Add differential-harmonics sketch

src/shimmers/sketches.cljs

@@ -65,6 +65,7 @@
    shimmers.sketches.delaunay-voronoi
    shimmers.sketches.dependents
    shimmers.sketches.differential-growth
+   shimmers.sketches.differential-harmonics
    shimmers.sketches.disassociated-boxes
    shimmers.sketches.dispersion
    shimmers.sketches.displacements-inbetween

src/shimmers/sketches/differential_harmonics.cljs

@@ -0,0 +1,82 @@
+(ns shimmers.sketches.differential-harmonics
+  (:require
+   [shimmers.common.svg :as csvg :include-macros true]
+   [shimmers.common.ui.controls :as ctrl]
+   [shimmers.common.ui.debug :as debug]
+   [shimmers.math.deterministic-random :as dr]
+   [shimmers.math.wobble :as mw :refer [O R]]
+   [shimmers.model.harmonics :as harm]
+   [shimmers.sketch :as sketch :include-macros true]
+   [shimmers.view.sketch :as view-sketch]
+   [thi.ng.geom.circle :as gc]
+   [thi.ng.geom.line :as gl]
+   [thi.ng.geom.vector :as gv]
+   [thi.ng.math.core :as tm]))
+
+(def width 800)
+(def height 600)
+(defn rv [x y]
+  (gv/vec2 (* width x) (* height y)))
+
+(defn plot
+  [center radius {[a b c] :freqs [a-osc b-osc c-osc] :freqs-osc} s]
+  (-> (gv/vec2)
+      (tm/+ (R a (* 0.2 (O a-osc 0 s)) 0.65 s))
+      (tm/+ (R b (* 0.6 (O b-osc 0 (- 1.0 s))) 0.30 s))
+      (tm/+ (R c (* 0.8 (O c-osc 0 s)) 0.05 s))
+      (tm/* radius)
+      (tm/+ center)))
+
+(defn perturb [params v]
+  (-> params
+      (update-in [:freqs 0] + (* 0.6 v))
+      (update-in [:freqs 1] + (* 0.25 v))
+      (update-in [:freqs 2] + (* -0.15 v))))
+
+(defn shapes [{:keys [n-points d-freq] :as params}]
+  (let [center (rv 0.5 0.5)
+        radius (* 0.48 height)
+        r (* 0.0033 height)]
+    (for [s (tm/norm-range n-points)]
+      (let [d1 (* 0.04 (O d-freq 0 s))
+            d2 (* 0.04 (O d-freq tm/QUARTER_PI s))
+            p (plot center radius (perturb params (- d1)) s)
+            q (plot center radius (perturb params d2) s)]
+        (csvg/group {}
+          (gc/circle p r)
+          (gc/circle q r)
+          (gl/line2 p q))))))
+
+(defn scene [params]
+  (csvg/svg-timed {:width width
+                   :height height
+                   :stroke "black"
+                   :fill "white"
+                   :stroke-width 0.5}
+    (shapes params)))
+
+(defn parameters []
+  (let [[a b c] (harm/abc)]
+    {:n-points 2048
+     :freqs [a b c]
+     :freqs-osc [(* (dr/random-sign) (dr/random-int 5))
+                 (* (dr/random-sign) (dr/random-int 7))
+                 (* (dr/random-sign) (dr/random-int 13))]
+     :d-freq (dr/random-int 1 7)}))
+
+(defn page []
+  (let [params (parameters)]
+    (fn []
+      [sketch/with-explanation
+       [:div.canvas-frame [scene params]]
+       [:div.flexcols
+        [view-sketch/generate :differential-harmonics]
+        [:p "Similar to helix but instead perturb oscillation frequency forward and backward from base harmonic."]]
+       [:div.readable-width
+        (debug/pre-edn params)]])))
+
+(sketch/definition differential-harmonics
+    {:created-at "2024-05-16"
+     :tags #{}
+     :type :svg}
+  (ctrl/mount page))