diff --git a/README.md b/README.md index 43d8014..725c7a3 100644 --- a/README.md +++ b/README.md @@ -1,4 +1,2 @@ Simple cpu ray-marching in go Focus on Lisiblity & Features - - \ No newline at end of file diff --git a/src/primitives_sdf.go b/src/primitives_sdf.go index 12eebf3..ba173ab 100644 --- a/src/primitives_sdf.go +++ b/src/primitives_sdf.go @@ -6,12 +6,8 @@ type Sphere struct { material Material } -func (s Sphere) Distance(p Vector3) float64 { - return p.Length() - s.radius -} - -func (s Sphere) GetMaterial(p Vector3) Material { - return s.material +func (s Sphere) Distance(p Vector3) (float64, Material) { + return p.Length() - s.radius, s.material } // Box @@ -20,13 +16,9 @@ type Box struct { material Material } -func (s Box) Distance(p Vector3) float64 { +func (s Box) Distance(p Vector3) (float64, Material) { q := p.Abs().Sub(s.dimensions) - return q.Max(0.0).Length() + min(max(q.X, max(q.Y, q.Z)), 0.0) -} - -func (s Box) GetMaterial(p Vector3) Material { - return s.material + return q.Max(0.0).Length() + min(max(q.X, max(q.Y, q.Z)), 0.0), s.material } // Plane @@ -35,10 +27,6 @@ type Plane struct { material Material } -func (s Plane) Distance(p Vector3) float64 { - return p.Dot(s.normal) -} - -func (s Plane) GetMaterial(p Vector3) Material { - return s.material +func (s Plane) Distance(p Vector3) (float64, Material) { + return p.Dot(s.normal), s.material } diff --git a/src/ray_marching.go b/src/ray_marching.go index 0cf1b17..8a8aec7 100644 --- a/src/ray_marching.go +++ b/src/ray_marching.go @@ -30,7 +30,7 @@ func shadow(point Vector3) float64 { res := 1.0 dist_total := 0.0 for range MAX_STEP { - dist := scene.Distance(p) + dist, _ := scene.Distance(p) if dist < EPS { return 0 } @@ -62,9 +62,8 @@ func reflect(point Vector3, direction Vector3, normal Vector3, mat Material, ref func rayMarch(origin Vector3, direction Vector3, reflectNumber int) (bool, Vector3) { p := origin for range MAX_STEP { - dist := scene.Distance(p) + dist, mat := scene.Distance(p) if dist < EPS { - mat := scene.GetMaterial(p) normal := Gradient(scene, p, EPS).Normalized() phongShade := phongShading(p, normal, mat) shadowCoeff := max(shadow(p), 0.3) diff --git a/src/sdf.go b/src/sdf.go index f41ae66..c57df23 100644 --- a/src/sdf.go +++ b/src/sdf.go @@ -5,14 +5,18 @@ import ( ) type SDF interface { - Distance(Vector3) float64 - GetMaterial(Vector3) Material + Distance(Vector3) (float64, Material) +} + +func DistanceOnly(sdf SDF, p Vector3) float64 { + dist, _ := sdf.Distance(p) + return dist } func Gradient(sdf SDF, p Vector3, eps float64) Vector3 { - dx := (sdf.Distance(p.Add(Vector3{X: eps})) - sdf.Distance(p.Add(Vector3{X: -eps}))) / (2 * eps) - dy := (sdf.Distance(p.Add(Vector3{Y: eps})) - sdf.Distance(p.Add(Vector3{Y: -eps}))) / (2 * eps) - dz := (sdf.Distance(p.Add(Vector3{Z: eps})) - sdf.Distance(p.Add(Vector3{Z: -eps}))) / (2 * eps) + dx := (DistanceOnly(sdf, p.Add(Vector3{X: eps})) - DistanceOnly(sdf, p.Add(Vector3{X: -eps}))) / (2 * eps) + dy := (DistanceOnly(sdf, p.Add(Vector3{Y: eps})) - DistanceOnly(sdf, p.Add(Vector3{Y: -eps}))) / (2 * eps) + dz := (DistanceOnly(sdf, p.Add(Vector3{Z: eps})) - DistanceOnly(sdf, p.Add(Vector3{Z: -eps}))) / (2 * eps) return Vector3{X: dx, Y: dy, Z: dz} } @@ -23,40 +27,29 @@ type TranslatedSDF struct { translate Vector3 } -func (s TranslatedSDF) Distance(p Vector3) float64 { +func (s TranslatedSDF) Distance(p Vector3) (float64, Material) { return s.primitive.Distance(p.Sub(s.translate)) } -func (s TranslatedSDF) GetMaterial(p Vector3) Material { - return s.primitive.GetMaterial(p.Sub(s.translate)) -} - type RotatedSDF struct { primitive SDF rotVector Vector3 angle float64 } -func (s RotatedSDF) Distance(p Vector3) float64 { +func (s RotatedSDF) Distance(p Vector3) (float64, Material) { rotated_p := Rotate(p, s.rotVector, s.angle) return s.primitive.Distance(rotated_p) } -func (s RotatedSDF) GetMaterial(p Vector3) Material { - rotated_p := Rotate(p, s.rotVector, s.angle) - return s.primitive.GetMaterial(rotated_p) -} type ScaledSDF struct { primitive SDF scale float64 } -func (s ScaledSDF) Distance(p Vector3) float64 { - return s.primitive.Distance(p.Scale(1 / s.scale)) -} - -func (s ScaledSDF) GetMaterial(p Vector3) Material { - return s.primitive.GetMaterial(p.Scale(1 / s.scale)) +func (s ScaledSDF) Distance(p Vector3) (float64, Material) { + dist, color := s.primitive.Distance(p.Scale(1 / s.scale)) + return dist * s.scale, color } type RepeatSDF struct { @@ -64,39 +57,29 @@ type RepeatSDF struct { cellSize Vector3 } -func (s RepeatSDF) Distance(p Vector3) float64 { +func (s RepeatSDF) Distance(p Vector3) (float64, Material) { x, y, z := p.Unpack() sx, sy, sz := s.cellSize.Unpack() round := math.RoundToEven nearest_cell := Vector3{sx * round(x/sx), sy * round(y/sy), sz * round(z/sz)} return s.primitive.Distance(p.Sub(nearest_cell)) } -func (s RepeatSDF) GetMaterial(p Vector3) Material { - x, y, z := p.Unpack() - sx, sy, sz := s.cellSize.Unpack() - round := math.RoundToEven - nearest_cell := Vector3{sx * round(x/sx), sy * round(y/sy), sz * round(z/sz)} - return s.primitive.GetMaterial(p.Sub(nearest_cell)) -} type UnionSDF struct { primitive1 SDF primitive2 SDF } -func (s UnionSDF) Distance(p Vector3) float64 { - return min(s.primitive1.Distance(p), s.primitive2.Distance(p)) -} - -func (s UnionSDF) GetMaterial(p Vector3) Material { - d1, color1 := s.primitive1.Distance(p), s.primitive1.GetMaterial(p) - d2, color2 := s.primitive2.Distance(p), s.primitive2.GetMaterial(p) +func (s UnionSDF) Distance(p Vector3) (float64, Material) { + d1, color1 := s.primitive1.Distance(p) + d2, color2 := s.primitive2.Distance(p) + d := min(d1, d2) color := color1 if d2 < d1 { color = color2 } - return color + return d, color } type SubstractionSDF struct { @@ -104,12 +87,12 @@ type SubstractionSDF struct { primitive2 SDF } -func (s SubstractionSDF) Distance(p Vector3) float64 { - return max(s.primitive1.Distance(p), -s.primitive2.Distance(p)) -} +func (s SubstractionSDF) Distance(p Vector3) (float64, Material) { + d1, color1 := s.primitive1.Distance(p) + d2, _ := s.primitive2.Distance(p) -func (s SubstractionSDF) GetMaterial(p Vector3) Material { - return s.primitive1.GetMaterial(p) + d := max(d1, -d2) + return d, color1 } type IntersectionSDF struct { @@ -117,13 +100,14 @@ type IntersectionSDF struct { primitive2 SDF } -func (s IntersectionSDF) Distance(p Vector3) float64 { - return max(s.primitive1.Distance(p), s.primitive2.Distance(p)) -} +func (s IntersectionSDF) Distance(p Vector3) (float64, Material) { -func (s IntersectionSDF) GetMaterial(p Vector3) Material { - mat1, mat2 := s.primitive1.GetMaterial(p), s.primitive2.GetMaterial(p) - return MixedMaterial{mat1, mat2, 0.5, p} + d1, mat1 := s.primitive1.Distance(p) + d2, mat2 := s.primitive2.Distance(p) + d := max(d1, d2) + + var mat Material = MixedMaterial{mat1, mat2, 0.5, p} + return d, mat } type SmoothUnionSDF struct { @@ -132,20 +116,15 @@ type SmoothUnionSDF struct { k float64 } -func (s SmoothUnionSDF) Distance(p Vector3) float64 { +func (s SmoothUnionSDF) Distance(p Vector3) (float64, Material) { k := 4 * s.k - d1 := s.primitive1.Distance(p) - d2 := s.primitive2.Distance(p) + d1, mat1 := s.primitive1.Distance(p) + d2, mat2 := s.primitive2.Distance(p) h := max(k-math.Abs(d1-d2), 0.0) - return min(d1, d2) - h*h*0.25/k -} - -func (s SmoothUnionSDF) GetMaterial(p Vector3) Material { - k := 4 * s.k - d1, mat1 := s.primitive1.Distance(p), s.primitive1.GetMaterial(p) - d2, mat2 := s.primitive2.Distance(p), s.primitive2.GetMaterial(p) + d := min(d1, d2) - h*h*0.25/k t := SmoothStep(d2-d1, -k, k) - return MixedMaterial{mat2, mat1, t, p} + var mat Material = MixedMaterial{mat2, mat1, t, p} + return d, mat } type SmoothSubstractionSDF struct { @@ -154,20 +133,15 @@ type SmoothSubstractionSDF struct { k float64 } -func (s SmoothSubstractionSDF) Distance(p Vector3) float64 { +func (s SmoothSubstractionSDF) Distance(p Vector3) (float64, Material) { k := 4 * s.k - d1 := s.primitive1.Distance(p) - d2 := s.primitive2.Distance(p) + d1, mat1 := s.primitive1.Distance(p) + d2, mat2 := s.primitive2.Distance(p) h := max(k-math.Abs(-d1-d2), 0.0) - return max(d1, -d2) + h*h*0.25/k -} - -func (s SmoothSubstractionSDF) GetMaterial(p Vector3) Material { - k := 4 * s.k - d1, mat1 := s.primitive1.Distance(p), s.primitive1.GetMaterial(p) - d2, mat2 := s.primitive2.Distance(p), s.primitive2.GetMaterial(p) + d := max(d1, -d2) + h*h*0.25/k t := SmoothStep(d1-d2, -k, k) - return MixedMaterial{mat1, mat2, t, p} + var mat Material = MixedMaterial{mat1, mat2, t, p} + return d, mat } type SmoothIntersectionSDF struct { @@ -176,18 +150,13 @@ type SmoothIntersectionSDF struct { k float64 } -func (s SmoothIntersectionSDF) Distance(p Vector3) float64 { +func (s SmoothIntersectionSDF) Distance(p Vector3) (float64, Material) { k := 4 * s.k - d1 := s.primitive1.Distance(p) - d2 := s.primitive2.Distance(p) + d1, mat1 := s.primitive1.Distance(p) + d2, mat2 := s.primitive2.Distance(p) h := max(k-math.Abs(d1-d2), 0.0) - return max(d1, d2) + h*h*0.25/k -} - -func (s SmoothIntersectionSDF) GetMaterial(p Vector3) Material { - k := 4 * s.k - d1, mat1 := s.primitive1.Distance(p), s.primitive1.GetMaterial(p) - d2, mat2 := s.primitive2.Distance(p), s.primitive2.GetMaterial(p) + d := max(d1, d2) + h*h*0.25/k t := SmoothStep(d2-d1, -k, k) - return MixedMaterial{mat1, mat2, t, p} + var mat Material = MixedMaterial{mat1, mat2, t, p} + return d, mat }