KeyV2/src/dishes/cylindrical.scad

20 lines
781 B
OpenSCAD

module cylindrical_dish(width, height, depth, inverted){
// .5 has problems starting around 3u
$fa=.25;
/* we do some funky math here
* basically you want to have the dish "dig in" to the keycap x millimeters
* in order to do that you have to solve a small (2d) system of equations
* where the chord of the spherical cross section of the dish is
* the width of the keycap.
*/
// the distance you have to move the dish so it digs in depth millimeters
chord_length = (pow(width, 2) - 4 * pow(depth, 2)) / (8 * depth);
//the radius of the dish
rad = (pow(width, 2) + 4 * pow(depth, 2)) / (8 * depth);
direction = inverted ? -1 : 1;
translate([0,0, chord_length * direction]){
rotate([90, 0, 0]) cylinder(h=height + 20, r=rad, center=true);
}
}