add some examples testing various hatching examples for rectangles

src/shimmers/sketches.cljs

@@ -119,6 +119,7 @@
    shimmers.sketches.harsh-lines
    shimmers.sketches.harmonograph
    shimmers.sketches.hatched-rectangles
+   shimmers.sketches.hatch-test
    shimmers.sketches.helix
    shimmers.sketches.hexaclock
    shimmers.sketches.hexaflexagon

src/shimmers/sketches/hatch_test.cljs

@@ -0,0 +1,83 @@
+(ns shimmers.sketches.hatch-test
+  (:require
+   [shimmers.algorithm.line-clipping :as clip]
+   [shimmers.common.svg :as csvg :include-macros true]
+   [shimmers.common.ui.controls :as ctrl]
+   [shimmers.common.ui.svg :as usvg]
+   [shimmers.math.deterministic-random :as dr]
+   [shimmers.sketch :as sketch :include-macros true]
+   [thi.ng.geom.core :as g]
+   [thi.ng.geom.rect :as rect]
+   [thi.ng.geom.vector :as gv]
+   [shimmers.math.geometry :as geometry]
+   [shimmers.math.equations :as eq]))
+
+(def width 800)
+(def height 800)
+(defn rv [x y]
+  (gv/vec2 (* width x) (* height y)))
+
+(defn examples []
+  [(fn [{[w _] :size :as cell}]
+     (let [rect (-> (rect/rect (/ w 2))
+                    (g/center (g/centroid cell)))]
+       (into [rect]
+             (clip/hatch-rectangle rect (dr/random 4 12) (dr/random-tau)
+                                   [(dr/random) (dr/random)]))))
+   (fn [{[w _] :size :as cell}]
+     (let [rect (-> (rect/rect (/ w 2))
+                    (g/center (g/centroid cell)))
+           theta (dr/random-tau)]
+       (into [(geometry/rotate-around-centroid rect theta)]
+             (mapv (fn [line] (geometry/rotate-around line (g/centroid rect) theta))
+                   (clip/hatch-rectangle rect (dr/random 4 12) (dr/random-tau)
+                                         [(dr/random) (dr/random)])))))
+   (fn [{[w _] :size :as cell}]
+     (let [rect (-> (rect/rect (/ w 2))
+                    (g/center (g/centroid cell)))
+           spacing (dr/random 4 16)
+           theta (dr/random-tau)
+           theta0 (dr/random-tau)
+           theta1 (+ theta0 (dr/gaussian (* eq/TAU 0.25) 0.1))]
+       (concat [(geometry/rotate-around-centroid rect theta)]
+               (mapv (fn [line] (geometry/rotate-around line (g/centroid rect) theta))
+                     (clip/hatch-rectangle rect spacing theta0
+                                           [(dr/random) (dr/random)]))
+               (mapv (fn [line] (geometry/rotate-around line (g/centroid rect) theta))
+                     (clip/hatch-rectangle rect spacing theta1
+                                           [(dr/random) (dr/random)])))))
+
+   (fn [{[w _] :size :as cell}]
+     (let [rect (-> (rect/rect (/ w 2))
+                    (g/center (g/centroid cell)))
+           theta (dr/random-tau)
+           theta0 (dr/random-tau)]
+       (concat [(geometry/rotate-around-centroid rect theta)]
+               (mapv (fn [line] (geometry/rotate-around line (g/centroid rect) theta))
+                     (clip/hatch-rectangle rect (dr/random 4 12) theta0
+                                           [(dr/random) (dr/random)]))
+               (mapv (fn [line] (geometry/rotate-around line (g/centroid rect) theta))
+                     (clip/hatch-rectangle rect (dr/random 4 12) theta0
+                                           [(dr/random) (dr/random)])))))])
+
+(defn shapes [bounds examples]
+  (for [[cell example] (map vector (g/subdivide bounds {:num 2})
+                            examples)]
+    (csvg/group {}
+      (example cell))))
+
+(defn scene [{:keys [scene-id]}]
+  (csvg/svg-timed {:id scene-id
+                   :width width
+                   :height height
+                   :stroke "black"
+                   :fill "white"
+                   :stroke-width 0.5}
+    (shapes (csvg/screen width height)
+            (examples))))
+
+(sketch/definition hatch-test
+  {:created-at "2025-01-22"
+   :tags #{}
+   :type :svg}
+  (ctrl/mount (usvg/page sketch-args scene)))