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  ./source/core/animation-loop.js ./source/core/display-cycle.js ./source/core/document-root-elements.js ./source/core/document.js ./source/core/events.js ./source/core/init.js ./source/core/library.js ./source/core/random-seed.js ./source/core/shared-vars.js ./source/core/snippets.js ./source/core/system-flags.js ./source/core/user-interaction.js ./source/core/utilities.js ./source/factory/action.js ./source/factory/anchor.js ./source/factory/animation.js ./source/factory/array-pool.js ./source/factory/bezier.js ./source/factory/block.js ./source/factory/canvas.js ./source/factory/cell-fragment.js ./source/factory/cell.js ./source/factory/cog.js ./source/factory/color.js ./source/factory/conic-gradient.js ./source/factory/coordinate.js ./source/factory/crescent.js ./source/factory/drag-zone.js ./source/factory/element.js ./source/factory/emitter.js ./source/factory/filter-engine-bluenoise-data.js ./source/factory/filter-engine.js ./source/factory/filter.js ./source/factory/font-attributes.js ./source/factory/gradient.js ./source/factory/grid.js ./source/factory/group.js ./source/factory/image-asset.js ./source/factory/keyboard-zone.js ./source/factory/line-spiral.js ./source/factory/line.js ./source/factory/loom.js ./source/factory/mesh.js ./source/factory/net.js ./source/factory/noise-asset.js ./source/factory/observe-update.js ./source/factory/oval.js ./source/factory/palette.js ./source/factory/particle-force.js ./source/factory/particle-history.js ./source/factory/particle-spring.js ./source/factory/particle-world.js ./source/factory/particle.js ./source/factory/pattern.js ./source/factory/phrase.js ./source/factory/picture.js ./source/factory/polygon.js ./source/factory/polyline.js ./source/factory/quadratic.js ./source/factory/quaternion.js ./source/factory/radial-gradient.js ./source/factory/raw-asset.js ./source/factory/reaction-diffusion-asset.js ./source/factory/rectangle.js ./source/factory/render-animation.js ./source/factory/shape.js ./source/factory/spiral.js ./source/factory/sprite-asset.js ./source/factory/stack.js ./source/factory/star.js ./source/factory/state.js ./source/factory/tetragon.js ./source/factory/ticker.js ./source/factory/tracer.js ./source/factory/tween.js ./source/factory/unstacked-element.js ./source/factory/vector.js ./source/factory/video-asset.js ./source/factory/wheel.js ./source/mixin/anchor.js ./source/mixin/asset-advanced-functionality.js ./source/mixin/asset-consumer.js ./source/mixin/asset.js ./source/mixin/base.js ./source/mixin/cascade.js ./source/mixin/cell-key-functions.js ./source/mixin/delta.js ./source/mixin/display-shape.js ./source/mixin/dom.js ./source/mixin/entity.js ./source/mixin/filter.js ./source/mixin/mimic.js ./source/mixin/path.js ./source/mixin/pattern.js ./source/mixin/pivot.js ./source/mixin/position.js ./source/mixin/shape-basic.js ./source/mixin/shape-curve.js ./source/mixin/shape-path-calculation.js ./source/mixin/styles.js ./source/mixin/tween.js

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  # The Display cycle

  Scrawl-canvas breaks down the Display cycle into three parts: clear; compile; and show. These can be triggered either as a single, combined render operation, or separately as-and-when needed.

  The order in which DOM stack and canvas elements are processed during the display cycle can be changed by setting that element’s controller’s order attribute to a higher or lower integer value; elements are processed (in batches) from lowest to highest order value

  Each display cycle function is a normal Javascript function, invoked with no arguments and returning no status

  Note that Scrawl-canvas supplies a convenience function - makeRender() - for automating the process of creating an animation object to handle the Display cycle

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  #### Imports

      import { artefact } from "./library.js";

      import { getSortedRootElements } from './document-root-elements.js';

      import { CLEAR, COMPILE, SHOW, RENDER } from './shared-vars.js';

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  Helper functions coordinate the actions required to complete a display cycle

      const displayCycleHelper = function (items) {

          if (items.length) return items;
          return getSortedRootElements();
      };

      const displayCycleBatchProcess = function (rootWrappers, method) {

          let i, iz, item;

          for (i = 0, iz = rootWrappers.length; i < iz; i++) {

              item = artefact[rootWrappers[i]];

              if (item && item[method]) item[method]();
          }
      };

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  ##### Clear

  - For canvas artefacts, clear its Cell assets’ display (reset all pixels to 0, or the designated background color) ready for them to be redrawn
  - For stack artefacts - no action required
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  `Exported function` (to modules and scrawl object).

      export const clear = function (...items) {

          const wrappers = displayCycleHelper(items);
          displayCycleBatchProcess(wrappers, CLEAR);
      };

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  ##### Compile

  - For both canvas and stack artefacts, perform necessary entity/element positional calculations
  - Additionally for canvas artefacts, stamp associated entitys onto the canvas’s constituent cell assets
- §

  `Exported function` (to modules and scrawl object).

      export const compile = function (...items) {

          const wrappers = displayCycleHelper(items);
          displayCycleBatchProcess(wrappers, COMPILE);
      };

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  ##### Show

  - For canvas artefacts, stamp additional ‘layer’ canvases onto the base canvas, then copy the base canvas onto the display canvas
  - For stack artefacts - invoke the domShow function, if any of its constituent elements require DOM-related updating
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  `Exported function` (to modules and scrawl object).

      export const show = function (...items) {

          const wrappers = displayCycleHelper(items);
          displayCycleBatchProcess(wrappers, SHOW);
      };

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  ##### Render

  - Orchestrate the clear, compile and show actions on each stack and canvas DOM element
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  `Exported function` (to modules and scrawl object).

      export const render = function (...items) {

          const wrappers = displayCycleHelper(items);
          displayCycleBatchProcess(wrappers, RENDER);
      };