BOSL2/masks.scad

//////////////////////////////////////////////////////////////////////
// Masking shapes.
//////////////////////////////////////////////////////////////////////

/*
BSD 2-Clause License

Copyright (c) 2017, Revar Desmera
All rights reserved.

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modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this
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*/


include <transforms.scad>
include <shapes.scad>
include <math.scad>


module angle_half_pie_mask(
	ang=45, h=1,
	r=undef, r1=undef, r2=undef,
	d=1.0, d1=undef, d2=undef,
) {
	r  = (r  != undef)? r  : (d/2);
	r1 = (r1 != undef)? r1 : ((d1 != undef)? (d1/2) : r);
	r2 = (r2 != undef)? r2 : ((d2 != undef)? (d2/2) : r);
	rm = max(r1,r2);
	difference() {
		cylinder(h=h, r1=r1, r2=r2, center=true);
		translate([0, -rm/2, 0])
			cube(size=[rm*2+1, rm, h+1], center=true);
		zrot(ang) {
			translate([0, rm/2, 0]) {
				cube(size=[rm*2.1, rm, h+1], center=true);
			}
		}
	}
}


// Creates a pie wedge shape that can be used to mask other shapes.
// You must specify either r or d, or their r1/r2, d1/d2 variants.
//   ang = angle of wedge in degrees.
//   h = height of wedge.
//   r = Radius of circle wedge is created from. (optional)
//   r1 = Bottom radius of cone that wedge is created from.  (optional)
//   r2 = Upper radius of cone that wedge is created from.  (optional)
//   d = Diameter of circle wedge is created from. (optional)
//   d1 = Bottom diameter of cone that wedge is created from.  (optional)
//   d2 = Upper diameter of cone that wedge is created from. (optional)
// Example:
//   angle_pie_mask(ang=30, d=100, h=20);
module angle_pie_mask(
	ang=45, h=1,
	r=undef, r1=undef, r2=undef,
	d=1.0, d1=undef, d2=undef,
) {
	a1 = min(ang, 180.0);
	a2 = max(0.0, ang-180.0);
	r  = (r  != undef)? r  : (d/2);
	r1 = (r1 != undef)? r1 : ((d1 != undef)? (d1/2) : r);
	r2 = (r2 != undef)? r2 : ((d2 != undef)? (d2/2) : r);
	union() {
		angle_half_pie_mask(h=h, r1=r1, r2=r2, ang=a1);
		if (a2 > 0.0) {
			zrot(180) angle_half_pie_mask(h=h, r1=r1, r2=r2, ang=a2);
		}
	}
}


// Creates a shape that can be used to chamfer a 90 degree edge along the Z axis.
// Difference it from the object to be chamfered.  The center of the mask
// object should align exactly with the edge to be chamfered.
//   l = Height of mask
//   chamfer = size of chamfer
// Example:
//   chamfer_mask_z(l=10.0, chamfer=2.0);
module chamfer_mask_z(l=1.0, chamfer=1.0) {
	zrot(45) cube(size=[chamfer*sqrt(2.0), chamfer*sqrt(2.0), l], center=true);
}


// Creates a shape that can be used to chamfer a 90 degree edge along the Y axis.
// Difference it from the object to be chamfered.  The center of the mask
// object should align exactly with the edge to be chamfered.
//   l = Height of mask
//   chamfer = size of chamfer
// Example:
//   chamfer_mask_y(l=10.0, chamfer=2.0);
module chamfer_mask_y(l=1.0, chamfer=1.0) {
	xrot(90) chamfer_mask_z(l=l, chamfer=chamfer);
}


// Creates a shape that can be used to chamfer a 90 degree edge along the X axis.
// Difference it from the object to be chamfered.  The center of the mask
// object should align exactly with the edge to be chamfered.
//   l = Height of mask
//   chamfer = size of chamfer
// Example:
//   chamfer_mask_x(l=10.0, chamfer=2.0);
module chamfer_mask_x(l=1.0, chamfer=1.0) {
	yrot(90) chamfer_mask_z(l=l, chamfer=chamfer);
}


// Chamfers the edges of a cuboid region containing the given children.
//   chamfer = Inset of the chamfer from the edge. (Default: 1)
//   size = The size of the rectangular cuboid we want to chamfer.
//   edges = Which edges do we want to chamfer.  Recommend to use EDGE constants from constants.scad.
//           [
//               [Y+Z+, Y-Z+, Y-Z-, Y+Z-],
//               [X+Z+, X-Z+, X-Z-, X+Z-],
//               [X+Y+, X-Y+, X-Y-, X+Y-]
//           ]
// Example:
//   include <BOSL/constants.scad>
//   chamfer(chamfer=2, size=[10,40,30], edges=EDGE_BOT_BK + EDGE_TOP_RT + EDGE_TOP_LF) {
//     cube(size=[10,40,30], center=true);
//   }
module chamfer(chamfer=1, size=[1,1,1], edges=[[0,0,0,0], [1,1,0,0], [0,0,0,0]])
{
	eps = 0.1;
	x = size[0];
	y = size[1];
	z = size[2];
	lx = x + eps;
	ly = y + eps;
	lz = z + eps;
	difference() {
		union() {
			children();
		}
		union() {
			if (edges[0][0] > 0)
				up(z/2) back(y/2) chamfer_mask_x(l=lx, chamfer=chamfer);
			if (edges[0][1] > 0)
				up(z/2) fwd(y/2) chamfer_mask_x(l=lx, chamfer=chamfer);
			if (edges[0][2] > 0)
				down(z/2) back(y/2) chamfer_mask_x(l=lx, chamfer=chamfer);
			if (edges[0][3] > 0)
				down(z/2) fwd(y/2) chamfer_mask_x(l=lx, chamfer=chamfer);

			if (edges[1][0] > 0)
				up(z/2) right(x/2) chamfer_mask_y(l=ly, chamfer=chamfer);
			if (edges[1][1] > 0)
				up(z/2) left(x/2) chamfer_mask_y(l=ly, chamfer=chamfer);
			if (edges[1][2] > 0)
				down(z/2) right(x/2) chamfer_mask_y(l=ly, chamfer=chamfer);
			if (edges[1][3] > 0)
				down(z/2) left(x/2) chamfer_mask_y(l=ly, chamfer=chamfer);

			if (edges[2][0] > 0)
				back(y/2) right(x/2) chamfer_mask_z(l=lz, chamfer=chamfer);
			if (edges[2][1] > 0)
				back(y/2) left(x/2) chamfer_mask_z(l=lz, chamfer=chamfer);
			if (edges[2][2] > 0)
				fwd(y/2) right(x/2) chamfer_mask_z(l=lz, chamfer=chamfer);
			if (edges[2][3] > 0)
				fwd(y/2) left(x/2) chamfer_mask_z(l=lz, chamfer=chamfer);
		}
	}
}


// Create a mask that can be used to bevel/chamfer the edge of a circular hole.
// Difference it from the hole to be chamferred.  The center of the mask object
// should align exactly with the center of the end of the hole to be chamferred.
//   r = radius of hole to chamfer.
//   d = Diameter of hole to chamfer. Use instead of r.
//   chamfer = size of the edge chamferred. (Default: 0.25)
// Example:
//   $fa=2; $fs=2;
//   difference() {
//       cube([150,150,100], center=true);
//       cylinder(r=50, h=100.1, center=true);
//       up(50) chamfer_hole_mask(r=50, chamfer=10);
//   }
module chamfer_hole_mask(r=1.0, d=undef, chamfer=0.25)
{
	r = d==undef? r : d/2;
	down(chamfer) cylinder(r1=r, r2=r+chamfer, h=chamfer+0.01, center=false);
}


// Create a mask that can be used to bevel/chamfer the end of a cylinder.
// Difference it from the cylinder to be chamferred.  The center of the mask object
// should align exactly with the center of the end of the cylinder to be chamferred.
//   r = radius of hole to chamfer.
//   d = Diameter of hole to chamfer. Use instead of r.
//   chamfer = size of the edge chamferred. (Default: 0.25)
// Example:
//   $fa=2; $fs=2;
//   difference() {
//       cylinder(r=50, h=100, center=true);
//       up(50) chamfer_cylinder_mask(r=50, chamfer=10);
//   }
module chamfer_cylinder_mask(r=1.0, d=undef, chamfer=0.25)
{
	r = d==undef? r : d/2;
	difference() {
		cube([2*r+1, 2*r+1, 2*chamfer], center=true);
		down(chamfer+0.01) cylinder(r1=r, r2=r-chamfer, h=chamfer, center=false);
	}
}


// Creates a shape that can be used to fillet a vertical 90 degree edge.
// Difference it from the object to be filletted.  The center of the mask
// object should align exactly with the edge to be filletted.
//   h = height of vertical mask.
//   r = radius of the fillet.
//   center = If true, vertically center mask.
// Example:
//   difference() {
//       cube(size=100, center=false);
//       up(50) fillet_mask(h=100.1, r=25.0);
//   }
module fillet_mask(h=1.0, r=1.0, center=true)
{
	n = ceil(segs(r)/4)*4;
	linear_extrude(height=h, convexity=4, center=center) {
		polygon(
			points=concat(
				[for (a = [  0:360/n: 90]) [r*cos(a)-r, r*sin(a)-r]],
				[for (a = [270:360/n:360]) [r*cos(a)-r, r*sin(a)+r]],
				[for (a = [180:360/n:270]) [r*cos(a)+r, r*sin(a)+r]],
				[for (a = [ 90:360/n:180]) [r*cos(a)+r, r*sin(a)-r]]
			)
		);
	}
}
module fillet_mask_z(l=1.0, r=1.0) fillet_mask(h=l, r=r, center=true);
module fillet_mask_y(l=1.0, r=1.0) xrot(90) fillet_mask(h=l, r=r, center=true);
module fillet_mask_x(l=1.0, r=1.0) yrot(90) fillet_mask(h=l, r=r, center=true);


// Creates a vertical mask that can be used to fillet the edge where two
// face meet, at any arbitrary angle.  Difference it from the object to
// be filletted.  The center of the mask should align exactly with the
// edge to be filletted.
//   h = height of vertical mask.
//   r = radius of the fillet.
//   ang = angle that the planes meet at.
//   center = If true, vertically center mask.
// Example:
//   difference() {
//       angle_pie_mask(ang=70, h=50, d=100);
//       fillet_angled_edge_mask(h=51, r=20.0, ang=70, $fn=32);
//   }
module fillet_angled_edge_mask(h=1.0, r=1.0, ang=90, center=true)
{
	sweep = 180-ang;
	n = ceil(segs(r)*sweep/360);
	x = r*sin(90-(ang/2))/sin(ang/2);
	linear_extrude(height=h, convexity=4, center=center) {
		polygon(
			points=concat(
				[for (i = [0:n]) let (a=90+ang+i*sweep/n) [r*cos(a)+x, r*sin(a)+r]],
				[for (i = [0:n]) let (a=90+i*sweep/n) [r*cos(a)+x, r*sin(a)-r]],
				[
					[min(-1, r*cos(270-ang)+x-1), r*sin(270-ang)-r],
					[min(-1, r*cos(90+ang)+x-1), r*sin(90+ang)+r],
				]
			)
		);
	}
}


// Creates a shape that can be used to fillet the corner of an angle.
// Difference it from the object to be filletted.  The center of the mask
// object should align exactly with the point of the corner to be filletted.
//   fillet = radius of the fillet.
//   ang = angle between planes that you need to fillet the corner of.
// Example:
//   ang=60;
//   difference() {
//       angle_pie_mask(ang=ang, h=50, r=200);
//       up(50/2) {
//           fillet_angled_corner_mask(fillet=20, ang=ang);
//           zrot_copies([0, ang]) right(200/2) fillet_mask_x(l=200, r=20);
//       }
//       fillet_angled_edge_mask(h=51, r=20, ang=ang);
//   }
module fillet_angled_corner_mask(fillet=1.0, ang=90)
{
	dx = fillet / tan(ang/2);
	fn = quantup(segs(fillet), 4);
	difference() {
		down(fillet) cylinder(r=dx/cos(ang/2)+1, h=fillet+1, center=false);
		yflip_copy() {
			translate([dx, fillet, -fillet]) {
				hull() {
					sphere(r=fillet, $fn=fn);
					down(fillet*3) sphere(r=fillet, $fn=fn);
					zrot_copies([0,ang]) {
						right(fillet*3) sphere(r=fillet, $fn=fn);
					}
				}
			}
		}
	}
}


// Creates a shape that you can use to round 90 degree corners on a fillet.
// Difference it from the object to be filletted.  The center of the mask
// object should align exactly with the corner to be filletted.
//   r = radius of corner fillet.
// Example:
//   $fa=1; $fs=1;
//   difference() {
//     cube(size=[6,10,16], center=true);
//     translate([0, 5, 8]) yrot(90) fillet_mask(h=7, r=3);
//     translate([3, 0, 8]) xrot(90) fillet_mask(h=11, r=3);
//     translate([3, 5, 0]) fillet_mask(h=17, r=3);
//     translate([3, 5, 8]) fillet_corner_mask(r=3);
//   }
module fillet_corner_mask(r=1.0)
{
	difference() {
		cube(size=r*2, center=true);
		grid_of(count=[2,2,2], spacing=r*2-0.05) {
			sphere(r=r, center=true);
		}
	}
}
//!fillet_corner_mask(r=10.0);


// Create a mask that can be used to round the end of a cylinder.
// Difference it from the cylinder to be filletted.  The center of the
// mask object should align exactly with the center of the end of the
// cylinder to be filletted.
//   r = radius of cylinder to fillet. (Default: 1.0)
//   fillet = radius of the edge filleting. (Default: 0.25)
//   xtilt = angle of tilt of end of cylinder in the X direction. (Default: 0)
//   ytilt = angle of tilt of end of cylinder in the Y direction. (Default: 0)
// Example:
//   $fa=2; $fs=2;
//   difference() {
//     cylinder(r=50, h=100, center=true);
//     up(50) !fillet_cylinder_mask(r=50, fillet=10, xtilt=30);
//   }
module fillet_cylinder_mask(r=1.0, fillet=0.25, xtilt=0, ytilt=0)
{
	dhx = 2*r*sin(xtilt);
	dhy = 2*r*sin(ytilt);
	dh = hypot(dhy, dhx);
	down(dh/2) {
		skew_xz(za=xtilt) {
			skew_yz(za=ytilt) {
				down(fillet) {
					difference() {
						up((dh+2*fillet)/2) {
							cube(size=[r*2+10, r*2+10, dh+2*fillet], center=true);
						}
						torus(or=r, ir=r-2*fillet);
						cylinder(r=r-fillet, h=2*fillet, center=true);
					}
				}
			}
		}
	}
}



// Create a mask that can be used to round the edge of a circular hole.
// Difference it from the hole to be filletted.  The center of the
// mask object should align exactly with the center of the end of the
// hole to be filletted.
//   r = radius of hole to fillet. (Default: 1.0)
//   fillet = radius of the edge filleting. (Default: 0.25)
//   xtilt = angle of tilt of end of cylinder in the X direction. (Default: 0)
//   ytilt = angle of tilt of end of cylinder in the Y direction. (Default: 0)
// Example:
//   $fa=2; $fs=2;
//   difference() {
//     cube([150,150,100], center=true);
//     cylinder(r=50, h=100.1, center=true);
//     up(50) fillet_hole_mask(r=50, fillet=10, xtilt=0, ytilt=0);
//   }
module fillet_hole_mask(r=1.0, fillet=0.25, xtilt=0, ytilt=0)
{
	skew_xz(za=xtilt) {
		skew_yz(za=ytilt) {
			difference() {
				cylinder(r=r+fillet, h=2*fillet, center=true);
				down(fillet) torus(ir=r, or=r+2*fillet);
			}
		}
	}
}


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