• Jump To … +
    ./demo/canvas-001.js ./demo/canvas-002.js ./demo/canvas-003.js ./demo/canvas-004.js ./demo/canvas-005.js ./demo/canvas-006.js ./demo/canvas-007.js ./demo/canvas-008.js ./demo/canvas-009.js ./demo/canvas-010.js ./demo/canvas-011.js ./demo/canvas-012.js ./demo/canvas-013.js ./demo/canvas-014.js ./demo/canvas-015.js ./demo/canvas-015a.js ./demo/canvas-016.js ./demo/canvas-017.js ./demo/canvas-018.js ./demo/canvas-019.js ./demo/canvas-019a.js ./demo/canvas-020.js ./demo/canvas-021.js ./demo/canvas-022.js ./demo/canvas-023.js ./demo/canvas-024.js ./demo/canvas-025.js ./demo/canvas-026.js ./demo/canvas-027.js ./demo/canvas-028.js ./demo/canvas-029.js ./demo/canvas-030.js ./demo/canvas-031.js ./demo/canvas-032.js ./demo/canvas-033.js ./demo/canvas-034.js ./demo/canvas-035.js ./demo/canvas-036.js ./demo/canvas-037.js ./demo/canvas-038.js ./demo/canvas-039.js ./demo/canvas-040.js ./demo/canvas-041.js ./demo/canvas-042.js ./demo/canvas-043.js ./demo/canvas-044.js ./demo/canvas-045.js ./demo/canvas-046.js ./demo/canvas-047.js ./demo/canvas-048.js ./demo/canvas-049.js ./demo/canvas-050.js ./demo/canvas-051.js ./demo/canvas-052.js ./demo/canvas-053.js ./demo/canvas-054.js ./demo/canvas-055.js ./demo/canvas-056.js ./demo/canvas-057.js ./demo/canvas-058.js ./demo/canvas-059.js ./demo/canvas-060.js ./demo/canvas-061.js ./demo/canvas-062.js ./demo/canvas-063.js ./demo/canvas-064.js ./demo/core-001.js ./demo/delaunator-001.js ./demo/delaunator-002.js ./demo/dom-001.js ./demo/dom-002.js ./demo/dom-003.js ./demo/dom-004.js ./demo/dom-005.js ./demo/dom-006.js ./demo/dom-007.js ./demo/dom-008.js ./demo/dom-009.js ./demo/dom-010.js ./demo/dom-011.js ./demo/dom-012.js ./demo/dom-013.js ./demo/dom-015.js ./demo/dom-016.js ./demo/filters-001.js ./demo/filters-002.js ./demo/filters-002a.js ./demo/filters-003.js ./demo/filters-004.js ./demo/filters-005.js ./demo/filters-006.js ./demo/filters-007.js ./demo/filters-008.js ./demo/filters-009.js ./demo/filters-010.js ./demo/filters-011.js ./demo/filters-012.js ./demo/filters-013.js ./demo/filters-014.js ./demo/filters-015.js ./demo/filters-016.js ./demo/filters-017.js ./demo/filters-018.js ./demo/filters-019.js ./demo/filters-020.js ./demo/filters-021.js ./demo/filters-022.js ./demo/filters-023.js ./demo/filters-024.js ./demo/filters-025.js ./demo/filters-026.js ./demo/filters-027.js ./demo/filters-101.js ./demo/filters-102.js ./demo/filters-103.js ./demo/filters-104.js ./demo/filters-105.js ./demo/filters-501.js ./demo/filters-502.js ./demo/filters-503.js ./demo/filters-504.js ./demo/filters-505.js ./demo/mediapipe-001.js ./demo/mediapipe-002.js ./demo/mediapipe-003.js ./demo/modules-001.js ./demo/modules-002.js ./demo/modules-003.js ./demo/modules-004.js ./demo/modules-005.js ./demo/packets-001.js ./demo/packets-002.js ./demo/particles-001.js ./demo/particles-002.js ./demo/particles-003.js ./demo/particles-004.js ./demo/particles-005.js ./demo/particles-006.js ./demo/particles-007.js ./demo/particles-008.js ./demo/particles-009.js ./demo/particles-010.js ./demo/particles-011.js ./demo/particles-012.js ./demo/particles-013.js ./demo/particles-014.js ./demo/particles-015.js ./demo/particles-016.js ./demo/rapier-001.js ./demo/snippets-001.js ./demo/snippets-002.js ./demo/snippets-003.js ./demo/snippets-004.js ./demo/snippets-005.js ./demo/snippets-006.js ./demo/temp-000.js ./demo/temp-001.js ./demo/temp-001a.js ./demo/temp-002.js ./demo/temp-003.js ./demo/temp-004.js ./demo/temp-005.js ./demo/temp-006.js ./demo/temp-007.js ./demo/temp-008.js ./demo/temp-009.js ./demo/temp-010.js ./demo/temp-011.js ./demo/temp-012.js ./demo/temp-013.js ./demo/temp-014.js ./demo/temp-015.js ./demo/temp-016.js ./demo/temp-017.js ./demo/temp-018.js ./demo/temp-018a.js ./demo/temp-019.js ./demo/temp-020.js ./demo/temp-021.js ./demo/temp-022.js ./demo/temp-023.js ./demo/temp-024.js ./demo/temp-025.js ./demo/temp-026.js ./demo/temp-027.js ./demo/temp-028.js ./demo/temp-029.js ./demo/temp-030.js ./demo/temp-031.js ./demo/temp-032.js ./demo/temp-033.js ./demo/temp-034.js ./demo/temp-035.js ./demo/temp-036.js ./demo/temp-037.js ./demo/temp-100.js ./demo/temp-101.js ./demo/temp-102.js ./demo/temp-103.js ./demo/temp-104.js ./demo/temp-200.js ./demo/temp-201.js ./demo/temp-301.js ./demo/temp-inkscapeSvgFilters.js ./demo/temp-lottie.js ./demo/tensorflow-001.js ./demo/tensorflow-002.js ./demo/utilities.js
  • §

    Demo Canvas 030

    Polyline entity functionality

    • Note that the Polyline entity remains experimental technology and may be subject to breaking changes in future minor updates
  • §

    Run code

    import * as scrawl from '../source/scrawl.js'
    
    import { reportSpeed, killPolylineArtefact } from './utilities.js';
  • §

    Scene setup

    let canvas = scrawl.library.artefact.mycanvas;
  • §

    Build some coordinate arrays …

    let absoluteCoords = [[100, 200], [200, 400], [300, 300], [400, 400], [500, 200], [240, 100]];
    
    let relativeCoords = [['50%', 'center'], ['40%', '10%'], ['20%', '40%'], ['25%', '80%'], ['70%', '75%'], ['85%', '60%']];
  • §

    … And a third coordinate array using Wheel entitys

    absoluteCoords.forEach((item, index) => {
    
        const [x, y] = item;
    
        scrawl.makeWheel({
    
            name: `pin-${index}`,
    
            startX: x,
            startY: y,
    
            radius: 20,
    
            handleX: 'center',
            handleY: 'center',
    
            shadowColor: 'black',
            fillStyle: 'darkgreen',
            method: 'fill',
        });
    });
    
    let pivotCoords = ['pin-0', 'pin-1', 'pin-2', 'pin-3', 'pin-4', 'pin-5'];
  • §

    Add another Wheel entity to act as a (potential) pivot for the Polyline

    scrawl.makeWheel({
    
        name: 'pivot-wheel',
    
        start: [50, 50],
    
        radius: 20,
    
        handleX: 'center',
        handleY: 'center',
    
        shadowColor: 'black',
        fillStyle: 'darkred',
        method: 'fill',
    });
  • §

    Define the Polyline entity

    let myline = scrawl.makePolyline({
    
        name: 'my-polyline',
  • §

    The pins attribute takes an array with elements which are:

    • [x, y] coordinate arrays, where values can be absolute (Numbers) and/or relative (String%) values
    • Artefact objects, or their name-String values
    • (set function will also accept an object with attributes: index, x, y - to be used by tweens) pins: absoluteCoords,
        pins: absoluteCoords,
  • §

    Tension gives us the curviness of the line:

    • 0 - straight lines connecting the pins
    • 0.4ish - reasonable looking curves
    • 1 - exaggerated curves
    • negative values - add loops at the pins
        tension: 0,
  • §

    Whether to connect all the pins (true), or run from first to last pin only (false)

        closed: false,
  • §

    The starting position is the top left corner of the box which tightly encloses the Shape - regardless of the positions of any artefacts which may be used as pins. Handles and offsets should work as expected

    • This functionality changes when the mapToPins flag is set; now the start coordinate maps directly to the first coordinate supplied in the pins array. Handle and offset values can no longer be relied on.
        startX: 0,
        startY: 0,
  • §

    The precision attribute determines the accuracy for positioning artefacts on the path when they have set their constantPathSpeed flag to true

    • Natural path speed leads to slower progression around tight corners; constant path speed attempts to even out these variations across the length of the path.
    • The default precision value is 10; decreasing the value increases the positioning accuracy. The more accurate the positioning, the greater the computational (and memory) burden.
        precision: 0.05,
    
        pivot: 'pivot-wheel',
        lockTo: 'start',
    
        mapToPins: false,
    
        strokeStyle: 'orange',
        lineWidth: 6,
    
        lineCap: 'round',
        lineJoin: 'round',
    
        shadowColor: 'black',
    
        method: 'draw',
  • §

    Note: the bounding box dimensions reflect the minimum/maximum coordinates of all the pins used to construct the shape. It will only reflect the actual shape of the Shape when useAsPath attribute is set to true

        showBoundingBox: true,
  • §

    Note: when using a Polyline entity as a pivot for other artefacts, set the useAsPath flag to true

    • It generates more accurate results - particularly when the Polyline is flipped, rolled and/or scaled, and when underlying pins (particularly when those pins are artefacts) update their coordinates.
        useAsPath: true,
    });
  • §

    Add some Block entitys which will pivot to our Polyline entity

    absoluteCoords.forEach((item, index) => {
    
        scrawl.makeBlock({
    
            name: `block-${index}`,
    
            width: 20,
            height: 20,
    
            pivot: 'my-polyline',
            pivotPin: index,
            lockTo: 'pivot',
    
            handleX: 'center',
            handleY: 'center',
    
            roll: 45,
    
            fillStyle: 'lightblue',
            strokeStyle: 'yellow',
            lineWidth: 3,
            method: 'fillThenDraw',
        });
    });
  • §

    Testing natural vs constant speeds along the path

    for (let i = 0; i < 10; i++) {
    
        scrawl.makeWheel({
    
            name: `normal-ball-${i}`,
            order: 2,
    
            radius: 10,
            fillStyle: 'lightgreen',
            strokeStyle: 'red',
            method: 'fillThenDraw',
    
            handle: ['center', 'center'],
    
            path: 'my-polyline',
            pathPosition: i / 100,
            lockTo: 'path',
            
            delta: {
                pathPosition: 0.001,
            },
    
        }).clone({
    
            name: `constant-ball-${i}`,
            fillStyle: 'yellow',
            strokeStyle :'blue',
    
            pathPosition: (i / 100) + 0.5,
    
            constantSpeedAlongPath: true,
        });
    }
  • §

    User interaction

    Create the drag-and-drop zone

    scrawl.makeDragZone({
        zone: canvas,
        collisionGroup: canvas.base.name,
        endOn: ['up', 'leave'],
    
        updateOnStart: {
            shadowBlur: 6,
            shadowOffsetX: 3,
            shadowOffsetY: 3,
        },
    
        updateOnEnd: {
            shadowBlur: 0,
            shadowOffsetX: 0,
            shadowOffsetY: 0,
        },
    
        preventTouchDefaultWhenDragging: true,
    });
  • §

    Scene animation

    Function to display frames-per-second data, and other information relevant to the demo

    const report = reportSpeed('#reportmessage', function () {
        return `Bounding box: ${myline.getBoundingBox().join(', ')}`;
    });
  • §

    Create the Display cycle animation

    scrawl.makeRender({
    
        name: 'demo-animation',
        target: canvas,
        afterShow: report,
    });
  • §

    More user interaction

    scrawl.observeAndUpdate({
    
        event: ['input', 'change'],
        origin: '.controlItem',
    
        target: myline,
    
        useNativeListener: true,
        preventDefault: true,
    
        updates: {
    
            tension: ['tension', 'float'],
            pivot: ['lockTo', 'raw'],
            closed: ['closed', 'boolean'],
            path: ['useAsPath', 'boolean'],
            map: ['mapToPins', 'boolean'],
            reverse: ['flipReverse', 'boolean'],
            upend: ['flipUpend', 'boolean'],
            roll: ['roll', 'float'],
            scale: ['scale', 'float'],
        },
    });
  • §

    Change the coordinate array used by the Polyline

    let updatePins = (e) => {
    
        e.preventDefault();
        e.returnValue = false;
    
        let val = e.target.value;
    
        if (val === 'absolute') myline.set({ pins: absoluteCoords });
        else if (val === 'relative') myline.set({ pins: relativeCoords });
        else if (val === 'artefacts') myline.set({ pins: pivotCoords });
    };
    scrawl.addNativeListener(['input', 'change'], updatePins, '#pins');
  • §

    Setup form @ts-expect-error

    document.querySelector('#tension').value = 0;
  • §

    @ts-expect-error

    document.querySelector('#pivot').value = 'start';
  • §

    @ts-expect-error

    document.querySelector('#closed').value = 0;
  • §

    @ts-expect-error

    document.querySelector('#path').value = 1;
  • §

    @ts-expect-error

    document.querySelector('#map').value = 0;
  • §

    @ts-expect-error

    document.querySelector('#pins').value = 'absolute';
  • §

    @ts-expect-error

    document.querySelector('#reverse').value = 0;
  • §

    @ts-expect-error

    document.querySelector('#upend').value = 0;
  • §

    @ts-expect-error

    document.querySelector('#roll').value = 0;
  • §

    @ts-expect-error

    document.querySelector('#scale').value = 1;
  • §

    Development and testing

    console.log(scrawl.library);
    
    console.log('Performing tests ...');
    
    killPolylineArtefact(canvas, 'pin-2', 3000, myline, () => myline.updatePinAt('pin-2', 2));