Commit ee98ab32fdda5ab40f79756172e19afe0abc12c4 - monte

Add monte carlo antialiasing and configurable sky color Will Brown 9 years ago

4 changed file(s) with 55 addition(s) and 24 deletion(s). Raw diff Collapse all Expand all

-9

src/main.go less more

24	24	Look: monte.NewRay(monte.Vect(0, 0, 0), monte.Vect(0, 0, 1)),
25	25	U1: monte.Vect(1, 0, 0),
26	26	U2: monte.Vect(0, 1, 0),
27		FDist: 1}
	27	FDist: 1,
	28	Sky: monte.NewColor(0, 200, 255, 255),
	29	Oversample: 8,
	30	}
28	31
29	32	img := image.NewNRGBA(image.Rect(0, 0, Width, Height))
30		w, h := float64(Width), float64(Height)
31		for i := 0; i < *Width; i++ {
32		u := (float64(i) - w / 2.0) / (w / 2.0)
33		for j := 0; j < *Height; j++ {
34		v := (float64(j) - h / 2.0) / (h / 2.0)
35		go scene.SetColor(i, j, u, v, img)
36		}
37		}
	33	scene.Render(img)
38	34
39	35	out, err := os.Create(*Output)
40	36	if err != nil {

+45

-14

src/monte/scene.go less more

3	3	"image"
4	4	"image/color"
5	5	"math"
	6	"math/rand"
6	7	)
7	8
8		func NewColor(r, g, b, a uint8) color.Color {
	9	func NewColor(r, g, b, a uint8) color.NRGBA {
9	10	return color.NRGBA{R: r, G: g, B: b, A: a}
10	11	}
11	12

16	17	// scan to fill in the picture
17	18	U1, U2 *Vector
18	19	FDist float64
	20	Sky color.NRGBA
	21	Oversample int
19	22	}
20	23
21	24	func (s Scene) DirectionAt(u, v float64) Vector {

24	27	}
25	28
26	29	func (s *Scene) ColorAt(u, v float64) color.Color {
27		ray := NewRay(s.Look.Origin, s.DirectionAt(u, v))
	30	var r, g, b, n int32 = 0, 0, 0, 0
	31	sr, sg, sb := s.Sky.R, s.Sky.G, s.Sky.B
28	32
29		minDist := math.Inf(1)
30		var minGeom *Primitive = nil
	33	for i := 0; i < s.Oversample; i++ {
	34	du := (rand.Float64() - 0.5) / 200
	35	dv := (rand.Float64() - 0.5) / 200
	36	ray := NewRay(s.Look.Origin, s.DirectionAt(u+du, v+dv))
31	37
32		for _, geom := range s.Geom {
33		i, d := geom.Intersect(ray)
34		if i != nil && d < minDist {
35		minDist = d
36		minGeom = &geom
	38	minDist := math.Inf(1)
	39	var minGeom *Primitive = nil
	40
	41	for _, geom := range s.Geom {
	42	i, d := geom.Intersect(ray)
	43	if i != nil && d < minDist {
	44	minDist = d
	45	minGeom = &geom
	46	}
37	47	}
	48
	49	if minGeom != nil {
	50	r += 255
	51	g += 255
	52	b += 255
	53	} else {
	54	r += int32(sr)
	55	g += int32(sg)
	56	b += int32(sb)
	57	}
	58	n++
38	59	}
39
40		if minGeom != nil {
41		return NewColor(255, 255, 255, 255)
42		}
43		return NewColor(0, 0, 0, 255)
	60	return NewColor(uint8(r / n), uint8(g / n), uint8(b / n), 255)
44	61	}
45	62
46	63	func (s Scene) SetColor(i, j int, u, v float64, img image.NRGBA) {
47	64	img.Set(i, j, s.ColorAt(u, v))
48	65	}
	66
	67	func (s Scene) Render(img image.NRGBA) {
	68	rect := img.Bounds()
	69	w, h := float64(rect.Dx()), float64(rect.Dy())
	70	i_max, j_max := rect.Dx(), rect.Dy()
	71	for i := 0; i < i_max; i++ {
	72	u := (float64(i) - w / 2.0) / (w / 2.0)
	73	for j := 0; j < j_max; j++ {
	74	// (h / w) term is needed to correct for nonunity aspect ratios
	75	v := (float64(j) - h / 2.0) / (h / 2.0) * (h / w)
	76	go s.SetColor(i, j, u, v, img)
	77	}
	78	}
	79	}

-1

src/monte/sphere.go less more

41	41	}
42	42
43	43	func (s Sphere) Normal(loc Vector) Vector {
44		return Vect(0, 0, 0)
	44	return loc.Sub(s.Center).NormalizeInPlace()
45	45	}

-0

src/monte/vector.go less more

13	13
14	14	func (v Vector) Add(w Vector) *Vector {
15	15	return &Vector{X: v.X + w.X, Y: v.Y + w.Y, Z: v.Z + w.Z}
	16	}
	17
	18	func (v Vector) Sub(w Vector) *Vector {
	19	return &Vector{X: v.X - w.X, Y: v.Y - w.Y, Z: v.Z - w.Z}
16	20	}
17	21
18	22	func (v Vector) Copy() Vector {