[nt3d] / serrated.html

<html>
  <head>
    <title>Serrated</title>
    <script type="text/javascript" src="nt3d.js"></script>
    <script type="text/javascript">
      function serrated(params) {
        var tau = 2 * Math.PI;
        var path_length = params.num_serrations * params.steps_per_serration;
        var path = [];
        for (var i = 0; i <= path_length; i++) {
          path[i] = [params.length*i/path_length,0,0];
        }
        var serration_length = params.length / params.num_serrations;
        var serration_half_length = serration_length / 2;
        var serration_radius = serration_half_length / Math.sin(tau * params.arc / 2);
        var serration_max_height = Math.sqrt(serration_radius*serration_radius - serration_half_length*serration_half_length);
        // This emits a Sabre Grind.  TODO: Support a double bevel.
        // http://en.wikipedia.org/wiki/Grind#Typical_grinds
        // http://www.allaboutpocketknives.com/images/aapk_content/blade_bevel.JPG
        var edge_height = params.thickness / (2 * Math.tan(tau * params.edge_bevel_angle));
        function shape(i) {
          var serration_progress = (i % params.steps_per_serration) / params.steps_per_serration;
          var serration_x = serration_progress * serration_length - serration_half_length;
          var serration_height = serration_max_height - Math.sqrt(serration_radius*serration_radius - serration_x*serration_x);
          if (params.arc < 0) serration_height *= -1;
          var blade_height = params.depth + serration_height;
          return [[0,                          0,                  0],
                  [blade_height - edge_height, 0,                  0],
                  [blade_height,               params.thickness/2, 0],
                  [blade_height - edge_height, params.thickness,   0],
                  [0,                          params.thickness,   0]];
        }
      	return nt3d.extrude(path, shape, [1,0,0], [0,0,1]);
      }
      var params = [["length", 100, ],
                    ["thickness", 2],
                    ["depth", 10],
                    ["num_serrations", 10],
                    ["arc", .2, "Arc of Each Serration (in turns)"],
                    ["steps_per_serration", 11],
                    ["edge_bevel_angle", .05, "Edge Bevel Angle (in turns)"]];
    </script>
  </head>
  <body onload="nt3d.framework(serrated, params)">
    <h1>Serrated</h1>
    <p>Make a serrated blade.</p>
  </body>
</html>
Commit	Line	Data
8d119f4c SW	1	<html>
	2	<head>
	3	<title>Serrated</title>
	4	<script type="text/javascript" src="nt3d.js"></script>
	5	<script type="text/javascript">
3bafa9bd	6	function serrated(params) {
8d119f4c	7	var tau = 2 * Math.PI;
3bafa9bd	8	var path_length = params.num_serrations * params.steps_per_serration;
8d119f4c SW	9	var path = [];
8d119f4c SW	10	for (var i = 0; i <= path_length; i++) {
3bafa9bd	11	path[i] = [params.length*i/path_length,0,0];
8d119f4c	12	}
3bafa9bd	13	var serration_length = params.length / params.num_serrations;
8d119f4c	14	var serration_half_length = serration_length / 2;
3bafa9bd	15	var serration_radius = serration_half_length / Math.sin(tau * params.arc / 2);
8d119f4c SW	16	var serration_max_height = Math.sqrt(serration_radiusserration_radius - serration_half_lengthserration_half_length);
	17	// This emits a Sabre Grind. TODO: Support a double bevel.
	18	// http://en.wikipedia.org/wiki/Grind#Typical_grinds
	19	// http://www.allaboutpocketknives.com/images/aapk_content/blade_bevel.JPG
3bafa9bd	20	var edge_height = params.thickness / (2 * Math.tan(tau * params.edge_bevel_angle));
8d119f4c	21	function shape(i) {
3bafa9bd	22	var serration_progress = (i % params.steps_per_serration) / params.steps_per_serration;
8d119f4c SW	23	var serration_x = serration_progress * serration_length - serration_half_length;
8d119f4c SW	24	var serration_height = serration_max_height - Math.sqrt(serration_radiusserration_radius - serration_xserration_x);
3bafa9bd SW	25	if (params.arc < 0) serration_height *= -1;
	26	var blade_height = params.depth + serration_height;
	27	return [[0, 0, 0],
	28	[blade_height - edge_height, 0, 0],
	29	[blade_height, params.thickness/2, 0],
	30	[blade_height - edge_height, params.thickness, 0],
	31	[0, params.thickness, 0]];
8d119f4c SW	32	}
	33	return nt3d.extrude(path, shape, [1,0,0], [0,0,1]);
	34	}
3bafa9bd SW	35	var params = [["length", 100, ],
	36	["thickness", 2],
	37	["depth", 10],
	38	["num_serrations", 10],
	39	["arc", .2, "Arc of Each Serration (in turns)"],
	40	["steps_per_serration", 11],
	41	["edge_bevel_angle", .05, "Edge Bevel Angle (in turns)"]];
8d119f4c SW	42	</script>
	43	</head>
	44	<body onload="nt3d.framework(serrated, params)">
	45	<h1>Serrated</h1>
	46	<p>Make a serrated blade.</p>
	47	</body>
	48	</html>