bug in simple "substract()

[hrgdavor]

Initially reported at: hrgdavor/jscadui#142

code example shows a cylinder "c" and a cuboid with skew borders "d" with nonempty intersection:

const jscad = require('@jscad/modeling')
const { polygon } = jscad.primitives
const { cylinder } = jscad.primitives
const { translate, mirror, rotate } = require('@jscad/modeling').transforms
const { extrudeLinear } = require('@jscad/modeling').extrusions
const { subtract } = require('@jscad/modeling').booleans

const d1=86
const d2=87
const h=2

function main() {
  const p=polygon({points: [[0,0],[d1/2,0],[d2/2,h],[0,h]]})
  const e=extrudeLinear({height:d1},p)
  const et=translate([0,0,-d1/2],e)
  const P=[et,mirror({normal:[1,0,0]}, et)]
  const d=[P,rotate([0,Math.PI/2,0],P)]
  const c=translate([0,h/2,0],rotate([Math.PI/2,0,0],cylinder({height:2*h, radius:0.4*d1})))
  
  return [
    //d,c 
    subtract(d,c)
  ]
}

module.exports = { main }

Now subtracting "d" from "c" gives expected results:

But subtracting "c" from "d" does not result in the intended "d" with circular hole:

Until now "subtract()" was very reliable over the past years ...

[Hermann-SW]

From the other ticket this workaround seems to be good to have here as well:

Just found a workaround, while "subtract(d,c)" does not work, "subtract(hull(d),c)" works!