From 486890c7509e3c033355764a5680bf0e875ee988 Mon Sep 17 00:00:00 2001
From: Elmom <elmo.mantynen@iki.fi>
Date: Mon, 26 Jul 2010 13:13:31 +0300
Subject: [PATCH] Added utilities.scad from http://github.com/zzorn/FunRap

---
 README         |  1 +
 utilities.scad | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)
 create mode 100644 utilities.scad

diff --git a/README b/README
index c9aafec..396b898 100644
--- a/README
+++ b/README
@@ -29,5 +29,6 @@ Utils:
 * constants.scad: mathematical constants
 * curves.scad: mathematical functions defining curves
 * units.scad: easy metric units
+* utilities: geometric funtions and misc. useful stuff
 
 You are welcome to fork this project in github and request pulls. I will try to accomodate the community as much as possible in this.
diff --git a/utilities.scad b/utilities.scad
new file mode 100644
index 0000000..fe85c31
--- /dev/null
+++ b/utilities.scad
@@ -0,0 +1,58 @@
+/*
+ * Utility functions.
+ * 
+ * Originally by Hans Häggström, 2010.
+ * Dual licenced under Creative Commons Attribution-Share Alike 3.0 and LGPL2 or later
+ */
+
+<units.scad>
+
+function distance(a, b) = sqrt( (a[0] - b[0])*(a[0] - b[0]) + 
+                                (a[1] - b[1])*(a[1] - b[1]) + 
+                                (a[2] - b[2])*(a[2] - b[2]) );
+
+function length2(a) = sqrt( a[0]*a[0] + a[1]*a[1] );
+
+function normalized(a) = a / (max(distance([0,0,0], a), 0.00001));
+
+
+
+function angleOfNormalizedVector(n) = [0, -atan2(n[2], length2([n[0], n[1]])), atan2(n[1], n[0]) ];
+
+function angle(v) = angleOfNormalizedVector(normalized(v));
+
+function angleBetweenTwoPoints(a, b) = angle(normalized(b-a));
+
+
+CENTER = 0;
+LEFT = -0.5;
+RIGHT = 0.5;
+TOP = 0.5;
+BOTTOM = -0.5;
+
+FlatCap =0;
+ExtendedCap =0.5;
+CutCap =-0.5;
+
+
+module fromTo(from=[0,0,0], to=[1*m,0,0], size=[1*cm, 1*cm], align=[CENTER, CENTER], material=[0.5, 0.5, 0.5], name="", endExtras=[0,0], endCaps=[FlatCap, FlatCap], rotation=[0,0,0], printString=true) {
+
+  angle = angleBetweenTwoPoints(from, to);
+  length = distance(from, to) + endCaps[0]*size[0] + endCaps[1]*size[0] + endExtras[0] + endExtras[1];
+
+  if (length > 0) {
+    if (printString) echo(str("  " ,name, " ", size[0], "mm x ", size[1], "mm, length ",length,"mm"));
+
+    color(material)
+      translate(from)
+        rotate(angle) 
+          translate( [ -endCaps[0]*size[0] - endExtras[0], size[0]*(-0.5-align[0]), size[1]*(-0.5+align[1]) ] )
+            rotate(rotation) 
+              scale([length, size[0], size[1]]) child();
+  }
+}
+
+module part(name) {
+  echo("");
+  echo(str(name, ":"));
+}