58 lines
1.7 KiB
JavaScript
58 lines
1.7 KiB
JavaScript
import array from "./array.js";
|
|
import constant from "./constant.js";
|
|
import curveLinear from "./curve/linear.js";
|
|
import {withPath} from "./path.js";
|
|
import {x as pointX, y as pointY} from "./point.js";
|
|
|
|
export default function(x, y) {
|
|
var defined = constant(true),
|
|
context = null,
|
|
curve = curveLinear,
|
|
output = null,
|
|
path = withPath(line);
|
|
|
|
x = typeof x === "function" ? x : (x === undefined) ? pointX : constant(x);
|
|
y = typeof y === "function" ? y : (y === undefined) ? pointY : constant(y);
|
|
|
|
function line(data) {
|
|
var i,
|
|
n = (data = array(data)).length,
|
|
d,
|
|
defined0 = false,
|
|
buffer;
|
|
|
|
if (context == null) output = curve(buffer = path());
|
|
|
|
for (i = 0; i <= n; ++i) {
|
|
if (!(i < n && defined(d = data[i], i, data)) === defined0) {
|
|
if (defined0 = !defined0) output.lineStart();
|
|
else output.lineEnd();
|
|
}
|
|
if (defined0) output.point(+x(d, i, data), +y(d, i, data));
|
|
}
|
|
|
|
if (buffer) return output = null, buffer + "" || null;
|
|
}
|
|
|
|
line.x = function(_) {
|
|
return arguments.length ? (x = typeof _ === "function" ? _ : constant(+_), line) : x;
|
|
};
|
|
|
|
line.y = function(_) {
|
|
return arguments.length ? (y = typeof _ === "function" ? _ : constant(+_), line) : y;
|
|
};
|
|
|
|
line.defined = function(_) {
|
|
return arguments.length ? (defined = typeof _ === "function" ? _ : constant(!!_), line) : defined;
|
|
};
|
|
|
|
line.curve = function(_) {
|
|
return arguments.length ? (curve = _, context != null && (output = curve(context)), line) : curve;
|
|
};
|
|
|
|
line.context = function(_) {
|
|
return arguments.length ? (_ == null ? context = output = null : output = curve(context = _), line) : context;
|
|
};
|
|
|
|
return line;
|
|
}
|