1642 Stacks

(wash colour:  {(col/rgb r: 0.596 g: 0.316 b: 0.625 alpha: 0.010) (gen/col)})
(tri-hsl alpha: {0.997 (gen/scalar)})
(tri-lab alpha: {0.931 (gen/scalar)})

(fn (tri-lab alpha: 1)
  (define
    w 86.6
    h 50
    r (prng/build min: 0 max: 1 seed: 231)
    colour-scale {721 (gen/int max: 900)}
    colour-offset (prng/build min: -1 max: 1)
    li (interp/build from: [0 1]
                     to: [{119 (gen/int min: 0 max: 120)}
                          {12 (gen/int min: 0 max: 120)}])
    rma (interp/build from: [0 canvas/width]
                      to: [{84 (gen/int min: -100 max: 100)}
                           {-13 (gen/int min: -100 max: 100)}])
    rmb (interp/build from: [0 canvas/height]
                      to: [{95 (gen/int min: -120 max: 120)}
                           {-38 (gen/int min: -120 max: 120)}]))

  (loop (y from: 0 upto: canvas/height inc: 30)
    !(loop (x from: 0 upto: canvas/width inc: (* 2 w))
      (define
        a (interp/value from: rma t: (+ x (* (prng/value from: colour-offset) colour-scale)))
        b (interp/value from: rmb t: (+ y (* (prng/value from: colour-offset) colour-scale))))
      (poly coords: [[x (+ y 0)]
                     [(+ x w) (+ y h)]
                     [x (+ y h h)]]
            colours: [(col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)])
      (poly coords: [[x (+ y 0)]
                     [(+ x w) (+ y h)]
                     [(+ x w) (- y h)]]
            colours: [(col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)]))

    (loop (x from: w upto: canvas/width inc: (* 2 w))
      (define
        a (interp/value from: rma t: (+ x (* (prng/value from: colour-offset) colour-scale)))
        b (interp/value from: rmb t: (+ y (* (prng/value from: colour-offset) colour-scale))))

      (poly coords: [[x (+ y h)]
                     [(+ x w) (+ y h h)]
                     [(+ x w) (+ y 0)]]
            colours: [(col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)])
      (poly coords: [[x (+ y h)]
                     [(+ x w) (+ y 0)]
                     [x (- y h)]]
            colours: [(col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)
                      (col/lab l: (interp/value from: li t: (prng/value from: r)) a: a b: b alpha: alpha)]))))

(fn (tri-hsl alpha: 1)
  (define
    w 86.6
    h 50
    colour-scale {644 (gen/int max: 900)}
    colour-offset (prng/build min: -1 max: 1)
    fn-h (interp/build from: [0 canvas/width]
                       to: [{244 (gen/int max: 360)}
                            {357 (gen/int max: 360)}])
    fn-l (interp/build from: [0 canvas/height]
                       to: [{0.427 (gen/scalar min: 0.2 max: 0.5)}
                            {0.462 (gen/scalar min: 0.4 max: 1)}]))
  (loop (y from: 0 upto: canvas/height inc: 30)
    (loop (x from: 0 upto: canvas/width inc: (* 2 w))
      (define
        a (interp/value from: fn-h t: (+ x (* (prng/value from: colour-offset) colour-scale)))
        b (interp/value from: fn-l t: (+ y (* (prng/value from: colour-offset) colour-scale))))

      (poly coords: [[x (+ y 0)]
                     [(+ x w) (+ y h)]
                     [x (+ y h h)]]
            colours: [(col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)])
      (poly coords: [[x (+ y 0)]
                     [(+ x w) (+ y h)]
                     [(+ x w) (- y h)]]
            colours: [(col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)]))

    (loop (x from: w upto: canvas/width inc: (* 2 w))
      (define
        a (interp/value from: fn-h t: (+ x (* (prng/value from: colour-offset) colour-scale)))
        b (interp/value from: fn-l t: (+ y (* (prng/value from: colour-offset) colour-scale))))

      (poly coords: [[x (+ y h)]
                     [(+ x w) (+ y h h)]
                     [(+ x w) (+ y 0)]]
            colours: [(col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)])
      (poly coords: [[x (+ y h)]
                     [(+ x w) (+ y 0)]
                     [x (- y h)]]
            colours: [(col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)
                      (col/hsl h: a s: 1 l: b alpha: alpha)]))))

(fn (wash vol: 200
          line-width: 70
          line-segments: 5
          colour: (col/rgb r: 0.627 g: 0.627 b: 0.627 alpha: 0.4)
          seed: 272)
  (define
    w/3 (/ canvas/width 3)
    h/3 (/ canvas/height 3))
  (loop (d from: -20 to: 1020 inc: 20)
    (bezier tessellation: line-segments
            line-width: line-width
            coords: [[0            (wash-n x: 0            d: d seed: seed vol: vol)]
                     [w/3          (wash-n x: w/3          d: d seed: seed vol: vol)]
                     [(* w/3 2)    (wash-n x: (* w/3 2)    d: d seed: seed vol: vol)]
                     [canvas/width (wash-n x: canvas/width d: d seed: seed vol: vol)]]
            colour: colour)

    (bezier tessellation: line-segments
            line-width: line-width
            coords: [[(wash-n x: 0             d: d seed: seed vol: vol) 0]
                     [(wash-n x: h/3           d: d seed: seed vol: vol) h/3]
                     [(wash-n x: (* h/3 2)     d: d seed: seed vol: vol) (* h/3 2)]
                     [(wash-n x: canvas/height d: d seed: seed vol: vol) canvas/height]]
            colour: colour)))

(fn (wash-n x: 0 d: 0 seed: 0 vol: 1)
  (+ d (* vol (prng/perlin x: x y: d z: seed))))