Editor properties

Doka Image Editor exposes a set of properties that enable us to update the editor state.

• Editor properties
• Image properties
• Markup editor properties

Editor properties

These read only properties are available on the editor instance.

HTMLElement

HTMLElement

These read/write properties are available on the editor instance.

undefined

undefined

undefined

undefined

undefined

undefined

'auto'

'auto'

10

false

undefined

undefined

undefined

undefined

undefined

true

true

false

true

true

true

false

undefined

undefined

undefined

undefined

src

The source image to load. Update to load a new image.

Accepts:

• File
• Blob
• DataURL
• URL
• HTMLCanvasElement
• HTMLImageElement

import { openEditor } from './doka.js';

openEditor({
    src: './my-image.jpeg',
});

locale

The editor requires the locale property to be set to a valid locale object.

In the example below we assign the core editor locale and the crop plugin locale object.

import { openEditor, locale_en_gb, plugin_crop_locale_en_gb } from 'doka.js';

// Merge the locale objects
const myLocale = {
    ...locale_en_gb,
    ...plugin_crop_locale_en_gb,
};

// Assign locale to editor
openEditor({
    src: 'my-image.jpeg',
    locale: myLocale,
});

See below for an example of the locale_en_gb object exported by the editor module.

{
    labelDefault: 'Default',
    labelReset: 'Reset',
    labelAuto: 'Auto',
    labelNone: 'None',
    labelEdit: 'Edit',
    labelClose: 'Close',

    // etc...
}

To change a label we can update one of the properties in the locale object.

// Merge the locale objects
const myLocale = {
    ...locale_en_gb,
    ...plugin_crop_locale_en_gb,
};

// Change label of export button to 'Save'
myLocale.labelButtonExport = 'Save';

The code below logs all locale properties to the developer console so we can easily see which property to edit if we need to change labels or icons.

import {
    // core locale
    locale_en_gb,

    // plugin locale
    plugin_crop_locale_en_gb,
    plugin_finetune_locale_en_gb,
    plugin_filter_locale_en_gb,
    plugin_annotate_locale_en_gb,
    plugin_decorate_locale_en_gb,
    plugin_resize_locale_en_gb,
    plugin_sticker_locale_en_gb,

    // markup editor locale
    markup_editor_locale_en_gb,
} from './doka.js';

// log merged objects to console
console.log({
    ...locale_en_gb,
    ...plugin_crop_locale_en_gb,
    ...plugin_finetune_locale_en_gb,
    ...plugin_filter_locale_en_gb,
    ...plugin_annotate_locale_en_gb,
    ...plugin_decorate_locale_en_gb,
    ...plugin_resize_locale_en_gb,
    ...plugin_sticker_locale_en_gb,
    ...markup_editor_locale_en_gb,
});

modal

A reference to the modal wrapping the editor. This property is only available when the editor is created with openEditor.

util

Updates the current active util and will trigger the editor to show the corresponding view.

doka.util = 'finetune';

utils

Use to set which utils are shown and in what order they appear in the editor menu.

doka.utils = ['crop', 'filter', 'finetune'];

animations

Toggle if and when the editor runs animations.

'auto'

'never'

'always'

previewUpscale

If set to true the preview image will be scaled to fit the editor stage.

If false the preview image will only be scaled down to fit the stage, if the preview image is smaller than the stage it will not be upscaled.

imageSourceToImageData

A helper method to correctly read custom preview image data.

The image formats that Doka can read and write depend on which images are supported by the clients browser. In general these image types are supported by all major browsers.

• image/gif
• image/png
• image/jpeg
• image/webp
• image/bmp
• image/svg

If we want to be able to read additional image formats (for example HEIC/HEIF) inside the editor we can supply our own image reader using the imageSourceToImageData property.

Please note that this function is used for all image resources inside the editor, if we only need to load additional image formats for editing it's better to set the preprocessImageFile hook of the imageReader property.

const app = openEditor({
    // Custom imageSourceToImageData method
    imageSourceToImageData: (src) =>
        fetch(src)
            .then((res) => res.blob())
            .then((blob) => {
                return new Promise((resolve, reject) => {
                    // Turn blob into image data here

                    // resolve with ImageData object
                    resolve(imageData);
                });
            }),
});

imageOrienter

Can be set to a helper object to correctly orient image data. This is useful for older browsers where interpretation of the EXIF orientation header is done incorrectly and images appear upside down or mirrored.

The property expects an object with an read and an apply function.

• The read function is used to read the EXIF orientation header from the image preview data.
• The apply function is used to apply the EXIF orientation header to the image preview.

We can import the createDefaultImageOrienter method and use it to set the imageOrienter property to automatically orient images.

import { createDefaultImageOrienter } from './doka.js';

const app = openEditor({
    imageOrienter: createDefaultImageOrienter(),
});

imageReader

Expects an array of read steps to step through when reading the src input image data.

We can import the createDefaultImageReader method and use it to set the imageReader property to read preview images.

import { openEditor, createDefaultImageReader } from './doka.js';

openEditor({
    imageReader: createDefaultImageReader(),
});

imageWriter

Expects an array of write steps to step through when writing the output image data.

We can import the createDefaultImageWriter method and use it to set the imageWriter property to write output images.

import { openEditor, createDefaultImageWriter } from './doka.js';

openEditor({
    imageWriter: createDefaultImageWriter(),
});

handleEvent

Set to a function to route events. The handleEvent callback runs for each public event the editor dispatches, it receives the event type and detail.

Overview of all editor events

import { openEditor } from './doka.js';

openEditor({
    handleEvent: (type, detail) => {
        // log all editor events to console
        console.log(type, detail);
    },
});

willRevert

Set to an async method.

Resolve with false to prevent the revert of all user actions, resolve with true to revert the editor to the initial state.

import { openEditor } from './doka.js';

openEditor({
    willRevert: () =>
        new Promise((resolve) => {
            /* determine if should revert */

            resolve(false); // false will cancel revert action
        }),
});

willRenderCanvas

We can use the willRenderCanvas hook to alter what Doka renders to the screen.

The willRenderCanvas hook receives two parameters, the shapes that are about to be drawn, and the current state.

Example draw state object.

{
    // is user currently interacting
    isInteracting: false,

    // will animate from 0 to 1 when interacting
    isInteractingFraction: 0,

    // opacity of the image from 0 to 1
    opacity: 1,

    // rotation of image
    rotation: {
        x: 0,
        y: 0,
        z: 0,
    },

    // scale of image
    scale: 0.615625,

    // size of canvas
    size: {
        width: 1040,
        height: 510,
    },

    // foreground color of canvas
    foregroundColor: [0, 0, 0],

    // background color of canvas
    backgroundColor: [1, 1, 1],

    // line color used in canvas
    lineColor: [0, 0, 0],

    // rectangle of editor root
    rootRect: {
        x: 0,
        y: 0,
        width: 1040,
        height: 510,
    },

    // rectangle of crop selection
    selectionRect: {
        x: 322,
        y: 60,
        height: 394,
        width: 522,
    },

    // rectangle of util
    stageRect: {
        x: 144,
        y: 60,
        width: 880,
        height: 394,
    },

    // opacity of each util, from 0 to 1
    utilVisibility: {
        annotate: 0,
        crop: 1,
        decorate: 0,
        filter: 0,
        finetune: 0,
        resize: 0,
        sticker: 0,
    },
};

Example shapes object.

{
    // these are drawn relative to the preview image
    annotationShapes: [
        {
            backgroundColor: [0, 1, 1],
            cornerRadius: 0,
            disableErase: true,
            height: 200,
            id: 'dgyf5b4cu',
            opacity: 1,
            rotation: 0,
            strokeColor: [0, 0, 0],
            strokeWidth: 0,
            width: 200,
            x: 20,
            y: 20,
        },
    ],

    // these are drawn relative to the crop selection
    decorationShapes: [],

    // these are drawn on top of the user interface
    interfaceShapes: [
        {
            id: 'image-selection-guide-row-0',
            opacity: 1,
            points: [
                { x: 322.475, y: 60 },
                { x: 844.525, y: 60 },
            ],
            strokeColor: [0, 0, 0],
            strokeWidth: 1,
        },
        // ...and some more shapes
    ],
};

In the snippet below we draw a circular overlay on top of the crop selection, see crop overlay example for a live preview.

import { openEditor } from './doka.js';

openEditor({
    // this method is synchronouse,
    // it's called before each render
    willRenderCanvas: (shapes, state) => {
        const { utilVisibility, selectionRect, backgroundColor, lineColor } =
            state;

        // exit if crop utils is not visible
        if (utilVisibility.crop <= 0) return shapes;

        // shortcuts to selection rect
        const { x, y, width, height } = selectionRect;

        // return updated shapes
        return {
            // copy props from shapes param
            ...shapes,

            // add an `ellipse` shape
            interfaceShapes: [
                {
                    x: x + width * 0.5,
                    y: y + height * 0.5,
                    rx: width * 0.5,
                    ry: height * 0.5,
                    opacity: utilVisibility.crop,
                    inverted: true,
                    backgroundColor: [...backgroundColor, 0.5],
                    strokeWidth: 1,
                    strokeColor: [...lineColor],
                },
                ...shapes.interfaceShapes,
            ],
        };
    },
});

willRenderToolbar

The willRenderToolbar hook receives the current toolbar definition and editor environment parameters. The hook allows injecting custom controls into the toolbar.

The method should always return the received toolbar. If an empty array is returned the toolbar is hidden.

import { openEditor } from './doka.js';

openEditor({
    willRenderToolbar: (toolbar, env, redraw) => {
        console.log(toolbar);
        // logs: [ Array(4), Array(4), Array(4) ]

        console.log(env);
        // logs: { orientation: "landscape", verticalSpace: "short", … }

        return toolbar;
    },
});

A toolbar item can either be a tag or a Svelte component. Each item needs to have a unique id. Children are only supported on the tag descriptor.

// tag
const toolbarItems = [
    // html tag item
    [
        'div', // only div is supported
        'my-unique-id',
        {
            class: 'my-class-name',
        },
        [
            // Svelte component item
            [
                SvelteComponent,
                'my-unique-id',
                {
                    label: 'Label',
                },
            ],
            // other children
        ],
    ],
    // other top level items
];

Image properties

Readonly image properties

Image properties to update image state

undefined

0

undefined

true

{ width:1, height:1 }

undefined

false

false

undefined

[]

[]

undefined

undefined

undefined

undefined

undefined

imageLoadState

The imageLoadState contains the load state of the current image as it is passed through the imageReader.

imageProcessState

The imageProcessState contains the process state of the current image as it is passed through the imageWriter.

imageCrop

The current crop rectangle is relative to the (optionally rotated) bounding box of the image.

In the diagram below we can see how this works. We've defined a 64 x 64 crop in the top left corner of the image.

• The dashed line illustrates the bounding box of the rotated image.
• The magenta square represents our 64 × 64 crop positioned relative to the image bounding box.

We can see how the crop rectangle updates when we rotate the image using the range input.

If we assign options to the editor creation command the crop will be set first and then the rotation. In the example below, no matter the order of the properties, the crop will be set first and then the image will be rotated.

import { openEditor, degToRad } from './doka.js';

openEditor({
    // 2. Rotate the image
    imageRotation: degToRad(45),

    // 1. Crop 64 x 64 image from top left corner
    imageCrop: {
        x: 0,
        y: 0,
        width: 64,
        height: 64,
    },
});

imageCropAspectRatio

Set the aspect ratio of the crop as a number. Set to undefined to not enforce a crop aspect ratio.

import { openEditor } from './doka.js';

openEditor({
    imageCropAspectRatio: 16 / 9,
});

imageCropLimitToImage

When set to true Doka will prevent cropping outside of the image edges.

When set to false we can make a crop outside of the image edges. This also means we can zoom out further and rotate the image without auto zoom. To control the background color of pixels outside of the image we can set the imageBackgroundColor prop.

imageBackgroundColor

Set the background color to use for the output image and the image preview in the editor.

import { degToRad } from './doka.js';

openEditor({
    // set to red
    imageBackgroundColor: [1, 0, 0],
});

If we like a more familiar way of setting colors we can use the colorStringToColorArray method exported by the Doka Image Editor module.

Transparent background colors are supported in the output image but the preview isn't rendered correctly in the editor.

imageState

The imageState property describes the current image state.

See below for an example:

{
    // transforms
    flipX: false,
    flipY: false,
    rotation: 0,
    crop: { x: 0, y: 0, width: 1024, height: 768 },
    cropAspectRatio: undefined,
    cropMinSize: { width: 1, height: 1 },
    cropMaxSize: { width: 32767, height: 32767 },
    cropLimitToImage: true,

    // shapes
    annotation: [
        {
            id: 'lme6159vp',
            x: 32,
            y: 64,
            width: 320,
            height: 256,
            backgroundColor: [1, 0, 0],
            strokeColor: [1, 1, 1, 0],
            strokeWidth: 0,
            cornerRadius: 0,
        }
    ],
    decoration: [],

    // filters
    colorMatrix: undefined,
    convolutionMatrix: undefined,
    gamma: undefined,
    vignette: undefined,

    // output
    backgroundColor: [0, 0, 0, 0],
    targetSize: undefined,
}

Markup editor properties

undefined

undefined

undefined

0

undefined

undefined

undefined

undefined

undefined

undefined

undefined

markupEditorToolbar

Use the markupEditorToolbar property to update the tools in the Markup Editor toolbar. The property should be set to an array of tool item definitions.

By default the Markup Editor defines the following tools (in this order).

The 'eraser' and 'preset' tool are special. Where other tools have a default shape declaration, the preset and eraser tools do not.

The preset tool will show a list of preset stickers, if defined, if not, the preset tool won't be visible. The eraser tool can be used to erase line and path based shapes.

We can use the createMarkupEditorToolbar helper function to generate the default toolbar items and make it easier to add our own toolbar items.

import { openEditor } from './doka.js';

openEditor({
    markupEditorToolbar: [
        ['sharpie', 'Sharpie', { disabled: true, icon: '<g></g>' }],
        ['eraser', 'Eraser', { disabled: false, icon: '<g></g>' }],
        ['rectangle', 'Rectangle', { disabled: false, icon: '<g></g>' }],
    ],
});

markupEditorToolStyles

The markupEditorToolStyles property should be set to an object that describes the default styles for each tool. Each key in this object correlates with a tool key in the toolbar array.

We can use the createMarkupEditorToolStyle and createMarkupEditorToolStyles helper function to set the default tool styles and to make it easier to generate custom style objects.

import {
    openEditor,
    createMarkupEditorToolStyles,
    createMarkupEditorToolStyle,
} from './doka.js';

openEditor({
    // create the default tool styles
    markupEditorToolStyles: createMarkupEditorToolStyles({
        // create the text tool style and override fontSize property
        text: createMarkupEditorToolStyle('text', {
            fontSize: '10%',
        }),
    }),
});

markupEditorShapeStyleControls

The markupEditorShapeStyleControls contains the definitions for the style controls to which are used to adjust the appearance of an active shape.

Each key in the object correlates with a shape style property. The value of the key is set to the component to render and the parameters to send to the component.

We can use the createMarkupEditorShapeStyleControls helper function to generate the default controls and to make it easier to generate custom style control objects.

import { openEditor } from './doka.js';

openEditor({
    markupEditorShapeStyleControls: {
        backgroundColor: [
            ColorPicker, // component
            {}, // settings
        ],
        fontFamily: [
            Dropdown, // component
            {}, // settings
        ],
        // ...
    },
});

willRenderShapePresetToolbar

Use to add custom buttons to the markup editor preset toolbar.

In the example below we create a custom smile button, but this functionality can also be used to import images from third party sources like Dropbox, show modals with custom sticker sources, or open additional editors.

import { openEditor, createNode } from './doka.js';

openEditor({
    willRenderShapePresetToolbar: (nodes, addPreset, env) => {
        // create smile button
        const smileButton = createNode('Button', 'smile-button', {
            label: 'Add smile',
            onclick: () => addPreset('😄'),
        });

        // add it to the node tree
        appendNode(smileButton, menu);

        // return the new node tree
        return nodes;
    },
});

beforeSelectShape

Runs before a shape is selected. Return false to prevent selecting the shape. Receives current selected shape and about to be selected target shape.

If current is undefined it means no shape is currently selected.

import { openEditor } from './doka.js'

openEditor({
    beforeSelectShape = (current, target) => {
        console.log('beforeSelectShape', target);
        return true;
    }
});

We can use the beforeSelectShape hook combined with the removeshape event to prevent auto selection of the next shape when a shape was removed.

import { openEditor } from './doka.js'

let removedShape;

const editor = openEditor({
    beforeSelectShape = (current, target) => {
        // if currently selected shape is the
        // shape that was just removed prevent selection
        // of next shape
        if (current === removedShape) return false;

        return true;
    }
});

editor.on('removeshape', (shape) => {
    removedShape = shape;
})

beforeDeselectShape

Runs before a shape is deselected. Return false to prevent deselecting the shape. Receives current selected shape and about to be selected target shape.

If target is undefined it means no shape is targetted.

import { openEditor } from './doka.js'

openEditor({
    beforeDeselectShape = (current, target) => {
        console.log('beforeDeselectShape', current);
        return true;
    }
});

beforeAddShape

Runs before a shape preset is added. Return false to prevent adding the shape.

Instead of using this hook, consider instead disabling the shape tools and sticker items using the disabled property.

import { openEditor } from './doka.js'

openEditor({
    beforeAddShape = (shape) => {
        console.log('beforeAddShape', shape);
        return true;
    }
});

beforeRemoveShape

Runs before a shape is removed.

Return false to prevent removal of a shape.

import { openEditor } from './doka.js'

openEditor({
    beforeRemoveShape = (shape) => {
        console.log('beforeRemoveShape', shape);
        return true;
    }
});

beforeUpdateShape

Runs before a shape is updated.

Return adjusted props to make changes to shape update.

import { openEditor } from './doka.js'

openEditor({
    beforeUpdateShape = (shape, props, context) => {
        console.log('beforeUpdateShape', shape, props, context);
        return props;
    }
});

willRenderShapeControls

Runs before the shape controls popup is rendered above a selected shape. Allows manipulating the shape controls popup element tree.

import { openEditor } from './doka.js'

openEditor({
    willRenderShapeControls = (controls, selectedShapeId) => {

        // manipulate shape controls here

        return controls;
    }
});