From e635755528dc7642e9b166b95e2367942ed31dcd Mon Sep 17 00:00:00 2001
From: Revar Desmera <revarbat@gmail.com>
Date: Fri, 20 Mar 2020 22:15:41 -0700
Subject: [PATCH] Added vsqr(), vnf_centroid(), and vnf_volume()

---
 vectors.scad |  8 ++++++++
 version.scad |  2 +-
 vnf.scad     | 41 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/vectors.scad b/vectors.scad
index ed8a848..9509b6c 100644
--- a/vectors.scad
+++ b/vectors.scad
@@ -95,6 +95,14 @@ function vdiv(v1, v2) = [for (i = [0:1:len(v1)-1]) v1[i]/v2[i]];
 function vabs(v) = [for (x=v) abs(x)];
 
 
+// Function: vsqr()
+// Usage:
+//   x = vsqr(v);
+// Description:
+//   Returns a vector where each value in the original given vector is squared.
+function vsqr(v) = [for(i=v) i*i];
+
+
 // Function: unit()
 // Description:
 //   Returns unit length normalized version of vector v.
diff --git a/version.scad b/version.scad
index b1ce138..1ed74dc 100644
--- a/version.scad
+++ b/version.scad
@@ -8,7 +8,7 @@
 //////////////////////////////////////////////////////////////////////
 
 
-BOSL_VERSION = [2,0,208];
+BOSL_VERSION = [2,0,209];
 
 
 // Section: BOSL Library Version Functions
diff --git a/vnf.scad b/vnf.scad
index 568ec7d..e1ea665 100644
--- a/vnf.scad
+++ b/vnf.scad
@@ -336,6 +336,47 @@ module vnf_polyhedron(vnf, convexity=2) {
 }
 
 
+// Function: vnf_volume()
+// Usage:
+//   vol = vnf_volume(vnf);
+// Description:
+//   Returns the volume enclosed by the given manifold VNF.  May return a negative value if faces are reversed.
+function vnf_volume(vnf) =
+	let(vnf = vnf_triangulate(vnf))
+	sum([
+		for(face_index=vnf[1]) let(
+			face = select(vnf[0], face_index),
+			n = cross(face[2]-face[0],face[1]-face[0])
+		) face[0] * n
+	])/6;
+
+
+// Function: vnf_centroid()
+// Usage:
+//   vol = vnf_centroid(vnf);
+// Description:
+//   Returns the centroid of the given manifold VNF.
+function vnf_centroid(vnf) =
+	let(
+		vnf = vnf_triangulate(vnf),
+		val=sum([
+			for(face_index=vnf[1])
+			let(
+				face = select(vnf[0], face_index),
+				n = cross(face[2]-face[0],face[1]-face[0])
+			) [
+				face[0] * n,
+				vmul(n,
+					vsqr(face[0] + face[1]) +
+					vsqr(face[0] + face[2]) +
+					vsqr(face[1] + face[2])
+				)
+			]
+		])
+	) val[1]/val[0]/8;
+
+
+
 // Function&Module: vnf_validate()
 // Usage: As Function
 //   fails = vnf_validate(vnf);