| | 1 | <html> |
| | 2 | <head> |
| | 3 | <title>The Thing the Rostock Was Printing in Make Magazine</title> |
| | 4 | <script type="text/javascript" src="nt3d.js"></script> |
| | 5 | <script type="text/javascript"> |
| | 6 | function pointy_sin(x) { |
| | 7 | // Similar to sin(x*pi) over the range [-1,1], |
| | 8 | // but with more movement towards the extremes. |
| | 9 | // https://plus.google.com/101508799331795210529/posts/Yg7LmV8BpTw |
| | 10 | return 3.7*x + (Math.log(1-.95*x)-Math.log(.95*x+1)); |
| | 11 | } |
| | 12 | function rmm(base_separation, base_offset, |
| | 13 | width, short_arc_height, tall_arc_height, |
| | 14 | tube_width, steps_along, steps_around) { |
| | 15 | var tau = Math.PI*2; |
| | 16 | var path = []; |
| | 17 | // Short arc |
| | 18 | for (var i = 0; i < steps_along; i++) { |
| | 19 | var progress = i/steps_along; |
| | 20 | var x_separation = Math.cos(progress*tau/2)*base_separation; |
| | 21 | var y_offset = -Math.sin(progress*tau/4)*base_offset; |
| | 22 | var y_arc = Math.sin(progress*tau)*width; |
| | 23 | var z_arc = -Math.cos(progress*tau)*short_arc_height + short_arc_height; |
| | 24 | path.push([x_separation, y_offset + y_arc, z_arc]); |
| | 25 | } |
| | 26 | // Tall arc |
| | 27 | for (var i = 0; i < steps_along; i++) { |
| | 28 | var progress = i/steps_along; |
| | 29 | var x_arc = -Math.cos(progress*tau*1.5)*base_separation; |
| | 30 | var y_offset = -Math.cos(progress*tau/4)*base_offset; |
| | 31 | var y_twist = -pointy_sin(progress*2 - 1)*width/2; |
| | 32 | var z_arc = -Math.cos(progress*tau)*tall_arc_height + tall_arc_height; |
| | 33 | path.push([x_arc, y_offset + y_twist, z_arc]); |
| | 34 | } |
| | 35 | return nt3d.closed_extrude( |
| | 36 | path, |
| | 37 | nt3d.circle(tube_width, steps_around), |
| | 38 | nt3d.shapenormals_from_closed_path(path), |
| | 39 | nt3d.pathnormals_from_point(path, [0,0,0])); |
| | 40 | } |
| | 41 | var params = [["Base separation", 30], |
| | 42 | ["Base offset", 10], |
| | 43 | ["Width", 40], |
| | 44 | ["Short arc height", 60], |
| | 45 | ["Tall arc height", 80], |
| | 46 | ["Tube width", 10], |
| | 47 | ["Steps along each arc", 70], |
| | 48 | ["Steps around", 12]]; |
| | 49 | </script> |
| | 50 | </head> |
| | 51 | <body onload="nt3d.framework(rmm, params)"> |
| | 52 | <h1>The Thing the Rostock Was Printing in Make Magazine</h1> |
| | 53 | <p><a href="http://www.flickr.com/photos/jcrocholl/8065968929/sizes/l/in/photostream/">This thing</a>.</p> |
| | 54 | <!-- My notes after staring at it: |
| | 55 | x y z |
| | 56 | 1 0 0 Bottom front |
| | 57 | .5 1 .5s 1/4 up short arc |
| | 58 | 0 0 s Top of short arc |
| | 59 | -.5 -1 .5s Coming down short arc |
| | 60 | -1 0 0 Bottom back |
| | 61 | 1 .33 .5t 1/4 up long arc |
| | 62 | 0 0 t Top of tall arc |
| | 63 | -1 -.33 .5t Coming down tall arc |
| | 64 | 1 0 0 Bottom front (Repeated from above) |
| | 65 | |
| | 66 | x = cos over 1/2 period for short arc, -cos over 1.5 periods for tall arc |
| | 67 | y = sin over 1 period for short arc, sin/3 over 1 period for tall arc |
| | 68 | z = -cos over 1 period for short arc, -cos over 1 period for tall arc |
| | 69 | --> |
| | 70 | </body> |
| | 71 | </html> |
| | 72 | |
projects / nt3d / blame_incremental