-// Given a point p, and a line through p0 with direction vector d,
-// find the shortest distance (squared) from the point to the line
-double sgPointLineDistSquared( const sgVec3 p, const sgVec3 p0,
- const sgVec3 d );
-
-// Given a point p, and a line through p0 with direction vector d,
-// find the shortest distance (squared) from the point to the line
-double sgdPointLineDistSquared( const sgdVec3 p, const sgdVec3 p0,
- const sgdVec3 d );
-
-// This is same as
-// sgMakeMatTrans4( sgMat4 sgTrans, sgVec3 trans )
-// sgPostMultMat4( sgMat, sgTRANS );
+/**
+ * Given a point p, and a line through p0 with direction vector d,
+ * find the closest point (p1) on the line (float version).
+ * @param p1 (out) closest point to p on the line
+ * @param p (in) original point
+ * @param p0 (in) point on the line
+ * @param d (in) vector defining line direction
+ */
+void sgClosestPointToLine( sgVec3 p1, const sgVec3 p, const sgVec3 p0,
+ const sgVec3 d );
+
+/**
+ * Given a point p, and a line through p0 with direction vector d,
+ * find the closest point (p1) on the line (double version).
+ * @param p1 (out) closest point to p on the line
+ * @param p (in) original point
+ * @param p0 (in) point on the line
+ * @param d (in) vector defining line direction
+ */
+void sgdClosestPointToLine( sgdVec3 p1, const sgdVec3 p, const sgdVec3 p0,
+ const sgdVec3 d );
+
+/**
+ * Given a point p, and a line through p0 with direction vector d,
+ * find the shortest distance (squared) from the point to the line (float
+ * version.)
+ * @param p (in) original point
+ * @param p0 (in) point on the line
+ * @param d (in) vector defining line direction
+ * @return shortest distance (squared) from p to line
+ */
+double sgClosestPointToLineDistSquared( const sgVec3 p, const sgVec3 p0,
+ const sgVec3 d );
+
+/**
+ * Given a point p, and a line through p0 with direction vector d,
+ * find the shortest distance (squared) from the point to the line (double
+ * version.)
+ * @param p (in) original point
+ * @param p0 (in) point on the line
+ * @param d (in) vector defining line direction
+ * @return shortest distance (squared) from p to line
+ */
+double sgdClosestPointToLineDistSquared( const sgdVec3 p, const sgdVec3 p0,
+ const sgdVec3 d );
+
+/**
+ * This is same as:
+ *
+ * <li> sgMakeMatTrans4( sgMat4 sgTrans, sgVec3 trans )
+ * <li> sgPostMultMat4( sgMat4 src, sgTRANS );
+ *
+ * @param src starting sgMat4 matrix
+ * @param trans translation vector
+ */