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  ./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-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/dom-017.js ./demo/dom-018.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-028.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/modules-006.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/tensorflow-001.js ./demo/tensorflow-002.js ./demo/utilities.js

- §

  # Demo Canvas 029

  Phrase entitys and gradients

- §

  Run code

      import * as scrawl from '../source/scrawl.js'

      import { reportSpeed } from './utilities.js';

- §

  #### Scene setup

  Get a handle to the Canvas wrapper

      const canvas = scrawl.library.artefact.mycanvas;

- §

  Namespacing boilerplate

      const namespace = 'demo';
      const name = (n) => `${namespace}-${n}`;

- §

  Create Gradient

      const mygradient = scrawl.makeGradient({

          name: name('gradient-1'),

          endX: '100%',

          paletteStart: 10,
          paletteEnd: 990,

          delta: {
              paletteStart: -1,
              paletteEnd: -1,
          },

          cyclePalette: true,
          animateByDelta: true,

          colors: [
              [0, 'black'],
              [19, 'red'],
              [499, 'black'],
              [549, 'yellow'],
              [599, 'black'],
              [979, 'aqua'],
              [999, 'black'],
          ],
      });

      scrawl.makeQuadratic({

          name: name('my-quad'),

          startX: '30%',
          startY: '98%',

          controlX: '60%',
          controlY: '78%',

          endX: '90%',
          endY: '98%',

          method: 'draw',

          useAsPath: true,
      });

- §

  Create Phrase entitys

      scrawl.makePhrase({

          name: name('test-phrase-1'),
          order: 1,

          text: 'Test phrase',
          font: 'bold 46px Garamond, serif',

          startX: '5%',
          startY: '5%',

          fillStyle: name('gradient-1'),

      }).clone({

          name: name('test-phrase-2'),

          width: '40%',

          startX: '50%',

          justify: 'left',

      }).clone({

          name: name('test-phrase-3'),

          startY: '30%',

          flipUpend: true,

      }).clone({

          name: name('test-phrase-4'),

          startX: '5%',

          lockFillStyleToEntity: true,

      }).clone({

          name: name('test-phrase-5'),

          font: '46px cursive',

          roll: 90,
          scale: 0.8,

          startX: '50%',
          startY: '33%',

          width: 'auto',

      }).clone({

          name: name('test-phrase-6'),

          startX: '43%',
          startY: '75%',

          lockFillStyleToEntity: false,

          flipReverse: true,

      }).clone({

          name: name('test-phrase-7'),

- §

  Test to see if we can load a webfont from a remote server and see it show up in the canvas element

  - If the test fails then the phrase will display as 46pt sans-serif

          font: '46px "Mountains of Christmas"',

          startX: '0%',
          startY: '10%',

          flipReverse: false,
          flipUpend: false,

          roll: 0,
          scale: 1,

          textPath: name('my-quad'),

          handleY: '50%',

          lockFillStyleToEntity: true,

          delta: {
              textPathPosition: -0.005,
          }
      });

      scrawl.makePhrase({

          name: name('test-phrase-8'),

          text: 'Lorem ipsum har varit standard ända sedan 1500-talet, när-en-okänd-boksättare-tog att antal bokstäver och blandade dem för att göra ett provexemplar av en bok.',

          font: '18px Garamond, serif',
          lineHeight: 1,

          width: '35%',

          startX: '5%',
          startY: '35%',

          fillStyle: name('gradient-1'),

      }).clone({

          name: name('test-phrase-9'),

          startX: '58%',
          scale: 0.8,
          letterSpacing: 3,

          lockFillStyleToEntity: true,
      });

      scrawl.makeBlock({

          name: name('top-block'),

          width: '100%',
          height: 10,

          fillStyle: name('gradient-1'),

          order: 0,

      }).clone({

          name: name('left-block'),

          height: '100%',
          width: 10,
      });

      const myGroup = scrawl.makeGroup({

          name: name('text-group'),

      }).addArtefacts(
          name('test-phrase-1'),
          name('test-phrase-2'),
          name('test-phrase-3'),
          name('test-phrase-4'),
          name('test-phrase-5'),
          name('test-phrase-6'),
          name('test-phrase-7'),
          name('test-phrase-8'),
          name('test-phrase-9'),
      );

- §

  #### Scene animation

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

      const report = reportSpeed('#reportmessage');

- §

  Create the Display cycle animation

      scrawl.makeRender({

          name: name('animation'),
          target: canvas,
          afterShow: report,
      });

- §

  #### User interaction

      scrawl.addNativeListener('change', (e) => {

          if (e && e.target) {

              e.preventDefault();
              e.stopPropagation();

              const value = e.target.value;

              switch (value) {

                  case 'horizontal' :

                      mygradient.set({
                          endX: '100%',
                          endY: 0,
                      });
                      break;

                  case 'vertical' :

                      mygradient.set({
                          endX: 0,
                          endY: '100%',
                      });
                      break;

                  case 'diagonal' :

                      mygradient.set({
                          endX: '100%',
                          endY: '100%',
                      });
                      break;
              }
          }
      }, '#gradient');

      scrawl.addNativeListener('change', (e) => {

          if (e && e.target) {

              e.preventDefault();
              e.stopPropagation();

              myGroup.setArtefacts({
                  justify: e.target.value,
              });
          }
      }, '#justify');

- §

  @ts-expect-error

      document.querySelector('#gradient').value = 'horizontal';

- §

  @ts-expect-error

      document.querySelector('#justify').value = 'left';

- §

  #### Development and testing

      console.log(scrawl.library);

- §

  Text measurements

  To see forthcoming measurements, we need to go to chrome://flags and enable ‘Experimental Web Platform Features’

  - The eventual aim is to replace a whole stack of code in factory/phrase.js where we calculate font height etc
  - At the moment Phrase entitys ignore font baselines; positioning is entirely from the top left corner of the text rectangle

      if ('fonts' in document) {

          Promise.all([
              document.fonts.load('18px Garamond'),
              document.fonts.load('46px "Mountains of Christmas"')
          ])
          .then(() => {

              const { engine } = canvas;

              engine.save();

              engine.font = '18px Garamond';
              const garamond = engine.measureText('The quick brown fox jumps over the lazy dog');
              console.log('garamond', garamond);

              engine.font = '46px "Mountains of Christmas"';
              const moc = engine.measureText('The quick brown fox jumps over the lazy dog');
              console.log('moc', moc);

              engine.restore();
          })
          .catch(e => console.log(e));
      }

      /*
      RESULTS - Chrome, with flag enabled

      garamond TextMetrics
          actualBoundingBoxAscent: 12.33984375
          actualBoundingBoxDescent: 3.9375
          actualBoundingBoxLeft: -0.24609375
          actualBoundingBoxRight: 328.376953125
          advances: [
              0, 10.9951171875, 19.9951171875, 27.984375, 32.484375, 41.484375, 50.484375, 55.4853515625, 63.474609375, 72.474609375, 76.974609375, 85.974609375, 91.96875, 100.96875, 113.9677734375, 122.9677734375, 127.4677734375, 133.4619140625, 142.4619140625, 151.4619140625, 155.9619140625, 160.962890625, 169.962890625, 183.9638671875, 192.9638671875, 199.96875, 204.46875, 213.46875, 222.46875, 230.4580078125, 236.4521484375, 240.9521484375, 245.953125, 254.953125, 262.9423828125, 267.4423828125, 272.443359375, 280.4326171875, 288.421875, 297.421875, 301.921875, 310.921875, 319.921875
          ]
          emHeightAscent: 13.5
          emHeightDescent: 4.5
          fontBoundingBoxAscent: 17
          fontBoundingBoxDescent: 5
          width: 328.921875

      RESULTS - Chrome, with flag disabled

      garamond TextMetrics
          actualBoundingBoxAscent: 12.33984375
          actualBoundingBoxDescent: 3.9375
          actualBoundingBoxLeft: -0.24609375
          actualBoundingBoxRight: 328.376953125
          fontBoundingBoxAscent: 17
          fontBoundingBoxDescent: 5
          width: 328.921875

      */