squared distance for vec3

docs/source/vec3.rst

@@ -56,6 +56,7 @@ Functions:
 #. :c:func:`glm_vec_inv_to`
 #. :c:func:`glm_vec_normalize`
 #. :c:func:`glm_vec_normalize_to`
+#. :c:func:`glm_vec_distance2`
 #. :c:func:`glm_vec_distance`
 #. :c:func:`glm_vec_angle`
 #. :c:func:`glm_vec_rotate`
@@ -366,6 +367,17 @@ Functions documentation
       | *[in]*  **v2**    vector2
       | *[out]* **dest**  center point
 
+.. c:function:: float  glm_vec_distance2(vec3 v1, vec3 v2)
+
+    squared distance between two vectors
+
+    Parameters:
+      | *[in]*  **mat**   vector1
+      | *[in]*  **row1**  vector2
+
+    Returns:
+      | squared distance (distance * distance)
+
 .. c:function:: float  glm_vec_distance(vec3 v1, vec3 v2)
 
     distance between two vectors

include/cglm/call/vec3.h

@@ -148,6 +148,10 @@ CGLM_EXPORT
 void
 glmc_vec_center(vec3 v1, vec3 v2, vec3 dest);
 
+CGLM_EXPORT
+float
+glmc_vec_distance2(vec3 v1, vec3 v2);
+
 CGLM_EXPORT
 float
 glmc_vec_distance(vec3 v1, vec3 v2);

include/cglm/vec3.h

@@ -633,6 +633,21 @@ glm_vec_center(vec3 v1, vec3 v2, vec3 dest) {
   glm_vec_scale(dest, 0.5f, dest);
 }
 
+/**
+ * @brief squared distance between two vectors
+ *
+ * @param[in] v1 vector1
+ * @param[in] v2 vector2
+ * @return returns squared distance (distance * distance)
+ */
+CGLM_INLINE
+float
+glm_vec_distance2(vec3 v1, vec3 v2) {
+  return glm_pow2(v2[0] - v1[0])
+       + glm_pow2(v2[1] - v1[1])
+       + glm_pow2(v2[2] - v1[2]);
+}
+
 /**
  * @brief distance between two vectors
  *
@@ -643,9 +658,7 @@ glm_vec_center(vec3 v1, vec3 v2, vec3 dest) {
 CGLM_INLINE
 float
 glm_vec_distance(vec3 v1, vec3 v2) {
-  return sqrtf(glm_pow2(v2[0] - v1[0])
+  return sqrtf(glm_vec_distance2(v1, v2));
-             + glm_pow2(v2[1] - v1[1])
-             + glm_pow2(v2[2] - v1[2]));
 }
 
 /*!

src/vec3.c

@@ -206,6 +206,12 @@ glmc_vec_center(vec3 v1, vec3 v2, vec3 dest) {
   glm_vec_center(v1, v2, dest);
 }
 
+CGLM_EXPORT
+float
+glmc_vec_distance2(vec3 v1, vec3 v2) {
+  return glm_vec_distance2(v1, v2);
+}
+
 CGLM_EXPORT
 float
 glmc_vec_distance(vec3 v1, vec3 v2) {