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static_canvas.class.ts
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static_canvas.class.ts
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// @ts-nocheck
import { getEnv } from '../env';
import { config } from '../config';
import { iMatrix, VERSION } from '../constants';
import type { CanvasEvents, StaticCanvasEvents } from '../EventTypeDefs';
import type { Gradient } from '../gradient/gradient.class';
import { createCollectionMixin } from '../mixins/collection.mixin';
import { CommonMethods } from '../mixins/shared_methods.mixin';
import type { Pattern } from '../pattern.class';
import { Point } from '../point.class';
import type { FabricObject } from '../shapes/Object/FabricObject';
import type { TCachedFabricObject } from '../shapes/Object/Object';
import type { Rect } from '../shapes/rect.class';
import {
ImageFormat,
TCornerPoint,
TDataUrlOptions,
TFiller,
TMat2D,
TSize,
TSVGReviver,
TToCanvasElementOptions,
TValidToObjectMethod,
} from '../typedefs';
import {
cancelAnimFrame,
requestAnimFrame,
} from '../util/animation/AnimationFrameProvider';
import {
cleanUpJsdomNode,
getElementOffset,
getNodeCanvas,
} from '../util/dom_misc';
import { uid } from '../util/internals/uid';
import { createCanvasElement, isHTMLCanvas, toDataURL } from '../util/misc/dom';
import { invertTransform, transformPoint } from '../util/misc/matrix';
import {
enlivenObjectEnlivables,
EnlivenObjectOptions,
enlivenObjects,
} from '../util/misc/objectEnlive';
import { pick } from '../util/misc/pick';
import { matrixToSVG } from '../util/misc/svgParsing';
import { toFixed } from '../util/misc/toFixed';
import { isCollection, isFiller, isTextObject } from '../util/types';
const CANVAS_INIT_ERROR = 'Could not initialize `canvas` element';
export type TCanvasSizeOptions = {
backstoreOnly?: boolean;
cssOnly?: boolean;
};
export type TSVGExportOptions = {
suppressPreamble?: boolean;
viewBox?: {
x: number;
y: number;
width: number;
height: number;
};
encoding?: 'UTF-8'; // test Encoding type and see what happens
width?: string;
height?: string;
reviver?: TSVGReviver;
};
type TCanvasHydrationOption = {
signal?: AbortSignal;
};
/**
* Static canvas class
* @see {@link http://fabricjs.com/static_canvas|StaticCanvas demo}
* @fires before:render
* @fires after:render
* @fires canvas:cleared
* @fires object:added
* @fires object:removed
*/
// TODO: fix `EventSpec` inheritance https://github.com/microsoft/TypeScript/issues/26154#issuecomment-1366616260
export class StaticCanvas<
EventSpec extends StaticCanvasEvents = StaticCanvasEvents
> extends createCollectionMixin(CommonMethods<CanvasEvents>) {
/**
* Background color of canvas instance.
* @type {(String|TFiller)}
* @default
*/
declare backgroundColor: TFiller | string;
/**
* 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 FabricObject
* @default
*/
declare backgroundImage: FabricObject | null;
/**
* Overlay color of canvas instance.
* @since 1.3.9
* @type {(String|TFiller)}
* @default
*/
declare overlayColor: TFiller | string;
/**
* 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 FabricObject
* @default
*/
declare overlayImage: FabricObject | null;
/**
* Indicates whether toObject/toDatalessObject should include default values
* if set to false, takes precedence over the object value.
* @type Boolean
* @default
*/
declare includeDefaultValues: boolean;
/**
* Indicates whether {@link add}, {@link insertAt} and {@link remove},
* {@link moveTo}, {@link 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 queued 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
*/
declare renderOnAddRemove: boolean;
/**
* Indicates whether object controls (borders/controls) are rendered above overlay image
* @type Boolean
* @default
*/
declare controlsAboveOverlay: boolean;
/**
* Indicates whether the browser can be scrolled when using a touchscreen and dragging on the canvas
* @type Boolean
* @default
*/
declare allowTouchScrolling: boolean;
/**
* Indicates whether this canvas will use image smoothing, this is on by default in browsers
* @type Boolean
* @default
*/
declare imageSmoothingEnabled: boolean;
/**
* 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
*/
declare viewportTransform: TMat2D;
/**
* if set to false background image is not affected by viewport transform
* @since 1.6.3
* @type Boolean
* @todo we should really find a different way to do this
* @default
*/
declare backgroundVpt: boolean;
/**
* if set to false overlya image is not affected by viewport transform
* @since 1.6.3
* @type Boolean
* @todo we should really find a different way to do this
* @default
*/
declare overlayVpt: boolean;
/**
* When true, canvas is scaled by devicePixelRatio for better rendering on retina screens
* @type Boolean
* @default
*/
declare enableRetinaScaling: boolean;
/**
* 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.
*/
declare vptCoords: TCornerPoint;
/**
* 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.
* @type Boolean
* @default
*/
declare skipOffscreen: boolean;
/**
* 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 FabricObject
*/
declare clipPath: FabricObject;
/**
* A reference to the canvas actual HTMLCanvasElement.
* Can be use to read the raw pixels, but never write or manipulate
* @type HTMLCanvasElement
*/
declare lowerCanvasEl: HTMLCanvasElement;
declare contextContainer: CanvasRenderingContext2D;
/**
* Width in virtual/logical pixels of the canvas.
* The canvas can be larger than width if retina scaling is active
* @type number
*/
declare width: number;
/**
* Height in virtual/logical pixels of the canvas.
* The canvas can be taller than width if retina scaling is active
* @type height
*/
declare height: number;
/**
* If true the Canvas is in the process or has been disposed/destroyed.
* No more rendering operation will be executed on this canvas.
* @type boolean
*/
declare destroyed?: boolean;
/**
* Started the process of disposing but not done yet.
* WIll likely complete the render cycle already scheduled but stopping adding more.
* @type boolean
*/
declare disposed?: boolean;
/**
* Keeps a copy of the canvas style before setting retina scaling and other potions
* in order to return it to original state on dispose
* @type string
*/
declare _originalCanvasStyle?: string;
declare renderAndResetBound: () => void;
declare requestRenderAllBound: () => void;
declare _offset: { left: number; top: number };
protected declare hasLostContext: boolean;
protected declare nextRenderHandle: number;
// reference to
protected declare __cleanupTask?: {
(): void;
kill: (reason?: any) => void;
};
constructor(el: string | HTMLCanvasElement, options = {}) {
super();
this._init(el, options);
}
add(...objects: FabricObject[]) {
const size = super.add(...objects);
objects.length > 0 && this.renderOnAddRemove && this.requestRenderAll();
return size;
}
insertAt(index: number, ...objects: FabricObject[]) {
const size = super.insertAt(index, ...objects);
objects.length > 0 && this.renderOnAddRemove && this.requestRenderAll();
return size;
}
remove(...objects: FabricObject[]) {
const removed = super.remove(...objects);
removed.length > 0 && this.renderOnAddRemove && this.requestRenderAll();
return removed;
}
_onObjectAdded(obj: FabricObject) {
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 });
}
_onObjectRemoved(obj: FabricObject) {
obj._set('canvas', undefined);
this.fire('object:removed', { target: obj });
obj.fire('removed', { target: this });
}
_onStackOrderChanged() {
this.renderOnAddRemove && this.requestRenderAll();
}
/**
* @private
* @param {HTMLCanvasElement | String} el <canvas> element to initialize instance on
* @param {Object} [options] Options object
*/
_init(el: string | HTMLCanvasElement, options = {}) {
this.renderAndResetBound = this.renderAndReset.bind(this);
this.requestRenderAllBound = this.requestRenderAll.bind(this);
this._initStatic(el, options);
this._isRetinaScaling() && this._initRetinaScaling();
this.calcViewportBoundaries();
}
/**
* @private
* @param {HTMLCanvasElement | String} el <canvas> element to initialize instance on
* @param {Object} [options] Options object
*/
_initStatic(el: string | HTMLCanvasElement, options = {}) {
this._objects = [];
this._createLowerCanvas(el);
this._originalCanvasStyle = this.lowerCanvasEl.style.cssText;
this._initOptions(options);
this.calcOffset();
}
/**
* @private
*/
_isRetinaScaling() {
return config.devicePixelRatio > 1 && this.enableRetinaScaling;
}
/**
* @private
* @return {Number} retinaScaling if applied, otherwise 1;
*/
getRetinaScaling() {
return this._isRetinaScaling() ? Math.max(1, config.devicePixelRatio) : 1;
}
/**
* @private
*/
_initRetinaScaling() {
this.__initRetinaScaling(this.lowerCanvasEl, this.contextContainer);
}
__initRetinaScaling(
canvas: HTMLCanvasElement,
context: CanvasRenderingContext2D
) {
const scaleRatio = config.devicePixelRatio;
canvas.setAttribute('width', (this.width * scaleRatio).toString());
canvas.setAttribute('height', (this.height * scaleRatio).toString());
context.scale(scaleRatio, scaleRatio);
}
/**
* Calculates canvas element offset relative to the document
* This method is also attached as "resize" event handler of window
*/
calcOffset() {
return (this._offset = getElementOffset(this.lowerCanvasEl));
}
/**
* @private
*/
_createCanvasElement() {
const element = createCanvasElement();
if (!element) {
throw new Error(CANVAS_INIT_ERROR);
}
if (typeof element.getContext === 'undefined') {
throw new Error(CANVAS_INIT_ERROR);
}
return element;
}
/**
* @private
* @param {Object} [options] Options object
*/
_initOptions(options = {}) {
const lowerCanvasEl = this.lowerCanvasEl;
this.set(options);
this.width = this.width || lowerCanvasEl.width || 0;
this.height = this.height || lowerCanvasEl.height || 0;
this.viewportTransform = [...this.viewportTransform];
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';
}
/**
* Creates a bottom canvas
* @private
* @param {HTMLElement} [canvasEl]
*/
_createLowerCanvas(canvasEl: HTMLCanvasElement | string) {
// canvasEl === 'HTMLCanvasElement' does not work on jsdom/node
if (isHTMLCanvas(canvasEl)) {
this.lowerCanvasEl = canvasEl;
} else {
this.lowerCanvasEl =
getEnv().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');
this.contextContainer = this.lowerCanvasEl.getContext('2d')!;
}
/**
* Returns canvas width (in px)
* @return {Number}
*/
getWidth(): number {
return this.width;
}
/**
* Returns canvas height (in px)
* @return {Number}
*/
getHeight(): number {
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
* @deprecated will be removed in 7.0
*/
setWidth(value: number, options: TCanvasSizeOptions) {
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
* @deprecated will be removed in 7.0
*/
setHeight(value: number, options: TCanvasSizeOptions) {
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
*/
setDimensions(
dimensions: Partial<TSize>,
{ cssOnly = false, backstoreOnly = false }: TCanvasSizeOptions = {}
) {
Object.entries(dimensions).forEach(([prop, value]) => {
let cssValue = `${value}`;
if (!cssOnly) {
this._setBackstoreDimension(prop as keyof TSize, value);
cssValue += 'px';
this.hasLostContext = true;
}
if (!backstoreOnly) {
this._setCssDimension(prop as keyof TSize, cssValue);
}
});
this._isRetinaScaling() && this._initRetinaScaling();
this.calcOffset();
if (!cssOnly) {
this.requestRenderAll();
}
}
/**
* Helper for setting width/height
* @private
* @param {String} prop property (width|height)
* @param {Number} value value to set property to
* @todo subclass in canvas and handle upperCanvasEl there.
*/
_setBackstoreDimension(prop: keyof TSize, value: number) {
this.lowerCanvasEl[prop] = value;
this[prop] = value;
}
/**
* Helper for setting css width/height
* @private
* @param {String} prop property (width|height)
* @param {String} value value to set property to
* @todo subclass in canvas and handle upperCanvasEl there.
*/
_setCssDimension(prop: keyof TSize, value: string) {
this.lowerCanvasEl.style[prop] = value;
}
/**
* Returns canvas zoom level
* @return {Number}
*/
getZoom() {
return this.viewportTransform[0];
}
/**
* Sets viewport transformation of this canvas instance
* @param {Array} vpt a Canvas 2D API transform matrix
*/
setViewportTransform(vpt: TMat2D) {
const activeObject = this._activeObject,
backgroundObject = this.backgroundImage,
overlayObject = this.overlayImage,
len = this._objects.length;
this.viewportTransform = vpt;
for (let i = 0; i < len; i++) {
const object = this._objects[i];
object.group || object.setCoords();
}
if (activeObject) {
activeObject.setCoords();
}
if (backgroundObject) {
backgroundObject.setCoords();
}
if (overlayObject) {
overlayObject.setCoords();
}
this.calcViewportBoundaries();
this.renderOnAddRemove && this.requestRenderAll();
}
/**
* 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
*/
zoomToPoint(point: Point, value: number) {
// TODO: just change the scale, preserve other transformations
const before = point,
vpt: TMat2D = [...this.viewportTransform];
const newPoint = transformPoint(point, invertTransform(vpt));
vpt[0] = value;
vpt[3] = value;
const after = transformPoint(newPoint, vpt);
vpt[4] += before.x - after.x;
vpt[5] += before.y - after.y;
this.setViewportTransform(vpt);
}
/**
* Sets zoom level of this canvas instance
* @param {Number} value to set zoom to, less than 1 zooms out
*/
setZoom(value: number) {
this.zoomToPoint(new Point(0, 0), value);
}
/**
* Pan viewport so as to place point at top left corner of canvas
* @param {Point} point to move to
*/
absolutePan(point: Point) {
const vpt: TMat2D = [...this.viewportTransform];
vpt[4] = -point.x;
vpt[5] = -point.y;
return this.setViewportTransform(vpt);
}
/**
* Pans viewpoint relatively
* @param {Point} point (position vector) to move by
*/
relativePan(point: 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() {
return this.lowerCanvasEl;
}
/**
* Clears specified context of canvas element
* @param {CanvasRenderingContext2D} ctx Context to clear
*/
clearContext(ctx: CanvasRenderingContext2D) {
ctx.clearRect(0, 0, this.width, this.height);
}
/**
* Returns context of canvas where objects are drawn
* @return {CanvasRenderingContext2D}
*/
getContext() {
return this.contextContainer;
}
/**
* Clears all contexts (background, main, top) of an instance
*/
clear() {
this.remove(...this.getObjects());
this.backgroundImage = null;
this.overlayImage = null;
this.backgroundColor = '';
this.overlayColor = '';
this.clearContext(this.contextContainer);
this.fire('canvas:cleared');
this.renderOnAddRemove && this.requestRenderAll();
}
/**
* Renders the canvas
*/
renderAll() {
this.cancelRequestedRender();
if (this.destroyed) {
return;
}
this.renderCanvas(this.contextContainer, this._objects);
}
/**
* 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
*/
renderAndReset() {
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.
*/
requestRenderAll() {
if (!this.nextRenderHandle && !this.disposed && !this.destroyed) {
this.nextRenderHandle = requestAnimFrame(this.renderAndResetBound);
}
}
/**
* 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(): TCornerPoint {
const 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() {
if (this.nextRenderHandle) {
cancelAnimFrame(this.nextRenderHandle);
this.nextRenderHandle = 0;
}
}
/**
* Renders background, objects, overlay and controls.
* @param {CanvasRenderingContext2D} ctx
* @param {Array} objects to render
*/
renderCanvas(ctx: CanvasRenderingContext2D, objects: FabricObject[]) {
if (this.destroyed) {
return;
}
const v = this.viewportTransform,
path = this.clipPath;
this.calcViewportBoundaries();
this.clearContext(ctx);
ctx.imageSmoothingEnabled = this.imageSmoothingEnabled;
// node-canvas
// @ts-ignore
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, path as TCachedFabricObject);
}
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(
ctx: CanvasRenderingContext2D,
clipPath: TCachedFabricObject
) {
const v = this.viewportTransform;
ctx.save();
ctx.transform(...v);
// DEBUG: uncomment this line, comment the following
// ctx.globalAlpha = 0.4;
ctx.globalCompositeOperation = 'destination-in';
clipPath.transform(ctx);
ctx.scale(1 / clipPath.zoomX, 1 / clipPath.zoomY);
ctx.drawImage(
clipPath._cacheCanvas,
-clipPath.cacheTranslationX,
-clipPath.cacheTranslationY
);
ctx.restore();
}
/**
* @private
* @param {CanvasRenderingContext2D} ctx Context to render on
* @param {Array} objects to render
*/
_renderObjects(ctx: CanvasRenderingContext2D, objects: FabricObject[]) {
for (let 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(
ctx: CanvasRenderingContext2D,
property: 'background' | 'overlay'
) {
const fill = this[`${property}Color`],
object = this[`${property}Image`],
v = this.viewportTransform,
needsVpt = this[`${property}Vpt`];
if (!fill && !object) {
return;
}
const isAFiller = isFiller(fill);
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 = isAFiller ? fill.toLive(ctx /* this */) : fill;
if (needsVpt) {
ctx.transform(...v);
}
if (isAFiller) {
ctx.transform(1, 0, 0, 1, fill.offsetX || 0, fill.offsetY || 0);
const m = ((fill as Gradient<'linear'>).gradientTransform ||
(fill as Pattern).patternTransform) as TMat2D;
m && ctx.transform(...m);
}
ctx.fill();
ctx.restore();
}
if (object) {
ctx.save();
if (needsVpt) {
ctx.transform(...v);
}
object.render(ctx);
ctx.restore();
}
}
/**
* @private
* @param {CanvasRenderingContext2D} ctx Context to render on
*/
_renderBackground(ctx: CanvasRenderingContext2D) {
this._renderBackgroundOrOverlay(ctx, 'background');
}
/**
* @private
* @param {CanvasRenderingContext2D} ctx Context to render on
*/
_renderOverlay(ctx: CanvasRenderingContext2D) {
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() {
return {
top: this.height / 2,
left: this.width / 2,
};
}
/**
* Returns coordinates of a center of canvas.
* @return {Point}
*/
getCenterPoint() {
return new Point(this.width / 2, this.height / 2);
}
/**
* Centers object horizontally in the canvas
*/
centerObjectH(object: FabricObject) {
return this._centerObject(
object,
new Point(this.getCenterPoint().x, object.getCenterPoint().y)
);
}
/**
* Centers object vertically in the canvas
* @param {FabricObject} object Object to center vertically
*/
centerObjectV(object: FabricObject) {
return this._centerObject(
object,
new Point(object.getCenterPoint().x, this.getCenterPoint().y)
);
}
/**
* Centers object vertically and horizontally in the canvas
* @param {FabricObject} object Object to center vertically and horizontally
*/
centerObject(object: FabricObject) {
return this._centerObject(object, this.getCenterPoint());
}
/**
* Centers object vertically and horizontally in the viewport
* @param {FabricObject} object Object to center vertically and horizontally
*/
viewportCenterObject(object: FabricObject) {
return this._centerObject(object, this.getVpCenter());
}
/**
* Centers object horizontally in the viewport, object.top is unchanged
* @param {FabricObject} object Object to center vertically and horizontally
*/
viewportCenterObjectH(object: FabricObject) {
return this._centerObject(
object,
new Point(this.getVpCenter().x, object.getCenterPoint().y)
);
}
/**
* Centers object Vertically in the viewport, object.top is unchanged
* @param {FabricObject} object Object to center vertically and horizontally
*/
viewportCenterObjectV(object: FabricObject) {
return this._centerObject(
object,
new Point(object.getCenterPoint().x, this.getVpCenter().y)
);
}
/**
* Calculate the point in canvas that correspond to the center of actual viewport.
* @return {Point} vpCenter, viewport center
*/
getVpCenter(): Point {
return transformPoint(
this.getCenterPoint(),
invertTransform(this.viewportTransform)
);
}
/**
* @private
* @param {FabricObject} object Object to center
* @param {Point} center Center point
*/
_centerObject(object: FabricObject, center: Point) {
object.setXY(center, 'center', 'center');
object.setCoords();