You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
52 lines
1.4 KiB
52 lines
1.4 KiB
export function point(that, x, y) {
|
|
that._context.bezierCurveTo(
|
|
(2 * that._x0 + that._x1) / 3,
|
|
(2 * that._y0 + that._y1) / 3,
|
|
(that._x0 + 2 * that._x1) / 3,
|
|
(that._y0 + 2 * that._y1) / 3,
|
|
(that._x0 + 4 * that._x1 + x) / 6,
|
|
(that._y0 + 4 * that._y1 + y) / 6
|
|
);
|
|
}
|
|
|
|
export function Basis(context) {
|
|
this._context = context;
|
|
}
|
|
|
|
Basis.prototype = {
|
|
areaStart: function() {
|
|
this._line = 0;
|
|
},
|
|
areaEnd: function() {
|
|
this._line = NaN;
|
|
},
|
|
lineStart: function() {
|
|
this._x0 = this._x1 =
|
|
this._y0 = this._y1 = NaN;
|
|
this._point = 0;
|
|
},
|
|
lineEnd: function() {
|
|
switch (this._point) {
|
|
case 3: point(this, this._x1, this._y1); // proceed
|
|
case 2: this._context.lineTo(this._x1, this._y1); break;
|
|
}
|
|
if (this._line || (this._line !== 0 && this._point === 1)) this._context.closePath();
|
|
this._line = 1 - this._line;
|
|
},
|
|
point: function(x, y) {
|
|
x = +x, y = +y;
|
|
switch (this._point) {
|
|
case 0: this._point = 1; this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y); break;
|
|
case 1: this._point = 2; break;
|
|
case 2: this._point = 3; this._context.lineTo((5 * this._x0 + this._x1) / 6, (5 * this._y0 + this._y1) / 6); // proceed
|
|
default: point(this, x, y); break;
|
|
}
|
|
this._x0 = this._x1, this._x1 = x;
|
|
this._y0 = this._y1, this._y1 = y;
|
|
}
|
|
};
|
|
|
|
export default function(context) {
|
|
return new Basis(context);
|
|
}
|