math: vector: Add vmap.

* sly/math/vector.scm (vmap): New procedure.

1 files changed, 12 insertions, 1 deletions

diff --git a/sly/math/vector.scm b/sly/math/vector.scm
index 717c5f6..33c62d8 100644
--- a/sly/math/vector.scm
+++ b/sly/math/vector.scm
@@ -32,7 +32,7 @@
             vector2 vector3 vector4
             vector2? vector3? vector4?
             vx vy vz vw
-            v+ v- v* vdot vcross
+            vmap v+ v- v* vdot vcross
             magnitude normalize vlerp))
 
 (define-record-type <vector2>
@@ -78,6 +78,17 @@
 
 (define vw vector4-w)
 
+(define (vmap proc v)
+  "Return a new vector that is the result of applying PROC to each
+element of the 2D/3D/4D vector V."
+  (match v
+    (($ <vector2> x y)
+     (vector2 (proc x) (proc y)))
+    (($ <vector3> x y z)
+     (vector3 (proc x) (proc y) (proc z)))
+    (($ <vector4> x y z w)
+     (vector4 (proc x) (proc y) (proc z) (proc w)))))
+
 (define-syntax-rule (vector-lambda proc)
   (match-lambda*
    ((($ <vector2> x1 y1) ($ <vector2> x2 y2))