Added multiply.scad

multiply.scad

@@ -0,0 +1,29 @@
+/*
+ * Multiplication along certain curves
+ *
+ * Copyright by Elmo Mäntynen, 2012.
+ * Licenced under LGPL2 or later
+ */
+
+include <units.scad>
+
+use <utilities.scad>
+
+// TODO check that the axis parameter works as intended
+// Duplicate everything $no of times around an $axis, for $angle/360 rounds
+module spin(no, angle=360, axis=Z){
+    for (i = [1:no]){
+        rotate(normalized_axis(axis)*angle*no/i) union(){
+            for (i = [0 : $children-1]) child(i);
+        }
+    }
+}
+
+//Doesn't work currently
+module duplicate(axis=Z) spin(no=2, axis=axis) child(0);
+
+module linear_multiply(no, separation, axis=Z){
+    for (i = [0:no-1]){
+        translate(i*separation*axis) child(0);
+    }
+}

units.scad

@@ -10,8 +10,13 @@ mm = 1;
 cm = 10 * mm;
 dm = 100 * mm;
 m = 1000 * mm;
+
 inch = 25.4 * mm;
 
+X = [1, 0, 0];
+Y = [0, 1, 0];
+Z = [0, 0, 1];
+
 M3 = 3*mm;
 M4 = 4*mm;
 M5 = 5*mm;

utilities.scad

@@ -15,7 +15,9 @@ 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 normalized_axis(a) = a == "x" ? [1, 0, 0]:
+                   a == "y" ? [0, 1, 0]:
+                   a == "z" ? [0, 0, 1]: normalized(a);
 
 function angleOfNormalizedVector(n) = [0, -atan2(n[2], length2([n[0], n[1]])), atan2(n[1], n[0]) ];
 
@@ -23,16 +25,6 @@ function angle(v) = angleOfNormalizedVector(normalized(v));
 
 function angleBetweenTwoPoints(a, b) = angle(normalized(b-a));
 
-// TODO check that the axis parameter works as intended
-// Duplicate everything $no of times around an $axis, for $angle/360 rounds
-module spin(no, angle=360, axis=[0, 0, 1]){
-    for (i = [1:no]){
-        rotate(normalized(axis)*angle*no/i) union(){
-            for (i = [0 : $children-1]) child(i);
-        }
-    }
-}
- 
 
 CENTER = 0;
 LEFT = -0.5;