signal-desktop/ts/mediaEditor/util/customFabricObjectControls.ts
2021-12-03 14:28:56 -06:00

134 lines
3.4 KiB
TypeScript

// Copyright 2021 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
import { fabric } from 'fabric';
const resizeControl = new fabric.Control({
actionHandler: fabric.controlsUtils.scalingEqually,
cursorStyleHandler: () => 'se-resize',
render: (ctx: CanvasRenderingContext2D, left: number, top: number) => {
// circle
const size = 12;
ctx.save();
ctx.fillStyle = '#fff';
ctx.strokeStyle = '#fff';
ctx.lineWidth = 1;
ctx.beginPath();
ctx.arc(left, top, size, 0, 2 * Math.PI, false);
ctx.fill();
// arrows NW & SE
const arrowSize = 5;
ctx.fillStyle = '#3b3b3b';
ctx.strokeStyle = '#3b3b3b';
ctx.beginPath();
// SE
ctx.moveTo(left + 0.5, top + 0.5);
ctx.lineTo(left + arrowSize, top + arrowSize);
ctx.moveTo(left + arrowSize, top + 1);
ctx.lineTo(left + arrowSize, top + arrowSize);
ctx.lineTo(left + 1, top + arrowSize);
// NW
ctx.moveTo(left - 0.5, top - 0.5);
ctx.lineTo(left - arrowSize, top - arrowSize);
ctx.moveTo(left - arrowSize, top - 1);
ctx.lineTo(left - arrowSize, top - arrowSize);
ctx.lineTo(left - 1, top - arrowSize);
ctx.stroke();
ctx.restore();
},
x: 0.5,
y: 0.5,
});
const rotateControl = new fabric.Control({
actionHandler: fabric.controlsUtils.rotationWithSnapping,
actionName: 'rotate',
cursorStyleHandler: fabric.controlsUtils.rotationStyleHandler,
offsetY: -40,
render(
ctx: CanvasRenderingContext2D,
left: number,
top: number,
_,
target: fabric.Object
) {
const size = 5;
ctx.save();
ctx.fillStyle = '#fff';
ctx.strokeStyle = '#fff';
// connecting line
ctx.beginPath();
ctx.moveTo(left, top);
const radians = 0 - ((target.angle || 0) * Math.PI) / 180;
const targetLeft = 40 * Math.sin(radians);
const targetTop = 40 * Math.cos(radians);
ctx.lineTo(left + targetLeft, top + targetTop);
ctx.stroke();
// circle
ctx.beginPath();
ctx.moveTo(left, top);
ctx.arc(left, top, size, 0, 2 * Math.PI, false);
ctx.fill();
ctx.restore();
},
withConnection: false,
x: 0,
y: -0.5,
});
const deleteControl = new fabric.Control({
cursorStyleHandler: () => 'pointer',
// This is lifted from <http://fabricjs.com/custom-control-render>.
mouseUpHandler: (_eventData, { target }) => {
if (!target.canvas) {
return false;
}
target.canvas.remove(target);
return true;
},
render: (ctx: CanvasRenderingContext2D, left: number, top: number) => {
// circle
const size = 12;
ctx.save();
ctx.fillStyle = '#000';
ctx.strokeStyle = '#000';
ctx.lineWidth = 1;
ctx.beginPath();
ctx.arc(left, top, size, 0, 2 * Math.PI, false);
ctx.fill();
// x
const xSize = 4;
ctx.fillStyle = '#fff';
ctx.strokeStyle = '#fff';
ctx.beginPath();
const topLeft = new fabric.Point(left - xSize, top - xSize);
const topRight = new fabric.Point(left + xSize, top - xSize);
const bottomRight = new fabric.Point(left + xSize, top + xSize);
const bottomLeft = new fabric.Point(left - xSize, top + xSize);
ctx.moveTo(topLeft.x, topLeft.y);
ctx.lineTo(bottomRight.x, bottomRight.y);
ctx.moveTo(topRight.x, topRight.y);
ctx.lineTo(bottomLeft.x, bottomLeft.y);
ctx.stroke();
ctx.restore();
},
x: -0.5,
y: -0.5,
});
export const customFabricObjectControls = {
br: resizeControl,
mtr: rotateControl,
tl: deleteControl,
};