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intersections

intersections(
name: str,..elements: elementsstr,samples: int,sort: nonefunction,ignore-marks: bool,
)

Calculates the intersections between multiple paths and creates one anchor per intersection point.

All resulting anchors will be named numerically, starting at 0. i.e., a call intersections("a", ...) will generate the anchors "a.0", "a.1", "a.2" to "a.n", depending of the number of intersections.

You can also use named elements:

You can calculate intersections with hidden elements by using hide.

CeTZ provides the following sorting functions:

  • sorting.points-by-distace(points, reference: (0, 0, 0))
  • sorting.points-by-angle(points, reference: (0, 0, 0))
intersections("i", {
  circle((0, 0))
  bezier((0,0), (3,0), (1,-1), (2,1))
  line((0,-1), (0,1))
  rect((1.5,-1),(2.5,1))
})
for-each-anchor("i", (name) => {
  circle("i." + name, radius: .1, fill: blue)
})
circle((0,0), name: "a")
rect((0,0), (1,1), name: "b")
intersections("i", "a", "b")
for-each-anchor("i", (name) => {
  circle("i." + name, radius: .1, fill: blue)
})

name:

str
​

Name to prepend to the generated anchors. (Not to be confused with other name arguments that allow the use of anchor coordinates.)

..elements:

elements or str
​

Elements and/or element names to calculate intersections with. Elements referred to by name are (unlike elements passed) not drawn by the intersections function!

samples:

int
​

Number of samples to use for non-linear path segments. A higher sample count can give more precise results but worse performance.

sort:

none or function
​

A function of the form (context, array<vector>) -> array<vector> that gets called with the list of intersection points.

ignore-marks:

bool
​

If true, ignore mark shapes.