1136 lines
34 KiB
TypeScript
1136 lines
34 KiB
TypeScript
import React from "react";
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import ReactDOM from "react-dom";
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import rough from "roughjs/bin/wrappers/rough";
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import { RoughCanvas } from "roughjs/bin/canvas";
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import { FontAwesomeIcon } from "@fortawesome/react-fontawesome";
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import {
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faMousePointer,
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faSquare,
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faCircle,
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faLongArrowAltRight,
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faFont
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} from "@fortawesome/free-solid-svg-icons";
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import { moveOneLeft, moveAllLeft } from "./zindex";
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import "./styles.css";
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type ExcalidrawElement = ReturnType<typeof newElement>;
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type ExcalidrawTextElement = ExcalidrawElement & {
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type: "text";
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font: string;
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text: string;
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actualBoundingBoxAscent: number;
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};
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const LOCAL_STORAGE_KEY = "excalidraw";
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const LOCAL_STORAGE_KEY_STATE = "excalidraw-state";
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let elements = Array.of<ExcalidrawElement>();
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// https://stackoverflow.com/questions/521295/seeding-the-random-number-generator-in-javascript/47593316#47593316
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const LCG = (seed: number) => () =>
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((2 ** 31 - 1) & (seed = Math.imul(48271, seed))) / 2 ** 31;
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function randomSeed() {
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return Math.floor(Math.random() * 2 ** 31);
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}
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// Unfortunately, roughjs doesn't support a seed attribute (https://github.com/pshihn/rough/issues/27).
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// We can achieve the same result by overriding the Math.random function with a
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// pseudo random generator that supports a random seed and swapping it back after.
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function withCustomMathRandom<T>(seed: number, cb: () => T): T {
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const random = Math.random;
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Math.random = LCG(seed);
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const result = cb();
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Math.random = random;
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return result;
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}
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// https://stackoverflow.com/a/6853926/232122
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function distanceBetweenPointAndSegment(
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x: number,
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y: number,
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x1: number,
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y1: number,
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x2: number,
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y2: number
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) {
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const A = x - x1;
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const B = y - y1;
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const C = x2 - x1;
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const D = y2 - y1;
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const dot = A * C + B * D;
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const lenSquare = C * C + D * D;
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let param = -1;
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if (lenSquare !== 0) {
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// in case of 0 length line
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param = dot / lenSquare;
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}
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let xx, yy;
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if (param < 0) {
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xx = x1;
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yy = y1;
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} else if (param > 1) {
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xx = x2;
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yy = y2;
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} else {
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xx = x1 + param * C;
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yy = y1 + param * D;
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}
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const dx = x - xx;
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const dy = y - yy;
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return Math.hypot(dx, dy);
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}
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function hitTest(element: ExcalidrawElement, x: number, y: number): boolean {
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// For shapes that are composed of lines, we only enable point-selection when the distance
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// of the click is less than x pixels of any of the lines that the shape is composed of
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const lineThreshold = 10;
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if (element.type === "ellipse") {
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// https://stackoverflow.com/a/46007540/232122
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const px = Math.abs(x - element.x - element.width / 2);
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const py = Math.abs(y - element.y - element.height / 2);
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let tx = 0.707;
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let ty = 0.707;
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const a = element.width / 2;
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const b = element.height / 2;
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[0, 1, 2, 3].forEach(x => {
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const xx = a * tx;
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const yy = b * ty;
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const ex = ((a * a - b * b) * tx ** 3) / a;
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const ey = ((b * b - a * a) * ty ** 3) / b;
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const rx = xx - ex;
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const ry = yy - ey;
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const qx = px - ex;
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const qy = py - ey;
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const r = Math.hypot(ry, rx);
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const q = Math.hypot(qy, qx);
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tx = Math.min(1, Math.max(0, ((qx * r) / q + ex) / a));
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ty = Math.min(1, Math.max(0, ((qy * r) / q + ey) / b));
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const t = Math.hypot(ty, tx);
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tx /= t;
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ty /= t;
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});
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return Math.hypot(a * tx - px, b * ty - py) < lineThreshold;
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} else if (element.type === "rectangle") {
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const x1 = getElementAbsoluteX1(element);
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const x2 = getElementAbsoluteX2(element);
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const y1 = getElementAbsoluteY1(element);
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const y2 = getElementAbsoluteY2(element);
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// (x1, y1) --A-- (x2, y1)
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// |D |B
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// (x1, y2) --C-- (x2, y2)
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return (
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distanceBetweenPointAndSegment(x, y, x1, y1, x2, y1) < lineThreshold || // A
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distanceBetweenPointAndSegment(x, y, x2, y1, x2, y2) < lineThreshold || // B
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distanceBetweenPointAndSegment(x, y, x2, y2, x1, y2) < lineThreshold || // C
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distanceBetweenPointAndSegment(x, y, x1, y2, x1, y1) < lineThreshold // D
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);
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} else if (element.type === "arrow") {
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let [x1, y1, x2, y2, x3, y3, x4, y4] = getArrowPoints(element);
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// The computation is done at the origin, we need to add a translation
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x -= element.x;
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y -= element.y;
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return (
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// \
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distanceBetweenPointAndSegment(x, y, x3, y3, x2, y2) < lineThreshold ||
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// -----
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distanceBetweenPointAndSegment(x, y, x1, y1, x2, y2) < lineThreshold ||
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// /
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distanceBetweenPointAndSegment(x, y, x4, y4, x2, y2) < lineThreshold
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);
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} else if (element.type === "text") {
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const x1 = getElementAbsoluteX1(element);
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const x2 = getElementAbsoluteX2(element);
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const y1 = getElementAbsoluteY1(element);
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const y2 = getElementAbsoluteY2(element);
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return x >= x1 && x <= x2 && y >= y1 && y <= y2;
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} else if (element.type === "selection") {
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console.warn("This should not happen, we need to investigate why it does.");
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return false;
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} else {
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throw new Error("Unimplemented type " + element.type);
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}
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}
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function newElement(
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type: string,
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x: number,
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y: number,
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strokeColor: string,
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backgroundColor: string,
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width = 0,
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height = 0
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) {
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const element = {
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type: type,
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x: x,
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y: y,
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width: width,
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height: height,
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isSelected: false,
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strokeColor: strokeColor,
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backgroundColor: backgroundColor,
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seed: randomSeed(),
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draw(
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rc: RoughCanvas,
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context: CanvasRenderingContext2D,
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sceneState: SceneState
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) {}
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};
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return element;
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}
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type SceneState = {
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scrollX: number;
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scrollY: number;
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// null indicates transparent bg
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viewBackgroundColor: string | null;
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};
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const SCROLLBAR_WIDTH = 6;
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const SCROLLBAR_MARGIN = 4;
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const SCROLLBAR_COLOR = "rgba(0,0,0,0.3)";
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function getScrollbars(
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canvasWidth: number,
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canvasHeight: number,
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scrollX: number,
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scrollY: number
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) {
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// horizontal scrollbar
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const sceneWidth = canvasWidth + Math.abs(scrollX);
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const scrollBarWidth = (canvasWidth * canvasWidth) / sceneWidth;
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const scrollBarX = scrollX > 0 ? 0 : canvasWidth - scrollBarWidth;
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const horizontalScrollBar = {
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x: scrollBarX + SCROLLBAR_MARGIN,
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y: canvasHeight - SCROLLBAR_WIDTH - SCROLLBAR_MARGIN,
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width: scrollBarWidth - SCROLLBAR_MARGIN * 2,
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height: SCROLLBAR_WIDTH
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};
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// vertical scrollbar
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const sceneHeight = canvasHeight + Math.abs(scrollY);
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const scrollBarHeight = (canvasHeight * canvasHeight) / sceneHeight;
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const scrollBarY = scrollY > 0 ? 0 : canvasHeight - scrollBarHeight;
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const verticalScrollBar = {
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x: canvasWidth - SCROLLBAR_WIDTH - SCROLLBAR_MARGIN,
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y: scrollBarY + SCROLLBAR_MARGIN,
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width: SCROLLBAR_WIDTH,
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height: scrollBarHeight - SCROLLBAR_WIDTH * 2
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};
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return {
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horizontal: horizontalScrollBar,
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vertical: verticalScrollBar
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};
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}
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function renderScene(
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rc: RoughCanvas,
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context: CanvasRenderingContext2D,
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sceneState: SceneState
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) {
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if (!context) return;
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const fillStyle = context.fillStyle;
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if (typeof sceneState.viewBackgroundColor === "string") {
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context.fillStyle = sceneState.viewBackgroundColor;
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context.fillRect(-0.5, -0.5, canvas.width, canvas.height);
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} else {
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context.clearRect(-0.5, -0.5, canvas.width, canvas.height);
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}
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context.fillStyle = fillStyle;
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elements.forEach(element => {
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element.draw(rc, context, sceneState);
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if (element.isSelected) {
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const margin = 4;
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const elementX1 = getElementAbsoluteX1(element);
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const elementX2 = getElementAbsoluteX2(element);
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const elementY1 = getElementAbsoluteY1(element);
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const elementY2 = getElementAbsoluteY2(element);
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const lineDash = context.getLineDash();
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context.setLineDash([8, 4]);
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context.strokeRect(
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elementX1 - margin + sceneState.scrollX,
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elementY1 - margin + sceneState.scrollY,
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elementX2 - elementX1 + margin * 2,
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elementY2 - elementY1 + margin * 2
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);
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context.setLineDash(lineDash);
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}
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});
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const scrollBars = getScrollbars(
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context.canvas.width,
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context.canvas.height,
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sceneState.scrollX,
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sceneState.scrollY
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);
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context.fillStyle = SCROLLBAR_COLOR;
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context.fillRect(
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scrollBars.horizontal.x,
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scrollBars.horizontal.y,
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scrollBars.horizontal.width,
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scrollBars.horizontal.height
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);
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context.fillRect(
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scrollBars.vertical.x,
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scrollBars.vertical.y,
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scrollBars.vertical.width,
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scrollBars.vertical.height
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);
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context.fillStyle = fillStyle;
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}
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function exportAsPNG({
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exportBackground,
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exportVisibleOnly,
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exportPadding = 10,
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viewBackgroundColor
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}: {
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exportBackground: boolean;
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exportVisibleOnly: boolean;
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exportPadding?: number;
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viewBackgroundColor: string;
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}) {
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if (!elements.length) return window.alert("Cannot export empty canvas.");
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// deselect & rerender
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clearSelection();
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ReactDOM.render(<App />, rootElement, () => {
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// calculate visible-area coords
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let subCanvasX1 = Infinity;
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let subCanvasX2 = 0;
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let subCanvasY1 = Infinity;
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let subCanvasY2 = 0;
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elements.forEach(element => {
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subCanvasX1 = Math.min(subCanvasX1, getElementAbsoluteX1(element));
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subCanvasX2 = Math.max(subCanvasX2, getElementAbsoluteX2(element));
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subCanvasY1 = Math.min(subCanvasY1, getElementAbsoluteY1(element));
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subCanvasY2 = Math.max(subCanvasY2, getElementAbsoluteY2(element));
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});
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// create temporary canvas from which we'll export
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const tempCanvas = document.createElement("canvas");
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const tempCanvasCtx = tempCanvas.getContext("2d")!;
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tempCanvas.style.display = "none";
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document.body.appendChild(tempCanvas);
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tempCanvas.width = exportVisibleOnly
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? subCanvasX2 - subCanvasX1 + exportPadding * 2
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: canvas.width;
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tempCanvas.height = exportVisibleOnly
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? subCanvasY2 - subCanvasY1 + exportPadding * 2
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: canvas.height;
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// if we're exporting without bg, we need to rerender the scene without it
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// (it's reset again, below)
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if (!exportBackground) {
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renderScene(rc, context, {
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viewBackgroundColor: null,
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scrollX: 0,
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scrollY: 0
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});
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}
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// copy our original canvas onto the temp canvas
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tempCanvasCtx.drawImage(
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canvas, // source
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exportVisibleOnly // sx
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? subCanvasX1 - exportPadding
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: 0,
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exportVisibleOnly // sy
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? subCanvasY1 - exportPadding
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: 0,
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exportVisibleOnly // sWidth
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? subCanvasX2 - subCanvasX1 + exportPadding * 2
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: canvas.width,
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exportVisibleOnly // sHeight
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? subCanvasY2 - subCanvasY1 + exportPadding * 2
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: canvas.height,
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0, // dx
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0, // dy
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exportVisibleOnly ? tempCanvas.width : canvas.width, // dWidth
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exportVisibleOnly ? tempCanvas.height : canvas.height // dHeight
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);
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// reset transparent bg back to original
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if (!exportBackground) {
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renderScene(rc, context, { viewBackgroundColor, scrollX: 0, scrollY: 0 });
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}
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// create a temporary <a> elem which we'll use to download the image
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const link = document.createElement("a");
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link.setAttribute("download", "excalidraw.png");
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link.setAttribute("href", tempCanvas.toDataURL("image/png"));
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link.click();
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// clean up the DOM
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link.remove();
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if (tempCanvas !== canvas) tempCanvas.remove();
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});
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}
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function rotate(x1: number, y1: number, x2: number, y2: number, angle: number) {
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// 𝑎′𝑥=(𝑎𝑥−𝑐𝑥)cos𝜃−(𝑎𝑦−𝑐𝑦)sin𝜃+𝑐𝑥
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// 𝑎′𝑦=(𝑎𝑥−𝑐𝑥)sin𝜃+(𝑎𝑦−𝑐𝑦)cos𝜃+𝑐𝑦.
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// https://math.stackexchange.com/questions/2204520/how-do-i-rotate-a-line-segment-in-a-specific-point-on-the-line
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return [
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(x1 - x2) * Math.cos(angle) - (y1 - y2) * Math.sin(angle) + x2,
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(x1 - x2) * Math.sin(angle) + (y1 - y2) * Math.cos(angle) + y2
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];
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}
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// Casting second argument (DrawingSurface) to any,
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// because it is requred by TS definitions and not required at runtime
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const generator = rough.generator(null, null as any);
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function isTextElement(
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element: ExcalidrawElement
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): element is ExcalidrawTextElement {
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return element.type === "text";
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}
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function getArrowPoints(element: ExcalidrawElement) {
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const x1 = 0;
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const y1 = 0;
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const x2 = element.width;
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const y2 = element.height;
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const size = 30; // pixels
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const distance = Math.hypot(x2 - x1, y2 - y1);
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// Scale down the arrow until we hit a certain size so that it doesn't look weird
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const minSize = Math.min(size, distance / 2);
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const xs = x2 - ((x2 - x1) / distance) * minSize;
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const ys = y2 - ((y2 - y1) / distance) * minSize;
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const angle = 20; // degrees
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const [x3, y3] = rotate(xs, ys, x2, y2, (-angle * Math.PI) / 180);
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const [x4, y4] = rotate(xs, ys, x2, y2, (angle * Math.PI) / 180);
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return [x1, y1, x2, y2, x3, y3, x4, y4];
|
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}
|
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|
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function generateDraw(element: ExcalidrawElement) {
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if (element.type === "selection") {
|
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element.draw = (rc, context, { scrollX, scrollY }) => {
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const fillStyle = context.fillStyle;
|
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context.fillStyle = "rgba(0, 0, 255, 0.10)";
|
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context.fillRect(
|
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element.x + scrollX,
|
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element.y + scrollY,
|
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element.width,
|
||
element.height
|
||
);
|
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context.fillStyle = fillStyle;
|
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};
|
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} else if (element.type === "rectangle") {
|
||
const shape = withCustomMathRandom(element.seed, () => {
|
||
return generator.rectangle(0, 0, element.width, element.height, {
|
||
stroke: element.strokeColor,
|
||
fill: element.backgroundColor
|
||
});
|
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});
|
||
element.draw = (rc, context, { scrollX, scrollY }) => {
|
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context.translate(element.x + scrollX, element.y + scrollY);
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||
rc.draw(shape);
|
||
context.translate(-element.x - scrollX, -element.y - scrollY);
|
||
};
|
||
} else if (element.type === "ellipse") {
|
||
const shape = withCustomMathRandom(element.seed, () =>
|
||
generator.ellipse(
|
||
element.width / 2,
|
||
element.height / 2,
|
||
element.width,
|
||
element.height,
|
||
{ stroke: element.strokeColor, fill: element.backgroundColor }
|
||
)
|
||
);
|
||
element.draw = (rc, context, { scrollX, scrollY }) => {
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||
context.translate(element.x + scrollX, element.y + scrollY);
|
||
rc.draw(shape);
|
||
context.translate(-element.x - scrollX, -element.y - scrollY);
|
||
};
|
||
} else if (element.type === "arrow") {
|
||
const [x1, y1, x2, y2, x3, y3, x4, y4] = getArrowPoints(element);
|
||
const shapes = withCustomMathRandom(element.seed, () => [
|
||
// \
|
||
generator.line(x3, y3, x2, y2, { stroke: element.strokeColor }),
|
||
// -----
|
||
generator.line(x1, y1, x2, y2, { stroke: element.strokeColor }),
|
||
// /
|
||
generator.line(x4, y4, x2, y2, { stroke: element.strokeColor })
|
||
]);
|
||
|
||
element.draw = (rc, context, { scrollX, scrollY }) => {
|
||
context.translate(element.x + scrollX, element.y + scrollY);
|
||
shapes.forEach(shape => rc.draw(shape));
|
||
context.translate(-element.x - scrollX, -element.y - scrollY);
|
||
};
|
||
return;
|
||
} else if (isTextElement(element)) {
|
||
element.draw = (rc, context, { scrollX, scrollY }) => {
|
||
const font = context.font;
|
||
context.font = element.font;
|
||
const fillStyle = context.fillStyle;
|
||
context.fillStyle = element.strokeColor;
|
||
context.fillText(
|
||
element.text,
|
||
element.x + scrollX,
|
||
element.y + element.actualBoundingBoxAscent + scrollY
|
||
);
|
||
context.fillStyle = fillStyle;
|
||
context.font = font;
|
||
};
|
||
} else {
|
||
throw new Error("Unimplemented type " + element.type);
|
||
}
|
||
}
|
||
|
||
// If the element is created from right to left, the width is going to be negative
|
||
// This set of functions retrieves the absolute position of the 4 points.
|
||
// We can't just always normalize it since we need to remember the fact that an arrow
|
||
// is pointing left or right.
|
||
function getElementAbsoluteX1(element: ExcalidrawElement) {
|
||
return element.width >= 0 ? element.x : element.x + element.width;
|
||
}
|
||
function getElementAbsoluteX2(element: ExcalidrawElement) {
|
||
return element.width >= 0 ? element.x + element.width : element.x;
|
||
}
|
||
function getElementAbsoluteY1(element: ExcalidrawElement) {
|
||
return element.height >= 0 ? element.y : element.y + element.height;
|
||
}
|
||
function getElementAbsoluteY2(element: ExcalidrawElement) {
|
||
return element.height >= 0 ? element.y + element.height : element.y;
|
||
}
|
||
|
||
function setSelection(selection: ExcalidrawElement) {
|
||
const selectionX1 = getElementAbsoluteX1(selection);
|
||
const selectionX2 = getElementAbsoluteX2(selection);
|
||
const selectionY1 = getElementAbsoluteY1(selection);
|
||
const selectionY2 = getElementAbsoluteY2(selection);
|
||
elements.forEach(element => {
|
||
const elementX1 = getElementAbsoluteX1(element);
|
||
const elementX2 = getElementAbsoluteX2(element);
|
||
const elementY1 = getElementAbsoluteY1(element);
|
||
const elementY2 = getElementAbsoluteY2(element);
|
||
element.isSelected =
|
||
element.type !== "selection" &&
|
||
selectionX1 <= elementX1 &&
|
||
selectionY1 <= elementY1 &&
|
||
selectionX2 >= elementX2 &&
|
||
selectionY2 >= elementY2;
|
||
});
|
||
}
|
||
|
||
function clearSelection() {
|
||
elements.forEach(element => {
|
||
element.isSelected = false;
|
||
});
|
||
}
|
||
|
||
function deleteSelectedElements() {
|
||
for (let i = elements.length - 1; i >= 0; --i) {
|
||
if (elements[i].isSelected) {
|
||
elements.splice(i, 1);
|
||
}
|
||
}
|
||
}
|
||
|
||
function save(state: AppState) {
|
||
localStorage.setItem(LOCAL_STORAGE_KEY, JSON.stringify(elements));
|
||
localStorage.setItem(LOCAL_STORAGE_KEY_STATE, JSON.stringify(state));
|
||
}
|
||
|
||
function restore() {
|
||
try {
|
||
const savedElements = localStorage.getItem(LOCAL_STORAGE_KEY);
|
||
const savedState = localStorage.getItem(LOCAL_STORAGE_KEY_STATE);
|
||
|
||
if (savedElements) {
|
||
elements = JSON.parse(savedElements);
|
||
elements.forEach((element: ExcalidrawElement) => generateDraw(element));
|
||
}
|
||
|
||
return savedState ? JSON.parse(savedState) : null;
|
||
} catch (e) {
|
||
elements = [];
|
||
return null;
|
||
}
|
||
}
|
||
|
||
type AppState = {
|
||
draggingElement: ExcalidrawElement | null;
|
||
elementType: string;
|
||
exportBackground: boolean;
|
||
exportVisibleOnly: boolean;
|
||
exportPadding: number;
|
||
currentItemStrokeColor: string;
|
||
currentItemBackgroundColor: string;
|
||
viewBackgroundColor: string;
|
||
scrollX: number;
|
||
scrollY: number;
|
||
};
|
||
|
||
const KEYS = {
|
||
ARROW_LEFT: "ArrowLeft",
|
||
ARROW_RIGHT: "ArrowRight",
|
||
ARROW_DOWN: "ArrowDown",
|
||
ARROW_UP: "ArrowUp",
|
||
ESCAPE: "Escape",
|
||
DELETE: "Delete",
|
||
BACKSPACE: "Backspace"
|
||
};
|
||
|
||
const SHAPES = [
|
||
{
|
||
icon: faMousePointer,
|
||
value: "selection"
|
||
},
|
||
{
|
||
icon: faSquare,
|
||
value: "rectangle"
|
||
},
|
||
{
|
||
icon: faCircle,
|
||
value: "ellipse"
|
||
},
|
||
{
|
||
icon: faLongArrowAltRight,
|
||
value: "arrow"
|
||
},
|
||
{
|
||
icon: faFont,
|
||
value: "text"
|
||
}
|
||
];
|
||
|
||
const shapesShortcutKeys = SHAPES.map(shape => shape.value[0]);
|
||
|
||
function findElementByKey(key: string) {
|
||
const defaultElement = "selection";
|
||
return SHAPES.reduce((element, shape) => {
|
||
if (shape.value[0] !== key) return element;
|
||
|
||
return shape.value;
|
||
}, defaultElement);
|
||
}
|
||
|
||
function isArrowKey(keyCode: string) {
|
||
return (
|
||
keyCode === KEYS.ARROW_LEFT ||
|
||
keyCode === KEYS.ARROW_RIGHT ||
|
||
keyCode === KEYS.ARROW_DOWN ||
|
||
keyCode === KEYS.ARROW_UP
|
||
);
|
||
}
|
||
|
||
function getSelectedIndices() {
|
||
const selectedIndices: number[] = [];
|
||
elements.forEach((element, index) => {
|
||
if (element.isSelected) {
|
||
selectedIndices.push(index);
|
||
}
|
||
});
|
||
return selectedIndices;
|
||
}
|
||
|
||
const someElementIsSelected = () =>
|
||
elements.some(element => element.isSelected);
|
||
|
||
const ELEMENT_SHIFT_TRANSLATE_AMOUNT = 5;
|
||
const ELEMENT_TRANSLATE_AMOUNT = 1;
|
||
|
||
class App extends React.Component<{}, AppState> {
|
||
public componentDidMount() {
|
||
document.addEventListener("keydown", this.onKeyDown, false);
|
||
window.addEventListener("resize", this.onResize, false);
|
||
|
||
const savedState = restore();
|
||
if (savedState) {
|
||
this.setState(savedState);
|
||
}
|
||
}
|
||
|
||
public componentWillUnmount() {
|
||
document.removeEventListener("keydown", this.onKeyDown, false);
|
||
window.removeEventListener("resize", this.onResize, false);
|
||
}
|
||
|
||
public state: AppState = {
|
||
draggingElement: null,
|
||
elementType: "selection",
|
||
exportBackground: false,
|
||
exportVisibleOnly: true,
|
||
exportPadding: 10,
|
||
currentItemStrokeColor: "#000000",
|
||
currentItemBackgroundColor: "#ffffff",
|
||
viewBackgroundColor: "#ffffff",
|
||
scrollX: 0,
|
||
scrollY: 0
|
||
};
|
||
|
||
private onResize = () => {
|
||
this.forceUpdate();
|
||
};
|
||
|
||
private onKeyDown = (event: KeyboardEvent) => {
|
||
if ((event.target as HTMLElement).nodeName === "INPUT") {
|
||
return;
|
||
}
|
||
|
||
if (event.key === KEYS.ESCAPE) {
|
||
clearSelection();
|
||
this.forceUpdate();
|
||
event.preventDefault();
|
||
} else if (event.key === KEYS.BACKSPACE || event.key === KEYS.DELETE) {
|
||
deleteSelectedElements();
|
||
this.forceUpdate();
|
||
event.preventDefault();
|
||
} else if (isArrowKey(event.key)) {
|
||
const step = event.shiftKey
|
||
? ELEMENT_SHIFT_TRANSLATE_AMOUNT
|
||
: ELEMENT_TRANSLATE_AMOUNT;
|
||
elements.forEach(element => {
|
||
if (element.isSelected) {
|
||
if (event.key === KEYS.ARROW_LEFT) element.x -= step;
|
||
else if (event.key === KEYS.ARROW_RIGHT) element.x += step;
|
||
else if (event.key === KEYS.ARROW_UP) element.y -= step;
|
||
else if (event.key === KEYS.ARROW_DOWN) element.y += step;
|
||
}
|
||
});
|
||
this.forceUpdate();
|
||
event.preventDefault();
|
||
|
||
// Send backwards: Cmd-Shift-Alt-B
|
||
} else if (
|
||
event.metaKey &&
|
||
event.shiftKey &&
|
||
event.altKey &&
|
||
event.code === "KeyB"
|
||
) {
|
||
this.moveOneLeft();
|
||
event.preventDefault();
|
||
|
||
// Send to back: Cmd-Shift-B
|
||
} else if (event.metaKey && event.shiftKey && event.code === "KeyB") {
|
||
this.moveAllLeft();
|
||
event.preventDefault();
|
||
|
||
// Select all: Cmd-A
|
||
} else if (event.metaKey && event.code === "KeyA") {
|
||
elements.forEach(element => {
|
||
element.isSelected = true;
|
||
});
|
||
this.forceUpdate();
|
||
event.preventDefault();
|
||
} else if (shapesShortcutKeys.includes(event.key.toLowerCase())) {
|
||
this.setState({ elementType: findElementByKey(event.key) });
|
||
}
|
||
};
|
||
|
||
private deleteSelectedElements = () => {
|
||
deleteSelectedElements();
|
||
this.forceUpdate();
|
||
};
|
||
|
||
private moveAllLeft = () => {
|
||
moveAllLeft(elements, getSelectedIndices());
|
||
this.forceUpdate();
|
||
};
|
||
|
||
private moveOneLeft = () => {
|
||
moveOneLeft(elements, getSelectedIndices());
|
||
this.forceUpdate();
|
||
};
|
||
|
||
public render() {
|
||
return (
|
||
<div
|
||
className="container"
|
||
onCut={e => {
|
||
e.clipboardData.setData(
|
||
"text/plain",
|
||
JSON.stringify(elements.filter(element => element.isSelected))
|
||
);
|
||
deleteSelectedElements();
|
||
this.forceUpdate();
|
||
e.preventDefault();
|
||
}}
|
||
onCopy={e => {
|
||
e.clipboardData.setData(
|
||
"text/plain",
|
||
JSON.stringify(elements.filter(element => element.isSelected))
|
||
);
|
||
e.preventDefault();
|
||
}}
|
||
onPaste={e => {
|
||
const paste = e.clipboardData.getData("text");
|
||
let parsedElements;
|
||
try {
|
||
parsedElements = JSON.parse(paste);
|
||
} catch (e) {}
|
||
if (
|
||
Array.isArray(parsedElements) &&
|
||
parsedElements.length > 0 &&
|
||
parsedElements[0].type // need to implement a better check here...
|
||
) {
|
||
clearSelection();
|
||
parsedElements.forEach(parsedElement => {
|
||
parsedElement.x += 10;
|
||
parsedElement.y += 10;
|
||
parsedElement.seed = randomSeed();
|
||
generateDraw(parsedElement);
|
||
elements.push(parsedElement);
|
||
});
|
||
this.forceUpdate();
|
||
}
|
||
e.preventDefault();
|
||
}}
|
||
>
|
||
<div className="sidePanel">
|
||
<h4>Shapes</h4>
|
||
<div className="panelTools">
|
||
{SHAPES.map(({ value, icon }) => (
|
||
<label key={value} className="tool">
|
||
<input
|
||
type="radio"
|
||
checked={this.state.elementType === value}
|
||
onChange={() => {
|
||
this.setState({ elementType: value });
|
||
clearSelection();
|
||
this.forceUpdate();
|
||
}}
|
||
/>
|
||
<div className="toolIcon">
|
||
<FontAwesomeIcon icon={icon} />
|
||
</div>
|
||
</label>
|
||
))}
|
||
</div>
|
||
<h4>Colors</h4>
|
||
<div className="panelColumn">
|
||
<label>
|
||
<input
|
||
type="color"
|
||
value={this.state.viewBackgroundColor}
|
||
onChange={e => {
|
||
this.setState({ viewBackgroundColor: e.target.value });
|
||
}}
|
||
/>
|
||
Background
|
||
</label>
|
||
<label>
|
||
<input
|
||
type="color"
|
||
value={this.state.currentItemStrokeColor}
|
||
onChange={e => {
|
||
this.setState({ currentItemStrokeColor: e.target.value });
|
||
}}
|
||
/>
|
||
Shape Stroke
|
||
</label>
|
||
<label>
|
||
<input
|
||
type="color"
|
||
value={this.state.currentItemBackgroundColor}
|
||
onChange={e => {
|
||
this.setState({ currentItemBackgroundColor: e.target.value });
|
||
}}
|
||
/>
|
||
Shape Background
|
||
</label>
|
||
</div>
|
||
<h4>Export</h4>
|
||
<div className="panelColumn">
|
||
<button
|
||
onClick={() => {
|
||
exportAsPNG({
|
||
exportBackground: this.state.exportBackground,
|
||
exportVisibleOnly: this.state.exportVisibleOnly,
|
||
exportPadding: this.state.exportPadding,
|
||
viewBackgroundColor: this.state.viewBackgroundColor
|
||
});
|
||
}}
|
||
>
|
||
Export to png
|
||
</button>
|
||
<label>
|
||
<input
|
||
type="checkbox"
|
||
checked={this.state.exportBackground}
|
||
onChange={e => {
|
||
this.setState({ exportBackground: e.target.checked });
|
||
}}
|
||
/>
|
||
background
|
||
</label>
|
||
<label>
|
||
<input
|
||
type="checkbox"
|
||
checked={this.state.exportVisibleOnly}
|
||
onChange={e => {
|
||
this.setState({ exportVisibleOnly: e.target.checked });
|
||
}}
|
||
/>
|
||
visible area only
|
||
</label>
|
||
<div>
|
||
(padding:
|
||
<input
|
||
type="number"
|
||
value={this.state.exportPadding}
|
||
onChange={e => {
|
||
this.setState({ exportPadding: Number(e.target.value) });
|
||
}}
|
||
disabled={!this.state.exportVisibleOnly}
|
||
/>
|
||
px)
|
||
</div>
|
||
</div>
|
||
{someElementIsSelected() && (
|
||
<>
|
||
<h4>Shape options</h4>
|
||
<div className="panelColumn">
|
||
<button onClick={this.deleteSelectedElements}>Delete</button>
|
||
<button>Move to front</button>
|
||
<button onClick={this.moveOneLeft}>Send backwards</button>
|
||
<button onClick={this.moveAllLeft}>Send to back</button>
|
||
</div>
|
||
</>
|
||
)}
|
||
</div>
|
||
<canvas
|
||
id="canvas"
|
||
width={window.innerWidth - 250}
|
||
height={window.innerHeight}
|
||
onWheel={e => {
|
||
e.preventDefault();
|
||
const { deltaX, deltaY } = e;
|
||
this.setState(state => ({
|
||
scrollX: state.scrollX - deltaX,
|
||
scrollY: state.scrollY - deltaY
|
||
}));
|
||
}}
|
||
onMouseDown={e => {
|
||
const x =
|
||
e.clientX -
|
||
(e.target as HTMLElement).offsetLeft -
|
||
this.state.scrollX;
|
||
const y =
|
||
e.clientY -
|
||
(e.target as HTMLElement).offsetTop -
|
||
this.state.scrollY;
|
||
const element = newElement(
|
||
this.state.elementType,
|
||
x,
|
||
y,
|
||
this.state.currentItemStrokeColor,
|
||
this.state.currentItemBackgroundColor
|
||
);
|
||
let isDraggingElements = false;
|
||
const cursorStyle = document.documentElement.style.cursor;
|
||
if (this.state.elementType === "selection") {
|
||
const hitElement = elements.find(element => {
|
||
return hitTest(element, x, y);
|
||
});
|
||
|
||
// If we click on something
|
||
if (hitElement) {
|
||
if (hitElement.isSelected) {
|
||
// If that element is not already selected, do nothing,
|
||
// we're likely going to drag it
|
||
} else {
|
||
// We unselect every other elements unless shift is pressed
|
||
if (!e.shiftKey) {
|
||
clearSelection();
|
||
}
|
||
// No matter what, we select it
|
||
hitElement.isSelected = true;
|
||
}
|
||
} else {
|
||
// If we don't click on anything, let's remove all the selected elements
|
||
clearSelection();
|
||
}
|
||
|
||
isDraggingElements = someElementIsSelected();
|
||
|
||
if (isDraggingElements) {
|
||
document.documentElement.style.cursor = "move";
|
||
}
|
||
}
|
||
|
||
if (isTextElement(element)) {
|
||
const text = prompt("What text do you want?");
|
||
if (text === null) {
|
||
return;
|
||
}
|
||
element.text = text;
|
||
element.font = "20px Virgil";
|
||
const font = context.font;
|
||
context.font = element.font;
|
||
const {
|
||
actualBoundingBoxAscent,
|
||
actualBoundingBoxDescent,
|
||
width
|
||
} = context.measureText(element.text);
|
||
element.actualBoundingBoxAscent = actualBoundingBoxAscent;
|
||
context.font = font;
|
||
const height = actualBoundingBoxAscent + actualBoundingBoxDescent;
|
||
// Center the text
|
||
element.x -= width / 2;
|
||
element.y -= actualBoundingBoxAscent;
|
||
element.width = width;
|
||
element.height = height;
|
||
}
|
||
|
||
generateDraw(element);
|
||
elements.push(element);
|
||
if (this.state.elementType === "text") {
|
||
this.setState({
|
||
draggingElement: null,
|
||
elementType: "selection"
|
||
});
|
||
element.isSelected = true;
|
||
} else {
|
||
this.setState({ draggingElement: element });
|
||
}
|
||
|
||
let lastX = x;
|
||
let lastY = y;
|
||
|
||
const onMouseMove = (e: MouseEvent) => {
|
||
const target = e.target;
|
||
if (!(target instanceof HTMLElement)) {
|
||
return;
|
||
}
|
||
|
||
if (isDraggingElements) {
|
||
const selectedElements = elements.filter(el => el.isSelected);
|
||
if (selectedElements.length) {
|
||
const x = e.clientX - target.offsetLeft - this.state.scrollX;
|
||
const y = e.clientY - target.offsetTop - this.state.scrollY;
|
||
selectedElements.forEach(element => {
|
||
element.x += x - lastX;
|
||
element.y += y - lastY;
|
||
});
|
||
lastX = x;
|
||
lastY = y;
|
||
this.forceUpdate();
|
||
return;
|
||
}
|
||
}
|
||
|
||
// It is very important to read this.state within each move event,
|
||
// otherwise we would read a stale one!
|
||
const draggingElement = this.state.draggingElement;
|
||
if (!draggingElement) return;
|
||
let width =
|
||
e.clientX -
|
||
target.offsetLeft -
|
||
draggingElement.x -
|
||
this.state.scrollX;
|
||
let height =
|
||
e.clientY -
|
||
target.offsetTop -
|
||
draggingElement.y -
|
||
this.state.scrollY;
|
||
draggingElement.width = width;
|
||
// Make a perfect square or circle when shift is enabled
|
||
draggingElement.height = e.shiftKey ? width : height;
|
||
|
||
generateDraw(draggingElement);
|
||
|
||
if (this.state.elementType === "selection") {
|
||
setSelection(draggingElement);
|
||
}
|
||
this.forceUpdate();
|
||
};
|
||
|
||
const onMouseUp = (e: MouseEvent) => {
|
||
const { draggingElement, elementType } = this.state;
|
||
|
||
window.removeEventListener("mousemove", onMouseMove);
|
||
window.removeEventListener("mouseup", onMouseUp);
|
||
|
||
document.documentElement.style.cursor = cursorStyle;
|
||
|
||
// if no element is clicked, clear the selection and redraw
|
||
if (draggingElement === null) {
|
||
clearSelection();
|
||
this.forceUpdate();
|
||
return;
|
||
}
|
||
|
||
if (elementType === "selection") {
|
||
if (isDraggingElements) {
|
||
isDraggingElements = false;
|
||
}
|
||
elements.pop();
|
||
} else {
|
||
draggingElement.isSelected = true;
|
||
}
|
||
|
||
this.setState({
|
||
draggingElement: null,
|
||
elementType: "selection"
|
||
});
|
||
this.forceUpdate();
|
||
};
|
||
|
||
window.addEventListener("mousemove", onMouseMove);
|
||
window.addEventListener("mouseup", onMouseUp);
|
||
|
||
this.forceUpdate();
|
||
}}
|
||
/>
|
||
</div>
|
||
);
|
||
}
|
||
|
||
componentDidUpdate() {
|
||
renderScene(rc, context, {
|
||
scrollX: this.state.scrollX,
|
||
scrollY: this.state.scrollY,
|
||
viewBackgroundColor: this.state.viewBackgroundColor
|
||
});
|
||
save(this.state);
|
||
}
|
||
}
|
||
|
||
const rootElement = document.getElementById("root");
|
||
ReactDOM.render(<App />, rootElement);
|
||
const canvas = document.getElementById("canvas") as HTMLCanvasElement;
|
||
const rc = rough.canvas(canvas);
|
||
const context = canvas.getContext("2d")!;
|
||
|
||
// Big hack to ensure that all the 1px lines are drawn at 1px instead of 2px
|
||
// https://stackoverflow.com/questions/13879322/drawing-a-1px-thick-line-in-canvas-creates-a-2px-thick-line/13879402#comment90766599_13879402
|
||
context.translate(0.5, 0.5);
|
||
|
||
ReactDOM.render(<App />, rootElement);
|