MCAD-Library/2Dshapes.scad

/*
 *  OpenSCAD 2D Shapes Library (www.openscad.org)
 *  Copyright (C) 2012 Peter Uithoven
 *
 *  License: LGPL 2.1 or later

 *  2D Shapes
 *  ngon(sides, radius, center=false);
 *  complexRoundSquare(size,rads1=[0,0], rads2=[0,0], rads3=[0,0], rads4=[0,0], center=true)
 *  roundedSquare(pos=[10,10],r=2)
 *  ellipsePart(width,height,numQuarters)
 *  donutSlice(innerSize,outerSize, start_angle, end_angle)
 *  pieSlice(size, start_angle, end_angle) //size in radius(es)
 *  ellipse(width, height) {
*/

// Examples - (layouts.scad is required for examples)
// example2DShapes(); use <layouts.scad>;

module example2DShapes() {
    grid(105,105,true,4)
    {
        // ellipse
        ellipse(50,75);

        // part of ellipse (a number of quarters)
        ellipsePart(50,75,3);
        ellipsePart(50,75,2);
        ellipsePart(50,75,1);

        // complexRoundSquare examples
        complexRoundSquare([75,100],[20,10],[20,10],[20,10],[20,10]);
        complexRoundSquare([75,100],[0,0],[0,0],[30,50],[20,10]);
        complexRoundSquare([50,50],[10,20],[10,20],[10,20],[10,20],false);
        complexRoundSquare([100,100]);
        complexRoundSquare([100,100],rads1=[20,20],rads3=[20,20]);

        // pie slice
        pieSlice(50,0,10);
        pieSlice(50,45,190);
        pieSlice([50,20],180,270);

        // donut slice
        donutSlice(20,50,0,350);
        donutSlice(30,50,190,270);
        donutSlice([40,22],[50,30],180,270);
        donutSlice([50,20],50,180,270);
        donutSlice([20,30],[50,40],0,270);
    }
}
// end examples ----------------------

module complexRoundSquare(
    size, // Size
    rads1=[0,0], // Top left radius
    rads2=[0,0], // Top right radius
    rads3=[0,0], // Bottom right radius
    rads4=[0,0], // Bottom left radius
    center=true // center
) {
    width = size[0];
    height = size[1];
    // %square(size=[width, height],center=true);
    x1 = 0-width/2+rads1[0];
    y1 = 0-height/2+rads1[1];
    x2 = width/2-rads2[0];
    y2 = 0-height/2+rads2[1];
    x3 = width/2-rads3[0];
    y3 = height/2-rads3[1];
    x4 = 0-width/2+rads4[0];
    y4 = height/2-rads4[1];

    scs = 0.1; // straight corner size

    x = (center)? 0: width/2;
    y = (center)? 0: height/2;

    translate([x,y,0])
    hull()
    {
        // top left
        if(rads1[0] > 0 && rads1[1] > 0)
            translate([x1,y1])
            mirror([1,0])
            ellipsePart(rads1[0]*2,rads1[1]*2,1);
        else
            translate([x1,y1])
            square(size=[scs, scs]);

        // top right
        if(rads2[0] > 0 && rads2[1] > 0)
            translate([x2,y2])
            ellipsePart(rads2[0]*2,rads2[1]*2,1);
        else
            translate([width/2-scs,0-height/2])
            square(size=[scs, scs]);

        // bottom right
        if(rads3[0] > 0 && rads3[1] > 0)
            translate([x3,y3])
            mirror([0,1])
            ellipsePart(rads3[0]*2,rads3[1]*2,1);
        else
            translate([width/2-scs,height/2-scs])
            square(size=[scs, scs]);

        // bottom left
        if(rads4[0] > 0 && rads4[1] > 0)
            translate([x4,y4])
            rotate([0,0,-180])
            ellipsePart(rads4[0]*2,rads4[1]*2,1);
        else
            #translate([x4,height/2-scs])
            square(size=[scs, scs]);
    }
}

module roundedSquare(pos=[10,10],r=2) {
    minkowski()
    {
        square([pos[0]-r*2,pos[1]-r*2],center=true);


        circle(r=r);
    }
}

// round shapes
// The orientation might change with the implementation of circle...
module ngon(sides, radius, center=false) {
    rotate([0, 0, 360/sides/2])
    circle(r=radius, $fn=sides, center=center);
}

module ellipsePart(width,height,numQuarters) {
    o = 1; //slight overlap to fix a bug
    difference()
    {
        ellipse(width,height);

        if(numQuarters <= 3)
            translate([0-width/2-o,0-height/2-o,0])
            square([width/2+o,height/2+o]);
        if(numQuarters <= 2)
            translate([0-width/2-o,-o,0])
            square([width/2+o,height/2+o*2]);
        if(numQuarters < 2)
            translate([-o,0,0])
            square([width/2+o*2,height/2+o]);
    }
}

module donutSlice(innerSize,outerSize, start_angle, end_angle) {
    difference()
    {
        pieSlice(outerSize, start_angle, end_angle);

        if(is_list(innerSize) && len(innerSize) > 1)
             ellipse(innerSize[0]*2,innerSize[1]*2);
        else
            circle(innerSize);
    }
}

module pieSlice(size, start_angle, end_angle) { //size in radius(es)
    rx = (is_list(size) && len(size) > 1)? size[0] : size;
    ry = (is_list(size) && len(size) > 1)? size[1] : size;
    trx = rx* sqrt(2) + 1;
    try = ry* sqrt(2) + 1;
    a0 = (4 * start_angle + 0 * end_angle) / 4;
    a1 = (3 * start_angle + 1 * end_angle) / 4;
    a2 = (2 * start_angle + 2 * end_angle) / 4;
    a3 = (1 * start_angle + 3 * end_angle) / 4;
    a4 = (0 * start_angle + 4 * end_angle) / 4;

    if(end_angle > start_angle)
        intersection() {
        if(is_list(size) && len(size) > 1)
            ellipse(rx*2,ry*2);
        else
            circle(rx);
        polygon([
            [0,0],
            [trx * cos(a0), try * sin(a0)],
            [trx * cos(a1), try * sin(a1)],
            [trx * cos(a2), try * sin(a2)],
            [trx * cos(a3), try * sin(a3)],
            [trx * cos(a4), try * sin(a4)],
            [0,0]
        ]);
    }
}

module ellipse(width, height) {
    scale([1, height/width, 1])
    circle(r=width/2);
}