Added 3D Vector Cross Product Function

src/math/Makefile.am

@@ -18,6 +18,7 @@ libpal_math_la_SOURCES = \
     p_cbrt.c \
     p_cos.c \
     p_cosh.c \
+    p_cross.c \
     p_div.c \
     p_dot.c \
     p_exp.c p_exp.h \
@@ -53,5 +54,3 @@ libpal_math_la_SOURCES = \
     tinymt/tinymt32.h
 
 libpal_math_la_LIBADD = -lm
-
-

src/math/p_cross.c

@@ -0,0 +1,34 @@
+#include <pal.h>
+
+/**
+ *
+ * Calculates the cross product between vectors 'a' and 'b', producing
+ * another vector result 'c'.
+ *
+ * @param a     Pointer to input 3d vector
+ *
+ * @param b     Pointer to input 3d vector
+ *
+ * @param c     Pointer to output 3d vector
+ *
+ * @param mag	Pointer to output magnitude scalar (set null to not compute)
+ *
+ * @return      None
+ *
+ */
+void p_cross_f32(const float *a, const float *b, float *c, float *mag)
+{
+    float tmp;
+
+    c[0] = a[1]*b[2] - a[2]*b[1];
+
+    c[1] = a[2]*b[0] - a[0]*b[2];
+
+    c[2] = a[0]*b[1] - a[1]*b[0];
+
+    if(mag)
+    {
+        tmp = c[0]*c[0] + c[1]*c[1] + c[2]*c[2];
+        p_sqrt_f32(&tmp, mag, 1);
+    }
+}