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static_canvas.class.ts
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static_canvas.class.ts
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//@ts-nocheck
import { config } from './config';
import { VERSION } from './constants';
import { Observable } from './mixins/observable.mixin';
import { Point } from './point.class';
import { requestAnimFrame } from './util/animate';
import { removeFromArray } from './util/internals';
import { pick } from './util/misc/pick';
import { FabricObject } from './shapes/object.class';
import { CommonMethods } from './mixins/shared_methods.mixin';
(function (global) {
// aliases for faster resolution
var fabric = global.fabric,
extend = fabric.util.object.extend,
getElementOffset = fabric.util.getElementOffset,
toFixed = fabric.util.toFixed,
transformPoint = fabric.util.transformPoint,
invertTransform = fabric.util.invertTransform,
getNodeCanvas = fabric.util.getNodeCanvas,
createCanvasElement = fabric.util.createCanvasElement,
CANVAS_INIT_ERROR = new Error('Could not initialize `canvas` element');
/**
* Static canvas class
* @class fabric.StaticCanvas
* @mixes fabric.Collection
* @mixes fabric.Observable
* @see {@link http://fabricjs.com/static_canvas|StaticCanvas demo}
* @see {@link fabric.StaticCanvas#initialize} for constructor definition
* @fires before:render
* @fires after:render
* @fires canvas:cleared
* @fires object:added
* @fires object:removed
*/
// eslint-disable-next-line max-len
fabric.StaticCanvas = fabric.util.createClass(
fabric.Collection,
/** @lends fabric.StaticCanvas.prototype */ {
/**
* Constructor
* @param {HTMLElement | String} el <canvas> element to initialize instance on
* @param {Object} [options] Options object
* @return {Object} thisArg
*/
initialize: function (el, options) {
options || (options = {});
this.renderAndResetBound = this.renderAndReset.bind(this);
this.requestRenderAllBound = this.requestRenderAll.bind(this);
this._initStatic(el, options);
},
/**
* Background color of canvas instance.
* @type {(String|fabric.Pattern)}
* @default
*/
backgroundColor: '',
/**
* Background image of canvas instance.
* since 2.4.0 image caching is active, please when putting an image as background, add to the
* canvas property a reference to the canvas it is on. Otherwise the image cannot detect the zoom
* vale. As an alternative you can disable image objectCaching
* @type fabric.Image
* @default
*/
backgroundImage: null,
/**
* Overlay color of canvas instance.
* @since 1.3.9
* @type {(String|fabric.Pattern)}
* @default
*/
overlayColor: '',
/**
* Overlay image of canvas instance.
* since 2.4.0 image caching is active, please when putting an image as overlay, add to the
* canvas property a reference to the canvas it is on. Otherwise the image cannot detect the zoom
* vale. As an alternative you can disable image objectCaching
* @type fabric.Image
* @default
*/
overlayImage: null,
/**
* Indicates whether toObject/toDatalessObject should include default values
* if set to false, takes precedence over the object value.
* @type Boolean
* @default
*/
includeDefaultValues: true,
/**
* Indicates whether objects' state should be saved
* @type Boolean
* @default
*/
stateful: false,
/**
* Indicates whether {@link fabric.Collection.add}, {@link fabric.Collection.insertAt} and {@link fabric.Collection.remove},
* {@link fabric.StaticCanvas.moveTo}, {@link fabric.StaticCanvas.clear} and many more, should also re-render canvas.
* Disabling this option will not give a performance boost when adding/removing a lot of objects to/from canvas at once
* since the renders are quequed and executed one per frame.
* Disabling is suggested anyway and managing the renders of the app manually is not a big effort ( canvas.requestRenderAll() )
* Left default to true to do not break documentation and old app, fiddles.
* @type Boolean
* @default
*/
renderOnAddRemove: true,
/**
* Indicates whether object controls (borders/controls) are rendered above overlay image
* @type Boolean
* @default
*/
controlsAboveOverlay: false,
/**
* Indicates whether the browser can be scrolled when using a touchscreen and dragging on the canvas
* @type Boolean
* @default
*/
allowTouchScrolling: false,
/**
* Indicates whether this canvas will use image smoothing, this is on by default in browsers
* @type Boolean
* @default
*/
imageSmoothingEnabled: true,
/**
* The transformation (a Canvas 2D API transform matrix) which focuses the viewport
* @type Array
* @example <caption>Default transform</caption>
* canvas.viewportTransform = [1, 0, 0, 1, 0, 0];
* @example <caption>Scale by 70% and translate toward bottom-right by 50, without skewing</caption>
* canvas.viewportTransform = [0.7, 0, 0, 0.7, 50, 50];
* @default
*/
viewportTransform: fabric.iMatrix.concat(),
/**
* if set to false background image is not affected by viewport transform
* @since 1.6.3
* @type Boolean
* @default
*/
backgroundVpt: true,
/**
* if set to false overlya image is not affected by viewport transform
* @since 1.6.3
* @type Boolean
* @default
*/
overlayVpt: true,
/**
* When true, canvas is scaled by devicePixelRatio for better rendering on retina screens
* @type Boolean
* @default
*/
enableRetinaScaling: true,
/**
* Describe canvas element extension over design
* properties are tl,tr,bl,br.
* if canvas is not zoomed/panned those points are the four corner of canvas
* if canvas is viewportTransformed you those points indicate the extension
* of canvas element in plain untrasformed coordinates
* The coordinates get updated with @method calcViewportBoundaries.
* @memberOf fabric.StaticCanvas.prototype
*/
vptCoords: {},
/**
* Based on vptCoords and object.aCoords, skip rendering of objects that
* are not included in current viewport.
* May greatly help in applications with crowded canvas and use of zoom/pan
* If One of the corner of the bounding box of the object is on the canvas
* the objects get rendered.
* @memberOf fabric.StaticCanvas.prototype
* @type Boolean
* @default
*/
skipOffscreen: true,
/**
* a fabricObject that, without stroke define a clipping area with their shape. filled in black
* the clipPath object gets used when the canvas has rendered, and the context is placed in the
* top left corner of the canvas.
* clipPath will clip away controls, if you do not want this to happen use controlsAboveOverlay = true
* @type fabric.Object
*/
clipPath: undefined,
/**
* @private
* @param {HTMLElement | String} el <canvas> element to initialize instance on
* @param {Object} [options] Options object
*/
_initStatic: function (el, options) {
this._objects = [];
this._createLowerCanvas(el);
this._initOptions(options);
// only initialize retina scaling once
if (!this.interactive) {
this._initRetinaScaling();
}
this.calcOffset();
},
/**
* @private
*/
_isRetinaScaling: function () {
return config.devicePixelRatio > 1 && this.enableRetinaScaling;
},
/**
* @private
* @return {Number} retinaScaling if applied, otherwise 1;
*/
getRetinaScaling: function () {
return this._isRetinaScaling()
? Math.max(1, config.devicePixelRatio)
: 1;
},
/**
* @private
*/
_initRetinaScaling: function () {
if (!this._isRetinaScaling()) {
return;
}
var scaleRatio = config.devicePixelRatio;
this.__initRetinaScaling(
scaleRatio,
this.lowerCanvasEl,
this.contextContainer
);
if (this.upperCanvasEl) {
this.__initRetinaScaling(
scaleRatio,
this.upperCanvasEl,
this.contextTop
);
}
},
__initRetinaScaling: function (scaleRatio, canvas, context) {
canvas.setAttribute('width', this.width * scaleRatio);
canvas.setAttribute('height', this.height * scaleRatio);
context.scale(scaleRatio, scaleRatio);
},
/**
* Calculates canvas element offset relative to the document
* This method is also attached as "resize" event handler of window
* @return {fabric.Canvas} instance
* @chainable
*/
calcOffset: function () {
this._offset = getElementOffset(this.lowerCanvasEl);
return this;
},
/**
* @private
*/
_createCanvasElement: function () {
var element = createCanvasElement();
if (!element) {
throw CANVAS_INIT_ERROR;
}
if (!element.style) {
element.style = {};
}
if (typeof element.getContext === 'undefined') {
throw CANVAS_INIT_ERROR;
}
return element;
},
/**
* @private
* @param {Object} [options] Options object
*/
_initOptions: function (options) {
var lowerCanvasEl = this.lowerCanvasEl;
this.set(options);
this.width = this.width || parseInt(lowerCanvasEl.width, 10) || 0;
this.height = this.height || parseInt(lowerCanvasEl.height, 10) || 0;
if (!this.lowerCanvasEl.style) {
return;
}
lowerCanvasEl.width = this.width;
lowerCanvasEl.height = this.height;
lowerCanvasEl.style.width = this.width + 'px';
lowerCanvasEl.style.height = this.height + 'px';
this.viewportTransform = this.viewportTransform.slice();
},
/**
* Creates a bottom canvas
* @private
* @param {HTMLElement} [canvasEl]
*/
_createLowerCanvas: function (canvasEl) {
// canvasEl === 'HTMLCanvasElement' does not work on jsdom/node
if (canvasEl && canvasEl.getContext) {
this.lowerCanvasEl = canvasEl;
} else {
this.lowerCanvasEl =
fabric.document.getElementById(canvasEl) ||
canvasEl ||
this._createCanvasElement();
}
if (this.lowerCanvasEl.hasAttribute('data-fabric')) {
/* _DEV_MODE_START_ */
throw new Error(
'fabric.js: trying to initialize a canvas that has already been initialized'
);
/* _DEV_MODE_END_ */
}
this.lowerCanvasEl.classList.add('lower-canvas');
this.lowerCanvasEl.setAttribute('data-fabric', 'main');
if (this.interactive) {
this._originalCanvasStyle = this.lowerCanvasEl.style.cssText;
this._applyCanvasStyle(this.lowerCanvasEl);
}
this.contextContainer = this.lowerCanvasEl.getContext('2d');
},
/**
* Returns canvas width (in px)
* @return {Number}
*/
getWidth: function () {
return this.width;
},
/**
* Returns canvas height (in px)
* @return {Number}
*/
getHeight: function () {
return this.height;
},
/**
* Sets width of this canvas instance
* @param {Number|String} value Value to set width to
* @param {Object} [options] Options object
* @param {Boolean} [options.backstoreOnly=false] Set the given dimensions only as canvas backstore dimensions
* @param {Boolean} [options.cssOnly=false] Set the given dimensions only as css dimensions
* @return {fabric.Canvas} instance
* @chainable true
*/
setWidth: function (value, options) {
return this.setDimensions({ width: value }, options);
},
/**
* Sets height of this canvas instance
* @param {Number|String} value Value to set height to
* @param {Object} [options] Options object
* @param {Boolean} [options.backstoreOnly=false] Set the given dimensions only as canvas backstore dimensions
* @param {Boolean} [options.cssOnly=false] Set the given dimensions only as css dimensions
* @return {fabric.Canvas} instance
* @chainable true
*/
setHeight: function (value, options) {
return this.setDimensions({ height: value }, options);
},
/**
* Sets dimensions (width, height) of this canvas instance. when options.cssOnly flag active you should also supply the unit of measure (px/%/em)
* @param {Object} dimensions Object with width/height properties
* @param {Number|String} [dimensions.width] Width of canvas element
* @param {Number|String} [dimensions.height] Height of canvas element
* @param {Object} [options] Options object
* @param {Boolean} [options.backstoreOnly=false] Set the given dimensions only as canvas backstore dimensions
* @param {Boolean} [options.cssOnly=false] Set the given dimensions only as css dimensions
* @return {fabric.Canvas} thisArg
* @chainable
*/
setDimensions: function (dimensions, options) {
var cssValue;
options = options || {};
for (var prop in dimensions) {
cssValue = dimensions[prop];
if (!options.cssOnly) {
this._setBackstoreDimension(prop, dimensions[prop]);
cssValue += 'px';
this.hasLostContext = true;
}
if (!options.backstoreOnly) {
this._setCssDimension(prop, cssValue);
}
}
if (this._isCurrentlyDrawing) {
this.freeDrawingBrush &&
this.freeDrawingBrush._setBrushStyles(this.contextTop);
}
this._initRetinaScaling();
this.calcOffset();
if (!options.cssOnly) {
this.requestRenderAll();
}
return this;
},
/**
* Helper for setting width/height
* @private
* @param {String} prop property (width|height)
* @param {Number} value value to set property to
* @return {fabric.Canvas} instance
* @chainable true
*/
_setBackstoreDimension: function (prop, value) {
this.lowerCanvasEl[prop] = value;
if (this.upperCanvasEl) {
this.upperCanvasEl[prop] = value;
}
if (this.cacheCanvasEl) {
this.cacheCanvasEl[prop] = value;
}
this[prop] = value;
return this;
},
/**
* Helper for setting css width/height
* @private
* @param {String} prop property (width|height)
* @param {String} value value to set property to
* @return {fabric.Canvas} instance
* @chainable true
*/
_setCssDimension: function (prop, value) {
this.lowerCanvasEl.style[prop] = value;
if (this.upperCanvasEl) {
this.upperCanvasEl.style[prop] = value;
}
if (this.wrapperEl) {
this.wrapperEl.style[prop] = value;
}
return this;
},
/**
* Returns canvas zoom level
* @return {Number}
*/
getZoom: function () {
return this.viewportTransform[0];
},
/**
* Sets viewport transformation of this canvas instance
* @param {Array} vpt a Canvas 2D API transform matrix
* @return {fabric.Canvas} instance
* @chainable true
*/
setViewportTransform: function (vpt) {
var activeObject = this._activeObject,
backgroundObject = this.backgroundImage,
overlayObject = this.overlayImage,
object,
i,
len;
this.viewportTransform = vpt;
for (i = 0, len = this._objects.length; i < len; i++) {
object = this._objects[i];
object.group || object.setCoords(true);
}
if (activeObject) {
activeObject.setCoords();
}
if (backgroundObject) {
backgroundObject.setCoords(true);
}
if (overlayObject) {
overlayObject.setCoords(true);
}
this.calcViewportBoundaries();
this.renderOnAddRemove && this.requestRenderAll();
return this;
},
/**
* Sets zoom level of this canvas instance, the zoom centered around point
* meaning that following zoom to point with the same point will have the visual
* effect of the zoom originating from that point. The point won't move.
* It has nothing to do with canvas center or visual center of the viewport.
* @param {Point} point to zoom with respect to
* @param {Number} value to set zoom to, less than 1 zooms out
* @return {fabric.Canvas} instance
* @chainable true
*/
zoomToPoint: function (point, value) {
// TODO: just change the scale, preserve other transformations
var before = point,
vpt = this.viewportTransform.slice(0);
point = transformPoint(point, invertTransform(this.viewportTransform));
vpt[0] = value;
vpt[3] = value;
var after = transformPoint(point, vpt);
vpt[4] += before.x - after.x;
vpt[5] += before.y - after.y;
return this.setViewportTransform(vpt);
},
/**
* Sets zoom level of this canvas instance
* @param {Number} value to set zoom to, less than 1 zooms out
* @return {fabric.Canvas} instance
* @chainable true
*/
setZoom: function (value) {
this.zoomToPoint(new Point(0, 0), value);
return this;
},
/**
* Pan viewport so as to place point at top left corner of canvas
* @param {Point} point to move to
* @return {fabric.Canvas} instance
* @chainable true
*/
absolutePan: function (point) {
var vpt = this.viewportTransform.slice(0);
vpt[4] = -point.x;
vpt[5] = -point.y;
return this.setViewportTransform(vpt);
},
/**
* Pans viewpoint relatively
* @param {Point} point (position vector) to move by
* @return {fabric.Canvas} instance
* @chainable true
*/
relativePan: function (point) {
return this.absolutePan(
new Point(
-point.x - this.viewportTransform[4],
-point.y - this.viewportTransform[5]
)
);
},
/**
* Returns <canvas> element corresponding to this instance
* @return {HTMLCanvasElement}
*/
getElement: function () {
return this.lowerCanvasEl;
},
/**
* @param {...fabric.Object} objects to add
* @return {Self} thisArg
* @chainable
*/
add: function () {
fabric.Collection.add.call(this, arguments, this._onObjectAdded);
arguments.length > 0 &&
this.renderOnAddRemove &&
this.requestRenderAll();
return this;
},
/**
* Inserts an object into collection at specified index, then renders canvas (if `renderOnAddRemove` is not `false`)
* An object should be an instance of (or inherit from) fabric.Object
* @param {fabric.Object|fabric.Object[]} objects Object(s) to insert
* @param {Number} index Index to insert object at
* @param {Boolean} nonSplicing When `true`, no splicing (shifting) of objects occurs
* @return {Self} thisArg
* @chainable
*/
insertAt: function (objects, index) {
fabric.Collection.insertAt.call(
this,
objects,
index,
this._onObjectAdded
);
(Array.isArray(objects) ? objects.length > 0 : !!objects) &&
this.renderOnAddRemove &&
this.requestRenderAll();
return this;
},
/**
* @param {...fabric.Object} objects to remove
* @return {Self} thisArg
* @chainable
*/
remove: function () {
var removed = fabric.Collection.remove.call(
this,
arguments,
this._onObjectRemoved
);
removed.length > 0 && this.renderOnAddRemove && this.requestRenderAll();
return this;
},
/**
* @private
* @param {fabric.Object} obj Object that was added
*/
_onObjectAdded: function (obj) {
this.stateful && obj.setupState();
if (obj.canvas && obj.canvas !== this) {
/* _DEV_MODE_START_ */
console.warn(
'fabric.Canvas: trying to add an object that belongs to a different canvas.\n' +
'Resulting to default behavior: removing object from previous canvas and adding to new canvas'
);
/* _DEV_MODE_END_ */
obj.canvas.remove(obj);
}
obj._set('canvas', this);
obj.setCoords();
this.fire('object:added', { target: obj });
obj.fire('added', { target: this });
},
/**
* @private
* @param {fabric.Object} obj Object that was removed
*/
_onObjectRemoved: function (obj) {
obj._set('canvas', undefined);
this.fire('object:removed', { target: obj });
obj.fire('removed', { target: this });
},
/**
* Clears specified context of canvas element
* @param {CanvasRenderingContext2D} ctx Context to clear
* @return {fabric.Canvas} thisArg
* @chainable
*/
clearContext: function (ctx) {
ctx.clearRect(0, 0, this.width, this.height);
return this;
},
/**
* Returns context of canvas where objects are drawn
* @return {CanvasRenderingContext2D}
*/
getContext: function () {
return this.contextContainer;
},
/**
* Clears all contexts (background, main, top) of an instance
* @return {fabric.Canvas} thisArg
* @chainable
*/
clear: function () {
this.remove.apply(this, this.getObjects());
this.backgroundImage = null;
this.overlayImage = null;
this.backgroundColor = '';
this.overlayColor = '';
if (this._hasITextHandlers) {
this.off('mouse:up', this._mouseUpITextHandler);
this._iTextInstances = null;
this._hasITextHandlers = false;
}
this.clearContext(this.contextContainer);
this.fire('canvas:cleared');
this.renderOnAddRemove && this.requestRenderAll();
return this;
},
/**
* Renders the canvas
* @return {fabric.Canvas} instance
* @chainable
*/
renderAll: function () {
this.cancelRequestedRender();
if (this.destroyed) {
return;
}
this.renderCanvas(this.contextContainer, this._objects);
return this;
},
/**
* Function created to be instance bound at initialization
* used in requestAnimationFrame rendering
* Let the fabricJS call it. If you call it manually you could have more
* animationFrame stacking on to of each other
* for an imperative rendering, use canvas.renderAll
* @private
* @return {fabric.Canvas} instance
* @chainable
*/
renderAndReset: function () {
this.nextRenderHandle = 0;
this.renderAll();
},
/**
* Append a renderAll request to next animation frame.
* unless one is already in progress, in that case nothing is done
* a boolean flag will avoid appending more.
* @return {fabric.Canvas} instance
* @chainable
*/
requestRenderAll: function () {
if (!this.nextRenderHandle && !this.disposed && !this.destroyed) {
this.nextRenderHandle = requestAnimFrame(this.renderAndResetBound);
}
return this;
},
/**
* Calculate the position of the 4 corner of canvas with current viewportTransform.
* helps to determinate when an object is in the current rendering viewport using
* object absolute coordinates ( aCoords )
* @return {Object} points.tl
* @chainable
*/
calcViewportBoundaries: function () {
var width = this.width,
height = this.height,
iVpt = invertTransform(this.viewportTransform),
a = transformPoint({ x: 0, y: 0 }, iVpt),
b = transformPoint({ x: width, y: height }, iVpt),
// we don't support vpt flipping
// but the code is robust enough to mostly work with flipping
min = a.min(b),
max = a.max(b);
return (this.vptCoords = {
tl: min,
tr: new Point(max.x, min.y),
bl: new Point(min.x, max.y),
br: max,
});
},
cancelRequestedRender: function () {
if (this.nextRenderHandle) {
fabric.util.cancelAnimFrame(this.nextRenderHandle);
this.nextRenderHandle = 0;
}
},
/**
* Renders background, objects, overlay and controls.
* @param {CanvasRenderingContext2D} ctx
* @param {Array} objects to render
* @return {fabric.Canvas} instance
* @chainable
*/
renderCanvas: function (ctx, objects) {
if (this.destroyed) {
return;
}
var v = this.viewportTransform,
path = this.clipPath;
this.calcViewportBoundaries();
this.clearContext(ctx);
ctx.imageSmoothingEnabled = this.imageSmoothingEnabled;
// node-canvas
ctx.patternQuality = 'best';
this.fire('before:render', { ctx: ctx });
this._renderBackground(ctx);
ctx.save();
//apply viewport transform once for all rendering process
ctx.transform(v[0], v[1], v[2], v[3], v[4], v[5]);
this._renderObjects(ctx, objects);
ctx.restore();
if (!this.controlsAboveOverlay && this.interactive) {
this.drawControls(ctx);
}
if (path) {
path._set('canvas', this);
// needed to setup a couple of variables
path.shouldCache();
path._transformDone = true;
path.renderCache({ forClipping: true });
this.drawClipPathOnCanvas(ctx);
}
this._renderOverlay(ctx);
if (this.controlsAboveOverlay && this.interactive) {
this.drawControls(ctx);
}
this.fire('after:render', { ctx: ctx });
if (this.__cleanupTask) {
this.__cleanupTask();
this.__cleanupTask = undefined;
}
},
/**
* Paint the cached clipPath on the lowerCanvasEl
* @param {CanvasRenderingContext2D} ctx Context to render on
*/
drawClipPathOnCanvas: function (ctx) {
var v = this.viewportTransform,
path = this.clipPath;
ctx.save();
ctx.transform(v[0], v[1], v[2], v[3], v[4], v[5]);
// DEBUG: uncomment this line, comment the following
// ctx.globalAlpha = 0.4;
ctx.globalCompositeOperation = 'destination-in';
path.transform(ctx);
ctx.scale(1 / path.zoomX, 1 / path.zoomY);
ctx.drawImage(
path._cacheCanvas,
-path.cacheTranslationX,
-path.cacheTranslationY
);
ctx.restore();
},
/**
* @private
* @param {CanvasRenderingContext2D} ctx Context to render on
* @param {Array} objects to render
*/
_renderObjects: function (ctx, objects) {
var i, len;
for (i = 0, len = objects.length; i < len; ++i) {
objects[i] && objects[i].render(ctx);
}
},
/**
* @private
* @param {CanvasRenderingContext2D} ctx Context to render on
* @param {string} property 'background' or 'overlay'
*/
_renderBackgroundOrOverlay: function (ctx, property) {
var fill = this[property + 'Color'],
object = this[property + 'Image'],
v = this.viewportTransform,
needsVpt = this[property + 'Vpt'];
if (!fill && !object) {
return;
}
if (fill) {
ctx.save();
ctx.beginPath();
ctx.moveTo(0, 0);
ctx.lineTo(this.width, 0);
ctx.lineTo(this.width, this.height);
ctx.lineTo(0, this.height);
ctx.closePath();
ctx.fillStyle = fill.toLive ? fill.toLive(ctx, this) : fill;
if (needsVpt) {
ctx.transform(v[0], v[1], v[2], v[3], v[4], v[5]);
}
ctx.transform(1, 0, 0, 1, fill.offsetX || 0, fill.offsetY || 0);
var m = fill.gradientTransform || fill.patternTransform;
m && ctx.transform(m[0], m[1], m[2], m[3], m[4], m[5]);
ctx.fill();
ctx.restore();
}
if (object) {
ctx.save();
if (needsVpt) {
ctx.transform(v[0], v[1], v[2], v[3], v[4], v[5]);
}
object.render(ctx);
ctx.restore();
}
},
/**
* @private
* @param {CanvasRenderingContext2D} ctx Context to render on
*/
_renderBackground: function (ctx) {
this._renderBackgroundOrOverlay(ctx, 'background');
},
/**
* @private
* @param {CanvasRenderingContext2D} ctx Context to render on
*/
_renderOverlay: function (ctx) {
this._renderBackgroundOrOverlay(ctx, 'overlay');
},
/**
* Returns coordinates of a center of canvas.
* Returned value is an object with top and left properties
* @return {Object} object with "top" and "left" number values
* @deprecated migrate to `getCenterPoint`
*/
getCenter: function () {
return {
top: this.height / 2,
left: this.width / 2,
};
},
/**
* Returns coordinates of a center of canvas.
* @return {Point}
*/
getCenterPoint: function () {
return new Point(this.width / 2, this.height / 2);
},
/**
* Centers object horizontally in the canvas
* @param {fabric.Object} object Object to center horizontally
* @return {fabric.Canvas} thisArg
*/
centerObjectH: function (object) {
return this._centerObject(
object,
new Point(this.getCenterPoint().x, object.getCenterPoint().y)
);
},
/**
* Centers object vertically in the canvas
* @param {fabric.Object} object Object to center vertically
* @return {fabric.Canvas} thisArg
* @chainable
*/
centerObjectV: function (object) {
return this._centerObject(
object,
new Point(object.getCenterPoint().x, this.getCenterPoint().y)
);
},
/**
* Centers object vertically and horizontally in the canvas
* @param {fabric.Object} object Object to center vertically and horizontally
* @return {fabric.Canvas} thisArg
* @chainable
*/
centerObject: function (object) {
var center = this.getCenterPoint();
return this._centerObject(object, center);
},
/**
* Centers object vertically and horizontally in the viewport
* @param {fabric.Object} object Object to center vertically and horizontally
* @return {fabric.Canvas} thisArg
* @chainable
*/
viewportCenterObject: function (object) {
var vpCenter = this.getVpCenter();
return this._centerObject(object, vpCenter);
},
/**
* Centers object horizontally in the viewport, object.top is unchanged
* @param {fabric.Object} object Object to center vertically and horizontally
* @return {fabric.Canvas} thisArg
* @chainable
*/
viewportCenterObjectH: function (object) {