Beads on vector fields source

beads.clj

(ns gen-art.beads
    (:require [clojure2d.core :refer :all]
              [fastmath.core :as m]
              [fastmath.random :as r]
              [fastmath.fields :as f]
              [fastmath.vector :as v]
              [clojure2d.color :as c]
              [clojure2d.extra.utils :as ut]
              [clojure2d.pixels :as p])
    (:import [fastmath.vector Vec2]) )

(set! *warn-on-reflection* true)
(set! *unchecked-math* :warn-on-boxed)
(m/use-primitive-operators)

(def ^:const ^double sp3 (m/sin m/THIRD_PI))
(def ^:const ^long slotsx 110)

(def ^:const ^double w 900)
(def ^:const ^double h 400)


;; vector field dimensions
(def ^:const ^double bx (* 4.0 w (/ 1.0 (min h w))) ) 
(def ^:const ^double by (* 4.0 h (/ 1.0 (min h w))) )


;; center offset of vector field
(def ^:const ^Vec2 coff (Vec2. (- (/ bx 2.0)) (- (/ by 2)) ))

(def ^:const ^double edge (/ bx slotsx))


(def ^:const ^long slotsy (Math/round  (/ h (* sp3 (/ w slotsx)) )))



(def pal (nth c/colourlovers-palettes (r/irand  (count c/colourlovers-palettes) )))
(def bw-pal-1 [0x29292e 0xf9f9fa 0x9c9ca0 ])
(def bw-pal-2 [(v/vec4 30 30 30 255) (v/vec4 180 180 180 255)  :white])
(def fld (f/combine (f/random-configuration 3)))
;;(def fld (f/field :swirl))

;(ut/show-palette bw-pal-1)
(def art-pal  (nth c/colourlovers-palettes 146))


(defn p-grad [p x]
  (let [c (- (count p) 1)
        i (Math/round (* c x))
        idx (if (> i c) c i)]
    (nth p idx)))
    
(def grad (partial p-grad art-pal))


(defn idx-to-vec [^long idx]
  (let [r (quot idx slotsx)
        c (mod idx slotsx)
        e (/ bx slotsx)
       
        offset (if (odd? r) (* e 0.5) 0.0)
        x (+ (* c e) offset)
        y (* r sp3 e)
        ]
    (Vec2. x y)))


(defn vec-to-idx [^Vec2 v]
  (let [x (.x v)
        y (.y v)
        e (/ bx slotsx)
        he (* e 0.5)
        h (* sp3 e)
        r (Math/round (/ y h))
        x' (if (odd? r) (- x he) x)
        c (Math/round (/ x' e))]
    (+ c (* r slotsx))
    ))

(defn to-screenv [^Vec2 p]
  (let [fact (/ w bx)]
    (v/mult p fact)))



(defn field [^Vec2 p]
  (let [v (v/mult  (v/normalize (fld (v/add p coff))) edge)]
    (v/add p v)))




(defn in-bounds [[^double x ^double y]]
  (and (pos? x) (pos? y) (< x bx) (< y by)))



(defn step [p c sl]
  (let [p' (field p)
        i (vec-to-idx p')]
    (if (and (in-bounds p') (contains? (set sl) i))
      [c i p']
      [(r/drand 0.0 1.0) (first sl) (idx-to-vec (first sl))])))
      



(defn make-me
  
  [canvas window]
  (loop [sl (shuffle (range (* slotsx slotsy)))
         color (r/drand 0.0 1.0)
         i (first sl)
         p (idx-to-vec i)
        ]
    (let [ps (to-screenv p)
          sl' (filter #(not= i %) sl)
           z (* 0.7 (/ w slotsx))]
      (set-color canvas (grad color) )
      (ellipse canvas (.x ps) (.y ps) z z  )
      (when (pos? (count sl'))
        (let [[nc ni pp] (step p color sl')]
          (recur sl' nc ni pp)))))   
  canvas)




(defn draw-something
  ""
  [[canvas disp]]
  (with-canvas-> canvas
    (set-background 0 5 8)
    (set-color 35 35 35 16)
    (make-me disp)

  :done))



(defn example-01
  ""
  []
  (let [cnvs (canvas w h)
        window (show-window cnvs "beads" (/ w 2) (/ h 2) 30 nil   )]

    (defmethod key-pressed ["beads" \space] [_ _]
      (save cnvs (next-filename "results/beads/" ".jpg")))

    [cnvs window]))

(draw-something (example-01))

project.clj

(defproject gen-art "0.1.0-SNAPSHOT"
  :description "FIXME: write description"
  :url "http://example.com/FIXME"
  :license {:name "EPL-2.0 OR GPL-2.0-or-later WITH Classpath-exception-2.0"
            :url "https://www.eclipse.org/legal/epl-2.0/"}
  :dependencies [[org.clojure/clojure "1.10.0"]
                 [clojure2d "1.2.0-SNAPSHOT"]]
  :main ^:skip-aot gen-art.core
  :target-path "target/%s"
  :profiles {:uberjar {:aot :all}})