MCAD-Library/utilities.scad

/*
 * Utility functions.
 *
 * Originally by Hans Häggström, 2010.
 * Dual licenced under Creative Commons Attribution-Share Alike 3.0 and LGPL2 or later
 */

include <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));

// 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;
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, ":"));
}