The simplest possible @thing_clj physics + @Quilist demo

core.cljs

(ns gumball-machine.core
  (:require [thi.ng.color.core :as col]
            [thi.ng.math.core :as m]
            [thi.ng.geom.core :as g]
            [thi.ng.geom.core.vector :refer [vec3]]
            [thi.ng.geom.physics.core :as ph]
            [thi.ng.geom.sphere :refer [sphere]]
            [quil.core :as q :include-macros true]))

(def particles
  (repeatedly 20 #(ph/particle (vec3 (m/random -50 50)
                                     (m/random -50 50)
                                     (m/random -50 50)) 1)))

(def engine (ph/physics {:particles particles
                         :drag 0.05
                         :constraints {:w (ph/shape-constraint-inside
                                           (g/center (sphere 200)))}
                         :behaviors {:g (ph/gravity (vec3 0 0.5 0))}}))

(defn setup []
  (q/smooth)
  (q/frame-rate 55)
  (q/color-mode :hsb)
  (q/no-stroke))

(defn draw []
  ;; tick the world clock, recalculate particle positions
  (ph/timestep engine 1)
  ;; if all the particles have come to rest...
  (when (every? #(< (second (ph/velocity %)) 0.08) particles)
    (doseq [p particles]
      ;; apply a randomized force to them
      (ph/add-force p (vec3 (m/random -10 10) -10 (m/random -10 10)))))

  ;; set up bg + lighting conditions
  (q/background 51)
  (q/ambient-light 0 0 80)
  (q/directional-light 0 0 150 0 0 -1)
  (q/light-specular 0 0 200)
  (q/specular 0 0 70)
  (q/shininess 0.5)
  
  ;; draw the particles
  (q/with-translation [(/ (q/width) 2) (/ (q/height) 2) 100]
    (doseq [[i p] (map-indexed vector particles)]
      (let [[x y z] (ph/position p)]
        (q/fill (* i 12) 255 255)
        (q/with-translation [x y z]
          (q/sphere 6))))))

(q/defsketch gumball-machine
  :host "gumball-machine"
  :size [600 600]
  :renderer :p3d
  :setup setup
  :draw draw)

project.clj

(defproject gumball-machine "0.1.0-SNAPSHOT"
  :description "Using thi.ng from quil + clojurescript."
  :dependencies [[org.clojure/clojure "1.7.0"]
                 [quil "2.3.0"]
                 [org.clojure/clojurescript "1.7.170"]
                 [thi.ng/geom "0.0.908"]
                 [thi.ng/color "1.0.0"]]

  :plugins [[lein-cljsbuild "1.1.1"]]
  :hooks [leiningen.cljsbuild]

  :cljsbuild {:builds [{:source-paths ["src"]
                        :compiler {:output-to "js/main.js"
                                   :output-dir "out"
                                   :main "gumball_machine.core"
                                   :optimizations :advanced
                                   :pretty-print false}}]})