float64) (bool, *HitRecord)
Bound(startTime float64, endTime float64) (bool, *Bbox)
}
Geometry interface
Hit ¶
@in
ray : a light ray tMin : closer objects are not considered tMax : further objects are not considered
@out
bool : if the ray hit the geometry HitRecord : information about the hit, or nil
Bound ¶
@in
startTime : the starting time for bounding endTime : the ending time for bounding
@out
bool : if the geometry can be bounded (false for infinite planes) Bbox : bounding box (aabb) of the geometry, if applicable
func NewRotateY ¶ added in v0.2.0
NewRotateY constructs a rotated object around the Y axis
type Image ¶ added in v0.2.0
type Image struct {
// contains filtered or unexported fields
}
Image is a texture mapped to an image file
type Index ¶
type Index struct {
// contains filtered or unexported fields
}
Index is a binary tree forming a bounding volume hierarchy of objects satisfying the geometry interface
func NewIndex ¶
func NewIndex(world Collection, start, end int, startTime, endTime float64) *Index
NewIndex builds a bounding volume hierarchy
type Isotropic ¶ added in v0.2.0
type Isotropic struct {
// contains filtered or unexported fields
}
Isotropic is a material scattering in random direction
type Lambertian ¶
type Lambertian struct {
// contains filtered or unexported fields
}
Lambertian is a diffuse material
type Marble ¶ added in v0.2.0
type Marble struct {
// contains filtered or unexported fields
}
Marble is a marble-like texture
type Material ¶
type Material interface {
Scatter(ray Ray, hit HitRecord) (bool, Vec3, Ray)
Emit(u, v float64, pos Vec3) Vec3
}
Material define the way actors interact with a ray
Scatter ¶
@in
ray : an incident ray hit : the record for the hit of the ray with a geometry
@out
bool : true if the material scatters the ray Vec3 : the attenuation of the scattered ray Ray : the scattered ray
type Metal ¶
type Metal struct {
// contains filtered or unexported fields
}
Metal is a reflective material
type MovingSphere ¶
type MovingSphere struct {
CenterStart Vec3
CenterStop Vec3
Radius float64
// contains filtered or unexported fields
}
MovingSphere geometry
type Noise ¶ added in v0.2.0
type Noise struct {
// contains filtered or unexported fields
}
Noise is an opensimplex noise
type RectXY ¶ added in v0.2.0
type RectXY struct {
// contains filtered or unexported fields
}
RectXY is a rectangular shape in the XY plane (z=k), bounded by x0, x1, y0 and y1
type RectXZ ¶ added in v0.2.0
type RectXZ struct {
// contains filtered or unexported fields
}
RectXZ is a rectangular shape in the XZ plane (y=k), bounded by x0, x1, z0 and z1
type RectYZ ¶ added in v0.2.0
type RectYZ struct {
// contains filtered or unexported fields
}
RectYZ is a rectangular shape in the YZ plane (x=k), bounded by y0, y1, z0 and z1
type RotateY ¶ added in v0.2.0
type RotateY struct {
// contains filtered or unexported fields
}
RotateY is a wrapper around a geometry, which is rotated around the Y axis
type Scene ¶
type Scene struct {
// contains filtered or unexported fields
}
Scene is the whole scene to be rendered
func CornellBox ¶ added in v0.2.0
func CornellBox() *Scene
CornellBox is a the classic cornell box scene
func EarthScene ¶ added in v0.2.0
func EarthScene() *Scene
EarthScene is a scene demonstrating image textures
func FinalScene ¶ added in v0.2.0
func FinalScene() *Scene
FinalScene is the last scene of Ray Tracing: The Next Week
func FoggyCornellBox ¶ added in v0.2.0
func FoggyCornellBox() *Scene
FoggyCornellBox is a the cornell box scene with fog objects
func LightMarbleScene ¶ added in v0.2.0
func LightMarbleScene() *Scene
LightMarbleScene is a scene with a black and white marble with lights
func MarbleScene ¶ added in v0.2.0
func MarbleScene() *Scene
MarbleScene is a scene with a black and white marble
func MovingSpheres ¶
func MovingSpheres() *Scene
MovingSpheres creates the scene on the cover of the first book, with bouncing balls
type Texture ¶
Texture interface
Value ¶
@in
u, v : coordinates of the point
@out
Vec3 : color at the given coordinates
type Translate ¶ added in v0.2.0
type Translate struct {
// contains filtered or unexported fields
}
Translate is a wrapper around a geometry, which is offset by a translation vector
type Vec3 ¶
type Vec3 struct {
X, Y, Z float64
}
Vec3 defines a 3-dimensional vector
func MaxCoord ¶ added in v0.2.0
MaxCoord returns a new vector corresponding to the element-wise maximum of the two vectors
func MinCoord ¶ added in v0.2.0
MinCoord returns a new vector corresponding to the element-wise minimum of the two vectors
func RandSphere ¶
RandSphere returns vector drawn from a lambertian distribution inside the unit sphere
func RandVecInterval ¶
RandVecInterval returns a random vector with coordinates in [low, high)
func (Vec3) SquareNorm ¶
SquareNorm returns the square of the euclidean norm of u
Source Files
Directories