add snapping points of selection bounds and refactor

Author: sprocketc

.clj-kondo/metosin/malli-types-cljs/config.edn

@@ -9,7 +9,8 @@
    [renderer.element.handlers :as element.h]
    [renderer.snap.db :refer [SnapOption NearestNeighbor]]
    [renderer.snap.subs :as-alias snap.s]
-   [renderer.utils.element :as utils.el]
+   [renderer.utils.bounds :as bounds]
+   [renderer.utils.element :as element]
    [renderer.utils.math :refer [Vec2D]]))
 
 (m/=> toggle-option [:-> App SnapOption App])
@@ -23,13 +24,17 @@
 (defn base-points
   [db]
   (let [elements (vals (element.h/entities db))
-        selected-visible (filter #(and (:visible %) (:selected %)) elements)]
+        selected (filter :selected elements)
+        selected-visible (filter :visible selected)
+        options (-> db :snap :options)]
     (when (-> db :snap :active)
       (cond
-        (and (contains? #{:translate :clone} (:state db)) (seq selected-visible))
-        (reduce (fn [points element]
-                  (apply conj points (utils.el/snapping-points element (-> db :snap :options))))
-                [] selected-visible)
+        (and (contains? #{:translate :clone} (:state db)) (seq selected))
+        (reduce (fn [points el] (into points (element/snapping-points el options)))
+                (if (seq (rest selected))
+                  (bounds/->snapping-points (element.h/bounds db) options)
+                  [])
+                selected-visible)
 
         (contains? #{:edit :scale} (:state db))
         [(mat/add [(-> db :clicked-element :x) (-> db :clicked-element :y)]

src/renderer/snap/handlers.cljs

@@ -32,8 +32,7 @@
  :<- [::options]
  (fn [[non-selected-visible-elements active options] _]
    (when active
-     (reduce (fn [points element]
-               (apply conj points (utils.el/snapping-points element options)))
+     (reduce (fn [points el] (into points (utils.el/snapping-points el options)))
              [] non-selected-visible-elements))))
 
 (rf/reg-sub

src/renderer/snap/subs.cljs

@@ -2,6 +2,7 @@
   (:require
    [clojure.core.matrix :as mat]
    [malli.core :as m]
+   [renderer.snap.db :refer [SnapOptions]]
    [renderer.utils.dom :refer [DomElement]]
    [renderer.utils.math :refer [Vec2D]]))
 
@@ -73,3 +74,24 @@
        (<= top y)
        (>= right x)
        (>= bottom y)))
+
+(m/=> ->snapping-points [:-> Bounds SnapOptions [:* Vec2D]])
+(defn ->snapping-points
+  [bounds options]
+  (let [[x1 y1 x2 y2] bounds
+        [cx cy] (center bounds)]
+    (cond-> []
+      (:corners options)
+      (into [[x1 y1]
+             [x1 y2]
+             [x2 y1]
+             [x2 y2]])
+
+      (:centers options)
+      (into [[cx cy]])
+
+      (:midpoints options)
+      (into [[x1 cy]
+             [x2 cy]
+             [cx y1]
+             [cx y2]]))))

src/renderer/utils/bounds.cljs

@@ -57,25 +57,9 @@
 (defn snapping-points
   [el options]
   (let [points (or (element.hierarchy/snapping-points el) [])]
-    (if-let [bounds (:bounds el)]
-      (let [[x1 y1 x2 y2] bounds
-            [cx cy] (utils.bounds/center bounds)]
-        (cond-> points
-          (:corners options)
-          (into [[x1 y1]
-                 [x1 y2]
-                 [x2 y1]
-                 [x2 y2]])
-
-          (:centers options)
-          (into [[cx cy]])
-
-          (:midpoints options)
-          (into [[x1 cy]
-                 [x2 cy]
-                 [cx y1]
-                 [cx y2]])))
-      points)))
+    (cond-> points
+      (:bounds el)
+      (into (utils.bounds/->snapping-points (:bounds el) options)))))
 
 (m/=> attributes [:-> Element Attrs])
 (defn attributes

src/renderer/utils/element.cljs

@@ -36,3 +36,10 @@
 (deftest test-center
   (testing "center of bounds"
     (is (= (bounds/center [0 0 10 10]) [5 5]))))
+
+(deftest test-->snapping-points
+  (testing "snapping points of bounds"
+    (is (= (bounds/->snapping-points [0 0 10 10] #{:corners :centers :midpoints})
+           [[0 0] [0 10] [10 0] [10 10] [5 5] [0 5] [10 5] [5 0] [5 10]]))
+
+    (is (= (bounds/->snapping-points [0 0 10 10] #{}) []))))