diff --git a/hooks.scad b/hooks.scad index 0fed9c3..8eadb9d 100644 --- a/hooks.scad +++ b/hooks.scad @@ -1,4 +1,3 @@ -include ////////////////////////////////////////////////////////////////////// // LibFile: hooks.scad // Functions and modules for creating hooks and hook like parts. @@ -25,21 +24,26 @@ include // In order to calculate a tangent where the base joins the cylinder, // the lower corners of the base must be outside the cylinder (see Example 3). This scenario occurs when // the base is narrower than the Y-cylinder and hole_z is less than Y-cylinder radius. Also, hole_z must -// be large enough to accommodate hole rounding and base rounding. +// be large enough to accommodate hole rounding and base rounding. +// . +// The roundings use `$fn`, `$fa` and `$fs`, but if you want to explicitly control the outer shape of the hook +// you can separately specify a facet count for the curved portion using `outside_segments`. // Arguments: // base_size = 2-vector specifying x and y sizes of the base // hole_z = distance in the z direction from the base to the center of the hole // or = radius of the cylindrical portion of the part (or zero to create no hole) // --- // od = diameter of the cylindrical portion of the part -// ir, id = optional radius/diameter of the center hole +// ir / id = optional radius/diameter of the center hole +// wall = set thickness of the wall around the central hole // hole = Set to "circle" for a circle hole, "D" for a D-shaped (semicircular) hole or a path to create a custom hole. Default: "circle" -// rounding = rounding of the vertical-ish edges of the prismoid and the exposed edges of the cylinder -// fillet = base rounding, set negative to form a rounded edge instead of fillet -// hole_rounding = rounding of the optional hole -// anchor = Translate so anchor point is at origin (0,0,0). See [anchor](attachments.scad#subsection-anchor). Default: `CENTER` -// spin = Rotate this many degrees around the Z axis. See [spin](attachments.scad#subsection-spin). Default: `0` -// orient = Vector to rotate top towards. See [orient](attachments.scad#subsection-orient). Default: `UP` +// rounding = rounding of the vertical-ish edges of the prismoid and the exposed edges of the cylinder. Default: 0 +// fillet = base fillet. If negative produces a rounded edge instead of a fillet. Default: 0 +// hole_rounding = rounding of the optional hole. Default: 0 +// outside_segments = number of segments to use for the outer curved part of the hook instead of using `$fn`, `$fa` and `$fs`. +// anchor = Translate so anchor point is at origin (0,0,0). See [anchor](attachments.scad#subsection-anchor). Default: CENTER +// spin = Rotate this many degrees around the Z axis. See [spin](attachments.scad#subsection-spin). Default: 0 +// orient = Vector to rotate top towards. See [orient](attachments.scad#subsection-orient). Default: UP // Named anchors: // hole_front = front, center of the cylindrical portion of the part (same as the part FRONT if hole_z=or) // hole_back = back, center of the cylindrical portion of the part (same as the part BACK if hole_z=or) @@ -50,9 +54,14 @@ include // Example: Ring connector // ring_hook([50, 10], 25, 25, ir=20); // Example: Widen the base, add base fillet, no hole +// $fa=4;$fs=1/2; // ring_hook([70, 10], 25, or=25, ir=0, fillet=3, rounding=1.5); // Example: Narrow base +// $fa=4;$fs=1/2; // ring_hook([40, 10], 25, or=25, ir=0, fillet=3, rounding=1.5); +// Example: Negative fillet value +// $fa=4;$fs=1/2; +// ring_hook([40, 10], 25, or=25, ir=0, fillet=-3, rounding=1.5); // Example(3D,VPR=[90,0,0]): If the base is narrower than the cylinder diameter then its corners have to be outside the cylinder for this shape to be defined because it requires a tangent line to the cylinder. This example shows a valid base corner point in blue. An invalid corner point appears in red: no tangent to the circle exists through the red point. // hole_z = 20; // base_size = [40, 10]; @@ -77,13 +86,18 @@ include // ring_hook([50, 10], 1, 25, ir=0); // ring_hook([50, 10], 1, 25, ir=15, hole="D"); // } -// Example: hole_z must be greater than ir + hole_rounding + fillet when hole="circle". Here hole_z is only 1 larger than the minimum. +// Example: hole_z must be greater than ir + hole_rounding + fillet when hole="circle". Here hole_z is only 1 larger than the minimum. +// $fs=1;$fa=5; // ring_hook([50, 10], hole_z=27, or=25, ir=20, hole_rounding=3, fillet=3); // Example: Rounding all edges // ring_hook([50, 10], 40, 25, ir=15, rounding=5, hole_rounding=5, fillet=5); // Example: Giving an arbitrary path for the hole, in this case an octagon to make the object printable without support. -// ring_hook([50, 20],30, 25, ir=10, hole=octagon(side=10,realign=true), hole_rounding=3, rounding=4) ; -// Example: The ring_hook includes 4 custom anchors: front & back at the center of the cylinder component and left & right at the tangent points. +// ring_hook([50, 20],30, 25, hole=octagon(side=10,realign=true), hole_rounding=3, rounding=4) ; +// Example: Using `outside_segments` +// $fs=.2;$fa=2; +// ring_hook(base_size=[40,10],hole_z=14, od=29,hole=rect(12), +// rounding=1,hole_rounding=1,fillet=1,outside_segments=3); +// Example(3D,Med): The ring_hook includes 4 custom anchors: front & back at the center of the cylinder component and left & right at the tangent points. // ring_hook([55, 10], 12, 25, ir=0) show_anchors(std=false); // Example: Use the custom anchor to place a screw hole // include @@ -105,18 +119,27 @@ include // parent(), RIGHT, fillet=1); +function ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", + rounding=0, fillet=0, hole_rounding=0, outside_segments, + anchor=BOTTOM, spin=0, orient=UP) = no_function("ring_hook"); module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", - rounding=0, fillet=0, hole_rounding=0, - anchor=BOTTOM, spin=0, orient=UP) { - + rounding=0, fillet=0, hole_rounding=0, outside_segments, + anchor=BOTTOM, spin=0, orient=UP) +{ or_tmp = get_radius(r=or, d=od); ir_tmp = get_radius(r=ir, d=id); - dummy = assert(num_defined([ir_tmp, or_tmp, wall])==2, "Must define exactly two of r/d, ir/id and wall"); - ir = is_def(ir_tmp) ? ir_tmp : or_tmp - wall; + dummy = assert(is_path(hole) || num_defined([ir_tmp, or_tmp, wall])==2, + "Must define exactly two of or/od, ir/id and wall (unless you give a custom hole)") + assert(!is_path(hole) || num_defined([ir_tmp, wall])==0, + "Canot define ir/id or wall with a custom hole"); + ir = is_path(hole) ? 0 + : is_def(ir_tmp) ? ir_tmp + : or_tmp - wall; or = is_def(or_tmp) ? or_tmp : ir + wall; - dummy2 = assert(ir <= or, "Hole doesn't fit or wall size is negative") + dummy2 = assert(is_path(hole) || ir <= or, "Hole doesn't fit or wall size is negative") assert(sqrt((0.5*base_size.x)^2 + hole_z^2) > or, "Base corners must be outside the cylinder") assert(in_list(hole,["circle","D"]) || is_path(hole,2), "hole must be \"circle\", \"D\" or a 2d path") + assert(is_undef(outside_segments) || outside_segments>=2, "outside_segments must be at least 2") assert(all_nonnegative([hole_rounding]), "hole_rounding must be greater than or equal to 0"); if (ir > 0 && hole=="circle") @@ -147,7 +170,10 @@ module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", right_tang_dir = unit([tangent.x, 0, tangent.y-hole_z]); left_tang_dir = unit([-tangent.x,0, tangent.y-hole_z]); - + + prism_steps = segs(max(rounding,abs(fillet)),90); + hole_rounding_steps = segs(hole_rounding,90); + anchors = [ named_anchor("hole_front", [0, -w/2, z_offset], FRONT, 0), named_anchor("hole_back", [0, w/2, z_offset], BACK, 180), @@ -171,16 +197,17 @@ module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", ]; - profile = is_path(hole) ? hole + + hole = is_path(hole) ? hole : hole=="D" ? arc(angle=180, r=ir, rounding=hole_rounding, wedge=true) : ir > 0 ? circle(ir) : undef; - parts = is_undef(profile) ? undef + parts = is_undef(hole) ? undef :[ define_part("inner", attach_geom( - region=[ymove(z_offset,profile)], l=size.y), + region=[ymove(z_offset,hole)], l=size.y), T=xrot(90), inside=true) ]; @@ -197,7 +224,7 @@ module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", union() { startangle = atan2(tangent.y-hole_z, tangent.x); endangle = posmod(atan2(tangent.y-hole_z, -tangent.x),360); - steps = segs(or,endangle-startangle)+1; + steps = 1+first_defined([outside_segments,segs(or,endangle-startangle)]); delta = (endangle-startangle)/(steps-1); @@ -209,7 +236,7 @@ module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", [or-rounding,0,-base_size.y/2], [or,0,-base_size.y/2], [or,0,-base_size.y/2+rounding]],0.92), - pts = bezier_curve(bez) + pts = bezier_curve(bez,splinesteps=prism_steps) ) concat(pts, reverse(zflip(pts))); @@ -224,7 +251,7 @@ module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", intersection(){ up(hole_z)xrot(90) vnf_vertex_array(transpose(toplist),caps=true,col_wrap=true,reverse=true,triangulate=true); - cuboid([max(base_size.x,2*or),w+1, or+hole_z+1],anchor=BOT); + up(abs(fillet))cuboid([max(base_size.x,2*or),w+1, or+hole_z+1],anchor=BOT); } // When base is outside the circle the base needs to be clipped so the roundings don't interfere @@ -245,7 +272,7 @@ module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", joint_bot=-fillet, joint_sides=rounding, k_sides=0.92, k_bot=0.92, - anchor=BOT ); + anchor=BOT,splinesteps=prism_steps); if (startangle>0) xflip_copy() vnf_vertex_array([fwd(w/2+1, maskpath), back(w/2+1, maskpath)], @@ -253,13 +280,13 @@ module ring_hook(base_size, hole_z, or, ir, od, id, wall, hole="circle", } } - if (ir > 0) { + if (is_def(hole)) { up(hole_z) prism_connector( - profile, + hole, parent(), FRONT, parent(), BACK, - fillet=hole_rounding); + fillet=hole_rounding, n=hole_rounding_steps); } } children();