Unify rotate-x/y/z into single rotate function with axis keyword

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: leifericf

src/eido/math.clj

@@ -61,32 +61,21 @@
 
 ;; --- rotations ---
 
-(defn rotate-x
-  "Rotates a point around the X axis by angle (radians)."
-  [[x y z] angle]
+(defn rotate
+  "Rotates a point around the given axis (:x, :y, or :z) by angle (radians)."
+  [[x y z] axis angle]
   (let [c (Math/cos angle)
         s (Math/sin angle)]
-    [(double x)
-     (- (* (double y) c) (* (double z) s))
-     (+ (* (double y) s) (* (double z) c))]))
-
-(defn rotate-y
-  "Rotates a point around the Y axis by angle (radians)."
-  [[x y z] angle]
-  (let [c (Math/cos angle)
-        s (Math/sin angle)]
-    [(+ (* (double x) c) (* (double z) s))
-     (double y)
-     (- (* (double z) c) (* (double x) s))]))
-
-(defn rotate-z
-  "Rotates a point around the Z axis by angle (radians)."
-  [[x y z] angle]
-  (let [c (Math/cos angle)
-        s (Math/sin angle)]
-    [(- (* (double x) c) (* (double y) s))
-     (+ (* (double x) s) (* (double y) c))
-     (double z)]))
+    (case axis
+      :x [(double x)
+          (- (* (double y) c) (* (double z) s))
+          (+ (* (double y) s) (* (double z) c))]
+      :y [(+ (* (double x) c) (* (double z) s))
+          (double y)
+          (- (* (double z) c) (* (double x) s))]
+      :z [(- (* (double x) c) (* (double y) s))
+          (+ (* (double x) s) (* (double y) c))
+          (double z)])))
 
 ;; --- projection ---
 
@@ -122,9 +111,9 @@
         pitch (get projection :projection/pitch 0.0)
         roll  (get projection :projection/roll 0.0)]
     (-> point
-        (rotate-y (- yaw))
-        (rotate-x (- pitch))
-        (rotate-z (- roll)))))
+        (rotate :y (- yaw))
+        (rotate :x (- pitch))
+        (rotate :z (- roll)))))
 
 (defn make-projector
   "Returns a function that projects 3D points to 2D screen coordinates.

src/eido/scene3d/transform.clj

@@ -16,27 +16,20 @@
             (assoc face :face/vertices new-verts)))
         mesh))
 
-(defn- rotate-fn [axis]
-  (case axis
-    :x m/rotate-x
-    :y m/rotate-y
-    :z m/rotate-z))
-
 (defn rotate-mesh
   "Rotates all vertices and normals in a mesh around the given axis.
   axis: :x, :y, or :z. angle: radians."
   [mesh axis angle]
-  (let [rot (rotate-fn axis)]
-    (mapv (fn [face]
-            (let [new-verts  (mapv #(rot % angle) (:face/vertices face))
-                  new-normal (rot (:face/normal face) angle)]
-              (cond-> (assoc face
-                        :face/vertices new-verts
-                        :face/normal new-normal)
-                (:face/vertex-normals face)
-                (assoc :face/vertex-normals
-                  (mapv #(rot % angle) (:face/vertex-normals face))))))
-          mesh)))
+  (mapv (fn [face]
+          (let [new-verts  (mapv #(m/rotate % axis angle) (:face/vertices face))
+                new-normal (m/rotate (:face/normal face) axis angle)]
+            (cond-> (assoc face
+                      :face/vertices new-verts
+                      :face/normal new-normal)
+              (:face/vertex-normals face)
+              (assoc :face/vertex-normals
+                (mapv #(m/rotate % axis angle) (:face/vertex-normals face))))))
+        mesh))
 
 (defn scale-mesh
   "Scales all vertices in a mesh. factor is a number (uniform) or [sx sy sz]."
@@ -70,9 +63,8 @@
   (let [pos (u/axis-component axis vertex)
         range (- (double ax-max) (double ax-min))
         t (if (zero? range) 0.0 (/ (- pos (double ax-min)) range))
-        angle (* (double amount) t)
-        rot (case axis :x m/rotate-x :y m/rotate-y :z m/rotate-z)]
-    (rot vertex angle)))
+        angle (* (double amount) t)]
+    (m/rotate vertex axis angle)))
 
 (defn- deform-taper
   "Scales the cross-section perpendicular to axis by position along it."
@@ -95,8 +87,8 @@
         t (if (zero? range) 0.0 (/ (- pos (double ax-min)) range))
         angle (* (double amount) t)
         ;; Bend around perpendicular axis: Y bends around Z, X around Y, Z around X
-        rot (case axis :x m/rotate-y :y m/rotate-z :z m/rotate-x)]
-    (rot vertex angle)))
+        bend-axis (case axis :x :y :y :z :z :x)]
+    (m/rotate vertex bend-axis angle)))
 
 (defn- deform-inflate
   "Pushes each vertex along its face normal by a fixed amount."

test/eido/math_test.clj

@@ -50,26 +50,22 @@
 
 ;; --- rotations ---
 
-(deftest rotate-x-test
-  (testing "90 degrees rotates Y to Z"
-    (let [result (m/rotate-x [0 1 0] (/ Math/PI 2))]
+(deftest rotate-test
+  (testing "X: 90 degrees rotates Y to Z"
+    (let [result (m/rotate [0 1 0] :x (/ Math/PI 2))]
       (is (approx= [0.0 0.0 1.0] result))))
-  (testing "identity rotation"
-    (is (approx= [1.0 2.0 3.0] (m/rotate-x [1 2 3] 0)))))
-
-(deftest rotate-y-test
-  (testing "90 degrees rotates Z to X"
-    (let [result (m/rotate-y [0 0 1] (/ Math/PI 2))]
+  (testing "X: identity rotation"
+    (is (approx= [1.0 2.0 3.0] (m/rotate [1 2 3] :x 0))))
+  (testing "Y: 90 degrees rotates Z to X"
+    (let [result (m/rotate [0 0 1] :y (/ Math/PI 2))]
       (is (approx= [1.0 0.0 0.0] result))))
-  (testing "identity rotation"
-    (is (approx= [1.0 2.0 3.0] (m/rotate-y [1 2 3] 0)))))
-
-(deftest rotate-z-test
-  (testing "90 degrees rotates X to Y"
-    (let [result (m/rotate-z [1 0 0] (/ Math/PI 2))]
+  (testing "Y: identity rotation"
+    (is (approx= [1.0 2.0 3.0] (m/rotate [1 2 3] :y 0))))
+  (testing "Z: 90 degrees rotates X to Y"
+    (let [result (m/rotate [1 0 0] :z (/ Math/PI 2))]
       (is (approx= [0.0 1.0 0.0] result))))
-  (testing "identity rotation"
-    (is (approx= [1.0 2.0 3.0] (m/rotate-z [1 2 3] 0)))))
+  (testing "Z: identity rotation"
+    (is (approx= [1.0 2.0 3.0] (m/rotate [1 2 3] :z 0)))))
 
 ;; --- projections ---