BOSL2/constants.scad
Adrian Mariano 428649e97b fix
2024-10-03 23:00:16 -04:00

292 lines
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OpenSCAD

//////////////////////////////////////////////////////////////////////
// LibFile: constants.scad
// Constants for directions (used with anchoring), and for specifying line termination for
// use with geometry.scad.
// Includes:
// include <BOSL2/std.scad>
// FileGroup: Basic Modeling
// FileSummary: Constants provided by the library
// FileFootnotes: STD=Included in std.scad
//////////////////////////////////////////////////////////////////////
// a value that the user should never enter randomly;
// result of `dd if=/dev/random bs=32 count=1 |base64` :
_UNDEF="LRG+HX7dy89RyHvDlAKvb9Y04OTuaikpx205CTh8BSI";
// Section: General Constants
// Constant: $slop
// Synopsis: The slop amount to make printed items fit closely. `0.0` by default.
// Topics: Constants
// Description:
// A number of printers, particularly FDM/FFF printers, tend to be a bit sloppy in their printing.
// This has made it so that some parts won't fit together without adding a bit of extra slop space.
// That is what the `$slop` value is for. The value for this will vary from printer to printer.
// By default, we use a value of 0.00 so that parts should fit exactly for resin and other precision
// printers. This value is measured in millimeters. When making your own parts, you should add
// `$slop` to both sides of a hole that another part is to fit snugly into. For a loose fit, add
// `2*$slop` to each side. This should be done for both X and Y axes. The Z axis will require a
// slop that depends on your layer height and bridging settings, and hole sizes. We leave that as
// a more complicated exercise for the user.
// .
// Note that the slop value is accessed using the {{get_slop()}} function. This function provides
// the default value of 0 if you have not set `$slop`. This approach makes it possible for you to
// set `$slop` in your programs without experiencing peculiar OpenSCAD issues having to do with multiple
// definitions of the variable. If you write code that uses `$slop` be sure to reference it using {{get_slop()}}.
// DefineHeader(NumList): Calibration
// Calibration: To calibrate the `$slop` value for your printer, follow this procedure:
// Print the Slop Calibration part from the example below.
// Take the long block and orient it so the numbers are upright, facing you.
// Take the plug and orient it so that the arrow points down, facing you.
// Starting with the hole with the largest number in front of it, insert the small end of the plug into the hole.
// If you can insert and remove the small end of the plug from the hole without much force, then try again with the hole with the next smaller number.
// Repeat step 5 until you have found the hole with the smallest number that the plug fits into without much force.
// The correct hole should hold the plug when the long block is turned upside-down.
// The number in front of that hole will indicate the `$slop` value that is ideal for your printer.
// Remember to set that slop value in your scripts after you include the BOSL2 library: ie: `$slop = 0.15;`
// .
// Note that the `$slop` value may be different using different materials even on the same printer.
// Example(3D,Med): Slop Calibration Part.
// min_slop = 0.00;
// slop_step = 0.05;
// holes = 8;
// holesize = [15,15,15];
// height = 20;
// gap = 5;
// l = holes * (holesize.x + gap) + gap;
// w = holesize.y + 2*gap;
// h = holesize.z + 5;
// diff("holes")
// cuboid([l, w, h], anchor=BOT) {
// for (i=[0:holes-1]) {
// right((i-holes/2+0.5)*(holesize.x+gap)) {
// s = min_slop + slop_step * i;
// tag("holes") {
// cuboid([holesize.x + 2*s, holesize.y + 2*s, h+0.2]);
// fwd(w/2-1) xrot(90) linear_extrude(1.1) {
// text(
// text=format_fixed(s,2),
// size=0.4*holesize.x,
// halign="center",
// valign="center"
// );
// }
// }
// }
// }
// }
// back(holesize.y*2.5) {
// difference() {
// union() {
// cuboid([holesize.x+10, holesize.y+10, 15], anchor=BOT);
// cuboid([holesize.x, holesize.y, 15+holesize.z], anchor=BOT);
// }
// up(3) fwd((holesize.y+10)/2) {
// prismoid([holesize.x/2,1], [0,1], h=holesize.y-6);
// }
// }
// }
// Example(2D): Where to add `$slop` gaps.
// $slop = 0.2;
// difference() {
// square([20,12],center=true);
// back(3) square([10+2*$slop,11],center=true);
// }
// back(8) {
// rect([15,5],anchor=FWD);
// rect([10,8],anchor=BACK);
// }
// color("#000") {
// arrow_path = [[5.1,6.1], [6.0,7.1], [8,7.1], [10.5,10]];
// xflip_copy()
// stroke(arrow_path, width=0.3, endcap1="arrow2");
// xcopies(21) back(10.5) {
// back(1.8) text("$slop", size=1.5, halign="center");
// text("gap", size=1.5, halign="center");
// }
// }
// Function: get_slop()
// Synopsis: Returns the $slop value.
// Topics: Slop
// See Also: $slop
// Usage:
// slop = get_slop();
// Description:
// Returns the current $slop value, or the default value if the user did not set $slop.
// Always acess the `$slop` variable using this function.
function get_slop() = is_undef($slop) ? 0 : $slop;
// Constant: INCH
// Synopsis: A constant containing the number of millimeters in an inch. `25.4`
// Topics: Constants
// Description:
// The number of millimeters in an inch.
// Example(2D):
// square(2*INCH, center=true);
// Example(3D):
// cube([4,3,2.5]*INCH, center=true);
INCH = 25.4;
// Constant: IDENT
// Synopsis: A constant containing the 3D identity transformation matrix.
// SynTags: Mat
// Topics: Constants, Affine, Matrices, Transforms
// See Also: ident()
// Description: Identity transformation matrix for three-dimensional transforms. Equal to `ident(4)`.
IDENT=ident(4);
// Section: Directional Vectors
// Vectors useful for `rotate()`, `mirror()`, and `anchor` arguments for `cuboid()`, `cyl()`, etc.
// Constant: LEFT
// Synopsis: The left-wards (X-) direction vector constant `[-1,0,0]`.
// Topics: Constants, Vectors
// See Also: RIGHT, FRONT, BACK, UP, DOWN, CENTER
// Description: Vector pointing left. [-1,0,0]
// Example(3D): Usage with `anchor`
// cuboid(20, anchor=LEFT);
LEFT = [-1, 0, 0];
// Constant: RIGHT
// Synopsis: The right-wards (X+) direction vector constant `[1,0,0]`.
// Topics: Constants, Vectors
// See Also: LEFT, FRONT, BACK, UP, DOWN, CENTER
// Description: Vector pointing right. [1,0,0]
// Example(3D): Usage with `anchor`
// cuboid(20, anchor=RIGHT);
RIGHT = [ 1, 0, 0];
// Constant: FRONT
// Aliases: FWD, FORWARD
// Synopsis: The front-wards (Y-) direction vector constant `[0,-1,0]`.
// Topics: Constants, Vectors
// See Also: LEFT, RIGHT, BACK, UP, DOWN, CENTER
// Description: Vector pointing forward. [0,-1,0]
// Example(3D): Usage with `anchor`
// cuboid(20, anchor=FRONT);
FRONT = [ 0, -1, 0];
FWD = FRONT;
FORWARD = FRONT;
// Constant: BACK
// Synopsis: The backwards (Y+) direction vector constant `[0,1,0]`.
// Topics: Constants, Vectors
// See Also: LEFT, RIGHT, FRONT, UP, DOWN, CENTER
// Description: Vector pointing back. [0,1,0]
// Example(3D): Usage with `anchor`
// cuboid(20, anchor=BACK);
BACK = [ 0, 1, 0];
// Constant: BOTTOM
// Aliases: BOT, DOWN
// Synopsis: The down-wards (Z-) direction vector constant `[0,0,-1]`.
// Topics: Constants, Vectors
// See Also: LEFT, RIGHT, FRONT, BACK, UP, CENTER
// Description: Vector pointing down. [0,0,-1]
// Example(3D): Usage with `anchor`
// cuboid(20, anchor=BOTTOM);
BOTTOM = [ 0, 0, -1];
BOT = BOTTOM;
DOWN = BOTTOM;
// Constant: TOP
// Aliases: UP
// Synopsis: The top-wards (Z+) direction vector constant `[0,0,1]`.
// Topics: Constants, Vectors
// See Also: LEFT, RIGHT, FRONT, BACK, DOWN, CENTER
// Description: Vector pointing up. [0,0,1]
// Example(3D): Usage with `anchor`
// cuboid(20, anchor=TOP);
TOP = [ 0, 0, 1];
UP = TOP;
// Constant: CENTER
// Aliases: CTR, CENTRE
// Synopsis: The center vector constant `[0,0,0]`.
// Topics: Constants, Vectors
// See Also: LEFT, RIGHT, FRONT, BACK, UP, DOWN
// Description: Zero vector. Centered. [0,0,0]
// Example(3D): Usage with `anchor`
// cuboid(20, anchor=CENTER);
CENTER = [ 0, 0, 0]; // Centered zero vector.
CTR = CENTER;
CENTRE = CENTER;
// Function: EDGE()
// Synopsis: Named edge anchor constants
// Topics: Constants, Attachment
// Usage:
// EDGE(i)
// EDGE(direction,i)
// Description:
// A shorthand for the named anchors "edge0", "top_edge0", "bot_edge0", etc.
// Use `EDGE(i)` to get "edge<i>". Use `EDGE(TOP,i)` to get "top_edge<i>" and
// use `EDGE(BOT,i)` to get "bot_edge(i)". You can also use
// `EDGE(CTR,i)` to get "edge<i>" and you can replace TOP or BOT with simply 1 or -1.
function EDGE(a,b) =
is_undef(b) ? str("edge",a)
: assert(in_list(a,[TOP,BOT,CTR,1,0,-1]),str("Invalid direction: ",a))
let(
choices=["bot_","","top_"],
ind=is_vector(a) ? a.z : a
)
str(choices[ind+1],"edge",b);
// Function: FACE()
// Synopsis: Named face anchor constants
// Topics: Constants, Attachment
// Usage:
// FACE(i)
// Description:
// A shorthand for the named anchors "face0", "face1", etc.
function FACE(i) = str("face",i);
// Section: Line specifiers
// Used by functions in geometry.scad for specifying whether two points
// are treated as an unbounded line, a ray with one endpoint, or a segment
// with two endpoints.
// Constant: SEGMENT
// Synopsis: A constant for specifying a line segment in various geometry.scad functions. `[true,true]`
// Topics: Constants, Lines
// See Also: RAY, LINE
// Description: Treat a line as a segment. [true, true]
// Example: Usage with line_intersection:
// line1 = 10*[[9, 4], [5, 7]];
// line2 = 10*[[2, 3], [6, 5]];
// isect = line_intersection(line1, line2, SEGMENT, SEGMENT);
SEGMENT = [true,true];
// Constant: RAY
// Synopsis: A constant for specifying a ray line in various geometry.scad functions. `[true,false]`
// Topics: Constants, Lines
// See Also: SEGMENT, LINE
// Description: Treat a line as a ray, based at the first point. [true, false]
// Example: Usage with line_intersection:
// line = [[-30,0],[30,30]];
// pt = [40,25];
// closest = line_closest_point(line,pt,RAY);
RAY = [true, false];
// Constant: LINE
// Synopsis: A constant for specifying an unbounded line in various geometry.scad functions. `[false,false]`
// Topics: Constants, Lines
// See Also: RAY, SEGMENT
// Description: Treat a line as an unbounded line. [false, false]
// Example: Usage with line_intersection:
// line1 = 10*[[9, 4], [5, 7]];
// line2 = 10*[[2, 3], [6, 5]];
// isect = line_intersection(line1, line2, LINE, SEGMENT);
LINE = [false, false];
// vim: expandtab tabstop=4 shiftwidth=4 softtabstop=4 nowrap