• 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 DOM 011

    Canvas controller ‘fit’ attribute; Cell positioning (mouse)

  • §

    Run code

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

    Scene setup

    let artefact = scrawl.library.artefact,
        stack = artefact.mystack,
        canvas = artefact.mycanvas;
  • §

    Resize the stack, and give it some CSS

    stack.set({
        width: 400,
        height: 400,
        css: {
            margin: '15px 0 0 0',
            border: '1px solid black',
            overflow: 'hidden',
            resize: 'both',
        },
        checkForResize: true,
    });
  • §

    A displayed canvas can have more than one hidden canvas. These additional ‘cells’ - which act much like traditional animation cels (see https://en.wikipedia.org/wiki/Cel) - will be copied onto the ‘base’ canvas before the it gets copied over to the displayed cell at the end of every display cycle.

    let cell = canvas.buildCell({
        name: 'mycell',
        width: '50%',
        height: '50%',
        startX: 'center',
        startY: 'center',
        handleX: 'center',
        handleY: 'center',
        roll: 12,
        scale: 1.2,
        backgroundColor: 'blue',
    });
  • §

    Scene animation

    Function to check whether mouse cursor is over the canvas element within the stack, and lock the element artefact accordingly

    let check = function () {
    
        let active = false,
            here = canvas.here,
            cell = scrawl.library.asset.mycell;
    
        return function () {
    
            if (here.baseActive !== active) {
    
                active = here.baseActive;
    
                cell.set({
                    lockTo: (active) ? 'mouse' : 'start',
                });
            }
        };
    }();
  • §

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

    const report = reportSpeed('#reportmessage');
  • §

    Create the Animation loop which will run the Display cycle. Note that we don’t have to define a target - useful for when we want to cascade through multiple stacks (which don’t themselves trigger canvas redraws, just canvas positioning) and multiple canvases

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

    User interaction

    For this demo we will suppress touchmove functionality over the canvas

    scrawl.addNativeListener(['touchmove'], (e) => {
    
        e.preventDefault();
        e.returnValue = false;
    
    }, stack.domElement);
  • §

    Event listeners

    scrawl.observeAndUpdate({
    
        event: ['input', 'change'],
        origin: '.controlItem',
    
        target: canvas,
    
        useNativeListener: true,
        preventDefault: true,
    
        updates: {
            fitselect: ['fit', 'raw'],
        },
    });
  • §

    Test to make sure Stack is listening for external changes in its dimensions, and that these changes are perculating down to the canvas and its base cell

    • Stack artefact’s checkForResize flag set to true, enabling the checks
    • Can resize Stack’s DOM element by dragging the lower right corner
    • Can also resize the element by using the width and height form controls - these controls then update the element’s style width and height via the event listeners below.
    • In both cases, the Stack artefact needs to check whether resizing has occurred and take action.
    document.querySelector('#width').addEventListener('input', (e) => {
  • §

    @ts-expect-error

        stack.domElement.style.width = `${e.target.value}px`;
    }, false);
    document.querySelector('#height').addEventListener('input', (e) => {
  • §

    @ts-expect-error

        stack.domElement.style.height = `${e.target.value}px`;
    }, false);
  • §

    Set the DOM input values @ts-expect-error

    document.querySelector('#fitselect').value = 'fill';
  • §

    @ts-expect-error

    document.querySelector('#width').value = '400';
  • §

    @ts-expect-error

    document.querySelector('#height').value = '400';
  • §

    Development and testing

    Dev tip 1: Scrawl-canvas doesn’t add a namespace object to the Javascript global object. To see what’s going on in the Scrawl-canvas library - where all relevant SC objects are held - console log it (in the code file, not directly in the browser console):

    console.log(scrawl.library);

    • doesn’t update in real time, but closing and opening the object in the console should reveal values at the point in time when it is reopened
    • In Chrome console (at least), the various objects in the library will be listed with their object type eg Stack, Canvas, Cell, etc

    If you only want to view a specific part of the library - for example, just artefacts - console log it out in the same way:

    console.log(scrawl.library.artefact);

    Dev tip 2: to see what’s going on in any hidden canvas, temporarily add it to the bottom of the page, or insert it wherever using appropriate DOM API functionality:

    document.body.appendChild(scrawl.library.cell[NAME].element);