addPoints.js

Area: Geometry

Subdivides every selected polycurve by inserting a new point at the midpoint of each bezier. It splits each segment with bez.getParamAtLength(bez.length * 0.5) and bez.split(t), rebuilds the curve with CurveBuilder, and writes it back through DocumentCommand.createSetPolyCurveNodeCurves. Demonstrates reading and rewriting curve geometry rather than just transforms.

Source: addPoints.js

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Example scripts

addPoints.js

Download addPoints.js

addPoints.js

/*
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Copyright (c) 2026, Canva Pty Ltd.

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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

'use strict';

const { Document } = require('/document.js');
const { DocumentCommand, CompoundCommandBuilder } = require('/commands.js');
const { CurveBuilder, PolyCurve } = require('/geometry.js');

const doc = Document.current;

function createNewCurve(curve) {
    const builder = CurveBuilder.create();
    const firstPoint = curve.beziers.first?.start;
    if (!firstPoint)
        return;
    builder.begin(firstPoint);
    for (const bez of curve.beziers) {
        const t = bez.getParamAtLength(bez.length * 0.5);
        const curves = bez.split(t);
        builder.addBezierXY(curves.left.c1.x, curves.left.c1.y, curves.left.c2.x, curves.left.c2.y, curves.left.end.x, curves.left.end.y);
        builder.addBezierXY(curves.right.c1.x, curves.right.c1.y, curves.right.c2.x, curves.right.c2.y, curves.right.end.x, curves.right.end.y);
    }
    return builder.createCurve();
}

function createNewPolyCurve(polyCurve) {
    const newPolyCurve = PolyCurve.create();
    for (const curve of polyCurve) {
        const newCurve = createNewCurve(curve);
        if (newCurve) {
            newPolyCurve.addCurve(newCurve);
        }
    }
    return newPolyCurve;
}

function addPoints(polyCurveNodes) {
    const cmds = [];
    for (const polyCurveNode of polyCurveNodes) {
        const newPoly = createNewPolyCurve(polyCurveNode.polyCurve);
        if (newPoly.curveCount > 0) {
            cmds.push(DocumentCommand.createSetCurves(polyCurveNode.curvesInterface, newPoly));
        }
    }

    if (cmds.length == 0)
        return;
    if (cmds.length == 1)
        doc.executeCommand(cmds[0]);
    else {
        const builder = CompoundCommandBuilder.create();
        for (const cmd of cmds) {
            builder.addCommand(cmd);
        }
        doc.executeCommand(builder.createCommand());
    }
}

function main() {
    if (!doc) {
        alert("This script requires an open document");
        return;
    }
    const nodes = doc.selection.nodes.filter(node => node.isPolyCurveNode);
    if (nodes.isEmpty) {
        alert("Select some curves");
        return;
    }
    addPoints(nodes);
}

module.exports.main = main;