vectors: most things work

app/Main.hs

@@ -158,6 +158,7 @@ preludeModules carpDir = map (\s -> carpDir ++ "/core/" ++ s ++ ".carp") [ "Macr
                                                                          , "System"
                                                                          , "Test"
                                                                          , "Vector"
+                                                                         , "Geometry"
                                                                          ]
 
 main :: IO ()

core/Double.carp

@@ -10,8 +10,16 @@
   (register from-int (Fn [Int] Double))
   (register sin (Fn [Double] Double))
   (register cos (Fn [Double] Double))
+  (register acos (Fn [Double] Double))
   (register atan2 (Fn [Double Double] Double))
   (register sqrt (Fn [Double] Double))
   (register str (Fn [Double] String))
   (register copy (Fn [(Ref Double)] Double))
+
+  (defn clamp [min, max, val]
+    (if (> val max)
+      max
+      (if (< val min)
+        min
+        val)))
   )

core/Vector.carp

@@ -1,6 +1,5 @@
 ; missing: lerp
 
-
 (defdynamic append-multi- [strs]
   (if (= (count strs) 0)
     '@""
@@ -9,6 +8,11 @@
 (defmacro append-multi [:rest strs]
   (append-multi- strs))
 
+(defn doubleq [a, b]
+  (if (Double.> a b)
+    (Double.< (Double.- a b) 0.00001)
+    (Double.< (Double.- b a) 0.00001)))
+
 (defmodule Vector2
   (deftype V [x Double, y Double])
 
@@ -34,11 +38,6 @@
     (V.init (Double./ (V.x a) n)
             (Double./ (V.y a) n)))
 
-  (defn doubleq [a, b]
-    (if (Double.> a b)
-      (Double.< (Double.- a b) 0.00001)
-      (Double.< (Double.- b a) 0.00001)))
-
   (defn = [a, b]
     (and (doubleq (V.x a) (V.x b))
          (doubleq (V.y a) (V.y b))))
@@ -73,9 +72,9 @@
     (Double.+ (Double.* (V.x x) (V.x y))
               (Double.* (V.y x) (V.y y))))
 
-  ;(defn angle-between [a b]
-  ;  (let [dmm (Double./ (dot a b) (Double.* (mag a) (mag b)))]
-  ;    (Double.acos (Double.clamp -1.0 1.0 dmm))))
+  (defn angle-between [a b]
+    (let [dmm (Double./ (dot a b) (Double.* (mag a) (mag b)))]
+      (Double.acos (Double.clamp -1.0 1.0 dmm))))
 )
 
 (defmodule Vector3
@@ -113,14 +112,14 @@
           z (V.z o)]
       (Double.+ (Double.* x x) (Double.+ (Double.* y y) (Double.* z z)))))
 
-  ;(defn mag [o]
-  ;  (Double.sqrt (mag-sq o)))
+  (defn mag [o]
+    (Double.sqrt (mag-sq o)))
 
-  ;(defn normalize [o]
-  ;  (let [m (mag o)]
-  ;    (if (= m 0)
-  ;      o
-  ;      (div o n))))
+  (defn normalize [o]
+    (let [m (mag o)]
+      (if (doubleq m 0.0)
+        (V.copy o)
+        (/ o m))))
 
   (defn cross [x, y]
     (V.init
@@ -136,9 +135,9 @@
               (Double.+ (Double.* (V.y x) (V.y y))
                         (Double.* (V.z x) (V.z y)))))
 
-  ;(defn angle-between [a b]
-  ;  (let [dmm (Double./ (dot a b) (Double.* (mag a) (mag b)))]
-  ;    (Double.acos (Double.clamp -1.0 1.0 dmm))))
+  (defn angle-between [a b]
+    (let [dmm (Double./ (dot a b) (Double.* (mag a) (mag b)))]
+      (Double.acos (Double.clamp -1.0 1.0 dmm))))
 )
 
 ;(defmodule VectorN

core/geometry.carp

@@ -0,0 +1,6 @@
+(defmodule Geometry
+  (defn degree-to-radians [n]
+    (Double./ (Double.* 2.0 (Double.* n Double.π)) 360.0))
+
+  (defn radians-to-degree [n]
+    (Double./ (Double.* 360.0 n) (Double.* 2.0 Double.π))))

core/prelude.h

@@ -209,6 +209,10 @@ double Double_sqrt(double x) {
     return sqrt(x);
 }
 
+double Double_acos(double x) {
+    return acos(x);
+}
+
 double Double_atan2(double x, double y) {
     return atan2(x, y);
 }

examples/vector.carp

@@ -1,5 +1,6 @@
 (use IO)
 (use Vector2)
+(use Geometry)
 
 (defn main []
   (let [x (Vector2.init 1.0 2.0)
@@ -9,4 +10,5 @@
       (println &(Vector2.str &x))
       (println &(Vector2.str &y))
       (println &(Double.str (Vector2.mag &y)))
-      (println &(Vector2.str &(Vector2.rotate &x (Double./ Double.π 2.0)))))))
+      (println &(Vector2.str &(Vector2.rotate &x (Geometry.degree-to-radians 90.0))))
+      (println &(Double.str (Geometry.radians-to-degree (Vector2.angle-between &x &y)))))))