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const socket = new WebSocket("ws://localhost:5001", "tuesday");
//var exampleSocket = new WebSocket("ws://192.168.3.42:5001", "tuesday");
socket.onopen = function (event) {
console.log("Connection established");
// Display user friendly messages for the successful establishment of connection
socket.send("42");
};
socket.onmessage = function (event) {
console.log(event.data);
AddBrushPoint(JSON.parse(event.data));
DrawBrush();
SaveCanvasImage();
RedrawCanvasImage();
};
window.onbeforeunload = function () {
socket.onclose = function () { }; // disable onclose handler first
console.log("Connection terminated");
socket.close();
};
let canvas;
let context;
let savedImageData;
let dragging = false;
let strokeColor = 'black';
let fillColor = 'black';
let color = 'black';
let lineWidth = 2;
let currentTool = "brush";
let canvasHeight = 1000;
let canvasWidth = 1000;
let usingBrush = false;
let brushPoints = new Array();
class ShapeBoundingBox {
constructor(left, top, width, height) {
this.left = left;
this.top = top;
this.width = width;
this.height = height;
}
}
class DrawPoint {
constructor(x, y, mouseDown) {
this.x = x;
this.y = y;
this.mouseDown = mouseDown;
}
}
class MouseDownPos {
constructor(x, y) {
this.x = x;
this.y = y;
}
}
class Location {
constructor(x, y) {
this.x = x;
this.y = y;
}
}
let shapeBoundingBox = new ShapeBoundingBox(0, 0, 0, 0);
let mousedown = new MouseDownPos(0, 0);
let loc = new Location(0, 0);
document.addEventListener('DOMContentLoaded', setupCanvas);
function setupCanvas() {
canvas = document.getElementById('my-canvas');
context = canvas.getContext('2d');
context.strokeStyles = strokeColor;
context.lineWidth = lineWidth;
canvas.addEventListener("mousedown", ReactToMouseDown);
canvas.addEventListener("mousemove", ReactToMouseMove);
canvas.addEventListener("mouseup", ReactToMouseUp);
}
function GetMousePosition(x, y) {
let canvasSizeData = canvas.getBoundingClientRect();
return {
x: (x - canvasSizeData.left) * (canvas.width / canvasSizeData.width),
y: (y - canvasSizeData.top) * (canvas.height / canvasSizeData.height)
};
}
function SaveCanvasImage() {
savedImageData = context.getImageData(0, 0, canvas.width, canvas.height);
}
function RedrawCanvasImage() {
context.putImageData(savedImageData, 0, 0);
}
function UpdateRubberbandSizeData(location) {
shapeBoundingBox.width = Math.abs(location.x - mousedown.x);
shapeBoundingBox.height = Math.abs(location.y - mousedown.y);
if (location.x > mousedown.x) {
shapeBoundingBox.left = mousedown.x;
} else {
shapeBoundingBox.left = location.x;
}
if (location.y > mousedown.y) {
shapeBoundingBox.top = mousedown.y;
} else {
shapeBoundingBox.top = location.y;
}
}
function AddNetBrushPoint(x, y, mouseDown) {
let point = new DrawPoint(x, y, mouseDown);
socket.send(JSON.stringify(point));
AddBrushPoint(point);
}
function AddBrushPoint(point) {
brushPoints.push(point);
}
function DrawBrush() {
for (let i = 1; i < brushPoints.length; i++) {
context.beginPath();
if (brushPoints[i].mouseDown) {
context.moveTo(brushPoints[i - 1].x, brushPoints[i - 1].y);
} else {
context.moveTo(brushPoints[i].x - 1, brushPoints[i].y);
}
context.lineTo(brushPoints[i].x, brushPoints[i].y)
context.closePath();
context.stroke();
}
}
function UpdateRubberbandOnMove(location) {
UpdateRubberbandSizeData(location);
drawRubberbandShape(location);
}
function drawRubberbandShape(location) {
context.strokeStyle = strokeColor;
context.fillStyle = fillColor;
if (currentTool === "brush") {
DrawBrush();
} else if (currentTool === "line") {
context.beginPath();
context.moveTo(mousedown.x, mousedown.y);
context.lineTo(location.x, location.y);
context.closePath();
context.stroke();
} else if (currentTool === "rectangle") {
context.strokeRect(shapeBoundingBox.left, shapeBoundingBox.top,
shapeBoundingBox.width, shapeBoundingBox.height);
}
}
function ReactToMouseDown(e) {
// Change the mouse pointer to a crosshair
canvas.style.cursor = "crosshair";
// Store location
loc = GetMousePosition(e.clientX, e.clientY);
// Save the current canvas image
SaveCanvasImage();
// Store mouse position when clicked
mousedown.x = loc.x;
mousedown.y = loc.y;
// Store that yes the mouse is being held down
dragging = true;
if (currentTool === "brush") {
usingBrush = true;
AddNetBrushPoint(mousedown.x, mousedown.y);
}
};
function ReactToMouseMove(e) {
canvas.style.cursor = "crosshair";
loc = GetMousePosition(e.clientX, e.clientY);
if (currentTool === "brush" && dragging && usingBrush) {
if (loc.x > 0 && loc.x < canvasWidth && loc.y > 0 && loc.y < canvasHeight) {
AddNetBrushPoint(loc.x, loc.y, true);
}
RedrawCanvasImage();
DrawBrush();
} else if (dragging) {
RedrawCanvasImage();
UpdateRubberbandOnMove(loc);
}
};
function ReactToMouseUp(e) {
canvas.style.cursor = "default";
loc = GetMousePosition(e.clientX, e.clientY);
RedrawCanvasImage();
UpdateRubberbandOnMove(loc);
dragging = false;
usingBrush = false;
brushXPoints = new Array();
brushYPoints = new Array();
brushDownPos = new Array();
if (currentTool === "brush") {
AddBrushPoint(loc.x, loc.y);
}
}
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