BOSL2/edges.scad
2020-09-22 00:21:12 -07:00

407 lines
14 KiB
OpenSCAD

//////////////////////////////////////////////////////////////////////
// LibFile: edges.scad
// Routines to work with edge sets and edge set descriptors.
// To use this, add the following line to the top of your file.
// ```
// include <BOSL2/std.scad>
// ```
//////////////////////////////////////////////////////////////////////
// CommonCode:
// module text3d(txt,size=3) {
// if (is_list(txt)) {
// for (i=idx(txt)) {
// down((i-len(txt)/2+1)*size*1.25) {
// text3d(txt[i], size=size);
// }
// }
// } else {
// xrot(90) color("#000")
// linear_extrude(height=0.1) {
// text(text=txt, size=size, halign="center", valign="center");
// }
// }
// }
// module edge_cube(size=20, chamfer=3, txtsize=3, edges="ALL") {
// lbl = is_string(edges)? [str("\"",edges,"\"")] : concat(
// edges.z>0? ["TOP"] : edges.z<0? ["BTM"] : [],
// edges.y>0? ["BACK"] : edges.y<0? ["FWD"] : [],
// edges.x>0? ["RIGHT"] : edges.x<0? ["LEFT"] : []
// );
// lbl2 = [for (i=idx(lbl)) i<len(lbl)-1? str(lbl[i],"+") : lbl[i]];
// cuboid(size=size,chamfer=chamfer,edges=edges);
// fwd(size/2) text3d(lbl2, size=txtsize);
// }
// module corner_cube(size=20, txtsize=3, corners="ALL") {
// corner_set = _corner_set(corners);
// lbl = is_string(corners)? [str("\"",corners,"\"")] : concat(
// corners.z>0? ["TOP"] : corners.z<0? ["BTM"] : [],
// corners.y>0? ["BACK"] : corners.y<0? ["FWD"] : [],
// corners.x>0? ["RIGHT"] : corners.x<0? ["LEFT"] : []
// );
// lbl2 = [for (i=idx(lbl)) i<len(lbl)-1? str(lbl[i],"+") : lbl[i]];
// for (i=[0:7]) if (corner_set[i]>0)
// translate(CORNER_OFFSETS[i]*size/2)
// color("red")
// cube(1, center=true);
// fwd(size/2) text3d(lbl2, size=txtsize);
// color("yellow",0.7) cuboid(size=size);
// }
// Section: Sets of Edges
// Constants for specifying edges for `cuboid()`, etc.
EDGES_NONE = [[0,0,0,0], [0,0,0,0], [0,0,0,0]]; // No edges.
EDGES_ALL = [[1,1,1,1], [1,1,1,1], [1,1,1,1]]; // All edges.
// Section: Edge Helpers
// Function: is_edge_array()
// Usage:
// is_edge_array(v)
// Description:
// Returns true if the given value has the form of an edge array.
function is_edge_array(v) = is_list(v) && is_vector(v[0]) && len(v)==3 && len(v[0])==4;
function _edge_set(v) =
is_edge_array(v)? v : [
for (ax=[0:2]) [
for (b=[-1,1], a=[-1,1]) let(
v2=[[0,a,b],[a,0,b],[a,b,0]][ax]
) (
is_string(v)? (
v=="X"? (ax==0) : // Return all X axis aligned edges.
v=="Y"? (ax==1) : // Return all Y axis aligned edges.
v=="Z"? (ax==2) : // Return all Z axis aligned edges.
v=="ALL"? true : // Return all edges.
v=="NONE"? false : // Return no edges.
let(valid_values = ["X", "Y", "Z", "ALL", "NONE"])
assert(
in_list(v, valid_values),
str(v, " must be a vector, edge array, or one of ", valid_values)
) v
) :
let(nonz = sum(vabs(v)))
nonz==2? (v==v2) : // Edge: return matching edge.
let(
matches = count_true([
for (i=[0:2]) v[i] && (v[i]==v2[i])
])
)
nonz==1? (matches==1) : // Face: return surrounding edges.
(matches==2) // Corner: return touching edges.
)? 1 : 0
]
];
// Function: normalize_edges()
// Usage:
// normalize_edges(v);
// Description:
// Normalizes all values in an edge array to be `1`, if it was originally greater than `0`,
// or `0`, if it was originally less than or equal to `0`.
function normalize_edges(v) = [for (ax=v) [for (edge=ax) edge>0? 1 : 0]];
// Function: edges()
// Usage:
// edges(v)
// edges(v, except)
// Description:
// Takes a list of edge set descriptors, and returns a normalized edges array
// that represents all those given edges. If the `except` argument is given
// a list of edge set descriptors, then all those edges will be removed
// from the returned edges array. If either argument only has a single edge
// set descriptor, you do not have to pass it in a list.
// Each edge set descriptor can be any of:
// - A vector pointing towards an edge.
// - A vector pointing towards a face, indicating all edges surrounding that face.
// - A vector pointing towards a corner, indicating all edges touching that corner.
// - The string `"X"`, indicating all X axis aligned edges.
// - The string `"Y"`, indicating all Y axis aligned edges.
// - The string `"Z"`, indicating all Z axis aligned edges.
// - The string `"ALL"`, indicating all edges.
// - The string `"NONE"`, indicating no edges at all.
// - A raw edges array, where each edge is represented by a 1 or a 0. The edge ordering is:
// ```
// [
// [Y-Z-, Y+Z-, Y-Z+, Y+Z+],
// [X-Z-, X+Z-, X-Z+, X+Z+],
// [X-Y-, X+Y-, X-Y+, X+Y+]
// ]
// ```
// Figure(3DBig): Edge Vectors
// ydistribute(50) {
// xdistribute(30) {
// edge_cube(edges=BOT+RIGHT);
// edge_cube(edges=BOT+BACK);
// edge_cube(edges=BOT+LEFT);
// edge_cube(edges=BOT+FRONT);
// }
// xdistribute(30) {
// edge_cube(edges=FWD+RIGHT);
// edge_cube(edges=BACK+RIGHT);
// edge_cube(edges=BACK+LEFT);
// edge_cube(edges=FWD+LEFT);
// }
// xdistribute(30) {
// edge_cube(edges=TOP+RIGHT);
// edge_cube(edges=TOP+BACK);
// edge_cube(edges=TOP+LEFT);
// edge_cube(edges=TOP+FRONT);
// }
// }
// Figure(3DBig): Corner Vector Edge Sets
// ydistribute(50) {
// xdistribute(30) {
// edge_cube(edges=FRONT+LEFT+TOP);
// edge_cube(edges=FRONT+RIGHT+TOP);
// edge_cube(edges=FRONT+LEFT+BOT);
// edge_cube(edges=FRONT+RIGHT+BOT);
// }
// xdistribute(30) {
// edge_cube(edges=TOP+LEFT+BACK);
// edge_cube(edges=TOP+RIGHT+BACK);
// edge_cube(edges=BOT+LEFT+BACK);
// edge_cube(edges=BOT+RIGHT+BACK);
// }
// }
// Figure(3D): Face Vector Edge Sets
// ydistribute(50) {
// xdistribute(30) {
// edge_cube(edges=LEFT);
// edge_cube(edges=FRONT);
// edge_cube(edges=RIGHT);
// }
// xdistribute(30) {
// edge_cube(edges=TOP);
// edge_cube(edges=BACK);
// edge_cube(edges=BOTTOM);
// }
// }
// Figure(3D): Named Edge Sets
// ydistribute(50) {
// xdistribute(30) {
// edge_cube(edges="X");
// edge_cube(edges="Y");
// edge_cube(edges="Z");
// }
// xdistribute(30) {
// edge_cube(edges="ALL");
// edge_cube(edges="NONE");
// }
// }
// Example: Just the front-top edge
// edges(FRONT+TOP)
// Example: All edges surrounding either the front or top faces
// edges([FRONT,TOP])
// Example: All edges around the bottom face, except any that are also on the front
// edges(BTM, except=FRONT)
// Example: All edges except those around the bottom face.
// edges("ALL", except=BOTTOM)
// Example: All Z-aligned edges except those around the back face.
// edges("Z", except=BACK)
// Example: All edges around the bottom or front faces, except the bottom-front edge.
// edges([BOTTOM,FRONT], except=BOTTOM+FRONT)
// Example: All edges, except Z-aligned edges on the front.
// edges("ALL", except=edges("Z", except=BACK))
function edges(v, except=[]) =
(is_string(v) || is_vector(v) || is_edge_array(v))? edges([v], except=except) :
(is_string(except) || is_vector(except) || is_edge_array(except))? edges(v, except=[except]) :
except==[]? normalize_edges(sum([for (x=v) _edge_set(x)])) :
normalize_edges(
normalize_edges(sum([for (x=v) _edge_set(x)])) -
sum([for (x=except) _edge_set(x)])
);
EDGE_OFFSETS = [ // Array of XYZ offsets to the center of each edge.
[
[ 0,-1,-1],
[ 0, 1,-1],
[ 0,-1, 1],
[ 0, 1, 1]
], [
[-1, 0,-1],
[ 1, 0,-1],
[-1, 0, 1],
[ 1, 0, 1]
], [
[-1,-1, 0],
[ 1,-1, 0],
[-1, 1, 0],
[ 1, 1, 0]
]
];
// Section: Corner Sets
// Constants for specifying corners.
CORNERS_NONE = [0,0,0,0,0,0,0,0]; // No corners.
CORNERS_ALL = [1,1,1,1,1,1,1,1]; // All corners.
// Section: Corner Helpers
// Function: is_corner_array()
// Usage:
// is_corner_array(v)
// Description:
// Returns true if the given value has the form of a corner array.
function is_corner_array(v) = is_vector(v) && len(v)==8 && all([for (x=v) x==1||x==0]);
// Function: normalize_corners()
// Usage:
// normalize_corners(v);
// Description:
// Normalizes all values in a corner array to be `1`, if it was originally greater than `0`,
// or `0`, if it was originally less than or equal to `0`.
function normalize_corners(v) = [for (x=v) x>0? 1 : 0];
function _corner_set(v) =
is_corner_array(v)? v : [
for (i=[0:7]) let(
v2 = CORNER_OFFSETS[i]
) (
is_string(v)? (
v=="ALL"? true : // Return all corners.
v=="NONE"? false : // Return no corners.
let(valid_values = ["ALL", "NONE"])
assert(
in_list(v, valid_values),
str(v, " must be a vector, corner array, or one of ", valid_values)
) v
) :
all([for (i=[0:2]) !v[i] || (v[i]==v2[i])])
)? 1 : 0
];
// Function: corners()
// Usage:
// corners(v)
// corners(v, except)
// Description:
// Takes a list of corner set descriptors, and returns a normalized corners array
// that represents all those given corners. If the `except` argument is given
// a list of corner set descriptors, then all those corners will be removed
// from the returned corners array. If either argument only has a single corner
// set descriptor, you do not have to pass it in a list.
// Each corner set descriptor can be any of:
// - A vector pointing towards an edge indicating both corners at the ends of that edge.
// - A vector pointing towards a face, indicating all the corners of that face.
// - A vector pointing towards a corner, indicating just that corner.
// - The string `"ALL"`, indicating all corners.
// - The string `"NONE"`, indicating no corners at all.
// - A raw corners array, where each corner is represented by a 1 or a 0. The corner ordering is:
// ```
// [X-Y-Z-, X+Y-Z-, X-Y+Z-, X+Y+Z-, X-Y-Z+, X+Y-Z+, X-Y+Z+, X+Y+Z+]
// ```
// Figure(3DBig): Edge Vectors
// ydistribute(55) {
// xdistribute(35) {
// corner_cube(corners=BOT+RIGHT);
// corner_cube(corners=BOT+BACK);
// corner_cube(corners=BOT+LEFT);
// corner_cube(corners=BOT+FRONT);
// }
// xdistribute(35) {
// corner_cube(corners=FWD+RIGHT);
// corner_cube(corners=BACK+RIGHT);
// corner_cube(corners=BACK+LEFT);
// corner_cube(corners=FWD+LEFT);
// }
// xdistribute(35) {
// corner_cube(corners=TOP+RIGHT);
// corner_cube(corners=TOP+BACK);
// corner_cube(corners=TOP+LEFT);
// corner_cube(corners=TOP+FRONT);
// }
// }
// Figure(3DBig): Corner Vector Edge Sets
// ydistribute(55) {
// xdistribute(35) {
// corner_cube(corners=FRONT+LEFT+TOP);
// corner_cube(corners=FRONT+RIGHT+TOP);
// corner_cube(corners=FRONT+LEFT+BOT);
// corner_cube(corners=FRONT+RIGHT+BOT);
// }
// xdistribute(35) {
// corner_cube(corners=TOP+LEFT+BACK);
// corner_cube(corners=TOP+RIGHT+BACK);
// corner_cube(corners=BOT+LEFT+BACK);
// corner_cube(corners=BOT+RIGHT+BACK);
// }
// }
// Figure(3D): Face Vector Edge Sets
// ydistribute(55) {
// xdistribute(35) {
// corner_cube(corners=LEFT);
// corner_cube(corners=FRONT);
// corner_cube(corners=RIGHT);
// }
// xdistribute(35) {
// corner_cube(corners=TOP);
// corner_cube(corners=BACK);
// corner_cube(corners=BOTTOM);
// }
// }
// Figure(3D): Named Edge Sets
// xdistribute(35) {
// corner_cube(corners="ALL");
// corner_cube(corners="NONE");
// }
// Example: Just the front-top-right corner
// corners(FRONT+TOP+RIGHT)
// Example: All corners surrounding either the front or top faces
// corners([FRONT,TOP])
// Example: All corners around the bottom face, except any that are also on the front
// corners(BTM, except=FRONT)
// Example: All corners except those around the bottom face.
// corners("ALL", except=BOTTOM)
// Example: All corners around the bottom or front faces, except those on the bottom-front edge.
// corners([BOTTOM,FRONT], except=BOTTOM+FRONT)
function corners(v, except=[]) =
(is_string(v) || is_vector(v) || is_corner_array(v))? corners([v], except=except) :
(is_string(except) || is_vector(except) || is_corner_array(except))? corners(v, except=[except]) :
except==[]? normalize_corners(sum([for (x=v) _corner_set(x)])) :
let(
a = normalize_corners(sum([for (x=v) _corner_set(x)])),
b = normalize_corners(sum([for (x=except) _corner_set(x)]))
) normalize_corners(a - b);
CORNER_OFFSETS = [ // Array of XYZ offsets to each corner.
[-1,-1,-1], [ 1,-1,-1], [-1, 1,-1], [ 1, 1,-1],
[-1,-1, 1], [ 1,-1, 1], [-1, 1, 1], [ 1, 1, 1]
];
// Function: corner_edges()
// Description:
// Returns [XCOUNT,YCOUNT,ZCOUNT] where each is the count of edges aligned with that axis that are in the edge set and touch the given corner.
// Arguments:
// edges = Standard edges array.
// v = Vector pointing to the corner to count edge intersections at.
function corner_edges(edges, v) =
let(u = (v+[1,1,1])/2) [edges[0][u.y+u.z*2], edges[1][u.x+u.z*2], edges[2][u.x+u.y*2]];
// Function: corner_edge_count()
// Description: Counts how many given edges intersect at a specific corner.
// Arguments:
// edges = Standard edges array.
// v = Vector pointing to the corner to count edge intersections at.
function corner_edge_count(edges, v) =
let(u = (v+[1,1,1])/2) edges[0][u.y+u.z*2] + edges[1][u.x+u.z*2] + edges[2][u.x+u.y*2];
// vim: expandtab tabstop=4 shiftwidth=4 softtabstop=4 nowrap