// Fixed Angle Line Tool Macro
//
// This tool macro allows you to draw lines with constant angle. 
// To change the angle, open the tool's options dialog by double 
// clicking on the tool icon, or adjust the angle manually by pressing 
// the 'alt' key while dragging the mouse. While dragging, the 'shift' 
// key will measure the current line. You can change the length of
// an existing line, while keeping it at the same angle, by clicking
// on the end of the line and dragging. You have to click within five
// pixels from the lines's end point. 

  var angle = 0;  // degrees
  var a = angle*PI/180;  // radians
  var leftClick = 16;
  var x1,y1,x2,y2;

  macro 'Fixed Angle Line Tool - C000L05f0L0af5' {
    getCursorLoc(x, y, z, flags);
    getLine(x1, y1, x2, y2, lineWidth);
    if ((x2-x)*(x2-x)>25||(y2-y)*(y2-y)>25) { x1=x;y1=y;}
    while (true) {
       getCursorLoc(x2, y2, z, flags);
       if (flags&leftClick==0) exit();
       if (x2!=x1 || y2!=y1) {
          dx=(x2-x1); dy=(y2-y1);
          if (isKeyDown('alt')) {
             makeLine(x1,y1,x2,y2);
             a=atan2(dy,dx);
          } else if (isKeyDown('shift')) {
             run ('Measure');
          } else {
             d=sqrt(dx*dx+dy*dy);
             makeLine(x1,y1,x1+d*cos(a),y1+d*sin(a));
          }
       }
       wait(10);
     }
  }

  macro 'Fixed Angle Line Tool Options' {
    da=180*a/PI;
    da=getNumber("Fixed angle",da);
    a= PI*da/180;
  }