draw triangles or squares depending on another noise field

src/shimmers/sketches/blustery_day.cljs

@@ -5,10 +5,12 @@
    [shimmers.common.ui.svg :as usvg]
    [shimmers.math.deterministic-random :as dr]
    [shimmers.math.equations :as eq]
+   [shimmers.math.geometry.triangle :as triangle]
    [shimmers.math.vector :as v]
    [shimmers.sketch :as sketch :include-macros true]
    [thi.ng.geom.circle :as gc]
    [thi.ng.geom.core :as g]
+   [thi.ng.geom.rect :as rect]
    [thi.ng.geom.vector :as gv]
    [thi.ng.math.core :as tm]))
 
@@ -21,17 +23,27 @@
   (for [cell (g/subdivide bounds {:cols (/ width 5)
                                   :rows (/ height 5)})
         :let [p (g/centroid cell)
-              [x y] p
               dir-noise (dr/noise-at-point-01 seed 0.0025 p)
               amp-noise (dr/noise-at-point-01 seed 0.0025 (tm/+ p (:size bounds)))
               size-noise (dr/noise-at-point-01 seed 0.0025 (tm/+ p (tm/* (:size bounds) 2)))
-              jitter-noise (dr/noise-at-point-01 seed 0.0025 (tm/+ p (tm/* (:size bounds) 3)))]
+              jitter-noise (dr/noise-at-point-01 seed 0.0025 (tm/+ p (tm/* (:size bounds) 3)))
+              shape-noise (dr/noise-at-point-01 seed 0.0025 (tm/+ p (tm/* (:size bounds) 4)))
+              angle (* 1.5 eq/TAU dir-noise)]
         :when (< (dr/gaussian 0.0 (tm/smoothstep* 0.5 1.0 jitter-noise)) 1.0)]
-    (gc/circle (-> p
-                   (v/+polar (* 32.0 amp-noise) (* 1.5 eq/TAU dir-noise))
-                   (v/+polar (* 0.75 (dr/gaussian 0.0 (tm/smoothstep* 0.5 1.0 jitter-noise)))
-                             (dr/random-tau)))
-               (+ 0.5 (* 2.0 size-noise)))))
+    (let [c (gc/circle (-> p
+                           (v/+polar (* 32.0 amp-noise) angle)
+                           (v/+polar (* 0.75 (dr/gaussian 0.0 (tm/smoothstep* 0.5 1.0 jitter-noise)))
+                                     (dr/random-tau)))
+                       (+ 0.5 (* 2.0 size-noise)))]
+      (cond (< shape-noise 0.2)
+            (-> (* 1.1 (:r c))
+                rect/rect
+                g/center
+                (g/rotate angle)
+                (g/translate (:p c)))
+            (> shape-noise 0.8)
+            (triangle/inscribed-equilateral (:p c) (* 1.1 (:r c)) angle)
+            :else c))))
 
 (defn scene [{:keys [scene-id]}]
   (csvg/svg-timed {:id scene-id