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tayloraswifttayloraswift
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move definitions and add Noise suffix to public noise structs
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+235
-239
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5 files changed

+235
-239
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‎sources/noise/cell.swift

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
public
2-
struct Cell2D
2+
struct CellNoise2D:Noise
33
{
44

55
public

‎sources/noise/supersimplex.swift renamed to ‎sources/noise/gradient.swift

Lines changed: 231 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,215 @@
11
import func Glibc.sin
22
import func Glibc.cos
33

4+
fileprivate
5+
protocol GradientNoise2D:Noise
6+
{
7+
var permutation_table:PermutationTable { get }
8+
9+
static var gradient_table16:[(Double, Double)] { get }
10+
static var radius:Double { get }
11+
}
12+
13+
fileprivate
14+
extension GradientNoise2D
15+
{
16+
func gradient(u:Int, v:Int, dx:Double, dy:Double) -> Double
17+
{
18+
let dr:Double = Self.radius - dx*dx - dy*dy
19+
if dr > 0
20+
{
21+
let gradient:(Double, Double) = Self.gradient_table16[self.permutation_table.hash(u, v) & 15],
22+
drdr:Double = dr * dr
23+
return drdr * drdr * (gradient.0 * dx + gradient.1 * dy)
24+
}
25+
else
26+
{
27+
return 0
28+
}
29+
}
30+
}
31+
432
public
5-
struct SuperSimplex2D:GradientNoise2D
33+
struct SimplexNoise2D:GradientNoise2D
34+
{
35+
fileprivate static
36+
let gradient_table16:[(Double, Double)] =
37+
[
38+
(-1, -1), (1, 0), (-1, 0), (1, 1),
39+
(-1, 1), (0, -1), (0, 1), (1, -1),
40+
41+
(-1, -1), (1, 0), (-1, 0), (1, 1),
42+
(-1, 1), (0, -1), (0, 1), (1, -1)
43+
]
44+
45+
fileprivate static
46+
let radius:Double = 2
47+
48+
fileprivate
49+
let permutation_table:PermutationTable
50+
51+
private
52+
let amplitude:Double, // this is not necissaryly the same amplitude passed into the initializer
53+
frequency:Double
54+
55+
public
56+
init(amplitude:Double, frequency:Double, seed:Int = 0)
57+
{
58+
self.amplitude = 0.096 * amplitude
59+
self.frequency = frequency
60+
self.permutation_table = PermutationTable(seed: seed)
61+
}
62+
63+
public
64+
func evaluate(_ x:Double, _ y:Double) -> Double
65+
{
66+
let x:Double = x * self.frequency,
67+
y:Double = y * self.frequency
68+
// transform our coordinate system so that the *simplex* (x, y) forms a rectangular grid (u, v)
69+
let squish_offset:Double = (x + y) * SQUISH_2D,
70+
u:Double = x + squish_offset,
71+
v:Double = y + squish_offset
72+
73+
// get integral (u, v) coordinates of the rhombus
74+
let ub:Int = floor(u),
75+
vb:Int = floor(v)
76+
77+
// (0, 0) ----- (1, 0)
78+
// \ A / \
79+
// \ / \ ← (x, y) coordinates
80+
// \ / B \
81+
// (0, 1)-------(1, 1)
82+
83+
// (1, -1)
84+
// / |
85+
// / D |
86+
// / |
87+
// (ub, vb) = (0, 0) --- (1, 0) -- (2, 0)
88+
// / | / | /
89+
// / E | A / B | C / ← (u, v) coordinates
90+
// / | / | /
91+
// (-1, 1) -- (0, 1) --- (1, 1)
92+
// | /
93+
// | F /
94+
// | /
95+
// (0, 2)
96+
97+
// get relative position inside the rhombus relative to (ub, vb)
98+
let du0:Double = u - Double(ub),
99+
dv0:Double = v - Double(vb)
100+
101+
// do the same in the original (x, y) coordinate space
102+
103+
// stretch back to get (x, y) coordinates of rhombus origin
104+
let stretch_offset:Double = Double(ub + vb) * STRETCH_2D,
105+
xb:Double = Double(ub) + stretch_offset,
106+
yb:Double = Double(vb) + stretch_offset
107+
108+
// get relative position inside the rhombus relative to (xb, xb)
109+
let dx0:Double = x - xb,
110+
dy0:Double = y - yb
111+
112+
var Σ:Double = 0 // the value of the noise function, which we will sum up
113+
114+
// contribution from (1, 0)
115+
Σ += gradient(u : ub + 1,
116+
v : vb,
117+
dx: dx0 - 1 - STRETCH_2D,
118+
dy: dy0 - STRETCH_2D)
119+
120+
// contribution from (0, 1)
121+
Σ += gradient(u : ub,
122+
v : vb + 1,
123+
dx: dx0 - STRETCH_2D,
124+
dy: dy0 - 1 - STRETCH_2D)
125+
126+
// decide which triangle we are in
127+
let uv_sum:Double = du0 + dv0
128+
if (uv_sum > 1) // we are to the bottom-right of the diagonal line (du = 1 - dv)
129+
{
130+
Σ += gradient(u : ub + 1,
131+
v : vb + 1,
132+
dx: dx0 - 1 - 2*STRETCH_2D,
133+
dy: dy0 - 1 - 2*STRETCH_2D)
134+
135+
let center_dist:Double = 2 - uv_sum
136+
if center_dist < du0 || center_dist < dv0
137+
{
138+
if du0 > dv0
139+
{
140+
Σ += gradient(u : ub + 2,
141+
v : vb ,
142+
dx: dx0 - 2 - 2*STRETCH_2D,
143+
dy: dy0 - 2*STRETCH_2D)
144+
}
145+
else
146+
{
147+
Σ += gradient(u : ub ,
148+
v : vb + 2,
149+
dx: dx0 - 2*STRETCH_2D,
150+
dy: dy0 - 2 - 2*STRETCH_2D)
151+
}
152+
}
153+
else
154+
{
155+
Σ += gradient(u : ub,
156+
v : vb,
157+
dx: dx0,
158+
dy: dy0)
159+
}
160+
}
161+
else
162+
{
163+
Σ += gradient(u : ub,
164+
v : vb,
165+
dx: dx0,
166+
dy: dy0)
167+
168+
let center_dist:Double = 1 - uv_sum
169+
if center_dist > du0 || center_dist > dv0
170+
{
171+
if du0 > dv0
172+
{
173+
Σ += gradient(u : ub + 1,
174+
v : vb - 1,
175+
dx: dx0 + 1,
176+
dy: dy0 - 1)
177+
}
178+
else
179+
{
180+
Σ += gradient(u : ub - 1,
181+
v : vb + 1,
182+
dx: dx0 - 1,
183+
dy: dy0 + 1)
184+
}
185+
}
186+
else
187+
{
188+
Σ += gradient(u : ub + 1,
189+
v : vb + 1,
190+
dx: dx0 - 1 - 2*STRETCH_2D,
191+
dy: dy0 - 1 - 2*STRETCH_2D)
192+
}
193+
}
194+
195+
return self.amplitude * Σ
196+
}
197+
198+
public
199+
func evaluate(_ x:Double, _ y:Double, _:Double) -> Double
200+
{
201+
return self.evaluate(x, y)
202+
}
203+
204+
public
205+
func evaluate(_ x:Double, _ y:Double, _:Double, _:Double) -> Double
206+
{
207+
return self.evaluate(x, y)
208+
}
209+
}
210+
211+
public
212+
struct SuperSimplexNoise2D:GradientNoise2D
6213
{
7214
private
8215
struct LatticePoint
@@ -213,7 +420,7 @@ struct SuperSimplex2D:GradientNoise2D
213420
| - |
214421
| - |
215422
| - |
216-
u = 2v - 1 | - | u = 2v
423+
u = 2v - 1 | - | u = 2v
217424
| - |
218425
| - |
219426
(1, 0) -------------- (1, 1)
@@ -241,7 +448,7 @@ struct SuperSimplex2D:GradientNoise2D
241448
dy0:Double = dv0 + squish_offset
242449

243450
var Σ:Double = 0
244-
for point in SuperSimplex2D.points[base_vertex_index ..< base_vertex_index + 4]
451+
for point in SuperSimplexNoise2D.points[base_vertex_index ..< base_vertex_index + 4]
245452
{
246453
// get the relative offset from *that* particular point
247454
let dx:Double = dx0 - point.dx,
@@ -265,7 +472,7 @@ struct SuperSimplex2D:GradientNoise2D
265472
}
266473

267474
public
268-
struct SuperSimplex3D:GradientNoise3D
475+
struct SuperSimplexNoise3D:Noise
269476
{
270477
private
271478
struct LatticePoint
@@ -346,7 +553,7 @@ struct SuperSimplex3D:GradientNoise3D
346553
return points
347554
}()
348555

349-
static
556+
private static
350557
let gradient_table16:[(Double, Double, Double)] =
351558
[
352559
(1, 1, 0), (-1, 1, 0), (1, -1, 0), (-1, -1, 0),
@@ -355,6 +562,7 @@ struct SuperSimplex3D:GradientNoise3D
355562
(1, 1, 0), (-1, 1, 0), (0, -1, 1), (0, -1, -1)
356563
]
357564

565+
private
358566
let permutation_table:PermutationTable
359567

360568
private
@@ -369,6 +577,22 @@ struct SuperSimplex3D:GradientNoise3D
369577
self.permutation_table = PermutationTable(seed: seed)
370578
}
371579

580+
private
581+
func gradient(u:Int, v:Int, w:Int, dx:Double, dy:Double, dz:Double) -> Double
582+
{
583+
let dr:Double = 0.75 - dx*dx - dy*dy - dz*dz
584+
if dr > 0
585+
{
586+
let gradient:(Double, Double, Double) = SuperSimplexNoise3D.gradient_table16[self.permutation_table.hash(u, v, w) & 15],
587+
drdr:Double = dr * dr
588+
return drdr * drdr * (gradient.0 * dx + gradient.1 * dy + gradient.2 * dz)
589+
}
590+
else
591+
{
592+
return 0
593+
}
594+
}
595+
372596
public
373597
func evaluate(_ x:Double, _ y:Double) -> Double
374598
{
@@ -424,7 +648,7 @@ struct SuperSimplex3D:GradientNoise3D
424648

425649
// sum up the contributions from the two lattices
426650
var Σ:Double = 0
427-
for point in SuperSimplex3D.points[base_vertex_index1 ..< base_vertex_index1 + 4]
651+
for point in SuperSimplexNoise3D.points[base_vertex_index1 ..< base_vertex_index1 + 4]
428652
{
429653
// get the relative offset from *that* particular point
430654
let dx:Double = du1 - point.du,
@@ -433,7 +657,7 @@ struct SuperSimplex3D:GradientNoise3D
433657
Σ += self.gradient(u: ub1 + point.u, v: vb1 + point.v, w: wb1 + point.w, dx: dx, dy: dy, dz: dz)
434658
}
435659

436-
for point in SuperSimplex3D.points[base_vertex_index2 ..< base_vertex_index2 + 4]
660+
for point in SuperSimplexNoise3D.points[base_vertex_index2 ..< base_vertex_index2 + 4]
437661
{
438662
// get the relative offset from *that* particular point
439663
let dx:Double = du2 - point.du,

‎sources/noise/noise.swift

Lines changed: 0 additions & 51 deletions
Original file line numberDiff line numberDiff line change
@@ -89,57 +89,6 @@ struct PermutationTable
8989
}
9090
}
9191

92-
protocol GradientNoise2D:Noise
93-
{
94-
var permutation_table:PermutationTable { get }
95-
96-
static var gradient_table16:[(Double, Double)] { get }
97-
static var radius:Double { get }
98-
}
99-
100-
extension GradientNoise2D
101-
{
102-
func gradient(u:Int, v:Int, dx:Double, dy:Double) -> Double
103-
{
104-
let dr:Double = Self.radius - dx*dx - dy*dy
105-
if dr > 0
106-
{
107-
let gradient:(Double, Double) = Self.gradient_table16[self.permutation_table.hash(u, v) & 15],
108-
drdr:Double = dr * dr
109-
return drdr * drdr * (gradient.0 * dx + gradient.1 * dy)
110-
}
111-
else
112-
{
113-
return 0
114-
}
115-
}
116-
}
117-
118-
protocol GradientNoise3D:Noise
119-
{
120-
var permutation_table:PermutationTable { get }
121-
122-
static var gradient_table16:[(Double, Double, Double)] { get }
123-
}
124-
125-
extension GradientNoise3D
126-
{
127-
func gradient(u:Int, v:Int, w:Int, dx:Double, dy:Double, dz:Double) -> Double
128-
{
129-
let dr:Double = 0.75 - dx*dx - dy*dy - dz*dz
130-
if dr > 0
131-
{
132-
let gradient:(Double, Double, Double) = Self.gradient_table16[self.permutation_table.hash(u, v, w) & 15],
133-
drdr:Double = dr * dr
134-
return drdr * drdr * (gradient.0 * dx + gradient.1 * dy + gradient.2 * dz)
135-
}
136-
else
137-
{
138-
return 0
139-
}
140-
}
141-
}
142-
14392
public
14493
struct fBm<Generator:Noise>:Noise
14594
{

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